4,542 research outputs found
DISTRIBUTION OF PIGMENT CELLS IN THE HEART OF THE RABBITFISH, CHIMAERA MONSTROSA (CONDRICHTHYES: HOLOCEPHALI)
El resumen aparece en el Program & Abstracts of the 10th International Congress of Vertebrate Morphology, Barcelona 2013. Anatomical Record, Volume 296, Special Feature — 1: P-076.The study of extracutaneous cells producing and storing melanin is of interest because it
may provide valuable information about the presence of neural crest elements in internal
organs and tissues. Here we report, for the first time, the presence and distribution of
melanophores in the heart of a chondrichthyan species, the rabbitfish, Chimaera
monstrosa. Pigment cells were found in all of 20 hearts examined. Pigment cells occur
mainly in the cardiac outflow tract, which consists of two anatomical components, the
proximal, myocardial conus arteriosus and the distal, non-myocardial bulbus arteriosus.
A few groups of dark pigmented cells were found in the apex of the ventricle of one
specimen and in the atrium of two specimens. In all instances, the melanophores were
located in the subepicardial space, where they could be well recognized in both
unstained and stained histological sections. The distribution and intensity of the
pigmentation in the cardiac outflow tract varies markedly between individuals. In all
cases, however, the pigmented area is larger on the dorsal than on the ventral surface.
Dorsally, the size of the pigmented area ranges from a fringe that includes the bulbus
and the distal part of the conus to the whole surface of the outflow tract. Ventrally, the
pigmented area does not cover the entire conus arteriosus. The intensity of the
pigmentation also varies widely; in general, it is highest at the distal portion of the conus.
There is no relationship between the distribution and intensity of the pigmentation and
the sex and age of the animals. The functional role of the pigmented cells is unknown. If
the melanophores in the heart of C. monstrosa are indeed of neural crest origin, it would
suggest a notable contribution of the neural crest cells to the cardiac outflow tract in
holocephalans.Proyecto CGL2010-16417/BOS; Fondos FEDER
BES-2011-04690
Lowest thermal transmittance of an external wall under budget,material and thickness restrictions: An integer linear programming approach
[EN] This paper deals with the minimization of a building¿s external wall thermal transmittance, with theaim of improving the energy efficiency of the building. The wall¿s thermal transmittance must abide bythe current legislation, but also suit the limitations of other construction parameters, mainly budget andthickness, but also time limit, workforce, number and thickness of the layers and availability of materialsdepending on the approach.The optimization is achieved formulating an Integer Linear Programming (ILP) problem involving theparameters mentioned above. Therefore, any available ILP solver can be run to obtain the best combinationof the different materials and thicknesses for the layers, in order to minimize the thermal transmittance.This paper presents a case study of a common but representative external wall consisting of 6 layers,with more than 670,000 possible combinations of materials and their thicknesses. The study concludeswith a comparison of the lowest thermal transmittance obtained for a selection of budget and thicknesscombinations for the mentioned wall.This work was partially supported by the "Ministerio de Economia y Competitividad, Programa Estatal de Investigacion, Desarrollo e Innovacion 582 Orientada a los Retos de la Sociedad, Proyectos I+D+I 2014", Spain, under Grant TEC2014-52690-R.Soler Fernández, D.; Salandin, A.; Micó, JC. (2018). Lowest thermal transmittance of an external wall under budget,material and thickness restrictions: An integer linear programming approach. Energy and Buildings. 158:222-233. https://doi.org/10.1016/j.enbuild.2017.09.078S22223315
Identification of a novel plant-derived attractant for Acromyrmex lobicornis leaf-cutting ants
Leaf-cutting ants are considered major pests of agriculture and forestry in the Neotropics. Attractive toxic baits are the prevailing method for managing them. Thus, there is great interest in identifying attractants to incorporate into these baits. Moreover, leaf-cutting ants can avoid toxic baits by associating the attractant with the toxin. We evaluated attractiveness of heptyl butyrate, a volatile compound found in fresh apples and plums. We conducted field experiments with ten colonies of Acromyrmex lobicornis. First, we evaluated the behaviour of ants exposed to heptyl butyrate at 1% by surrounding resources. Then, we compared the attractiveness of heptyl butyrate and orange pulp, the most commonly used attractant. Finally, we evaluated whether heptyl butyrate increases the attractiveness of a carbohydrate resource at varying doses. Heptyl butyrate at 1% attracted 92% more ants than the control and that it was as attractive as orange pulp. Heptyl butyrate paired with sucrose at concentrations of 0.001 and 0.1% was more attractive than sucrose alone, but greater concentrations did not increase sucrose’s attractiveness. Therefore, heptyl butyrate could be added to toxic baits to manage A. lobicornis as it is as attractive as the most commonly used attractant and can be applied directly to the pellets.Fil: Alma, Andrea Marina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Fernández, Patricia C.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Norte. Estación Experimental Agropecuaria Delta del Paraná; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Biología Aplicada y Alimentos. Cátedra de Química de Biomoléculas; ArgentinaFil: Perri, Daiana Vanesa. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Biología Aplicada y Alimentos. Cátedra de Química de Biomoléculas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Buteler, Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin
Proinflammatory response of canine trophoblasts to <i>Brucella canis</i> infection
Brucella canis infection is an important cause of late-term abortion in pregnant bitches. The pathophysiological mechanisms leading to B. canis–induced abortion are unknown, but heavily infected trophoblasts are consistently observed. As trophoblasts responses to other pathogens contribute to placental inflammation leading to abortion, the aim of the present study was to characterize the cytokine response of canine trophoblasts to B. canis infection. To achieve this, trophoblasts isolated from term placenta of healthy female dogs were infected with B. canis, culture supernatants were harvested for cytokine determinations, and the load of intracellular viable B. canis was determined at different times post-infection. Additionally, cytokine responses were assessed in non-infected trophoblasts stimulated with conditioned media (CM) from B. canis-infected canine monocytes and neutrophils. Finally, cytokine response and bacteria replication were assessed in canine placental explants infected ex vivo. B. canis successfully infected and replicated in primary canine trophoblasts, eliciting an increase in IL-8 and RANTES (CCL5) secretion. Moreover, the stimulation of trophoblasts with CM from B. canis-infected monocytes and neutrophils induced a significant increase in IL-8, IL-6 and RANTES secretion. B. canis replication was confirmed in infected placental explants and the infection elicited an increased secretion of TNF-α, IL-8, IL-6 and RANTES. This study shows that canine trophoblasts produce proinflammatory cytokines in response to B. canis infection and/or to stimulation with factors produced by infected monocytes and neutrophils. These cytokines may contribute to placental inflammation leading to abortion in B. canis-infected pregnant bitches.Instituto de Estudios Inmunológicos y Fisiopatológico
Proinflammatory response of canine trophoblasts to <i>Brucella canis</i> infection
Brucella canis infection is an important cause of late-term abortion in pregnant bitches. The pathophysiological mechanisms leading to B. canis–induced abortion are unknown, but heavily infected trophoblasts are consistently observed. As trophoblasts responses to other pathogens contribute to placental inflammation leading to abortion, the aim of the present study was to characterize the cytokine response of canine trophoblasts to B. canis infection. To achieve this, trophoblasts isolated from term placenta of healthy female dogs were infected with B. canis, culture supernatants were harvested for cytokine determinations, and the load of intracellular viable B. canis was determined at different times post-infection. Additionally, cytokine responses were assessed in non-infected trophoblasts stimulated with conditioned media (CM) from B. canis-infected canine monocytes and neutrophils. Finally, cytokine response and bacteria replication were assessed in canine placental explants infected ex vivo. B. canis successfully infected and replicated in primary canine trophoblasts, eliciting an increase in IL-8 and RANTES (CCL5) secretion. Moreover, the stimulation of trophoblasts with CM from B. canis-infected monocytes and neutrophils induced a significant increase in IL-8, IL-6 and RANTES secretion. B. canis replication was confirmed in infected placental explants and the infection elicited an increased secretion of TNF-α, IL-8, IL-6 and RANTES. This study shows that canine trophoblasts produce proinflammatory cytokines in response to B. canis infection and/or to stimulation with factors produced by infected monocytes and neutrophils. These cytokines may contribute to placental inflammation leading to abortion in B. canis-infected pregnant bitches.Instituto de Estudios Inmunológicos y Fisiopatológico
La educación intercultural bilingüe: Nociones e iniciativas fundadas en los derechos personalísimos
A nivel general, la educación en la República Argentina ha sido concebida y desarrollada desde una perspectiva esencialmente etnocentrista. En este sentido, se ha privilegiado y transmitido una visión del mundo basada en valores occidentales. Si bien se procura brindar al alumnado nociones teóricas y prácticas respecto de la pluralidad cultural, difícilmente pueda afirmarse que cada grupo social —o con identidad cultural propia— accede actualmente a un modelo educativo exclusivamente propio, o al menos respetuoso de sus normas, tradiciones y costumbres. Lo enunciado adquiere relevancia práctica cuando el foco es puesto en los Pueblos Originarios que habitan el territorio nacional e integran nuestra sociedad. En tal sentido, los alumnos indígenas insertos en el sistema educativo actual se enfrentan a la dificultad de tener que adaptarse a un lenguaje, hábitos y métodos de aprendizaje que pueden resultarles ajenos, sin mencionar los roles usualmente asignados en los ámbitos laborales y otros, sean públicos o privados.Fil: Fernández, Andrea C.. Universidad de Buenos Aires. Facultad de Derecho; ArgentinaFil: Lopez Viñals, Joaquin. Universidad Nacional de Tucuman. Facultad de Derecho y Cs.sociales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Deep Convolutional Autoencoders as Generic Feature Extractors in Seismological Applications
The idea of using a deep autoencoder to encode seismic waveform features and
then use them in different seismological applications is appealing. In this
paper, we designed tests to evaluate this idea of using autoencoders as feature
extractors for different seismological applications, such as event
discrimination (i.e., earthquake vs. noise waveforms, earthquake vs. explosion
waveforms, and phase picking). These tests involve training an autoencoder,
either undercomplete or overcomplete, on a large amount of earthquake
waveforms, and then using the trained encoder as a feature extractor with
subsequent application layers (either a fully connected layer, or a
convolutional layer plus a fully connected layer) to make the decision. By
comparing the performance of these newly designed models against the baseline
models trained from scratch, we conclude that the autoencoder feature extractor
approach may only perform well under certain conditions such as when the target
problems require features to be similar to the autoencoder encoded features,
when a relatively small amount of training data is available, and when certain
model structures and training strategies are utilized. The model structure that
works best in all these tests is an overcomplete autoencoder with a
convolutional layer and a fully connected layer to make the estimation
Fibrilación auricular paroxística oculta en pacientes con ictus criptogénico estudiados con Holter implantado: prevalencia y factores predictores
La fibrilación auricular paroxística oculta (FAPO) es una causa frecuente de ictus criptogénico (IC), que permanece sin detectar si no se emplea monitorización prolongada del electrocardiograma (ECG), quedando los pacientes con una prevención secundaria inadecuada. El Holter implantable es una opción útil para la detección de FAPO en IC. Sin embargo, no se han definido las principales variables que permitan una selección óptima de los pacientes candidatos al implante, así como el tiempo necesario de seguimiento. Nuestros objetivos fueron conocer la prevalencia de FAPO en los pacientes con IC estudiados mediante Holter implantable a largo plazo y seleccionar entre sus variables basales aquellas que resulten predictoras para una futura detección de FAPO.Grado en Medicin
A General Limitation on Monte Carlo Algorithms of Metropolis Type
We prove that for any Monte Carlo algorithm of Metropolis type, the
autocorrelation time of a suitable ``energy''-like observable is bounded below
by a multiple of the corresponding ``specific heat''. This bound does not
depend on whether the proposed moves are local or non-local; it depends only on
the distance between the desired probability distribution and the
probability distribution for which the proposal matrix satisfies
detailed balance. We show, with several examples, that this result is
particularly powerful when applied to non-local algorithms.Comment: 8 pages, LaTeX plus subeqnarray.sty (included at end),
NYU-TH-93/07/01, IFUP-TH33/9
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