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High stability of properties in morphotropic phase boundary Bi0.5Na0.5TiO3–BaTiO3 piezoceramics

High stability of properties in morphotropic phase boundary Bi0.5Na0.5TiO3–BaTiO3 piezoceramics Machado, Rodrigo; Ochoa, Diego; dos Santos, Valdeci B.; Cerdeiras, Elena; Mestres, Lourdes; García, José E. The (1−x)Bi0.5Na0.5TiO3–xBaTiO3 (BNT-xBT) system with composition at its morphotropic phase boundary (MPB) has received significant attention because of their attractive properties as lead-free piezoceramics. Although the basic properties of this system are well-established, reports about the stability of the functional properties of these piezoelectric materials are still lacking. A study on the dielectric and piezoelectric properties of BNT-xBT close to their MPB, with emphasis on material response under high electric field or mechanical stress, is performed in this work. The results indicate that the BNT-BT system exhibits a high stability of dielectric and piezoelectric properties, making it potentially interesting for specific applications. A direct correlation between piezoelectric properties and nonlinear response is evidenced for a wide number of piezoceramics, which is expected due to the extrinsic nature of the piezoelectric response. Finding compositions that show high electromechanical properties and low nonlinear behavior is a challenge in the search for competitive lead-free piezoceramics.

Prevalence and infection intensity of Rickettsia massiliae in Rhipicephalus sanguineus sensu lato ticks from Mendoza, Argentina

Prevalence and infection intensity of Rickettsia massiliae in Rhipicephalus sanguineus sensu lato ticks from Mendoza, Argentina Monje, Lucas Daniel; Linares, Maria Cielo; Beldomenico, Pablo Martín Rickettsia massiliae belongs to the spotted fever group and in the New World is commonly associated with the brown dog tick, Rhipicephalus sanguineus. Herein we investigate the presence of R. massiliae in Rh. sanguineus sensu lato ticks in a location near the Andean foothills (Mendoza, Argentina), to provide a prevalence estimate and to assess the infection intensity of this pathogen. Rickettsia massiliae infection was found in 5.1% of the Rh. sanguineus s.l ticks analyzed, all with high infection intensities. Molecular analysis determined that all R. massiliae-infected Rh. sanguineus s.l. ticks belonged to the temperate lineage.

Comprehensive study of growth mechanism and properties of low Zn content Cd1-xZnxS thin films by chemical bath

Comprehensive study of growth mechanism and properties of low Zn content Cd1-xZnxS thin films by chemical bath Rodríguez, Carlos Aníbal; Sandoval Paz, Myrna Guadalupe; Saavedra, Renato; Trejo Cruz, Cuauhtémoc; De la Carrera, Francisco; Aragón, Luis Enrique; Sirena, Martin; Delplancke, Marie Paule; Carrasco, Claudia Cd1-xZnxS thin films have been studied extensively as window layers for solar cell applications. However, a mismatch between the Cd1-xZnxS and copper-indium-gallium-selenide absorber layers increases with Zn film concentration, which reduces the device eficiency. In this work, Cd1-xZnxS thin films with low Zn concentrations were analyzed. The effect of the addition of different molar Zn concentrations to the reaction mixture on the growth mechanism of Cd1-xZnxS thin films and the influence of these mechanisms on structural, optical and morphological properties of the films has been studied. Cd1-xZnxS thin films were synthesized by chemical bath deposition using an ammonia-free alkaline solution. Microstructural analysis by X-ray diffraction showed that all deposited films grew with hexagonal structure and crystallite sizes decreased as the Zn concentration in the film increased. Optical measurements indicated a high optical transmission between 75% and 90% for wavelengths above the absorption edge. Band gap value increased from 2.48 eV to 2.62 eV, and the refractive index values for Cd1-xZnxS thin films decreased as the Zn increased. These changes in films and properties are related to a modification in growth mechanism of the Cd1-xZnxS thin films, with the influence of Zn(OH)2 formation being more important as Zn in solution increases.

Hindered cytoplasmic diffusion of inositol trisphosphate restricts its cellular range of action

Hindered cytoplasmic diffusion of inositol trisphosphate restricts its cellular range of action Dickinson, George D.; Ellefsen, Kyle L.; Ponce Dawson, Silvina Martha; Pearson, John E.; Parker, Ian The range of action of intracellular messengers is determined by their rates of diffusion and degradation. Previous measurements in oocyte cytoplasmic extracts indicated that the Ca2+-liberating secondmessenger inositol trisphosphate (IP3) diffuses with a coefficient (∼280 mm2 s-1) similar to that in water, corresponding to a range of action of ∼25 mm. Consequently, IP3 is generally considered a "global" cellular messenger. We reexamined this issue by measuring local IP3-evoked Ca2+ puffs to monitor IP3 diffusing from spot photorelease in neuroblastoma cells. Fitting these data by numerical simulations yielded a diffusion coefficient (≤10 mm2 s-1) about 30-fold slower than that previously reported. We propose that diffusion of IP3 in mammalian cells is hindered by binding to immobile, functionally inactive receptors that were diluted in oocyte extracts. The predicted range of action of IP3 (<5 mm) is thus smaller than the size of typical mammalian cells, indicating that IP3 should better be considered as a local rather than a global cellular messenger. 2016

Cellular basis of pineal gland development: Emerging role of microglia as phenotype regulator

Cellular basis of pineal gland development: Emerging role of microglia as phenotype regulator Ibañez Rodriguez, María Paula; Noctor, Stephen C.; Muñoz, Estela Maris The adult pineal gland is composed of pinealocytes, astrocytes, microglia, and other interstitial cells that have been described in detail. However, factors that contribute to pineal development have not been fully elucidated, nor have pineal cell lineages been well characterized. We applied systematic double, triple and quadruple labeling of cell-specific markers on prenatal, postnatal and mature rat pineal gland tissue combined with confocal microscopy to provide a comprehensive view of the cellular dynamics and cell lineages that contribute to pineal gland development. The pineal gland begins as an evagination of neuroepithelium in the roof of the third ventricle. The pineal primordium initially consists of radially aligned Pax6+ precursor cells that express vimentin and divide at the ventricular lumen. After the tubular neuroepithelium fuses, the distribution of Pax6+ cells transitions to include rosette-like structures and later, dispersed cells. In the developing gland all dividing cells express Pax6, indicating that Pax6+ precursor cells generate pinealocytes and some interstitial cells. The density of Pax6+ cells decreases across pineal development as a result of cellular differentiation and microglial phagocytosis, but Pax6+ cells remain in the adult gland as a distinct population. Microglial colonization begins after pineal recess formation. Microglial phagocytosis of Pax6+ cells is not common at early stages but increases as microglia colonize the gland. In the postnatal gland microglia affiliate with Tuj1+ nerve fibers, IB4+ blood vessels, and Pax6+ cells. We demonstrate that microglia engulf Pax6+ cells, nerve fibers, and blood vessel-related elements, but not pinealocytes. We conclude that microglia play a role in pineal gland formation and homeostasis by regulating the precursor cell population, remodeling blood vessels and pruning sympathetic nerve fibers.

About a center in a liénard type system and qualitative properties associated

About a center in a liénard type system and qualitative properties associated Napoles Valdes, Juan Eduardo; Guzmán, Paulo Matias; Lugo Motta Bittencourt, Luciano Miguel In this paper, we study the existence of local o global center of Liénard type system (1), under non -usual assumptions.The boundedness and the oscillatory nature of solutions of that system are also obtained.

A transient fault-valve mechanism operating in upper crustal level, Sierras Pampeanas, Argentina

A transient fault-valve mechanism operating in upper crustal level, Sierras Pampeanas, Argentina Japas, Maria Silvia; Urbina, Nilda Esther; Sruoga, Patricia; Garro, José Matías; Ibañes, Oscar Damián Located in the Sierras Pampeanas (the broken-foreland of the Pampean flat slab segment in the southern Central Andes), the Cerro Tiporco volcanic field shows Neogene hydrothermal activity linked to migration of arc-magmatism into the foreland. Late Neogene deposits comprise epithermal vein systems emplaced in Precambrian—Early Palaeozoic igneous-metamorphic basement, Late Miocene sedimentary rocks and Early Pliocene volcaniclastic rocks. Mineralization consists of calcareous onyx, aragonite and calcite veins as well as travertine deposits. Onyx and aragonite occur as fill of low-displacement nearly vertical reverse-sinistral faults striking NW, and nearly horizontal dilatant fractures. The latter consist of load-removal induced fractures affecting the igneous-metamorphic rocks, as well as bedding planes in the Late Miocene sediments. The presence of veins recording multiple fracture episodes and crack-and-seal growth of veins suggests relatively low differential stress and supralithostatic fluid pressure, as well as cyclic changes in pore pressure and high mineral-deposition/fracture-opening ratio. These conditions support a mechanism of fault-valve behaviour during onyx and aragonite vein emplacement. The fault-valve mechanism involves fractures associated with impermeable barriers between environments with different fluid pressure. Faulting generated an appreciable directional permeability triggering fluid migration from the highest to the lowest pressure region, with subsequent deposition and sealing that started a new pressurization-faulting-sealing cycle. Late aragonite and calcite veins suggest a change in kinematics indicating the onset of tectonic-load conditions.

The Quaternary record of Euneomys (Mammalia, Rodentia, Cricetidae) from northwestern Patagonia: evidence for regional extinction

The Quaternary record of Euneomys (Mammalia, Rodentia, Cricetidae) from northwestern Patagonia: evidence for regional extinction Tammone, Mauro Nicolás; Lacey, Eileen Anne; Hajduk, Adan; Christie, Miguel; Pardiñas, Ulises Francisco J. SUPPLEMENTAL DATA: Supplemental materials are available for this article for free at www.tandfonline.com/UJVP

Lo local y lo nacional en los estudios del peronismo: aportes desde la Patagonia

Lo local y lo nacional en los estudios del peronismo: aportes desde la Patagonia Carrizo, Gabriel Alejandro El artículo refiere a la presentación de un dossier dedicado a los estudios sobre el peronismo en la Patagonia. Dicho dossier recoge algunas producciones presentadas en el Congreso sobre Lo local y lo Nacional en los Estudios del Peronismo, realizadas en la ciudad de Esquel en abril del 2015.

Gestionar la reciprocidad: Trabajo docente y vínculos intergeneracionales en la escuela secundaria

Gestionar la reciprocidad: Trabajo docente y vínculos intergeneracionales en la escuela secundaria García Bastán, Guido En nuestras aproximaciones al contexto escolar observamos que, para los educadores, la regulación de la relación con sus estudiantes constituye uno de los aprendizajes más costosos de la construcción de su rol, que parecería producirse con un importante margen de autonomía. En Argentina, investigaciones actuales permiten situar estas experiencias docentes en una configuración socio-histórica caracterizada, a partir de los años sesenta, por transformaciones en los vínculos de generación que habrían dado lugar a un escenario que carece de consensos y modelos claros respecto de cómo estos vínculos deberían establecerse. Partiendo de esta proposición, exploraremos algunas prácticas regulativas docentes en la especificidad de un orden de interacción escolar, en el que las tensiones entre lógicas igualitarias y jerárquicas imprimen a la tarea docente el desafío de gestionar la reciprocidad. El análisis de los soportes de estas prácticas regulativas nos permitirá considerar algunos modos en que ciertas disposiciones básicas del trabajo docente en Argentina condicionan las modalidades de vinculación intergeneracional. Lo que conlleva reflexiones acerca de las condiciones en que se desarrolla esta tarea.; During our approaches to secondary schools, we have observed that educators consider the regulation of their relation with pupils as one of the most difficult learnings that seem to develop quite autonomously. In Argentina, current researches allow to locate these experiences at a social historical configuration characterized, from the ‘60s onwards, by changes in intergenerational relations, leading to a scenario with a lack of clear models on how these relations should be held. From this proposition, we´ll explore some teacher ways of regulation, considering the specificity of the school interactional order, in which tensions between equity and hierarchy demands challenges educators to manage reciprocity. The analysis of the supports to these regulation practices will allow us to give account for some of the ways in which certain basic dispositions of the teaching labor in Argentina condition the ways of inter-generational linkage. This implies reflections over working conditions.

Introducción: Historia de la Asistencia en Brasil y Argentina: saberes, experiencias y prácticas

Introducción: Historia de la Asistencia en Brasil y Argentina: saberes, experiencias y prácticas; History of public and private welfare in Brazil and Argentina: knowledge, experience and practices Gonçalves Alves, Ismael; de Paz Trueba, Yolanda Edith; Rabelo,Giani; Bracamonte, Lucia Esta edición tiene por objetivo presentar y poner en discusión diversas aristas de la historia de la asistencia en Brasil y en Argentina, a partir de las contribuciones de investigadores e investigadoras que se dedican a esta temática. En los últimos veinte años, en ambos países, se produjo una cantidad significativa de análisis históricos que problematizan las respuestas estatales, filantrópicas y asociacionistas a las nuevas exigencias de la sociedad urbano-industrial.; This special edition of DeRLAS consists of ten articles in Spanish and Portuguese on the history of public and private welfare programs in Brazil and Argentina. The articles present and bring into discussion various points of intersection in the contributions of researchers dedicated to the subject. In both countries, over the last twenty years, the significant quantity of historical analysis that has been produced raises questions about the response of state, philanthropic and community organizations to the new demands of industrial urban society.

Structural and functional characterization of a cold adapted TPM-domain with ATPase/ADPase activity

Structural and functional characterization of a cold adapted TPM-domain with ATPase/ADPase activity Cerutti, Maria Laura; Otero, Lisandro Horacio; Smal, Clara; Pellizza, Leonardo; Goldbaum, Fernando Alberto; Klinke, Sebastian; Aran, Martin The Pfam PF04536 TPM_phosphatase family is a broadly conserved family of domains found across prokaryotes, plants and invertebrates. Despite having a similar protein fold, members of this family have been implicated in diverse cellular processes and found in varied subcellular localizations. Very recently, the biochemical characterization of two evolutionary divergent TPM domains has shown that they are able to hydrolyze phosphate groups from different substrates. However, there are still incorrect functional annotations and uncertain relationships between the structure and function of this family of domains. BA41 is an uncharacterized single-pass transmembrane protein from the Antarctic psychrotolerant bacterium Bizionia argentinensis with a predicted compact extracytoplasmic TPM domain and a C-terminal cytoplasmic low complexity region. To shed light on the structural properties that enable TPM domains to adopt divergent roles, we here accomplish a comprehensive structural and functional characterization of the central TPM domain of BA41 (BA41-TPM). Contrary to its predicted function as a beta-propeller methanol dehydrogenase, light scattering and crystallographic studies showed that BA41-TPM behaves as a globular monomeric protein and adopts a conserved Rossmann fold, typically observed in other TPM domain structures. Although the crystal structure reveals the conservation of residues involved in substrate binding, no putative catalytic or intramolecular metal ions were detected. Most important, however, extensive biochemical studies demonstrated that BA41-TPM has hydrolase activity against ADP, ATP, and other di- and triphosphate nucleotides and shares properties of cold-adapted enzymes. The role of BA41 in extracellular ATP-mediated signaling pathways and its occurrence in environmental and pathogenic microorganisms is discussed.

The anthraquinones rubiadin and its 1-methyl ether isolated from Heterophyllaea pustulata reduces Candida tropicalis bioÞlms formation

The anthraquinones rubiadin and its 1-methyl ether isolated from Heterophyllaea pustulata reduces Candida tropicalis bioÞlms formation Marioni, Juliana; Da Silva, María Angel; Cabrera, Jose Luis; Núñez Montoya, Susana Carolina; Paraje, María Gabriela Background: Candida tropicalis is increasingly becoming among the most commonly isolated pathogens causing fungal infections with an important biofilm-forming capacity.Purpose: This study addresses the antifungal effect of rubiadin (AQ1) and rubiadin 1-methyl ether (AQ2), two photosensitizing anthraquinones (AQs) isolated from Heterophyllaea pustulata, against C. tropicalis biofilms, by studying the cellular stress and antioxidant response in two experimental conditions: darkness and irradiation. The combination with Amphotericin B (AmB) was assayed to evaluate the synergic effect.Study Design/Methods: Biofilms of clinical isolates and reference strain of Candida tropicalis were treated with AQs (AQ1 or AQ2) and/or AmB, and the biofilms depletion was studied by crystal violet and confocal scanning laser microscopy (CSLM). The oxidant metabolites production and the response of antioxidant defense system were also evaluated under dark and irradiation conditions, being the light a trigger for photo-activation of the AQs. The Reactive Oxygen Species (ROS) were detected by the reduction of Nitro Blue Tetrazolium test, and Reactive Nitrogen Intermediates (RNI) by the Griess assay. ROS accumulation was also detected inside biofilms by using 2′,7′-Dichlorodihydrofluorescein diacetate (DCFH-DA) probe, which was visualized by CSLM. Superoxide dismutase (SOD) activity and the total antioxidant capacity of biofilms were measured by spectrophotometric methods. The minimun inhibitory concentration for sessile cells (SMIC) was determined for each AQs and AmB. The fractional inhibitory concentration index (FICI) was calculated for thecombinations of each AQ with AmB by the checkerboard microdilution method.Results: Biofilm reduction of both strains was more effective with AQ1 than with AQ2. The antifungal effect was mediated by an oxidative and nitrosative stress under irradiation, with a significant accumulation of endogenous ROS detected by CSLM and an increase in the SOD activity. Thus, the prooxidant-antioxidant balance was altered especially by AQ1. The best synergic combination with AmB was also obtained with AQ1 (80.5 %) (FICI = 0.74).Conclusion: Under irradiation, the oxidative stress was the predominant effect, altering the prooxidant-antioxidant balance, which may be the cause of the irreversible cell injury in the biofilm. Our results showed synergism of these natural AQs with AmB. Therefore, the photosensitizing AQ1 could be an alternative for the Candida infections treatment, which deserves further investigation.

Immune mediators associated to male infertility in a mouse model of DNA immunization with the sperm protease proacrosin

Immune mediators associated to male infertility in a mouse model of DNA immunization with the sperm protease proacrosin Russi, Romina; Garcia, Maria Ines; Vignatti, Paulina; Veiga, Maria Florencia; Vazquez, Monica Hebe; Veaute, Carolina Melania Isabel The immune response has relevant physiological functions both in the male and female reproductive system, and must be tightly controlled to achieve a successful pregnancy. Several immune factors have been related to infertility, among them humoral and cellular immune responses triggered by sperm antigens. The present study was aimed at evaluating the immune profile induced by DNA immunization against the sperm protease proacrosin in CF1 male mice and its effect upon fertility. Immunized animals exhibited higher anti-proacrosin antibodies levels than controls (indirect ELISA), both in serum (p<0.01) and in seminal vesicle fluid (SVF; p<0.05). IgG2a levels were higher than IgG1 in serum (p<0.01) and similar in SVF. IL-10 and TGF-β1 mRNA levels were lower in testis (p<0.05), whereas TNF-α and IFN-γ transcript levels were increased in SV tissue (p<0.05). Immunized mice showed a trend toward higher IFN-γ concentration in serum and SVF than controls. Male fertility rate was diminished in immunized mice (p<0.01) and inversely correlated with serum and SVF anti-proacrosin IgG levels (p<0.001). Immunized animals also had fewer pups born than controls (p<0.01). To our knowledge, this is the first report on DNA immunization done in CF1 mice. Injection of proacrosin DNA induces an immune response in the male reproductive tract characterized by high levels of specific antibodies and cytokine changes. These factors may alter the crucial balance of the genital tract microenvironment required for adequate fertilization and pregnancy.

Stomach nematodes of three sympatric species of anatid birds off the coast of Patagonia

Stomach nematodes of three sympatric species of anatid birds off the coast of Patagonia Agüero, M. L.; Gilardoni, Carmen Mariangel; Cremonte, Florencia; Diaz, Julia Inés The present study focuses on the nematode community in the stomachs of three sympatric anatid bird species from the Central Patagonian coast, Argentina. The bird species include the Chubut steamer duck, Tachyeres leucocephalus, the crested duck, Lophonetta specularioides, and the black-necked swan, Cygnus melancoryphus. Up to 138 nematodes representing five species were recovered from 10 of the 13 ducks examined, with an overall prevalence of 77% and a mean intensity of 13.8. Nematodes isolated from the gizzard were Streptocara formosensis and Sciadiocara legendrei (Acuariidae) in T. leucocephalus, and Epomidiostomum vogelsangi (Amidostomatidae) in C. melancoryphus, whereas Echinuria uncinata (Acuariidae) and Tetrameres (Petrowimeres) fissispina (Tetrameriidae) were found in the proventiculus of L. specularioides. In particular, S. legendrei was registered for the first time in South America and T. leucocephalus, whereas T. fissispina represents a new record in Argentina and L. specularioides. Moreover, E. vogelsangi and E. uncinata were isolated in Patagonia for the first time. The birds studied herein are sympatric in their distribution, and two of them are syntopic breeders; however, they were infected with different parasite species. This situation could be partially due to their diet or their seasonal movements, or a combination of both. Despite the low number of hosts examined, this work enhances our knowledge about parasites from a frequently occurring group of birds on the Patagonian coast, a subject that has not been studied extensively in South America.

Criticality of environmental information obtainable by dynamically controlled quantum probes

Criticality of environmental information obtainable by dynamically controlled quantum probes Zwick, Analía Elizabeth; Alvarez, Gonzalo Agustin; Kurizki, Gershon A universal approach to decoherence control combined with quantum estimation theory reveals a critical behavior, akin to a phase transition, of the information obtainable by a qubit probe concerning the memory time of environmental fluctuations of generalized Ornstein-Uhlenbeck processes. The criticality is intrinsic to the environmental fluctuations but emerges only when the probe is subject to suitable dynamical control aimed at inferring the memory time. A sharp transition is anticipated between two dynamical phases characterized by either a short or long memory time compared to the probing time. This phase transition of the environmental information is a fundamental feature that characterizes open quantum-system dynamics and is important for attaining the highest estimation precision of the environment memory time under experimental limitations.

Physical and mechanical properties of raspberries subjected to osmotic dehydration and further dehydration by air- and freeze-drying

Physical and mechanical properties of raspberries subjected to osmotic dehydration and further dehydration by air- and freeze-drying Sette, Paula Andrea; Salvatori, Daniela Marisol; Schebor, Carolina Claudia The aim of this study was to analyze the effect of the application of dry and wet sucrose infusions, as pretreatments previous to air- and freeze-drying, on mechanical and physical properties of raspberries: water sorption, glass transition temperature (Tg), molecular mobility, texture and rehydration properties. Different dry and wet sugar infusions were prepared using combinations of additives: sodium bisulphite, citric acid, sodium bisulphite and citric acid, and no additives. These specific pretreatments are often used to obtain better sensorial characteristics of fruits upon further drying. After the dehydration step (air- or freeze-drying), all the samples were in the supercooled state. Pretreated samples presented lower Tg values and lower spin–spin relaxation times than control samples. Regarding texture, pretreated samples showed lower firmness than control samples. Also, freeze-dried pretreated samples showed higher firmness and lower deformability than air-dried pretreated ones. When considering the hygroscopicity, freeze-dried samples were more hygroscopic than air-dried ones. The fresh-like dried raspberries obtained could be directly consumed as snacks or incorporated in a composite food, such as a cereal mix. In this latter case, pretreated fruits would be more suitable, since their rehydration capacity at short times was relatively low.

Gallbladder cancer: South American experience

Gallbladder cancer: South American experience Arroyo, Gerardo F.; Gentile, Alberto; Parada, Luis Antonio Large differences in terms of incidence and mortality due to gallbladder cancer (GBC) have been reported worldwide. Moreover, it seems that GBC has unique characteristics in South America. We surveyed the literature looking for information about the epidemiology, basic and translational research, and clinical trials performed in South America in order to critically analyze the magnitude of this health problem in the region. Compared to other geographic areas, age-standardized mortality rates (ASMR) for GBC in women are very high, particularly in many western areas of South America. Genetic, as well as dietary and environmental factors likely contribute to the pathogenesis of this disease in the area. Compared to other regions the profile of abnormalities of key genes such as KRAS and TP53 in GBC seems to slightly differ in South America, while the clinical behavior appears to be similar with a median overall survival (OS) of 6.5 to 8 months in advanced GBC. In contrast to Europe and USA, prophylactic cholecystectomy is a common practice in western areas of South America. GBC particularly affects women in South America, and represents a significant public health problem. It appears to have peculiarities that pose an urgent need for additional research aimed to discover risk factors, molecular events associated with its development and new treatment options for this lethal disease.

Una técnica robusta para modelar el rompimiento de la estela vorticosa en generadores eólicos de gran potencia y eje horizontal

Una técnica robusta para modelar el rompimiento de la estela vorticosa en generadores eólicos de gran potencia y eje horizontal Gomez, Cynthia Noelia; Preidikman, Sergio; Lopez Mejia, Omar D.; Roccia, Bruno Antonio Con el fin de aumentar el conocimiento del comportamiento aerodinámico de turbinas eólicas de eje horizontal y de gran potencia y lograr así un correcto diseño de las mismas, los estudios aerodinámicos, aeroelásticos y aeroservoelásticos de estos sistemas de generación de energías limpias han recobrado interés durante los últimos años. En este trabajo se presenta el desarrollo e implementación computacional de un nuevo método de simulación del fenómeno de ruptura de las estelas vorticosas generadas por las palas al impactar la torre portante; dicha componente influye de manera directa en el comportamiento de la potencia mecánica de la turbina. La nueva técnica numérica se implementó en un código computacional ya existente, basado en una versión modificada del método de red de vórtices no lineal y no estacionario. Con el objetivo de poner en evidencia la eficiencia y robustez del nuevo método de ruptura, se comparan los resultados numéricos con un esquema desarrollado con anterioridad. Además, se analiza cualitativamente la forma de la ruptura al variar el número de elementos aerodinámicos utilizados para discretizar las palas y la torre. Finalmente, para analizar cuantitativamente la influencia de la discretización aerodinámica de la pala en el modelo de ruptura, se calculan los tiempos dimensionales de comienzo y finalización de la primera ruptura de estela y se extraen conclusiones.; With the objective of increasing knowledge regarding the behavior of Large-Scale Horizontal-Axis Wind Turbines (LSHAWTs) and provide a correct design for them, during the last years, the aerodynamic, aeroelastic and aeroservoelastic studies have become of interest. In this paper, a new numerical method to simulate the wake rupture against the supporting tower is developed. This simulation scheme is implemented into an existing computational code and represents an improvement in the process of detecting wake vortex segments going through the body of the tower. The numerical tool is based on a modified version of the well-known unsteady vortex-lattice method. In order to validate the efficiency and robustness of the proposed wake rupture method, current numerical results are compared against results obtained using a numerical scheme developed previously. Moreover, a qualitative analysis of shape variations of the wake rupture as a function of the number of aerodynamic elements on both the blades and the tower is carried out. Finally, to analyze quantitatively the influence of aerodynamic discretization of the blade on the wake rupture model, the starting- and ending-time of the first rupture are computed. Conclusions are drawn.

Genomic imbalances and microRNA transcriptional profiles in patients with mycosis fungoides

Genomic imbalances and microRNA transcriptional profiles in patients with mycosis fungoides Garaicoa, Fuad Huaman; Roisman, Alejandro; Arias, Mariana; Trila, Carla; Fridmanis, Miguel; Abeldaño, Alejandra; Vanzulli, Silvia; Narbaitz, Marina; Slavutsky, Irma Rosa Mycosis fungoides is the most common type of primary cutaneous T cell lymphoma. We have evaluated CDKN2A losses and MYC gains/amplifications by FISH analysis, as well as expression of miR-155 and members of the oncogenic cluster miR-17-92 (miR17, miR18a, miR19b, and miR92a) in MF patients with advanced disease. Formalin-fixed paraffin-embedded skin biopsies from 36 patients at diagnosis, 16 with tumoral MF (T-MF), 13 in histological transformation to a large T cell lymphoma (TR-MF), and 7 cases with folliculotropic variant (F-MF), were studied. Twenty cases showed genomic alterations (GAs): 8 (40 %) had CDKN2A deletion, 7 (35 %) showed MYC gain, and 5 (25 %) exhibited both alterations. GAs were more frequently observed in F-MF (p = 0.004) and TR-MF (p = 0.0001) than T-MF. GAs were significantly higher in cases presenting lesions in head, neck, and lower extremities compared to those observed in trunk and upper extremities (p = 0.03), when ≥25 % neoplastic cells were CD30 positive (p = 0.016) as well as in cases with higher Ki-67 proliferation index (p = 0.003). Patients with GAs showed bad response to treatment (p = 0.02) and short survival (p = 0.04). Furthermore, MF patients showed higher miRNA expression compared to controls (p ≤ 0.0223). T-MF showed higher miR17 and miR-18a expression compared to F-MF and TR-MF (p ≤ 0.0387) while miR19b, miR92a, and miR-155 showed increased levels in F-MF and TR-MF with respect to T-MF (p ≤ 0.0360). Increased expression of miR17 and miR19b in GA group compared to cases without alterations (p ≥ 0.0307) was also detected. Our results add new information about genomic imbalances in MF patients, particularly in F-MF, and extend the present view of miRNA deregulation in this disease.

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