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Gd0.2Ca0.8MnO3 thin films were deposited on various substrate materials and their structural and resistive switching (RS) properties were investigated. The deposition resulted in epitaxial and polycrystalline films, with the latter also exhibiting distorted film surfaces. Both epitaxial and a part of polycrystalline films used as RS devices showed consistent RS performance in which an order of magnitude, or higher, switching ratios were achieved between high and low resistance states. The devices showed strong endurance during repeated switching cycles. However, under retention characterization, the resistance states did not remain distinguishable in devices constructed on polycrystalline films, while other devices maintained separable resistance states. The RS results are discussed in relation to the structural characteristics of the films, and this work helps us understand the RS mechanisms that still remain elusive in manganite-based devices.

Abstract Background An effective biomaterial for bone replacement should have properties to avoid bacterial contamination and promote bone formation while inducing rapid cell differentiation simultaneously. Bone marrow stem cells are currently being investigated because of their known potential for differentiation in osteoblast lineage. This makes these cells a good option for stem cell-based therapy. We have aimed to analyze, in vitro, the potential of pure titanium (Ti), Ti-35Nb-7Zr alloy (A), niobium (Nb), and zirconia (Zr) to avoid the microorganisms S. aureus (S.a) and P. aeruginosa (P.a). Furthermore, our objective was to evaluate if the basic elements of Ti-35Nb-7Zr alloy have any influence on bone marrow stromal cells, the source of stem cells, and observe if these metals have properties to induce cell differentiation into osteoblasts. Methods Bone marrow stromal cells (BMSC) were obtained from mice femurs and cultured in osteogenic media without dexamethasone as an external source of cell differentiation. The samples were divided into Ti-35Nb-7Zr alloy (A), pure titanium (Ti), Nb (niobium), and Zr (zirconia) and were characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). After predetermined periods, cell interaction, cytotoxicity, proliferation, and cell differentiation tests were performed. For monotypic biofilm formation, standardized suspensions (106 cells/ml) with the microorganisms S. aureus (S.a) and P. aeruginosa (P.a) were cultured for 24 h on the samples and submitted to an MTT test. Results All samples presented cell proliferation, growth, and spreading. All groups presented cell viability above 70%, but the alloy (A) showed better results, with statistical differences from Nb and Zr samples. Zr expressed higher ALP activity and was statistically different from the other groups (p < 0.05). In contrast, no statistical difference was observed between the samples as regards mineralization nodules. Lower biofilm formation of S.a and P.a. was observed on the Nb samples, with statistical differences from the other samples. Conclusion Our results suggest that the basic elements present in the alloy have osteoinductive characteristics, and Zr has a good influence on bone marrow stromal cell differentiation. We also believe that Nb has the best potential for reducing the formation of microbial biofilms.

A figure refuses to conform and bow down to anyone, both in the ancient Greek literature that first portrayed it and at present, in our attempts to constrain it in order to define it: they are the γόης, the ‘sorcerer’, the ‘enchanter’ that dominates Athens in the V-IV centuries BC. Who were they? And what role did they play in the power struggle in the πόλις par excellence? In literary sources we find that the γόητες were engaged in many dangerous endeavours: their abilities ranged from appeasing the restless shadows of the dead, to instigating them against the living. However, their incredible powers were not limited to the Underworld, since, through their voices, they could easily bend the very will of the living. Commonly pictured as outsiders (e.g. in Euripides’ Bacchae and Hippolytus), foreigners, at the beginning they were liminal figures in Athens, called upon in the exceptional circumstances in which their deadly skills were required. My paper will show what happened when the γόητες entered the city of Athens to stay. The balance has been toppled; the outsiders stand at the very core of the πόλις and play with its rulers. Through Plato’s dialogues (Euthydemus, Gorgias, Laws, Protagoras, Republic, Sophist), I will show the extent of the powers of these ‘law-breakers’, the ways in which they seeped into every aspect of the life of the city. In the end, who is the true ruler of Athens?

Superheroes exist in multiple narratives and storyworlds at the same time. Some of the stories and iterations are part of the character's canon, while different adaptations and alternative versions inhabit other timelines and fictional worlds. Using the concept of transmedia universe, this article explores how fan-made and corporate-made adaptations of the character of Batman occupied the same universe and expanded the world inhabited by the character. Approaching the historical phenomenon of the 1960s Batmania from the point of view of adaptation studies, the article sheds light on local adaptations in a transmedia context. [ABSTRACT FROM AUTHOR]

Harnessing the full power of memristors as artificial synapses demands a simple and scalable crossbar architecture enabling their seamless integration into diverse applications. This Letter presents the 3 × 3 memristor crossbar array configuration featuring a grid of interconnected devices. The composition includes Al as the reactive top electrode connecting the device columns and Gd1−xCaxMnO3 (GCMO, x = 0.8) serving as the bottom electrode connecting the device rows as well as the memristive material eliminating the need for additional layers and fabrication steps. Controlled-sized vias through insulating the Al2O3 layer connect the electrodes forming the active interface. The idea is validated with a test sample of 3 × 3 crossbars with the Au/GCMO/Al structure, Au enabling Ohmic contact to GCMO, with device resistive switching ratios mostly around 102 and yield of over 90%. The devised crossbar structure could provide a highly scalable, yet simple, geometry suitable for synaptic networks. [ABSTRACT FROM AUTHOR]

Cell-cell interactions are crucial for organ development and function. In the heart, endothelial cells engage in bidirectional communication with cardiomyocytes regulating cardiac development and growth. We aimed to elucidate the organotypic development of cardiac endothelial cells and cardiomyocyte and endothelial cell crosstalk using human induced pluripotent stem cells (hiPSC). Single-cell RNA sequencing was performed with hiPSC-derived cardiomyocytes (hiPS-CMs) and endothelial cells (hiPS-ECs) in mono- and co-culture. The presence of hiPS-CMs led to increased expression of transcripts related to vascular development and maturation, cardiac development, as well as cardiac endothelial cell and endocardium-specific genes in hiPS-ECs. Interestingly, co-culture induced the expression of cardiomyocyte myofibrillar genes and MYL7 and MYL4 protein expression was detected in hiPS-ECs. Major regulators of BMP- and Notch-signaling pathways were induced in both cell types in co-culture. These results reflect the findings from animal studies and extend them to human endothelial cells, demonstrating the importance of EC-CM interactions during development.

The vascular system is essential for the development and function of all organs and tissues in our body. The molecular signature and phenotype of endothelial cells (EC) are greatly affected by blood flow-induced shear stress, which is a vital component of vascular development and homeostasis. Recent advances in differentiation of ECs from human induced pluripotent stem cells (hiPSC) have enabled development of in vitro experimental models of the vasculature containing cells from healthy individuals or from patients harboring genetic variants or diseases of interest. Here we have used hiPSC-derived ECs and bulk- and single-cell RNA sequencing to study the effect of flow on the transcriptomic landscape of hiPSC-ECs and their heterogeneity. We demonstrate that hiPS-ECs are plastic and they adapt to flow by expressing known flow-induced genes. Single-cell RNA sequencing showed that flow induced a more homogenous and homeostatically more stable EC population compared to static cultures, as genes related to cell polarization, barrier formation and glucose and fatty acid transport were induced. The hiPS-ECs increased both arterial and venous markers when exposed to flow. Interestingly, while in general there was a greater increase in the venous markers, one cluster with more arterial-like hiPS-ECs was detected. Single-cell RNA sequencing revealed that not all hiPS-ECs are similar even after sorting, but exposing them to flow increases their homogeneity. Since hiPS-ECs resemble immature ECs and demonstrate high plasticity in response to flow, they provide an excellent model to study vascular development.

Existe desde el 2010 un marco normativo en Uruguay que dispone la equiparación de oportunidades para las personas con discapacidad. Sin embargo, las imposiciones legales no modifican la práctica docente en al aula. Este trabajo tiene el objetivo de conocer las actitudes de los docentes con la finalidad de entender su predisposición para actuar y realizar una propuesta de intervención en aula que atienda la diversidad. La población estudiada está formada por 42 docentes de educación primaria de centros educativos públicos, ubicados en localidades rurales y urbanas de Uruguay. Se aplicó la Escala de Actitudes hacia las Personas con Discapacidad (Verdugo, Arias & Jenaro, 1992). Se encontró una relación estadísticamente significativa entre la formación inicial de los maestros respecto a la actitud general, la implicación personal y el reconocimiento/negación de derechos.

La convergencia de la integral que da el tiempo propio en función del tiempo inercial, cuando la velocidad tiende a la velocidad de la luz lo suficientemente rápido mientras el tiempo inercial tiende al infinito, fue estudiada en 1985. Aquí se reconsidera este problema en el marco de la teoría restringida de la relatividad. Nada especial (además de la tasa de crecimiento hacia el infinito) parece caracterizar el comportamiento de la componente tangencial de los campos de 3-fuerza a lo largo de la trayectoria del reloj acelerado, en relación con la convergencia o divergencia de la integral que da el tiempo propio como función del tiempo inercial. Sin embargo, visto desde el punto de vista de la aceleración propia del reloj, aparece una diferencia físicamente significativa entre los dos casos lógicamente posibles. Uno está integrado por las historias de 3-aceleración propia tangenciales que dan un tiempo propio finito para un tiempo inercial infinito. El otro está integrado por las historias de 3-aceleraciones propias tangenciales que dan un tiempo propio infinito para un tiempo inercial infinito. En el primer caso aparece una singularidad en la 3-aceleracion propia para un valor finito de tiempo propio. En el segundo caso esa singularidad no aparece. Los resultados obtenidos se comparan, en el marco de la teoría de la relatividad general, con el la rela-ción entre el tiempo propio y el tiempo inercial durante la caída de una partícula hacia un agujero negro. Se enfatizan las consecuencias de estos resultados sobre la validez de un postulado que se encuentra en la base de la formulación original de la teoría de la relatividad, según el cual todos los observadores en el universo, con independencia de su estado de movimiento, deben estar de acuerdo sobre la ocurrencia de ciertos sucesos, tales como explosiones e implosiones, nacimientos y muertes.

Se construye un modelo matemático para estudiar el crecimiento difuso axial y radial de la pared primaria de células vegetales. Se obtienen fórmulas analíticas para el cociente de anisotro- pía del crecimiento de Erickson y para los parámetros de la ecuación aumentada de Ortega, en función de los parámetros del nuevo modelo. Se introduce una relación constitutiva no lineal en el modelo de Lockhart y se consideran algunos aspectos del modelo de crecimiento axial generalizado.

Gd0.2Ca0.8MnO3 thin films were deposited on various substrate materials and their structural and resistive switching (RS) properties were investigated. The deposition resulted in epitaxial and polycrystalline films, with the latter also exhibiting distorted film surfaces. Both epitaxial and a part of polycrystalline films used as RS devices showed consistent RS performance in which an order of magnitude, or higher, switching ratios were achieved between high and low resistance states. The devices showed strong endurance during repeated switching cycles. However, under retention characterization, the resistance states did not remain distinguishable in devices constructed on polycrystalline films, while other devices maintained separable resistance states. The RS results are discussed in relation to the structural characteristics of the films, and this work helps us understand the RS mechanisms that still remain elusive in manganite-based devices. [ABSTRACT FROM AUTHOR]

Se analizan algunos problemas que se plantean en relación con la modalidad contemporánea de capitalismo (denominado capitalismo desigual por Jean-Yves Calvez) desde una perspectiva sociohistórica y filosófica. Se discuten posibles soluciones, fundamentalmente desde la perspectiva del capitalismo natural, enfatizando los aspectos morales y políticos.