Directional solidification of dilute Sn-Pb alloys

Microstructure evolution and pattern formation during directional solidification of dilute Sn-Pb system were analysed. Planar, cellular and dendritic morphologies were obtained by adequate thermal gradient and interface velocity control. The samples were obtained from pure elements in concentrations of 0·05, 1·0 and 4·0 wt-%Pb. Growth was carried out in a Bridgman device in the velocity range of 0·38-30 μm s -1 at thermal gradients from 1·3 to 2·6°C mm -1. The samples were examined using metallographic techniques to determine their morphology and dimensional characteristics. The system was analysed to describe the different stages of evolution of the morphology and transitions. It was observed that both primary cellular and dendritic spacing decreased with increasing velocity. However, in the cellular-dendritic transition zone, an important increase in spacing was detected and basically associated with convective effects during irregular cellular growth.Fil: Ochoa, H.. Universidad de Antofagasta (uantof);Fil: Fornaro, Osvaldo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Física de Materiales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; ArgentinaFil: Bustos, O.. Universidad de Santiago de Chile; ChileFil: Schulz, B.. Universidad de Santiago de Chile; Chil

Jednostavna i ekonomična metoda detekcije saksitoksina praćenjem promjene struktura aptamera

A simple method to detect saxitoxin (STX), one of the main components of the paralytic shellfish poison from red tide, has been developed. By using a next generation dye for double-stranded DNA we were able to differentiate fluorescence from STX-binding aptamers when exposed to different concentrations of STX, suggesting a change in aptamer folding upon target binding. The developed method is extremely rapid, only requiring small sample volumes, with quantitative results in the concentration range of 15 ng/mL to 3 μg/mL of STX, with a detection limit of 7.5 ng/mL.Razvijena je jednostavna metoda detekcije saksitoksina, jednog od glavnih sastojaka paralitičkog toksina školjkaša prisutnih u moru preplavljenom dinoflagelatima (tzv. crvena plima). Upotrebom najnovije generacije fluorescentne boje za dvolančanu DNA bilo je moguće razlikovati fluorescenciju aptamera specifičnog za saksitoksin pri različitim koncentracijama, zbog čega smo pretpostavili da se struktura aptamera promijenila nakon vezanja na saksitoksin. Razvijena metoda je jako brza, za određivanje je potreban mali volumen uzorka, te se prisutnost saksitoksina može odrediti u rasponu koncentracija od 15 ng/mL do 3 µg/mL, s donjom granicom detekcije od 7,5 ng/mL

New evidence about the subduction of the Copiap\uf2 ridge beneath South America, and its connection with the Chilean-Pampean flat slab, tracked by satellite GOCE and EGM2008 models

Satellite-only gravity measurements and those integrated with terrestrial observations provide global gravity field models of unprecedented precision and spatial resolution, which allow analyzing lithospheric structure allowing the analysis of the lithospheric structure. We used the model EGM2008 (Earth Gravitational Model) to calculate the gravity anomaly and the vertical gravity gradient in the South Central Andes region, correcting these quantities by the topographic effect. Both quantities show a spatial relationship between the projected subduction of the Copiap\uf3 aseismic ridge (located at 33 about 27\uba 30\u2019 S), its potential deformational effects in the overriding plate, and the Ojos del Salado-San Buenaventura volcanic lineament. This volcanic lineament constitutes a projection of the volcanic arc towards the retroarc zone, whose origin and development were not clearly understood. The analysis of the gravity anomalies, at the extrapolated zone of the Copiap\uf3 ridge beneath the continent, shows a change in the general NNE38 trend of the Andean structures to an ENE-direction coincident with the area of the Ojos del Salado-San Buenaventura volcanic lineament. This anomalous pattern over the upper plate is interpreted to be linked with the subduction of the Copiap\uf3 ridge. We explore the relation between deformational effects and volcanism at the northern Chilean-Pampean flat slab and the collision of the Copiap\uf3 ridge, on the basis of the Moho geometry and elastic thicknesses calculated from the new satellite GOCE data. Neotectonic deformations interpreted in previous works associated with volcanic eruptions along the Ojos del Salado-San Buenaventura volcanic lineament is interpreted as caused by crustal doming, imprinted by the subduction of the Copiap\uf3 ridge, evidenced by crustal thickening at the sites of ridge inception along the trench. Finally, we propose that the Copiap\uf3 ridge could have controlled the northern edge of the Chilean-Pampean flat slab, due to higher buoyancy, similarly to the control that the Juan Fernandez ridge exerts in the geometry of the flat slab further south

Sexual Dimorphism and Estrogen Regulation of KCNE3 Expression Modulates the Functional Properties of KCNQ1 K+ Channels

The KCNQ1 potassium channel associates with various KCNE ancillary subunits that drastically affect channel gating and pharmacology. Co-assembly with KCNE3 produces a current with nearly instantaneous activation, some time-dependent activation at very positive potentials, a linear current voltage relationship and a 10-fold higher sensitivity to chromanol 293B. KCNQ1:KCNE3 channels are expressed in colonic crypts and mediate basolateral K+ recycling required for Cl- secretion. We have previously reported the female-specific anti-secretory effects of estrogen via KCNQ1:KCNE3 channel inhibition in colonic crypts. This study was designed to determine whether gender and estrogen regulate the expression and function of KCNQ1 and KCNE3 in rat distal colon. Colonic crypts were isolated from Sprague-Dawley rats and used for whole-cell patch-clamp and to extract total RNA and protein. Sheets of epithelium were used for short-circuit current recordings. KCNE1 and KCNE3 mRNA and protein abundance was significantly higher in male than female crypts. No expression of KCNE2 was found and no difference was observed in KCNQ1 expression between male and female (at estrous) colonic crypts. Male crypts showed a 2.2-fold higher level of association of KCNQ1 and KCNE3 compared to female cells. In female colonic crypts, KCNQ1 and KCNE3 protein expression fluctuated throughout the estrous cycle and 17-estradiol (E2 10 nM) produced a rapid (\u3c15\u3emin) dissociation of KCNQ1 and KCNE3 in female crypts only. Whole-cell K+ currents showed a linear current-voltage relationship in male crypts, while K+ currents in colonic crypts isolated from females displayed voltage-dependent outward rectification. Currents in isolated male crypts and epithelial sheets were 10-fold more sensitive to specific KCNQ1 inhibitors, such as chromanol 293B and HMR-1556, than in female. The effect of E2 on K+ currents mediated by KCNQ1 with or without different -subunits was assayed from current-voltage relations elicited in CHO cells transfected with KCNQ1 and KCNE3 or KCNE1 cDNA. E2 (100 nM) reduced the currents mediated by the KCNQ1:KCNE3 potassium channel and had no effect on currents via KCNQ1:KCNE1 or KCNQ1 alone. Currents mediated by the complex formed by KCNQ1 and the mutant KCNE3-S82A β-subunit showed rapid run-down and insensitivity to E2. Together, these data suggest that estrogen regulates the expression of the KCNE1 and KCNE3 and with it the gating and pharmacological properties of the K+ conductance required for Cl- secretion. The decreased association of the KCNQ1:KCNE3 channel complex promoted by estrogen exposure underlies the molecular mechanism for the sexual dimorphism and estrous cycle dependence of the anti-secretory actions of estrogen in the intestine

Parque cultural como espacio multigeneracional para su integración con el entorno urbano – Huaraz 2023

La presente tesis titulada “PARQUE CULTURAL COMO ESPACIO MULTIGENERACIONAL PARA SU INTEGRACIÓN CON EL ENTORNO URBANO – HUARAZ 2023” definiéndolo como al lugar donde todas las personas pueden acceder y participar de las actividades y de los bienes culturales en su calidad de público y/o creadores, asimismo dicho espacio funciona como motor que anima al encuentro, la convivencia y el reconocimiento cultural de una comunidad en sus distintas actividades, entre muchos otros. teniendo como teoría de la arquitectura paisajística, teoría del patrimonio cultural, teoría del espacio público y derecho a la ciudad, teoría del espacio multigeneracional. teniendo como objetivo diseñar una infraestructura donde se realizan actividades recreativos socio culturales, incentivará el crecimiento cultural y de las relaciones sociales recreativas, de intercambio y demostración cultural, ínter institucional con entidades locales, regionales, nacionales e internacionales ampliando así las proyecciones de desarrollo para mejorar la calidad de vida. luego se analizaron tres proyecto de tesis como casos análogos para saber cómo abordar el proyecto, seguidamente se hizo la propuesta arquitectónica enmarcada en la normatividad nacional y finalmente se realizó el análisis de las características del lugar lo cual permitió determinar la composición formal y funcional del proyecto Por otro lado, haciendo referencia al tipo de investigación, fue de enfoque cualitativo, de carácter descriptivo y de diseño no experimental, transversal, los instrumentos que se utilizaron fueron la ficha de registro documental, la ficha de observación y la guía de entrevista, en donde en la guía de entrevista se plantearon preguntas relacionadas al tema. El proyecto busca responder a temáticas sociales por lo que al implementarse un parque cultural se aprovecharía los recursos naturales y arqueológicos otorgándoles un valor agregado que activarían la economía de la ciudad y por ende mejoraría la calidad de vida de la población

Rehabilitaci?n de la estaci?n del ferrocarril de Girardot Cundinamarca : Una propuesta de conservaci?n de la memoria colectiva y consolidaci?n urbana

301 p. Recurso Electr?nicoLa formulaci?n de la propuesta de revitalizaci?n de la estaci?n del ferrocarril de Girardot, Cundinamarca, se dio a trav?s de un cambio de uso y dise?o de obra anexa de estaci?n de ferrocarril, tomando como pauta el plan especial de manejo y protecci?n (pEMP) del corredor f?rreo Girardot ? Facatativ? elaborado por la sociedad cundinamarquesa de ingenieros y actualmente radicado en el ministerio de cultura. Los lineamientos de conservaci?n, consolidaci?n e intervenci?n proporcionados por el PEMP del corredor f?rreo Girardot ?Facatativ?, donde se abarca el corredor f?rreo y obras de arquitectura e ingenier?a que los componen se toman como pauta y elementos generadores de dise?o que garanticen la preservaci?n de la memoria colectiva; lo cual, acompa?ado de un proceso de b?squeda de informaci?n a trav?s de encuestas y entrevistas con habitantes del municipio, profesionales conocedores del tema y pensionados del ferrocarril, permiti? un enfoque social, de tejido urbano de las nuevas obras y el cambio de uso de la estaci?n del ferrocarril, donde el espacio p?blico adquiere un car?cter articulador urbano y social que fortalezcan el factor tur?stico de la regi?n. La rehabilitaci?n del sector tiene como elemento articulador de dise?o urbano la conectividad entre la estaci?n de ferrocarril y el embarcadero tur?stico a trav?s de un malec?n en el borde de ciudad sobre el r?o magdalena, recuperando de esta forma un eje de turismo importante para la regi?n. Palabras clave: memoria colectiva, estaci?n de ferrocarril, plan especial de manejo y protecci?n, turismo regional.The proposed revitalization of the railway station Girardot, Cundinamarca, through a change of use to tourism center layout and design of adjacent railroad station work, is given taking as a guideline the special management plan and protection (MEWP ) of the railway corridor Girardot - Cundinamarca Facatativ? prepared by the society of engineers and currently based in the ministry of culture. Conservation guidelines, consolidation and intervention provided by the MEWP Girardot -Facatativ? the railway corridor, where the railway corridor and works of architecture and engineering that covers up is taken as pattern generators and design elements that ensure the preservation of memory collective; which, accompanied by a process of finding information through surveys and interviews with residents of the municipality and retired railroad Girardot, he allowed a social and urban fabric of the new works approach and changing use of the railway station where the public space takes on an articulator urban and social factor strengthen tourism in the region. Rehabilitation sector is linchpin of urban design connectivity between the railway station and the tourist pier through a levee on the edge of town on the Magdalena River, recovering this way an axis of important regional tourism. Keywords: collective memory, railway station, special management and protection plan, regional touris

Relationship between mature software engineering practices and agility practices

This paper reports on research work on Argentinean software development organizations. The analysis pro-vides insights on the profile of the companies regarding the usage of agile methods and software engineering practices trends, their motivations, and drivers. The conclusions can be used to understand what drivers facilitate the understanding of bonds between both in order to increase their competitiveness in domestic and off-shore markets.Sociedad Argentina de Informática e Investigación Operativ

Agile and software engineering, an invisible bond

The bond between agile practices and Software Engineering practices is clear and apparent for sea-soned practitioners with experience on the operation of high maturity development environments, yet it’s often ig-nored on the domain bibliography where most hybrid approaches are adopted. This article reviews a sensible sam-ple of the bibliography to confirm that trend and develop a map between what long established Software Engineer-ing practices and concepts stated as agile foundation principles. Previous research efforts are integrated into rein-forcing which aspects of an agile-based project need to be addressed with priority to protect the additional value yield by the usage of these methodologies.Sociedad Argentina de Informática e Investigación Operativ