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Pyrazole derivatives are key in crystal engineering and liquid crystal fields and thrive in agriculture, pharmaceutical, or biomedicine industries. Such versatility relies in their supramolecular bond adaptability when forming hydrogen bonds or metal-pyrazole complexes. Interestingly, the precise structure of pyrazole-based macrocycles forming widespread porous structures is still unsolved. We bring insight into such fundamental question by studying the self-assembled structures of a bis-pyrazole derivative sublimed in ultra-high-vacuum conditions (without solvents) onto the three (111) noble metal surfaces. By means of high-resolution scanning tunneling microscopy that is validated by gas phase density functional theory calculations, we find a common hexagonal nanoporous network condensed by triple hydrogen bonds at the molecule-metal interface. Such assembly is disrupted and divergent after annealing: (i) on copper, the molecular integrity is compromised leading to structural chaos, (ii) on silver, an incommensurate new oblique structure requiring molecular deprotonation is found and, (iii) on gold, metal-organic complexes are promoted yielding irregular chain structures. Our findings confirm the critical role of these metals on the different pyrazole nanoporous structure formation, discarding their preference for metal incorporation into the connecting nodes whenever there is no solvent involved.

Pyrazole derivatives are key in crystal engineering and liquid crystal fields and thrive in agriculture, pharmaceutical, or biomedicine industries. Such versatility relies in their supramolecular bond adaptability when forming hydrogen bonds or metal-pyrazole complexes. Interestingly, the precise structure of pyrazole-based macrocycles forming widespread porous structures is still unsolved. We bring insight into such fundamental question by studying the self-assembled structures of a bis-pyrazole derivative sublimed in ultra-high-vacuum conditions (without solvents) onto the three (111) noble metal surfaces. By means of high-resolution scanning tunneling microscopy that is validated by gas phase density functional theory calculations, we find a common hexagonal nanoporous network condensed by triple hydrogen bonds at the molecule–metal interface. Such assembly is disrupted and divergent after annealing: (i) on copper, the molecular integrity is compromised leading to structural chaos, (ii) on silver, an incommensurate new oblique structure requiring molecular deprotonation is found and, (iii) on gold, metal–organic complexes are promoted yielding irregular chain structures. Our findings confirm the critical role of these metals on the different pyrazole nanoporous structure formation, discarding their preference for metal incorporation into the connecting nodes whenever there is no solvent involved.

In the following text, we explore the concept of boredom in light of the current model of enter- tainment. From a critical perspective, we are convinced that what the Frankfurt School referred to as the culture industry has evolved in such a way that today it is capable of providing us with what we will call technified entertainment. This is a form of entertainment made possible by the advancement of technology and provided by the cultural industry, with all that it entails. Our attitude towards this model of entertainment should be one of suspicion, and thus, we will approach Heidegger ́s analysis of boredom in his 1929 course. We will examine what existential possibilities boredom can offer and whether or not the prohibition of boredom should be rejected. The stance we aim to defend is that when we experience boredom, we find ourselves in a privileged situation to ponder fundamental questions. Therefore, if we eliminate boredom from our lives, these essential questions would be jeopardized., En el siguiente texto tratamos de pensar en el aburrimiento a partir del modelo actual de entretenimiento. Desde una perspectiva crítica, estamos convencidos de que lo que los filósofos de la escuela de Frankfurt llamaron «industria cultural» ha evolucionado de tal forma que hoy es capaz de suministrarnos lo que llamaremos «entretenimiento tecnificado». Este se trata de una forma de entretenimiento que es posibilitado por el avance de la técnica y proporcionado por la industria cultural, con todo lo que ello supone. La actitud que debemos mantener frente al suministro de este modelo de entretenimiento debe ser de sospecha y por ello realizaremos una aproximación al análisis que Heidegger hace del aburrimiento en su curso de 1929. Nos aproximaremos a este texto para examinar qué posibilidades existenciales nos puede brindar el aburrimiento y si la prohibición de este debe ser o no rechazada. La postura que tratamos de defender es que al estar aburridos nos encontramos en una situación privilegiada para preguntar por cuestiones fundamentales y, por tanto, si expulsamos de nuestras vidas el aburrimiento, estas preguntas serían puestas en peligro.

Out patient Surgery has reached a very important degree of development in our country, becoming widespread in multiple procedures in recent years, representing more than 85% of the activity of a Department of Surgery and with a offer of services that continues to expand, but this expansion it has not been as widely accepted in the case of thyroid and parathyroid surgery. At the same time, the "thyroidectomy" process has undergone an important transformation with the appearance of new technologies that have provided safety and quality to the procedure, so its inclusion in out patient surgery modality should be generalized., La Cirugía Mayor Ambulatoria ha alcanzado un grado de desarrollo muy importante en nuestro país, generalizándose en múltiples procedimientos en los últimos años, representando mas del 85% de la actividad de un servicio de cirugía y con una cartera de servicios que sigue ampliándose pero esta expansión no ha sido tan ampliamente aceptada en el caso de la cirugía tiroidea y paratiroidea. Al mismo tiempo, el proceso "tiroidectomía" ha sufrido una importante transformación con la aparición de nuevas tecnologías que han aportado seguridad y calidad al procedimiento por lo que su inclusión en régimen de Cirugía mayor Ambulatoria debería poderse generalizar.

El hemangioma cavernoso suprarrenal es un tumor benigno extremadamente raro. Hasta la fecha, solo hay aproximadamente 70 casos descritos en la literatura. En la mayoría de los casos es hormonalmente silencioso. No suele provocar síntomas, por lo que suele diagnosticarse como hallazgo incidental tras realizar pruebas de imagen por otro motivo., Adrenal cavernous hemangioma is an extremely rare benign tumor. To date, there are only approximately 70 cases described in the literature. In most cases it is hormonally silent. It does not usually cause symptoms, so it is usually diagnosed as an incidental finding after performing imaging tests for another reason.

Este estudio analizó las características de los movimientos comunitarios que han cobrado fuerza tras el inicio de la crisis económica en estos últimos años. El trabajo de campo se realizó en cuatro contextos específicos de experiencias comunitarias: Dos de Monedas Sociales, uno de Huertos Urbanos, y otro de Bancos del Tiempo. Hipótesis: Los movimientos de base comunitaria que suponen una ayuda a aspectos económicos de las familias e individuos, toman fuerza en situaciones de crisis económicas, en el contexto de la globalización económica. Metodología: Se hicieron 82 encuestas del Cuestionario ECOM, compuesto de 48 preguntas, y que abarca el análisis de 77 variables. El estudio aportó la conexión entre la situación de crisis y desempleo con la participación en estas actividades; la vinculación de la edad a la participación en contextos distintos; el origen universitario y en desempleo de los participantes; consideración de estas iniciativas comunitarias como una forma de mercado o economía alternativa; vinculación con el principio de bien común; la participación basada en la confianza; y la desconexión entre lo global y lo local dentro de estas iniciativas., This study analyzed the characteristics of community movements which have grown along the economic crisis in recent years. The research was conducted in four specific contexts of community experiences: Two in Social Money, one in Urban Gardens, and the last one in Time’s Banks. Hypothesis: community-based movements involving aid economic aspects of families and individuals are becoming stronger in times of economic crisis, in the economic globalization context. Methodology: 82 surveys trough the ECOM Questionnaire, composed of 48 questions and 77 variables. The study provided us the connection between the crisis and unemployment; linking participant's age with the different contexts; unemployed university in the origin to participation; consideration of these community initiatives as a way of market or as an alternative economy; linkage with the principle of commons; participation based on trust; and the disconnection between the global and the local within these initiatives., Escuela de Estudios Cooperativos, Fac. de Ciencias Económicas y Empresariales, TRUE, pub

We have synthesized two geometric isomers of a cyclohexane-5-spirohydantoin derivative (1,3-diazaspiro[4.5]decane-2,4-dione) incorporating a hydrophobic phenyl 3,4,5-tris(dodecyloxy)benzoate unit at position 8. Separation of these diastereomers was accomplished through silica gel flash chromatography. The interplay of intermolecular hydrogen bonding and micro-segregation between the polar hydantoin unit and nonpolar aliphatic chains within the molecule endows them with remarkable self-assembly capabilities, both in solution and in the solid state. These hydantoin derivatives spontaneously form rosette-shaped structures composed of six molecules. In the solid state, these compounds display hexagonal columnar liquid crystal phases, with hydrogen-bonded disks as their fundamental building blocks. Similarly, when exposed to apolar solvents such as cyclohexane or dodecane, they adopt a columnar arrangement, resulting in gel formation comprising nanoscale fibers that intricately interlace to form a network. Remarkably, the two isomers exhibit markedly different properties. The major isomer behaves as a glassy liquid crystalline material, while the minor one exhibits liquid crystalline behavior with a high propensity to crystallize. Our experimental findings, in combination with theoretical studies, underscore the fundamentally distinct supramolecular organizations present in these isomers, shedding light on their unique self-assembling properties.

We have developed a new strategy for the preparation of a light-responsive ionic liquid crystal (LC) that shows photo-switchable proton conduction. The ionic LC consists of a bowl-shaped calix[4]arene core ionically functionalized with azobenzene moieties. The non-covalent architectures were obtained by the formation of ionic salts between the carboxylic acid group of an azo-derivative and the terminal amine groups of a calixarene core. The presence of ionic salts results in a hierarchical self-assembly process that extends to the formation of a nanostructured lamellar LC arrangement (smectic A phase). In this LC phase, the ionic LC calixarene is able to display proton conductive properties, since the ionic nanosegregated areas (formed by the ionic pairs) generate the continuous channels that favor proton transport. The optical and photo-responsive properties were studied by UV-Vis spectroscopy, demonstrating that the azobenzene moieties of the ionic LC undergo reversible (E)-to-(Z) isomerization by irradiation with UV light. Interestingly, this (E)-to-(Z) photoisomerization results in a decrease of the proton conductivity values since the bent-shaped (Z)-isomer disrupts the lamellar LC phase. This isomerization process is totally reversible and leads to an ionic LC material with unique photo-switchable proton conductive properties.

Liquid crystal (LC) pillar[n]arenes have been barely explored due to their time-consuming and complicated synthesis, despite their promising properties for metal-ion separation, drug delivery, or surface functionalization. Herein, we report an easy and reliable method to functionalize pillar[n]arene macrocycles through electrostatic interactions. These ionic materials were prepared by ionically functionalizing a pillar[n]arene containing ten amine terminal groups with six different carboxylic acids. This supramolecular approach results in ionic pillar[n]arenes which self-organize into LC phases with good proton-conducting properties. Moreover, ionic functionalization provides a new amphiphilic character to the pillar[n]arenes, which self-assemble in water to produce a variety of nanoobjects (i.e., spherical or cylindrical micelles, vesicles, solid nanospheres, or nanotubes) that are capable of encapsulating a model hydrophobic drug. Interestingly, the presence of coumarin moieties in the chemical structure of the ionic pillar[n]arenes results in self-organized materials with light-responsive properties due to the ability of coumarins to undergo photo-induced [2+2] cycloaddition. In particular, we demonstrate that coumarin pohotodimerization can be employed to fabricate mechanically stable proton-conductive LC materials, as well as to obtain photo-responsive nanocarriers with light-induced release of encapsulated molecules.