Lipschitz modulus of linear and convex inequality systems with the Hausdorff metric

This paper analyzes the Lipschitz behavior of the feasible set mapping associated with linear and convex inequality systems in Rn. To start with, we deal with the parameter space of linear (finite/semi-infinite) systems identified with the corresponding sets of coefficient vectors, which are assumed to be closed subsets of Rn+1. In this framework the size of perturbations is measured by means of the (extended) Hausdorff distance. A direct antecedent, extensively studied in the literature, comes from considering the parameter space of all linear systems with a fixed index set, T, where the Chebyshev (extended) distance is used to measure perturbations. In the present work we propose an appropriate indexation strategy which allows us to establish the equality of the Lipschitz moduli of the feasible set mappings in both parametric contexts, as well as to benefit from existing results in the Chebyshev setting for transferring them to the Hausdorff one. In a second stage, the possibility of perturbing directly the set of coefficient vectors of a linear system leads to new contributions on the Lipschitz behavior of convex systems via linearization techniques. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature and Mathematical Optimization Society. Correction: The article “Lipschitz modulus of linear and convex inequality systems with the Hausdorff metric”, written by Beer,G., Cánovas, M.J., López, M.A., Parra, J.was originally published Online First without Open Access. After publication in volume 189, issue 1–2, page 75–98 the author decided to opt for Open Choice and to make the article an Open Access publication. Therefore, the copyright of the article has been changed to © The Author(s) 2020 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License. https://doi.org/10.1007/s10107-021-01751-

Sexual dichromatism of the Blue-throated Starfrontlet, <i>Coeligena helianthea</i>, hummingbird plumage

Among the many richly coloured birds, hummingbirds with their brilliant colouration are outstanding. We studied the plumage of male and female Blue-throated Starfrontlet, Coeligena helianthea, which exhibits a marked sexual dichromatism. The wide diversity of coloured feathers (blue, purple, golden, green, red) makes it an attractive species to investigate the structural basis of the colouration and to study the connection between the displayed colours and the perception by conspecifics. We analysed the optical properties of the feather barbules, applying spectrophotometry, scatterometry, and electron microscopy. Using the anatomical results, the spectral data can be interpreted by optical modelling. The reflectance spectra of the feathers of male C. helianthea strikingly overlap with the spectral sensitivities of bird photoreceptors, which suggests that the feather and photoreceptor spectra are tuned

Prediction of Methanol Production in a Carbon Dioxide Hydrogenation Plant Using Neural Networks

[EN] The objective of this research was to design a neural network (ANN) to predict the methanol flux at the outlet of a carbon dioxide dehydrogenation plant. For the development of the ANN, a database was generated, in the open-source simulation software "DWSIM", from the validation of a process described in the literature. The sample consists of 133 data pairs with four inputs: reactor pressure and temperature, mass flow of carbon dioxide and hydrogen, and one output: flow of methanol. The ANN was designed using 12 neurons in the hidden layer and it was trained with the Levenberg-Marquardt algorithm. In the training, validation and testing phase, a global mean square (RMSE) value of 0.0085 and a global regression coefficient R of 0.9442 were obtained. The network was validated through an analysis of variance (ANOVA), where the p-value for all cases was greater than 0.05, which indicates that there are no significant differences between the observations and those predicted by the ANN. Therefore, the designed ANN can be used to predict the methanol flow at the exit of a dehydrogenation plant and later for the optimization of the system.Chuquin-Vasco, D.; Parra, F.; Chuquin-Vasco, N.; Chuquin-Vasco, J.; Lo-Iacono-Ferreira, VG. (2021). Prediction of Methanol Production in a Carbon Dioxide Hydrogenation Plant Using Neural Networks. Energies. 14(13):1-18. https://doi.org/10.3390/en14133965S118141

G and P genotypes of rotavirus circulating among children with diarrhea in the Colombian northern coast

A study on the prevalence of rotavirus G and P genotypes was carried out based on 253 stool specimens obtained from children living in the Colombia northern coast region who were less than 3-years-old and who suffered from acute diarrhea. A previous study had detected the presence of rotavirus A in 90 (36.5%) of the 246 samples tested by enzyme immunoassay (EIA), and these strains were investigated in the present study. Of these, 50 strains yielded an RNA electropherotype, most of which (80.0%) had long profiles and 20.0% of which had short profiles. Genotyping of 84 positive samples indicated that 67.9% of the strains could be typed. G1 (57.9%), was the most predominant VP7 genotype, followed by G3 (21.1%), G9 (15.8%) and G2 (5.3%). Among the VP4 genotypes, P[4] (49.1%) was the most prevalent, followed by P[6] 36.4% and P[8] (14.5%). Neither G4 nor G8 nor P[9] types were detected. The most common G-P combinations were G3 P[4] (8.8%) and G9 P[6] (7.0%), followed by G1 P[4] and G1 P[8] (5.3% each). All G1 P[8] strains showed long RNA profiles, whereas G3 P[4] and G9 P[6] displayed both long and short patterns. Mixed infections involved 21.0% of strains. There was a marked diversity among strains collected, and novel strains, including G9, as well as other atypical combinations of G and P genotypes, such as G9 P[6] and G3 P[4], were found. [Int Microbiol 2004; 7(2):113-120

Iridescent colouration of male Anna's hummingbird (<i>Calypte anna</i>) caused by multilayered barbules

The male Anna's hummingbird features a brightly reddish-pink reflecting gorget, due to large stacks of melanosomes in the feather barbules, arranged in layers separated by keratin. Direct observations together with detailed scatterometry demonstrated that the barbules reflect incident light in an approximately specular manner. The structural colouration is iridescent, i.e. varies with a changing angle of light incidence. Spectrophotometrical measurements of the barbule reflectance and absorbance can be well interpreted with calculated spectra obtained with a transfer matrix method for optical multilayers, using anatomical data and measured refractive index spectra. The organization of the reflectors as a Venetian blind presumably functions to create a high spectral contrast of the male's plumage during courtship

Mejoramiento genético asistido para características reproductivas de animales domésticos : Marker assisted selection for reproductive traits in domestic animal

En los sistemas de producción animal, las características de reproducción influyen significativamente en su eficiencia y rentabilidad. La reproducción como herramienta de cambio genético necesariamente requiere de estrategias que identifiquen la variabilidad genética de los caracteres de interés; sin embargo, debido a su naturaleza compleja todos los caracteres reproductivos requieren del entendimiento de su arquitectura genética, condición que por su baja heredabilidad resulta complejo por métodos convencionales. La biotecnología genómica en la actualidad propone el mejoramiento genético sustantivo por medio del uso e implementación de marcadores genéticos, sobre todo del tipo SNP. En los últimos años se ha investigado intensivamente, en ganado ovino y bovino, la variabilidad genética de caracteres reproductivos utilizando la búsqueda de variantes alélicas en genes candidatos que expliquen esta variabilidad y puedan ser empleados durante la selección. Actualmente en algunos casos su uso es una realidad (p.e. fecundidad, tamaño de camada en razas ovinas). Para otras características aún es requerida mayor investigación y validación de sus efectos putativos. En perspectiva, el futuro avizora mejores y más intensos logros con la disminución de los costos de tipificación y el mayor entendimiento en la interacción de los genes en caracteres complejos

Tecnologías de la Información y la Comunicación aplicadas a procesos de investigación en Ciencias a nivel escolar

Una de las concepciones pedagógicas actuales para afianzar procesos de investigación en ciencias naturales a nivel escolar es la aplicación de tecnologías de la información y la comunicación (Internet, videoconferencias, mallas computacionales-grid, intranet, objetos virtuales de aprendizaje, foros aferentes online, laboratorios virtuales, redes computacionales, animaciones, recursos multimediales etc.), que permiten acercarse al mundo tecnológico actual y al tratamiento de información científica de frontera

Análise do genoma completo para identificar variações associadas à circunferência escrotal em bovinos Charolês

The scrotal circumference is one of the main characteristics related to fertility of the bovine male and female. Its study through genetic and genomic tools would help to the discovery of favorable variation and genetic architecture to promote its selection. The aim of this work was to carry out a genome- wide association study using a large microarray of SNPs, to identify variations and candidate genes associated with the studied trait, for which information from 141 Charolais bulls was used. Four markers found, rs110416965, rs110130953, rs43423602 and rs29003417, showed significant association at the genome level. Three of them are found within candidate genes (RBFOX2, TTF2 and CXCL2). This information contributes to the understanding of the genetic architecture of this trait. &nbsp;La circunferencia escrotal es una de las características realcionadas a la fertilidad del macho y la hembra bovina. Su estudio a través de herramientas genéticas y genómicas ayudaría al descubrimiento de variación favorable en su arquitectura genética para fomentar su selección. El propósito del presente trabajo fue realizar un estudio de genoma completo mediante un microarreglo de SNPs, para identificar variaciones y genes candidatos asociados a la característica, para lo que se utilizó la información de 141 toros de la raza Charolais. Cuatro marcadores encontrados, rs110416965, rs110130953, rs43423602 y rs29003417, mostraron asociación significativa a nivel de genoma. Tres de ellos se encuentran dentro de genes candidatos (RBFOX2, TTF2 y CXCL2) para ser estudiados más especificamente. Esta información contribuye al entendiemiento de la arquitectura genética de esta característicaA circunferência escrotal é uma das características relacionadas à fertilidade do macho e da fêmea bovina. Seu estudo por meio de ferramentas genéticas e genômicas auxiliaria na descoberta de variação favorável em sua arquitetura genética para promover sua seleção. O objetivo deste trabalho foi realizar um estudo do genoma completo usando um microarray de SNPs, para identificar variações e genes candidatos associados à característica, para o qual foram utilizadas informações de 141 touros Charolês. Quatro marcadores encontrados, rs110416965, rs110130953, rs43423602 e rs29003417, mostraram associação significativa no nível do genoma. Três deles foram encontrados em genes candidatos (RBFOX2, TTF2 e CXCL2) a serem estudados mais especificamente. Essas informações contribuem para o entendimento da arquitetura genética dessa característica

Comparative study on the valorization of Sargassum from the Mexican Caribbean coast and Gulf of California as an ingredient on healthy diets for shrimp farming

Funding: This work received the financial support of the project GCRFNGR4/1388 "Algae bloom: waste resource for aquaculture and bioenergy industry in Mexico".Sargassum biomass is a potential ingredient for aquaculture formulations due to its high nutritional value and availability, as it contains a variety of essential nutrients including proteins, carbohydrates, lipids, vitamins, antioxidants, fiber, and minerals, which are essential for aquatic growing, development and health parameters including digestibility and immune response against diseases. Therefore, in this work, five experimental diets were formulated considering 2.5 % and 5 % levels of inclusion of Sargassum spp. from the Mexican Caribbean coasts (SC), and from the Gulf of California (SG), and one reference diet as a control. The characterization of the raw material and the proximal analysis of the five diets were evaluated according to standard reference methods. A 35-day feeding trial was conducted using juvenile Litopenaeus vannamei showed a shrimp survival rate of 97 ± 6 % (p > 0.05) on SC. Excellent weight gain (WG) performance of SC and SG diets at 2.5 % of inclusion resulted in >10 % WG compared to the control. The specific activity of amylase, lipase, trypsin, and chymotrypsin showed a significant increase by including Sargassum in diets, compared with the reference diet. Incorporating Sargassum at 2.5 % in feed formulations for shrimps showed a great opportunity to use it as an ingredient and improved production yields. The digestion and absorption parameters were represented by the enzymatic activity in which the diets based on Sargassum spp. from the Mexican Caribbean coast (SC) have resulted in the best performance.Publisher PDFPeer reviewe

Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart

[EN] A study has been made of the effect of chronic exercise on myocardial electrophysiological heterogeneity and stability, as well as of the role of cholinergic neurons in these changes. Determinations in hearts from untrained and trained rabbits on a treadmill were performed. The hearts were isolated and perfused. A pacing electrode and a recording multielectrode were located in the left ventricle. The parameters determined during induced VF, before and after atropine (1 mu M), were: fibrillatory cycle length (VV), ventricular functional refractory period (FRPVF), normalized energy (NE) of the fibrillatory signal and its coefficient of variation (CV), and electrical ventricular activation complexity, as an approach to myocardial heterogeneity and stability. The VV interval was longer in the trained group than in the control group both prior to atropine (78 +/- 10 vs. 68 +/- 10 ms) and after atropine (76 +/- 8 vs. 67 +/- 10 ms). Likewise, FRPVF was longer in the trained group than in the control group both prior to and after atropine (53 +/- 8 vs. 42 +/- 7 ms and 50 +/- 6 vs. 40 +/- 6 ms, respectively), and atropine did not modify FRPVF. The CV of FRPVF was lower in the trained group than in the control group prior to atropine (12.5 +/- 1.5% vs. 15.1 +/- 3.8%) and, decreased after atropine (15.1 +/- 3.8% vs. 12.2 +/- 2.4%) in the control group. The trained group showed higher NE values before (0.40 +/- 0.04 vs. 0.36 +/- 0.05) and after atropine (0.37 +/- 0.04 vs. 0.34 +/- 0.06; p = 0.08). Training decreased the CV of NE both before (23.3 +/- 2% vs. 25.2 +/- 4%; p = 0.08) and after parasympathetic blockade (22.6 +/- 1% vs. 26.1 +/- 5%). Cholinergic blockade did not modify these parameters within the control and trained groups. Activation complexity was lower in the trained than in the control animals before atropine (34 +/- 8 vs. 41 +/- 5), and increased after atropine in the control group (41 +/- 5 vs. 48 +/- 9, respectively). Thus, training decreases the intrinsic heterogeneity of the myocardium, increases electrophysiological stability, and prevents some modifications due to muscarinic block.This research was supported by the Spanish Ministry of Education and Science, (DEP2007-73234-C03-01 to AMA), http://www.mecd.gob.es/portada-mecd/; and the Generalitat Valenciana (PROMETEO 2010/093 to FJC, and FPI/2008/003 to MZ), http://www.gva.es/va/inicio/presentacion; jsessionid=ydprbDQZTsCTz85W1Such-Miquel, L.; Brines-Ferrando, L.; Alberola, A.; Zarzoso Muñoz, M.; Chorro Gasco, FJ.; Guerrero-Martínez, JF.; Parra-Giraldo, G.... (2018). Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart. 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