Ciencia y Tecnología

Density of spaces of trigonometric polynomials with frequencies from a subgroup in L∝-spaces

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Density of spaces of trigonometric polynomials with frequencies from a subgroup in L∝-spaces; Les espaces de polynômes trigonométriques avec fréquences dans un sous-groupe sont denses dans les espaces Lα Medina, Juan Miguel; Klotz, Lutz Peter; Riedel, Manfred Let G be an LCA group, H a closed subgroup, Γ the dual group of G and μ be a regular finite non-negative Borel measure on Γ. We give some necessary and sufficient conditions for the density of the set of trigonometric polynomials on Γ with frequencies from H in the space Lα(μ),α∈(0,∞).; Soit G un groupe abélien, localement compact pour une topologie séparée, H un sous-groupe fermé, Γ le groupe dual de G et μ une mesure de Borel positive ou nulle, régulière et finie sur Γ. Nous donnons des conditions nécessaires et suffisantes pour que l'ensemble des polynômes trigonométriques sur Γ avec fréquences dans H soit dense dans Lα(μ),α∈(0,∞).

An environmental magnetism approach to assess impacts of land-derived sediment disturbances on coral reef ecosystems (Cartagena, Colombia)

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An environmental magnetism approach to assess impacts of land-derived sediment disturbances on coral reef ecosystems (Cartagena, Colombia) Mejia Echeverry, Daniela; Chaparro, Marcos Adrián Eduardo; Duque Trujillo, Jose Fernando; Restrepo, Juan D. We used environmental magnetism methods to study recently deposited marine sediments from the estuarine ecosystems on the Caribbean coast of Colombia. Cartagena region has undergone an increasing sediment load during the last decades via sediment plumes from Magdalena River and its distributary man-made channel. Concentration dependent magnetic parameters show an increasing abundance of ferrimagnetic minerals on the uppermost sediments on sites located close to the continent (remanent magnetization SIRM = 5.4-9.5 × 10−3Am2 kg−1) as well as faraway sites (SIRM = 0.5-1.7 × 10−3Am2 kg−1 near Rosario Islands coral reef complex). The magnetic grain size and mineralogy along the cores are variable, showing the dominance of the magnetite-like minerals (remanent coercivity Hcr = 34.3-45.3 mT), with a minor contribution of high-coercivity minerals (Hcr = 472-588 mT). In addition, there is a moderate enrichment of elements Cu, Mo, and Zn (enrichment factor EF = 1.5-3.8) that indicates the additional land-derived contribution on sediments. The environmental magnetism approach, which shows significant signals of magnetic minerals and trace elements, is a reliable tool to prove the presence of continental sediment supply in coral reef ecosystems.

Comprehensive transcriptomic analysis of heat shock proteins in the molecular subtypes of human breast cancer

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Comprehensive transcriptomic analysis of heat shock proteins in the molecular subtypes of human breast cancer Zoppino, Felipe Carlos Martin; Guerrero Gimenez, Martin Eduardo; Castro, Gisela Natalia; Ciocca, Daniel Ramon Background: Heat Shock Proteins (HSPs), a family of genes with key roles in proteostasis, have been extensively associated with cancer behaviour. However, the HSP family is quite large and many of its members have not been investigated in breast cancer (BRCA), particularly in relation with the current molecular BRCA classification. In this work, we performed a comprehensive transcriptomic study of the HSP gene family in BRCA patients from both The Cancer Genome Atlas (TCGA) and the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) cohorts discriminating the BRCA intrinsic molecular subtypes. Methods: We examined gene expression levels of 1097 BRCA tissue samples retrieved from TCGA and 1981 samples of METABRIC, focusing mainly on the HSP family (95 genes). Data were stratified according to the PAM50 gene expression (Luminal A, Luminal B, HER2, Basal, and Normal-like). Transcriptomic analyses include several statistical approaches: differential gene expression, hierarchical clustering and survival analysis. Results: Of the 20,531 analysed genes we found that in BRCA almost 30% presented deregulated expression (19% upregulated and 10% downregulated), while of the HSP family 25% appeared deregulated (14% upregulated and 11% downregulated) (|fold change| > 2 comparing BRCA with normal breast tissues). The study revealed the existence of shared HSP genes deregulated in all subtypes of BRCA while other HSPs were deregulated in specific subtypes. Many members of the Chaperonin subfamily were found upregulated while three members (BBS10, BBS12 and CCTB6) were found downregulated. HSPC subfamily had moderate increments of transcripts levels. Various genes of the HSP70 subfamily were upregulated; meanwhile, HSPA12A and HSPA12B appeared strongly downregulated. The strongest downregulation was observed in several HSPB members except for HSPB1. DNAJ members showed heterogeneous expression pattern. We found that 23 HSP genes correlated with overall survival and three HSP-based transcriptional profiles with impact on disease outcome were recognized. Conclusions: We identified shared and specific HSP genes deregulated in BRCA subtypes. This study allowed the recognition of HSP genes not previously associated with BRCA and/or any cancer type, and the identification of three clinically relevant clusters based on HSPs expression patterns with influence on overall survival.

The reinforcement of potato cell wall as part of the phosphite-induced tolerance to UV-B radiation

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The reinforcement of potato cell wall as part of the phosphite-induced tolerance to UV-B radiation Machinandiarena, Milagros Florencia; Oyarburo, Natalia Soledad; Daleo, Gustavo Raul; Andreu, Adriana Balbina; Olivieri, Florencia Pia Phosphites (Phis), inorganic salts of phosphorous acid, have shown to be effective in protection of plants against biotic stress. Recently, we have described that potassium phosphite (KPhi) induces tolerance to UV-B radiation in potato. To counteract the harmful effect of UV radiation, plants accumulate UV-screening compounds, such as flavonoids, sinapate ester, and lignin. In previous work, we have shown an increase in guaiacol peroxidase (POD) activity in plants pretreated with KPhi and further exposed to UV-B radiation. In order to continue with this study, the expression of different enzymes and components involved in cell wall reinforcement were analyzed. An isoform of POD induced by KPhi was analyzed by isoelectric focusing and further identified as suberization-associated anionic peroxidase (POPA) by mass spectrometry. In addition, other enzymes participating in lignin biosynthesis, like caffeoyl-CoA O-methyltransferase (CCoAOMT), determined by accumulation of transcripts, and laccase activity, visualized in zymogrames, were increased by KPhi treatment previous to UV-B exposure. Further, the accumulations of extensin (EXT) transcripts and of conjugated polyamines (PAs) were increased by KPhi treatment previous to UV-B exposure. All these results suggest cell wall reinforcement in leaves due to KPhi pretreatment followed by UV-B exposure.

Las calciesferas de la Formación Vaca Muerta (Tithoniano) en la sección del arroyo Covunco, provincia del Neuquén

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Las calciesferas de la Formación Vaca Muerta (Tithoniano) en la sección del arroyo Covunco, provincia del Neuquén; Calcispheres from the Vaca Muerta Formation (Tithonian) in the Arroyo Covunco section, Neuquén province Ruffo Rey, Lautaro Julián; Kietzmann, Diego Alejandro; Bressan, Graciela Susana Se llevó adelante el estudio parataxonómico, tafonómico y bioestratigráfico de las calciesferas de la Formación Vaca Muerta (Tithoniano) en la sección del arroyo Covunco (Zapala, provincia del Neuquén). Se consideraron 215 especímenes provenientes de 20 muestras fértiles recolectadas cada 3-10 m a lo largo de 150 m de afloramiento. La asociación identificada incluye un total de 5 géneros y 8 especies (una de ellas con 2 subespecies) ya conocidas para el Tethys y la Cuenca Neuquina. Con el fin de evaluar la existencia de sesgos tafonómicos se estudiaron los efectos de la disolución y el neomorfismo sobre la pared de las calciesferas y se observó que existe variación vertical en la preservación, la cual estaría controlada principalmente por diferencias litofaciales. Esto permitió definir, por primera vez, 5 categorías de modificación tafonómica para caracterizar las asociaciones. Se identificaron cuatro bioeventos de importancia global (primeras apariciones de C. pulla, P. malmica, C. tenuis y C. fortis), que permitieron reconocer las biozonas de calciesferas de Committomiosphaera tithonica?, Parastomiosphaera malmica, Colomisphaera tenuis y Colomisphaera fortis, características del Tithoniano. Los resultados de este estudio han permitido ajustar la posición de los eventos respecto a trabajos previos en la Cuenca Neuquina.; A parataxonomic, taphonomic, and biostratigraphic study of the calcispheres from the Vaca Muerta Formation (Tithonian) was carried out at the Arroyo Covunco section (Zapala, Neuquén province). We considered 215 specimens from 20 fertile samples collected every 3-10 m along 150 m of outcrop. The identified association includes 5 genera and 8 species (with 2 subspecies) already known for the Tethyan realm and the Neuquén Basin. In order to assess the existence of taphonomic biases, the effects of dissolution and neomorphism on the calcispheres walls were analysed. Vertical variations were observed in preservation, which were related primary to lithofacial differences. This allowed defining, for the first time, 5 categories of taphonomic modification to characterize the associations. Four bioevents of global importance were identified (FOs of C. pulla, P. malmica, C. tenuis and C. fortis), allowing to recognize the typical Tithonian Committosphaera tithonica?, Parastomiosphaera malmica, Colomisphaera tenuis and Colomisphaera fortis calcisphere biozones. The results of this study have allowed to adjust the position of the events with respect to previous works in the Neuquén Basin.

Evaluación de parámetros con valor predictivo para la recuperación espermática en la biopsia testicular de pacientes con azoospermia

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Evaluación de parámetros con valor predictivo para la recuperación espermática en la biopsia testicular de pacientes con azoospermia Pirosanto, Yamila; Frattini, Gustavo; Cesari, Andreina; Meretta, Pablo Ezequiel; Pené, Alicia Proponemos la evaluación del poder predictivode parámetros clínicos y bioquímicos de pacientes,azoospérmicos como predictores del hallazgo de espermatozoidesen una biopsia testicular. Asimismoanalizaremos si en esas biopsias existe correlaciónentre los hallazgos anatomopatológicos y los del laboratoriode embriología. Metodología. Se incluyeron68 pacientes entre 22 y 61 años, atendidos enCRECER, entre los años 2006 y 2016. Se analizaronantecedentes clínicos, datos físicos, hormonales yel hallazgo de espermatozoides en biopsia testicularpor técnica abierta. Resultados. Para la hormonaFSH, el análisis arrojó un valor de AUC: 0,756 yun valor de corte: 15,85 mUI/ml. El volumen testicularmostró un valor de AUC: 0,743 y un valorde corte: 15,50 ml. Para el índice IFT, el valor deAUC fue 0,723 y el valor de corte: 2,5. Finalmente,se demostró que existe diferencia entre los hallazgosdel análisis histológico y los resultados del laboratoriode embriología (p ≤ 0,05). Conclusión. Podemossuponer que la hormona FSH, el volumen testiculary el índice IFT son buenos parámetros a considerarcuando se trata a un paciente azoospérmico. Asimismo,el laboratorio de embriología demostró ser máseficaz en la detección de espermatozoides

Rol del enterocito en la dislipidemia de la diabetes mellitus tipo 2

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Rol del enterocito en la dislipidemia de la diabetes mellitus tipo 2; Role of the enterocyte in type 2 diabetes mellitus associated dyslipidemia Closs, Cecilia I.; Ruiz Diaz, Martín A.; Diaz Cafferata, Alberto Martin; Becu, Damasia; Noqueira, Juan P. En la diabetes mellitus tipo 2 el aumento en la producción de quilomicrón en el estado post-prandial se asocia a mayor riesgo cardiovascular. La evidencia actual posiciona al enterocito como actor principal en la dislipemia de la diabetes mellitus tipo 2 debido a que aumenta la producción de apolipoproteína B-48 en respuesta a una elevación de ácidos grasos libres y glucosa. El metabolismo del quilomicrón se encuentra regulado por múltiples factores independientes además de la ingesta de grasa alimentaria. Entre estos factores se destacan las hormonas intestinales, como el péptido similar al glucagón tipo 1 que disminuye la producción de apolipoproteína B-48 y el péptido similar al glucagón tipo 2 que la aumenta. Por otro lado, la insulina inhibe de forma aguda la producción de quilomicrón en el sujeto sano mientras que en la diabetes mellitus tipo 2, este efecto está ausente. La comprensión de los factores reguladores emergentes de la secreción de quilomicrón permite vislumbrar nuevos mecanismos de control en su metabolismo y aportar estrategias terapéuticas focalizadas en la hiperlipidemia posprandial en la diabetes mellitus tipo 2 con la reducción del riesgo cardiovascular.; In type 2 diabetes mellitus there is an overproduction of chylomicron in the postprandial state that is associated with increased cardiovascular risk. Current evidence points out a leading role of enterocyte in dyslipidemia of type 2 diabetes mellitus, since it increases the production of apolipoprotein B-48 in response to a raise in plasma free fatty acids and glucose. The chylomicron metabolism is regulated by many factors apart from ingested fat, including hormonal and metabolic elements. More recently, studies about the role of gut hormones, have demonstrated that glucagon-like peptide-1 decreases the production of apolipoprotein B-48 and glucagon-like peptide-2 enhances it. Insulin acutely inhibits intestinal chylomicron production in healthy humans, whereas this acute inhibitory effect on apolipoprotein B-48 production is blunted in type 2 diabetes mellitus. Understanding these emerging regulators of intestinal chylomicron secretion may offer new mechanisms of control for its metabolism and provide novel therapeutic strategies focalized in type 2 diabetes mellitus postprandial hyperlipidemia with the reduction of cardiovascular disease risk.

Digital Cranial Endocasts of the Extinct Sloth Glossotherium robustum (Xenarthra, Mylodontidae) from the Late Pleistocene of Argentina: Description and Comparison with the Extant Sloths

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Digital Cranial Endocasts of the Extinct Sloth Glossotherium robustum (Xenarthra, Mylodontidae) from the Late Pleistocene of Argentina: Description and Comparison with the Extant Sloths Boscaini, Alberto; Iurino, Dawid A.; Sardella, Raffaele; Tirao, German Alfredo; Gaudin, Timothy; Pujos, François Roger Francis The internal cranial morphology of the terrestrial sloth Glossotherium robustum is described here based on a neurocranium from the late Pleistocene of the Pampean region of Buenos Aires, northeastern Argentina. The first published data on the morphology of the brain cavity of this species date back to the latest nineteenth century. The novel techniques of CT scanning and digital reconstructions enable non-destructive access to the internal cranial features of both extinct and extant vertebrates, and thus improve our knowledge of anatomical features that had previously remained obscure. Therefore, we performed CT scans on the posterior half of a skull of G. robustum and created digital models of the endocasts and internal structures. The results reveal the morphology of the brain cavity itself, as well as the paranasal sinuses and the trajectory of several cranial nerves and blood vessels. These features have been compared with the two extant folivoran genera, the two-toed sloth Choloepus and the three-toed sloth Bradypus. For many characteristics, especially those related to the paranasal pneumaticity and the brain cavity, a closer similarity between Glossotherium and Choloepus is observed, in accordance with the most widely accepted phylogenetic scenarios. However, other features are only shared by the two extant genera, but are probably related to allometric effects and the convergence that affected the two modern lineages. This study, which represents the first exhaustive analysis of digital endocasts of a fossil sloth, reveals the importance of the application of new methodologies, such as CT scans, for elucidating the evolutionary history of this peculiar mammalian clade.

Assessment of the Insecticidal Potential of the Eupatorium buniifolium Essential Oil Against Triatoma infestans (Hemiptera: Reduviidae). A Chiral Recognition Approach

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Assessment of the Insecticidal Potential of the Eupatorium buniifolium Essential Oil Against Triatoma infestans (Hemiptera: Reduviidae). A Chiral Recognition Approach Guerreiro, Analia Cecilia; Cecati, Francisco Miguel; Ardanaz, Carlos Enrique; Donadel, Osvaldo Juan; Tonn, Carlos Eugenio; Sosa, M.E. In this research, bioactivities toward the Chagas’ disease vector Triatoma infestans (Klug) (Hemiptera: Reduviidae) by the essential oil (EO) of Eupatorium buniifolium H. et A. (Asteraceae) are reported. The tests were designed in order to determine ovicidal activity as well as the response to vapor exposure (fumigant) and to topical application (contact toxicity) and as repellent. In the last three bioassays, nymphs from the 3rd and 4th instar were used. The assayed materials were obtained from aerial parts of plants collected during the months of March and December, throughout 4 years, in two locations. The EO samples were subjected to a qualitative analysis by GC-MS and the relative area of each component was reported by GC-FID. The main monoterpene detected was α-pinene and by using a chiral column through GC-MS experiments and having both stereoisomers as standards, we were able to determine that the enantiomer present was S,S-(−)-α-pinene. Although usually in studies of EOs changes in chemical composition are often observed due to the time of collection and the environment where the plant develops, in our case the differences were, with some exception, only at the level of the minor components. The best results were obtained in the experiments to determine ovicidal activity, fumigant action, and repellency. No worthy response was found as insecticide in the trials designed for contact toxicity. The results of the studied bioactivities were independent of the location, month, and year of collection of the plant material. This behavior provides an interesting scope in relation to the potential use of this natural blend for the control of this insect at the nymph stage as repellent as well as for decreasing the population by ovicidal effect. Notably, in the course of the two-choice repellency test, it was possible to demonstrate recognition of one of the enantiomers of the α-pinene, giving rise to a non-common chirality/response effect. In this assay, the levorotatory isomer was the most active as repellent. Considering the abundance of the wild plant under study and the fact that its EO is easy to obtain, it is suggested that it could be an adequate natural resource to control this vector in a sustainable way as a complementary approach to conventional methods.

Optimization-based design of easy-to-make devices for heat flux manipulation

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Optimization-based design of easy-to-make devices for heat flux manipulation Fachinotti, Victor Daniel; Ciarbonetti, Angel; Peralta, Ignacio; Rintoul, Ignacio In this work, we present a new method for the design of heat flux manipulating devices, with emphasis on their manufacturability. The design is obtained as solution of a nonlinear optimization problem where the objective function represents the given heat flux manipulation task, and the design variables define the material distribution in the device. In order to facilitate the fabrication of the device, the material at a given point is chosen between two materials with highly different conductivity. By this way, the whole device can be seen, in the large scale, as a metamaterial having a specific anisotropic effective conductivity. As an application example, we designed a heat flux inverter which was so simple that it could be hand-made. The performance of this device for heat flux inversion was experimentally tested, proving that it was more efficient than a more complex device designed using the classical transformation thermodynamics approach.

Active and intelligent films made from starchy sources/blackberry pulp

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Active and intelligent films made from starchy sources/blackberry pulp Gutiérrez Carmona, Tomy José Functional, active and intelligent films were prepared from biopolymeric matrices (plantain starch and pre-gelatinized plantain flour) with and without the addition of a natural filler (blackberry pulp) using the casting methodology. A thorough examination of the physicochemical, antioxidant and antimicrobial properties of the both the matrices used and the developed films was then carried out. The films developed from matrices incorporating the blackberry pulp were more amorphous, thicker, less sensitive to moisture, and with higher melting temperatures than the films made without this natural filler. The degree of substitution, average molecular weight and attenuated total reflectance Fourier transform infrared spectroscopy of the films made with blackberry pulp suggest that the starch chains were cross-linked. This is probably because the citric acid contained in the pulp functions as a cross-linking agent. Films with added blackberry pulp responded to changes in pH, i.e. were pH-sensitive, and also showed antimicrobial activity especially against Escherichia coli. In general, the addition of blackberry pulp improved the physicochemical and mechanical properties of the films developed due to cross-linking, as well as increasing their antioxidant activity.

Long-lasting isothiazolinone-based biocide obtained by encapsulation in micron-sized mesoporous matrices

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Long-lasting isothiazolinone-based biocide obtained by encapsulation in micron-sized mesoporous matrices Mardones, Lucas Emanuel; Legnoverde, María Soledad; Pereyra, Andrea Marisa; Basaldella, Elena Isabel The use of mesoporous silica materials as new hosts for stabilizing isothiazolinone-based biocides was investigated. Two types of porous matrices were synthesized: SBA-15 mesoporous silica and mesocellular siliceous foam (MCF). The physicochemical properties of the silicas (structure, textural properties) were evaluated by SEM, TEM, XRD and adsorption/desorption of N2 in order to determine their ability to encapsulate, stabilize and subsequently release a commercial biocide used for latex preservation (CMIT/MIT). CMIT/MIT consists of an aqueous solution of the active ingredients CMIT (5-chloro-2-methyl-4-isothiazolin-3-one) and MIT (2-methyl-4-isothiazolin-3-one), present in a CMIT/MIT: 3/1 wt ratio. It was observed that the biocide can be encapsulated in both silica frameworks without suffering structural damage. The SBA-15 support exhibits a lower adsorption capacity of biocide molecules than MCF, which may be attributed to both agreater MCF pore volume and pore size. MCF has less hindered diffusion causedby a short channel length, which facilitates the biocide access to the pores ofthe matrix. The long pore length of SBA-15 makes the diffusion of CMIT/MIT mixture more difficult. Biocide release tests in aqueous media indicated that the CMIT/MIT concentration in the leaching solution depends on the matrix nature, the smaller values being obtained when the ordered matrix was used. Additionally, biocide delivery could be delayed by increasing the working pH from 7 to 9. Results showed that biocide encapsulation allows maintaining a long-lasting release, even under alkaline conditions (pH 9), at which the hydrolysis of non-supported CMIT occur. Several release tests at different temperature (318, 323 and 328 K), were carried out for 20 days at pH 7. The biocide loading after the tests was reflected in the IR spectra, and it has been corroborated that biocide encapsulation allows retarding the fast thermal decomposition of CMIT.

TPACK: un modelo para analizar prácticas docentes universitarias. El caso de una docente experta

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TPACK: un modelo para analizar prácticas docentes universitarias. El caso de una docente experta; TPACK: a model to analyze university teaching practices: the case of an expert teacher Flores, Fernando Agustin Santiago; Ortiz, Margarita Cristina; Buontempo, María Paula En este artículo analizamos desde las dimensiones del modelo TPACK la praxis docente de una profesora de la asignatura Educación a Distancia de la Licenciatura en Ciencias de la Educación en el marco del proyecto: La construcción del Conocimiento Didáctico del Contenido en profesores experimentados y principiantes de una universidad del nordeste argentino. Estudio de casos múltiples.Con una perspectiva cualitativa, construimos un caso narrativo, a partir de la doble triangulación: a) de fuentes primarias- observaciones y entrevistas-,secundarias -análisis de documentos personales y curriculares-; y b) de las interpretaciones de la docente e investigadores; con el objetivo de elucidar dimensiones del TPACK en clases presenciales y entornos virtuales.Organizamos los resultados según las categorías emergentes que se detallan: status del TPACK en el conocimiento profesional docente; auto-percepción acerca del uso de las nuevas tecnologías en la asignatura; tipos y frecuencia de uso de las TIC en la enseñanza; visiones sobre los modos de integración del constructo TPACK en la praxis; características centrales de las propuestas de enseñanza y aprendizaje con tecnologías; manifestaciones del TPACK en un ciclo didáctico de la asignatura.A partir del cruce y convergencia de estas categorías y de la trayectoria y posición de la profesora en la función docente, abordamos el entramado de saberes y prácticas con características propias de la experticia docente a partir del TPACK.; In this article we analyze the teaching practice of a teacher of the subject Distance Education of the Degree in Educational Sciences, from the dimensions of the TPACK model. The framework of the article is the project: “The construction of the Pedagogical Content Knowledge in experienced and beginners teachers of the Universidad Nacional del Nordeste in Argentina. Multiple case study”.With a qualitative perspective, we build a narrative case, based on double triangulation: a) from primary sources-observations and interviews-, secondary -analysis of personal and curricular documents-; and b) the interpretations of the teacher and researchers; with the objective of identifying TPACK dimensions in face-to-face classes and virtual environments.We organize the results according to the emerging categories that are detailed: status of the TPACK in the professional knowledge of teachers; self-perception about the use of new technologies in the subject; types and frequency of use of new technologies in education; visions on the integration modes of the TPACK construct in praxis; main characteristics of the teaching and learning proposals with technologies; TPACK manifestations in the pedagogical cycle of the subject.From the convergence of these categories and the teacher’s career and position in the teaching role, we tackled the framework of knowledge and practices with characteristics of the teaching expertise from the TPACK.

The influence of magnetic field on the cold neutral medium mass fraction and its alignment with density structures

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The influence of magnetic field on the cold neutral medium mass fraction and its alignment with density structures Villagran Azuara, Marco Adrian; Gazol, A. To contribute to the understanding of the magnetic field's influence on the segregation of cold neutral medium (CNM) in the solar neighbourhood we analyse magnetohydrodynamic simulations that include themain physical characteristics of the local neutral atomic interstellar medium. The simulations have a continuous solenoidal Fourier forcing in a periodic box of 100 pc per side and an initial uniform magnetic field (B 0 ) with intensities ranging between ~0.4 and ~8 μG. Our main results are as follows. (i) The CNM mass fraction diminishes with the increase in magnetic field intensity. (ii) There is a preferred alignment between CNM structures and B in all our B 0 range but the preference weakens as B 0 increases. It is worth noticing that this preference is also present in two-dimensional projections making an extreme angle (0 or π/2) with respect to B 0 and it is only lost for the strongest magnetic field when the angle of projection is perpendicular to B 0 . (iii) The aforementioned results are prevalent despite the inclusion of self-gravity in our continuously forced simulations with a mean density similar to the average value of the solar neighbourhood. (iv) Given a fixed B 0 and slightly higher mean densities, up to double, the effects of self-gravity are still not qualitatively significant.

¿Una educación estética de la subjetividad democrática?

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¿Una educación estética de la subjetividad democrática?; An esthetic education of democratic subjectivity? Prestifilippo, Agustín Lucas En este artículo analizamos las dimensiones de la significación que puede asumir el arte, y su experiencia, para la formación de la subjetividad democrática. A partir de algunos resultados de estudios de sociología empírica, indagamos el modo en que la teoría social crítica de Adorno interpreta la actitud de rechazo a la experiencia estética que se observa en algunas ideologías vigentes en el mundo contemporáneo. Si, según esta perspectiva, los individuos “carentes de musa” son también aquellos que suelen expresar afirmaciones de agresividad ante la diferencias culturales y una actitud de sumisión irreflexiva a la autoridad moral, de eso puede desprenderse no solamente la pregunta acerca de la afinidad entre experiencia estética y cultura política, sino también si la experiencia estética carga con una fuerza capaz de “educar” a la subjetividad democrática en el sentido de la emancipación. Para responder a esta pregunta, diferenciamos distintos modos de interpretar los efectos en el sujeto práctico que suscita la experiencia del arte. Finalmente, presentamos algunas conclusiones relativas al interés ético-político del arte en la indagación acerca de los prejuicios que ordenan nuestras valoraciones morales, económicas y políticas.; In this paper we analyze the dimensions of the meaning that Art and its experience can assume to configure the democratic subjectivity. Based on some results of empirical sociology studies, we question how Adorno`s Social Critical Theory understands the attitude of rejection of the esthetical experience, which is observed in some of the current ideologies of the contemporary world. If, according to this perspective, individuals “lacking Muse” are also those who express statements of aggressiveness in front of cultural differences and an attitude of a non-reflective submission facing moral authority, then it is possible to deduce not only the question about the affinity between esthetical experience and political culture, but also the question if esthetical experience carries a force capable of “educating” subjectivity in the sense of Democracy. In order to answer these questions, we differentiate ways of interpreting the effects on the subject of praxis of the aesthetical experience. Finally, we present some conclusions related to the ethical-political interest of art in the inquiry on the prejudices that organize our moral, economic and political valuations.

Demócratas insatisfechos: un estudio sobre actitudes hacia la democracia en Córdoba (Argentina)

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Demócratas insatisfechos: un estudio sobre actitudes hacia la democracia en Córdoba (Argentina); Dissatisfied democrats: a study of democratic attitudes in Argentinian citizens Alonso, Daniela Rocío; Brussino, Silvina Alejandra; Civalero Gottero, Luciana María Este trabajo propone un abordaje de las actitudes ciudadanas hacia la democracia y el rol de aspectos psicosociales en su análisis. De modo específico, se estudiaron las diferencias en las actitudes hacia la democracia respecto a tres dimensiones relacionadas: preferencia por el régimen político democrático, valoración de la democracia como ideal y satisfacción con el funcionamiento de la democracia. Además, se analizó la contribución de los valores psicosociales, el autoposicionamiento ideológico, la tolerancia a la corrupción política, evaluación de los actores políticos, participación política y aspectos sociodemográficos a la explicación de estas dimensiones de las actitudes hacia la democracia. Para ello, se tomó una muestra de 252 ciudadanos de Córdoba (AR), de entre 18 y 65 años, a través de un muestro cuotificado por edad, sexo y nivel socioeconómico. Los datos se recogieron mediante un cuestionario cerrado en formato papel y, para su análisis, se hicieron pruebas de diferencia de medias y análisis de regresión múltiple. Los resultados permitieron dar cuenta de que los ciudadanos realizan evaluaciones diferenciales de la democracia como sistema político abstracto y de su capacidad de brindar resultados deseables. Se discute el rol de las variables estudiadas en las evaluaciones sobre democracia, destacando la importancia de aspectos ideológicos y normativos.; This article access citizens’ attitudes towards democracy and the role that psycho-social aspects play on their explanation. Specifically, differences in attitudes towards democracy based on three related dimensions are studied: preference for a democratic political system, evaluation of democracy as an ideal and satisfaction with the functioning of democracy. In addition, we address the contribution of psychosocial values, ideology, tolerance of political corruption, evaluation of political actors, political participation and socio-demographic aspects to the explanation of these three dimensions of attitudes toward democracy. We selected a sample of 252 citizens of Córdoba (AR), between 18 and 65 years old, through sampling with age, sex and socioeconomic status quotification. Data was collected through the application of a closed questionnaire and mean difference tests and multiple regression analysis were performed. The results evidenced that citizens make differential assessments of democracy as an ideal and about its ability to provide desirable results. The role of the variables studied in relation to the different assessments of democracy is discussed, highlighting the importance of ideological and normative aspects.

Membrane-shed vesicles from the parasite Trichomonas vaginalis: characterization and their association with cell interaction

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Membrane-shed vesicles from the parasite Trichomonas vaginalis: characterization and their association with cell interaction Nievas, Yésica Romina; Cóceres, Verónica Mabel; Midlej, Victor; de Souza, Wanderley; Benchimol, Marlene; Pereira Neves, Antonio; Vashisht, Ajay A.; Wohlschlegel, James A.; Johnson, Patricia J.; de Miguel, Natalia Trichomonas vaginalis is a common sexually transmitted parasite that colonizes the human urogenital tract, where it remains extracellular and adheres to epithelial cells. Infections range from asymptomatic to highly inflammatory, depending on the host and the parasite strain. Despite the serious consequences associated with trichomoniasis disease, little is known about parasite or host factors involved in attachment of the parasite-to-host epithelial cells. Here, we report the identification of microvesicle-like structures (MVs) released by T. vaginalis. MVs are considered universal transport vehicles for intercellular communication as they can incorporate peptides, proteins, lipids, miRNA, and mRNA, all of which can be transferred to target cells through receptor–ligand interactions, fusion with the cell membrane, and delivery of a functional cargo to the cytoplasm of the target cell. In the present study, we demonstrated that T. vaginalis release MVs from the plasma and the flagellar membranes of the parasite. We performed proteomic profiling of these structures demonstrating that they possess physical characteristics similar to mammalian extracellular vesicles and might be selectively charged with specific protein content. In addition, we demonstrated that viable T. vaginalis parasites release large vesicles (LVs), membrane structures larger than 1 µm that are able to interact with other parasites and with the host cell. Finally, we show that both populations of vesicles present on the surface of T vaginalis are induced in the presence of host cells, consistent with a role in modulating cell interactions.

Comments on Digital Current Control in a Rotating Reference Frame-Part I: System Modeling and the Discrete Time-Domain Current Controller With Improved Decoupling Capabilities

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Comments on Digital Current Control in a Rotating Reference Frame-Part I: System Modeling and the Discrete Time-Domain Current Controller With Improved Decoupling Capabilities Busada, Claudio Alberto; Gómez Jorge, Sebastián; Solsona, Jorge Alberto A recent paper presents a discrete time model in a rotating dq reference frame of an R-L filter, and its current control. The purpose of this note is: 1) To show that the discrete model presented in the paper behaves differently to the sampled continuous time model of the plant, formulated in the stationary reference frame. 2) To find the proper discretization of the plant in dq coordinates. 3) To verify that there is cross coupling between axis d and q in the closed loop system if the original model is used, and that this coupling is not present when using the model found in this note. In the note it is verified that having a precise model of the plant allows to fulfill the control objective of obtaining the complete decoupling between axis.

Effect of milk production on reproductive performance in dairy herds

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Effect of milk production on reproductive performance in dairy herds Rearte, R.; LeBlanc, S. J.; Corva, S. G.; de la Sota, Rodolfo Luzbel; Lacau, Isabel María; Giuliodori, M. The objective of the present study was to assess the relationship between individual cow milk yield and fertility, accounting for the contextual effect of the herd. A dataset including 657,968 lactations from 677 dairy herds in Argentina from 2001 to 2012 was used. The odds of pregnancy by 100 DIM were assessed by a multilevel logistic model (with cow as the first and herd as the second hierarchical level), and time to pregnancy by a proportional hazards regression model. Multilevel logistic models included the fixed effects of milk yield by 80 DIM, parity, year and calving season at cow level and quartiles of herd milk yield by 80 DIM as a contextual effect. The proportional hazards model included the effect of daily milk yield as time dependent variable and herd-level milk yield as stratification variable. Cows producing 1 SD (400 kg) over the mean milk yield of their herd had 1.0 percentage points lower pregnancy by 100 DIM (from 31.4% to 30.4%, odds ratio (OR) = 0.942) when in herds in the top quartile of milk yield, whereas they increased 0.4 percentage points (from 27.9 to 28.3%) when in herds in the lowest quartile of milk yield. Only 4% of the observed variation in pregnancy by 100 DIM was explained by the random effect of the herd. Similarly, cows producing 1 SD (8 kg/d) greater than the herd daily milk had 1.3% lower hazard of pregnancy (hazard ratio (HR) = 0.987) at 63 DIM in herds in the top quartile of milk yield whereas they had 14.8% higher hazard (HR = 1.148) in herds in the lowest quartile of milk yield. The magnitude of the negative association between the cow´s daily milk yield and the hazard of pregnancy increased with DIM.In conclusion, the relationship between milk yield and reproductive performance is statistically significant but the effect size is practically small, it is modulated by herd productivity.

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