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In our study, we show that compositional engineering of the “A” site cation of ABX3 perovskite structure formed by a mix of organic and inorganic cations is an effective route to improve the thermal stability of perovskite solar cells (PSCs). In this work, mixed-cation mixed-halide PSCs have been fabricated and characterized with temperature, from 253 up to 333 K. The active layer based on CsRbFAMAPb(IBr)3 results in a more stable device compared to standard MAPbI3 devices. Electrical characterization reveals a decrease of the solar cell parameters with temperature. Using Impedance Spectroscopy (IS) characterization, we have estimated an activation energy for the halide ion migration of 0.63 ± 0.08 eV, an ion diffusion coefficient of 10−14 cm2 s−1, and a defect density of 7.27·1015 cm−3. To our knowledge, this is the first time that these parameters have been calculated in CsRbFAMAPb(IBr)3 based devices, resulting in improved values compared to MAPbI3 devices. The worsening of device performance for temperatures above 300 K is attributed to a decrease of the spiro-OMeTAD conductivity and the degradation of the perovskite/spiro-OMeTAD interface. It is shown that for low temperatures (from 253 to 323 K), Shockley-Red-Hall (SRH) recombination in the bulk governs, while for temperatures above 323 K the increase in surface recombination becomes dominant due to the presence of non-selective contacts. Numerical simulations using SILVACO ATLAS corroborate the role of SRH in the perovskite active layer for low and medium temperatures, and the crucial influence of spiro-OMeTAD transport properties in the device performance parameters.

Chile’s war against the Peruvian-Bolivian Confederation was a conflict that developed between these countries during the years 1836 and 1839. Analyzed mainly from the military and political point of view, the studies that has been carried out so far has not given greater attention to the role that the press for the consolidation of the Chilean victory. The review of the National Archive of Peru and the newspapers of the time highlight the importance that the Chilean and Peruvian authorities attributed to the press in validating the intervention with the population. Along with this, in this article analyzes and recreates the information dynamics of the time, the campaign against the Confederation and Andres Santa Cruz and the economic difficulties of the new Peruvian government in keeping the population informed., La guerra de Chile contra la Confederación Perú-Boliviana fue un conflicto que se desarrolló entre estos países durante los años 1836 y 1839. Analizado mayoritariamente desde el punto de vista militar y político, los estudios que se han realizado hasta ahora no han prestado mayor atención al rol que tuvo la prensa para la consolidación de la victoria chilena. La revisión del Archivo Nacional de Perú y de los periódicos de la época dejan en evidencia la importancia que las autoridades chilenas y peruanas atribuyeron a la prensa para validar la intervención frente a la población. Junto con esto, en el presente artículo se analizan y recrean las dinámicas informativas de la época, la propaganda contra la Confederación y el general Andrés Santa Cruz y las dificultades económicas del nuevo gobierno peruano para mantener informada a la población

This article reviews, through primary sources, the life of General Bernardo O'Higgins during exile in Peru, the problems he faced in this country and, furthermore, the unknown role he had in the Chilean war against the Peru-Bolivian Confederation. This research reviews and compares the route that O'Higgins traveled with the Englishman John Thomas in 1823 and the road that the Restoration Army used in his second expedition, under the command of General Manuel Bulnes in 1838. The advice of the hero of independence was key in Bulnes's decision to leave the Peruvian capital with his force and concentrate in the north to confront and defeat the army of the Peru-Bolivian Confederation., El presente artículo revisa, a través de fuentes primarias, la vida del general Bernardo O'Higgins durante el destierro en Perú, los problemas que enfrentó en este país y, además, el desconocido rol que tuvo en la guerra de Chile contra la Confederación Perú-boliviana. La presente investigación repasa y compara la ruta que recorrió O´Higgins junto al inglés John Thomas en 1823 y la senda que utilizó el Ejército Restaurador en su segunda expedición, al mando del general Manuel Bulnes en 1838. El consejo del héroe de la independencia fue clave en la decisión de Bulnes de abandonar con su fuerza la capital peruana y concentrarse en el norte para enfrentar y derrotar al ejército de la Confederación Perú-boliviana.

The crisis between Argentina and Chile during the year 1978 has been the subject of several investigations on both sides of the mountain range. The proposal of this study is to analyze the conflict through the Chilean cartoonists who published in the main media of national circulation. In general terms, the review of the cartoons, in contrast to the press reports, makes it clear that it was through the cartoons that the media expressed its most critical position on Argentine politics. The moderation of the editorials, press releases and reports contrasts with the aggressiveness of the Chilean cartoonists in response to the constant aggression of the argentine military dictatorship, their diplomacy and the Andean press., La crisis entre Argentina y Chile durante el año 1978 ha sido objeto de diversas investigaciones en los dos lados de la cordillera. La propuesta de este estudio es analizar el conflicto a través de los caricaturistas chilenos que publicaron en los principales medios de circulación nacional. En términos generales, la revisión de las viñetas, en contraste con las informaciones de prensa, deja en evidencia que fue por intermedio de las caricaturas que los medios manifestaron su postura más crítica respecto a la política argentina. La mesura de las editoriales, notas de prensa y reportajes contrasta con la agresividad que manifestaron los caricaturistas chilenos como respuesta a las constantes agresiones de la dictadura militar argentina, su diplomacia y la prensa trasandina.

El presente artículo tiene como objetivo analizar la postura del general Bernardo O´Higgins durante la guerra de Chile contra la Confederación Perú-Boliviana. La revisión de su epistolario, mientras estuvo en Perú, dejaría en evidencia que sus intereses económicos fueron claves al momento de tener que determinar el apoyo a uno u otro bando. Más allá de la mirada idealizada en contra del conflicto, que sus defensores han buscado destacar, se esconde un hombre pragmático, preocupado de resguardar sus intereses particulares., The objective of this article is to analyze the position of General Bernardo O'Higgins during the Chilean War against the Peru-Bolivian Confederation. The review of their correspondence, while he was in Peru, would leave in evidence that economic interests were the key at the time of having to determine support for one side or the other. Beyond the idealized look against the conflict, which its defenders have sought to highlight, hides a pragmatic man, anxious to protect their interests.

The aim of this article is to analyze the relevance of the wheat and general trade as determinant factors in the war that Chile waged against the Peru-Bolivian Confederation. This research is based on the files at the National Historic Archives in Chile as well as the local press and private correspondence. The comparative study of those sources allows us to understand the very close relation among the commercial competition between Chile and Peru, the wheat crisis in Chile, and the declaration of war against the Confederation. Also, the fact that the same people organized the second Chilean expeditionary force and the founding of the National Agricultural Society by the very same people shows that both dynamics formed part of the same political and economics project., El objetivo de este artículo es analizar la relevancia del comercio del trigo como uno de los factores determinantes en la guerra de Chile contra la Confederación Perú-Boliviana. A partir de oficios del Archivo Histórico Nacional de Chile, cartas y prensa del periodo, el estudio comparado de las fuentes permite evidenciar la estrecha relación entre la tensión comercial entre Perú y Chile, la crisis del trigo en Chile y la declaración de guerra de este país a la Confederación. Asimismo, la organización de la segunda expedición chilena y la fundación de la Sociedad Nacional de Agricultura, por los mismos protagonistas, induce a especular que ambos acontecimientos formaban parte de un mismo proyecto político y económico.

Segmentation is a crucial stage in hand biometric recognition due to its direct influence on the feature extractionprocess. The actual trend toward contactless biometrics adds new challenges to traditional defiances, which are mainly relatedto the capturing conditions and the limitations on computational resources. Traditional methods do not succeed when variablecapturing conditions are imposed and methods which are able to deal with daily-life situations are, in general, computationallyexpensive. In this study, a competitive flooding-based segmentation method oriented to mobile devices is proposed in order toachieve a compromised solution between accuracy and computational resources consumption. The method has been evaluatedusing images coming from five different databases which cover a wide spectrum of capturing conditions, one of them recordedas a part of this study. The results have been compared with other two well known segmentation techniques in terms of bothaccuracy and computation time.

This article aims to analyze the stay of the Bolivian GeneralAndres de Santa Cruz in Chile, after the defeat of the ConfederateArmy in the fields of Yungay. From the review of thepress, letters, and official documents of the time, the traditionalimage of Santa Cruz as a threat to the interests of Chilecontrasts with the care granted by President Bulnes during hisstay in this country. The study of the biography of Santa Cruzand the relationship with his peers, at this stage of his life, canapproach the construction of the Latin American states from adifferent perspective. The concern of the Chilean governmentby the Bolivian explain the close relationship between theleaders of this period, trade links and the transition from onegeneration before and after independence., Este artículo tiene como propósito analizar la estadía del generalboliviano Andrés de Santa Cruz en Chile, luego de laderrota de su ejército confederado en los campos de Yungay.A partir de la revisión de la prensa, cartas, oficios y memoriasde la época, la imagen tradicional de Santa Cruz como unaamenaza a los intereses de Chile contrasta con los cuidadosconcedidos por el Presidente Bulnes durante su permanenciaen este país. El estudio de la biografía de Santa Cruz y dela relación con sus pares, en esta etapa de su vida, permiteaproximarnos a la construcción de los estados latinoamericanosdesde una óptica distinta. La preocupación del Gobiernochileno por el boliviano explicaría la estrecha relación entrelos líderes de esta época, nexos comerciales y la transición deuna generación antes y después de la independencia.