279 research outputs found

    Electromagnetic Composites: from Effective Medium Theories to Metamaterials

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    Electromagnetic (EM) composites have stimulated tremendous fundamental and practical interests owing to their flexible electromagnetic properties and extensive potential engineering applications. Hence, it is necessary to systematically understand the physical mechanisms and design principles controlling EM composites. In this tutorial, we first provide an overview of the basic theory of electromagnetism about electromagnetic constitutive parameters that can represent the electromagnetic properties of materials. We show how this corpus allows a consistent construction of effective medium theories and allows for numerical simulation of EM composites to deal with structure-property relationships. We then discuss the influence of spatial dispersion of shaped inclusions in the material medium on the EM properties of composites, which has not been systematically illustrated in the context of this interdisciplinary topic. Next, artificial composites or metamaterials with peculiar properties not readily available in nature are highlighted with particular emphasis on the control of the EM interaction with composites. We conclude by discussing appropriate methods of electromagnetic measurement and practical aspects for implementing composites for specific applications are described. Overall, this tutorial will serve the purpose of introducing the basics and applications of electromagnetic composites to newcomers in this field. It is also anticipated that researchers from different backgrounds including materials science, optics, and electrical engineering can communicate to each other with the same language when dealing with this interdisciplinary subject and further push forward this advancement from fundamental science to technological applications.Comment: 63 pages, 20 figure

    Filling the Gaps to Solve the Extensin Puzzle

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    Extensins (EXTs) are highly repetitive plant O-glycoproteins that require several post-translational modifications (PTMs) to become functional in plant cell walls. First, they are hydroxylated on contiguous proline residues; then they are O-glycosylated on hydroxyproline and serine. After secretion into the apoplast, O-glycosylated EXTs form a tridimensional network organized by inter- and intra-Tyr linkages. Recent studies have made significant progress in the identification of the enzymatic machinery required to process EXTs, which includes prolyl 4-hydroxylases, glycosyltransferases, papain-type cysteine endopeptidases, and peroxidases. EXTs are abundant in plant tissues and are particularly important in rapidly expanding root hairs and pollen tubes, which grow in a polar manner. Small changes in EXT PTMs affect fast-growing cells, although the molecular mechanisms underlying this regulation are unknown. In this review, we highlight recent advances in our understanding of EXT modifications throughout the secretory pathway, EXT assembly in cell walls, and possible sensing mechanisms involving the Catharanthus roseus cell surface sensor receptor-like kinases located at the interface between the apoplast and the cytoplasmic side of the plasma membrane. This review describes recent progress in our understanding of extensin post-translational modifications throughout the secretory pathway, extensin secretion and assembly in the cell walls, and possible sensing mechanisms at the interface between the apoplast and the cytoplasmic side of the cell surface.Fil: Marzol, Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Borassi, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Bringas, Mauro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Sede, Ana Rocío. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Rodríguez Garcia, Diana Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Capece, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Estevez, Jose Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentin

    Applied microbiology on poultry industry: from nutrition to the gut microbiota

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    Poultry products (i.e., meat and eggs) are one of the major protein sources for the human diet. The animal’s diet is one of the key elements that the poultry industry has been focused on, to improve the animal’s performance, maintaining their healthy growth and, ultimately, high quality end products. The incorporation of functional ingredients in feed formulations, aiming to provide extra benefits and/or prevent diseases, has been considered efficient in maintaining the animal’s productivity and simultaneously ensure its well-being. Nutrient’s bioavailability varies throughout digestion and absorption within the poultry’s gastrointestinal tract (GIT). A reliable in vitro model, as the one developed and used in this study, capable of mimicking all digestion, absorptive and cecal fermentation processes, is a useful tool to study the potential benefits of feed supplemented with functional and/or bioactive ingredients. The developed in vitro gastrointestinal model simulates the chemical, enzymatic, and mechanical conditions prevailing in the chicken´s GIT, from beak to cecum. Fresh broiler’s cecal samples were used as inoculum for batch cecal fermentation and the impact of different feed formulations, on bacteria modulation, organic acids, and total ammonia nitrogen production, were assessed. Overall, this approach enables to evaluate, as close to reality as possible, the potential of target additives, providing a trustworthy tool for the development of functional feeds.info:eu-repo/semantics/acceptedVersio

    Strategies to assess the impact of sustainable functional food ingredients on gut microbiota

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    Nowadays, it is evident that food ingredients have different roles and distinct health benefits to the consumer. Over the past years, the interest in functional foods, especially those targeting gut health, has grown significantly. The use of industrial byproducts as a source of new functional and sustainable ingredients as a response to such demands has raised interest. However, the properties of these ingredients can be affected once incorporated into different food matrices. Therefore, when searching for the least costly and most suitable, beneficial, and sustainable formulations, it is necessary to understand how such ingredients perform when supplemented in different food matrices and how they impact the host's health. As proposed in this manuscript, the ingredients' properties can be first evaluated using in vitro gastrointestinal tract (GIT) simulation models prior to validation through human clinical trials. In vitro models are powerful tools that mimic the physicochemical and physiological conditions of the GIT, enabling prediction of the potentials of functional ingredients per se and when incorporated into a food matrix. Understanding how newly developed ingredients from undervalued agro-industrial sources behave as supplements supports the development of new and more sustainable functional foods while scientifically backing up health-benefits claims.info:eu-repo/semantics/publishedVersio

    Supporting information for National, regional, and worldwide estimates of low birthweight rates in 2015, with trends from 2000: a systematic analysis

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    Data produced by the World Health Organization, UNICEF, LSHTM and Johns Hopkins University to estimate national low birthweight (LBW) and numbers for 195 countries. LBW data was collated through a systematic review of national routine/registration systems, nationally representative surveys, and other data sources, and subsequently modelled using restricted maximum likelihood estimation with country-level random effects. Data includes a list of 1447 rate data points used as an input to the modelled estimates, yearly national-level covariates for each of the 195 countries studied from 2000 to 2015, and information on estimated low birthweight rates from 2000 to 2015 for 148 countries with data. Stata code used to generate these estimates is provided

    Human Q fever in Spain (2016-2020)

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    Artículo BES V.31N.1Introducción: La fiebre Q es una antropozoonosis causada por Coxiella burnetii. una bacteria extremadamente resistente a condiciones medioambientales adversas. Se transmite por vía aérea de animales a personas y, en España, país que más casos anuales notifica a Europa, los reservorios principales son los rumiantes domésticos. Método: Análisis epidemiológico descriptivo de los casos de fiebre Q notificados a la Red Nacional de Vigilancia Epidemiológica (RENAVE) entre 2016 y 2020 en 45 provincias. Se analizaron variables temporales y espaciales. Análisis espacial en las zonas de mayor incidencia y cálculo del riesgo relativo suavizado (RRs) por municipio. Resultados: 1749 casos totales, de los cuales1249 son hombres (71,2%). La mayoría se producen entre los 35 y los 55 años. La incidencia aumenta de marzo a junio. La distribución espacial es heterogénea y se concentra en las Islas Canarias, el País Vasco, La Rioja, Navarra y Andalucía Occidental. Las zonas más afectadas tienen patrones espaciales con distintos niveles de RRs. En Canarias el RRs parece superior en las islas orientales. En las provincias del norte peninsular es superior las provincias occidentales. En Andalucía y Badajoz es mayor en el sureste de Badajoz y norte de Sevilla. Conclusiones: La situación epidemiológica de la fiebre Q parece mantenerse estable. La infección es más frecuente en varones en edades medias. El aumento de casos en primavera puede relacionarse con el ciclo reproductivo del ganado. Factores ambientales pueden condicionar la distribución espacial. Dado el carácter zoonótico y geográfico-estacional, serán necesarios futuros estudios orientados desde una perspectiva Una Salud.N

    Mating, but Not Male Accessory Gland Products, Changes Female Response to Olfactory Cues in Anastrepha Fruit Flies

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    Copulation and/or ejaculate components can alter female physiological state and female post-mating behavior. The objective of the present study was to determine if copulation and male reproductive accessory gland products (MAGs) modify the behavior of female Anastrepha ludens (Loew) and Anastrepha obliqua (Macquart; Diptera: Tephritidae) in response to two stimuli: male-emitted pheromone and oviposition host volatiles. Olfactometry studies revealed that mated females of both A. ludens and A. obliqua have a stronger response for host volatiles compared to unmated females, which have a stronger response for male pheromone. We also examined olfactory responses of females mated to testectomized males who could transfer MAGs but not sperm. In both species, MAGs alone did not cause the change in the olfactory response observed after copulation, unlike what has been found in Ceratitis capitata (Wiedemann). Females mated to testectomized males responded equally to the male sex pheromone or to host volatiles, thus suggesting that the whole ejaculate is needed to elicit the complete behavioral switch in olfactory response. The function of MAGs is still unknown in these two pests of economic importance. The response for host volatiles by mated females has implications for the development of baits and traps that should preferably attract and target this population.Fil: Córdova García, Guadalupe. Universidad Veracruzana; MéxicoFil: Sirot, Laura. The College Of Wooster; Estados UnidosFil: Abraham, Solana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Díaz Fleischer, Francisco. Universidad Veracruzana; MéxicoFil: Flores Estevez, Norma. Universidad Veracruzana; MéxicoFil: López Ortega, Maurilio. Universidad Veracruzana; MéxicoFil: Pérez Staples, Diana. Universidad Veracruzana; Méxic
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