CONICET Digital

Conformal Killing-Yano 2-forms

Conformal Killing-Yano 2-forms Dotti, Isabel Graciela; Andrada, Adrián Marcelo Riemannian manifolds carrying 2-forms satisfying the Killing-Yano equation and the conformal Killing-Yano equation are natural generalizations of nearly Kähler and Sasakian manifolds. In this article we exhibit new solutions of these equations. We also provide obstructions for their existence on Lie groups, and reduce the study of conformal Killing-Yano 2-forms to a particular class of non degenerate Killing-Yano 2-forms.

La verdad burocratizada: las condiciones materiales de vida de los internos en la Penitenciaría de Córdoba entre 1908 y 1916

La verdad burocratizada: las condiciones materiales de vida de los internos en la Penitenciaría de Córdoba entre 1908 y 1916; The bureaucratized truth: the material conditions of life of the inmates in the Córdoba Prison between 1908 and 1916 Luciano, Milena Este artículo aborda los lineamientos establecidos en la documentación oficial con respecto a las condiciones de alimentación, vestuario e higiene de los presos de la Penitenciaria de Córdoba. Específicamente analizamos la relación entre las versiones difundidas en el discurso oficial y las denuncias efectuadas por parte de los medios de prensa locales, durante la gestión de Antonio Amaya (1908 – 1916). Por último recuperamos la sublevación ocurrida en el penal en mayo de 1916, como acontecimiento central que, con la destitución de su director, cristalizó las contradicciones existentes al interior de la Penitenciaría.; This article addresses the guidelines established in the official documentation regarding the feeding, clothing and hygiene conditions of the prisoners in the Córdoba Prison. Specifically, we analyze the relationship between the versions disseminated in the official speech and the denunciations made by the local press during the administration of Antonio Amaya (1908 - 1916). Finally we recover the riot that took place in the prison in May 1916, as a central event that caused the dismissal of its director, crystallized the contradictions existing inside the prison.

Developing a novel paper-based enzymatic biosensor assisted by digital image processing and first-order multivariate calibration for rapid determination of nitrate in food samples

Developing a novel paper-based enzymatic biosensor assisted by digital image processing and first-order multivariate calibration for rapid determination of nitrate in food samples Jalalvand, Ali R.; Mahmoudi, Majid; Goicoechea, Hector Casimiro For the first time, a novel analytical method based on a paper based enzymatic biosensor assisted by digital image processing and first-order multivariate calibration has been reported for rapid determination of nitrate in food samples. The platform of the biosensor includes a piece of Whatman filter paper impregnated with Griess reagent (3-nitroaniline, 1-naphthylamine and hydrochloric acid) and nitrate reductase. After dropping a distinct volume of nitrate solution onto the biosensor surface, nitrate reductase selectively reduces nitrate to nitrite and then the Griess reagent selectively reacts with nitrite to produce a red colored azo dye. Therefore, the color intensity of the produced azo dye is correlated with nitrate concentration. After image capture, the images were processed and digitized in the MATLAB environment by the use of an image processing toolbox and the vectors produced by the digital image processing step were used as inputs of the first-order multivariate calibration algorithms. Several multivariate calibration algorithms and pre-processing techniques have been used to build multivariate calibration models for verifying which technique offers the best predictions towards nitrate concentrations in synthetic samples and the best algorithm has been chosen for nitrate determination in potato, onion, carrot, cabbage and lettuce samples as real cases.

UV-B radiation delays flowering time through changes in the PRC2 complex activity and miR156 levels in Arabidopsis thaliana

UV-B radiation delays flowering time through changes in the PRC2 complex activity and miR156 levels in Arabidopsis thaliana Dotto, Marcela Claudia; Gomez, Maria Sol; Soto, María Soledad; Casati, Paula UV-B is a high-energy component of the solar radiation perceived by the plant and induces a number of modifications in plant growth and development, including changes in flowering time. However, the molecular mechanisms underlying these changes are largely unknown. In the present work, we demonstrate that Arabidopsis plants grown under white light supplemented with UV-B show a delay in flowering time, and this developmental reprogramming is mediated by the UVR8 photoreceptor. Using a combination of gene expression analyses and UV-B irradiation of different flowering mutants, we gained insight into the pathways involved in the observed flowering time delay in UV-B-exposed Arabidopsis plants. We provide evidence that UV-B light downregulates the expression of MSI1 and CLF, two of the components of the polycomb repressive complex 2, which in consequence drives a decrease in H3K27me3 histone methylation of MIR156 and FLC genes. Modification in the expression of several flowering time genes as a consequence of the decrease in the polycomb repressive complex 2 activity was also determined. UV-B exposure of flowering mutants supports the involvement of this complex in the observed delay in flowering time, mostly through the age pathway.

A responsible fiscal system for Latin America is possible: Dogmatic bases and basic premises constitutive

A responsible fiscal system for Latin America is possible: Dogmatic bases and basic premises constitutive Rezzoagli, Luciano Carlos Effective government action to alleviate social inequalities and boost economic growth, from the strict tax orbit, is a task consciously rejected by theparliament and government. Indeed, they subordinate inclusive public policies, almost exclusively, from "non-commercial" forms, such as those offered by the financial sphere through the use of conditional cash transfers, socialexpenditures and subsidies, tax collection products, others Government revenues and indebtedness. Although in Latin American countries poverty can be temporarily reduce through these government instruments, economic inequality will be maintained or will continue to increase, as will the opportunity grabbing, until there is no structural changes, primarily in the tax field, along with many other integrated solutions beyond the object of our study.

Pautas críticas de la relación existente entre los programas de TMC y los impuestos regresivos al consumo en Argentina

Pautas críticas de la relación existente entre los programas de TMC y los impuestos regresivos al consumo en Argentina Rezzoagli, Luciano Carlos; Villalba, Andres; Perini, Agustina A pesar de la implementación de diversos Programas de TMC y la consecuente, aunque discutida por su escaso nivel de evaluación y control reducción de los índices de pobreza e indigencia y aumento efectivo de inserción laboral de sectores poblacionales vulnerables, Argentina continúa conservando altos niveles de desigualdad. Desde una vertiente de análisis financista, esta situación se debe --en gran medida-- a la consolidación de un sistema detractivo altamente regresivo, caracterizado por la imposición de tributos indirectos predominantes que gravan actividades productivas, intermedias y productos finales de consumo sin tener en cuenta la capacidad contributiva efectiva de los destinatarios reales o incidentales del tributo. En un país como Argentina, perteneciente al continente más desigual del mundo, es indispensable empezar a ser, y no parecer: la estructuración del sistema fiscal debe perseguir y alentar la consecución de una clase media estructural, tomando como punto de partida un contexto de agudas asimetrías económicas tanto a nivel poblacional como a nivel geográfico regional. Una de las principales falencias que consolidan estas situaciones que sufren innumerables familias es la falta de articulación de reformas fiscales que tiendan al desarrollo y consolidación de una clase media estructural mediante un sistema impositivo progresivo, inclusivo y responsable.

El programa de liberación nacional en la Argentina de los 70: La convergencia entre Montoneros y la Confederación General Económica (CGE)

El programa de liberación nacional en la Argentina de los 70: La convergencia entre Montoneros y la Confederación General Económica (CGE); The program of national liberation in the 70s Argentina: from Montoneros to the Confederación General Económica (CGE) Sanz Cerbino, Gonzalo Sebastian; Lissandrello, Guido Axel En este artículo realizamos un estudio del programa político de dos importantes actores del proceso político de la década del ’70 en Argentina: la organización político-militar Montoneros y la corporación empresaria Confederación General Económica (CGE). Mediante el análisis comparado de los documentos fundamentales de ambos, buscamos detectar aspectos comunes y elementos distintivos entre uno y otro. Concluimos que desarrollan variantes de un mismo programa que se plantea el fin del dominio imperialista y la defensa de los intereses nacionales, mediante el estímulo a la empresa nacional y la redistribución del ingreso: el programa de liberación nacional.; In this article we conducted a study of the political program of two major players in the political process in the 70s in Argentina: the military-political organization Montoneros and the interest group Confederación General Económica (CGE). Through a comparative analysis of the fundamental documents of both organizations, we seek to detect coincidences and distinctive elements of each other. We conclude that they develop variants of the same program which propose the end of imperialist domination and defense of national interests, by encouraging national company and income redistribution: the program of national liberation.

Los industriales automotores y la crisis de la década de 1980 en Argentina

Los industriales automotores y la crisis de la década de 1980 en Argentina; Automotive entrepreneurs and the crisis of the 1980s in Argentina Bil, Damián Andrés Analizamos aquí los elementos de la crisis automotriz iniciada en 1978, las condiciones del mercado y la situación de las terminales en la década de 1980. Luego, nos concentramos en el estudio de las posiciones de los empresarios, tanto en términos individuales como actuando en forma colectiva frente a la recesión. Con esto, buscamos aportar al conocimiento sobre las dificultades de la industria argentina en los 80 y sobre la historia de la burguesía local en este período. Utilizamos informes oficiales y privados, series oficiales, publicaciones periódicas y aportes de otros autores.; We analyze the elements of the automotive crisis initiated in 1978, and the market conditions and te situation of the terminals in the 1980s. Then, we focus on the study of the positions of businessmen, both individually and collectively at the time of economic recession. We seek to contribute to the knowledge about the difficulties of the Argentine industry in the ‘80s and the history of the local bourgeoisie in this period. We use official and private reports, journals of the period and contributions from other authors.

A comparative study of the gastric ossicles of Trichodactylidae crabs (Brachyura: Decapoda) with comments on the role of diet and phylogeny in shaping morphological traits

A comparative study of the gastric ossicles of Trichodactylidae crabs (Brachyura: Decapoda) with comments on the role of diet and phylogeny in shaping morphological traits de Azevedo Carvalho, Débora; Collins, Pablo Agustin; Lima Gomes, Renata; Magalhaes Filho, Celio Ubirajara; Torres, María Victoria; Williner, Verónica The gastric armature of decapod foregut is a feeding structure that sparks controversial debates about the role dietary and historical components have in shaping its morphological traits. Having previous information about the natural diet is an interesting way to gather evidence on this issue. For the present study, we analyzed the morphological traits of gastric ossicles involved directly in the maceration of food in nine species of freshwater crabs of the family Trichodactylidae (Brachyura: Decapoda) representing five genera, three tribes and two subfamilies. The analyzed gastric ossicles were quite consistent among closely related species, suggesting that the observed traits had a clear phylogenetic component. However, it was also noted that the morphological traits of the gastric teeth of trichodactylid crabs match well with the natural diet and presented likeness with general features of other species with a similar trophic habit. We discuss the influence of phylogeny and function on the design of morphological traits and propose to quantify the role of phylogeny and function in shaping morphological traits through the analysis of phylogenetic signals.

Development of 3D printed fibrillar collagen scaffold for tissue engineering

Development of 3D printed fibrillar collagen scaffold for tissue engineering Díaz Nocera, Aden; Comin, Romina; Salvatierra, Nancy Alicia; Cid, Mariana Paula Collagen is widely used in tissue engineering because it can be extracted in large quantities, and has excellent biocompatibility, good biodegradability, and weak antigenicity. In the present study, we isolated printable collagen from bovine Achilles tendon and examined the purity of the isolated collagen using sodium dodecyl sulfate polyacrylamide gel electrophoresis. The bands obtained corresponded to α 1 , α 2 and β chains with little contamination from other small proteins. Furthermore, rheological measurements of collagen dispersions (60 mg per ml of PBS) at pH 7 revealed values of viscosity of 35.62 ± 1.42 Pa s at shear rate of 10 s − 1 and a shear thinning behavior. Collagen gels and solutions can be used for building scaffolds by three-dimensional (3D) printing. After designing and fabricating a low-cost 3D printer we assayed the collagen printing and obtaining 3D printed scaffolds of collagen at pH 7. The porosity of the scaffold was 90.22% ± 0.88% and the swelling ratio was 1437% ± 146%. The microstructure of the scaffolds was studied using scanning electron microscopy, and a porous mesh of fibrillar collagen was observed. In addition, the 3D printed collagen scaffold was not cytotoxic with cell viability higher than 70% using Vero and NIH 3 T3 cells. In vitro evaluation using both cells lines demonstrated that the collagen scaffolds had the ability to support cell attachment and proliferation. Also a fibrillar collagen mesh was observed after two weeks of culture at 37 °C. Overall, these results are promising since they show the capability of the presented protocol to obtain printable fibrillar collagen at pH 7 and the potential of the printing technique for building low-cost biocompatible 3D plotted structures which maintained the fibrillar collagen structure after incubation in culture media without using additional strategies as crosslinking.

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

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)

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

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

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

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

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

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

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

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

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.

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