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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.

The rampant evolution of resistance in Plasmodium to all existing antimalarial drugs calls for the development of improved therapeutic compounds and of adequate targeted delivery strategies for them. Loading antimalarials in nanocarriers specifically targeted to the parasite will contribute to the administration of lower overall doses, with reduced side effects for the patient, and of higher local amounts to parasitized cells for an increased lethality toward the pathogen. Here, we report the development of dendronized hyperbranched polymers (DHPs), with capacity for antimalarial loading, that are coated with heparin for their specific targeting to red blood cells parasitized by Plasmodium falciparum. The resulting DHP–heparin complexes exhibit the intrinsic antimalarial activity of heparin, with an IC50 of ca. 400 nM, added to its specific targeting to P. falciparum-infected (vs noninfected) erythrocytes. DHP–heparin nanocarriers represent a potentially interesting contribution to the limited family of structures described so far for the loading and targeted delivery of current and future antimalarial compounds.

The purpose of the present study is to delve into the process of personal management of digital information among Spanish university students in their final year and to analyze whether there are similarities or differences regarding students’ gender. A non-experimental methodological design has been implemented of an exploratory type and based on a questionnaire as a single data collection instrument. The instrument was validated by means of experts’ judgement, cognitive interview, and construct validity. A total of 2,054 students’ surveys were collected, sourced from all areas of knowledge, in 75 public and private universities. These surveys made it possible to obtain information about the information search, selection, organization, processing, and creation processes. The results revealed that university students have a positive self-concept about their own competence for personal management of information. However, they fail to take advantage of all the possibilities that the digital world offers them. Women search the Internet for more diverse resources than men. They have better judgment when it comes to selecting and processing the information they need. Male students rely more often than female ones on digital mediums when organizing and creating information and choose to publish the information in less complex and more popular formats than their female counterparts. The conclusions of the present study match those of the majority of reviewed studies, namely regarding the organization of information, contextual and social factors which influence the management of information, such as third-party support, and also in relation to the increasing implementation of digital technologies in information management processes., El propósito del presente estudio es profundizar en el proceso de gestión personal de la información digital por parte de los estudiantes universitarios españoles en su último año de carrera y analizar si existen similitudes o diferencias según el género de los estudiantes. Se ha aplicado un diseño metodológico no-experimental de carácter exploratorio y basado en un cuestionario como único instrumento para la recogida de datos. El instrumento fue validado a través de la opinión de expertos, la entrevista cognitiva y la validez del constructo. Se recabaron un total de 2.054 encuestas de estudiantes, procedentes de todas las áreas de conocimiento, en 75 universidades públicas y privadas. Dichas encuestas permitieron obtener datos acerca de la búsqueda de información, la selección, la organización y el procesado, así como los procesos de creación de la misma. Los resultados revelaron que los estudiantes universitarios tienen un autoconcepto positivo acerca de su propia competencia para la gestión personal de la información. Sin embargo, no logran aprovechar todas las posibilidades que les ofrece el mundo digital. Las mujeres buscan recursos más diversos que los hombres en Internet. Tienen más criterio a la hora de seleccionar y procesar la información que necesitan. Los estudiantes confían con mucha mayor frecuencia en los medios digitales que las estudiantes cuando organizan y crean información, y optan por publicar información en formatos menos complejos y más populares que sus homólogas femeninas. Las conclusiones del presente estudio coinciden con los de la mayoría de los estudios revisados, concretamente por lo que respecta a la organización de la información y los factores contextuales y sociales que influyen en la gestión de ésta, tales como el apoyo de terceros, y también en relación con la creciente implementación de tecnologías digitales en los procesos de gestión de la información.

El carcinoma renal de células claras es el subtipo histológico más frecuente de los tumores renales, con gran capacidad de provocar metástasis a distancia, siendo el origen más frecuente de metástasis en la glándula tiroidea. Normalmente, las metástasis a este nivel se diagnostican de forma tardía, puesto que la mayoría son de pequeño tamaño y no provocan síntomas, pudiendo ser confundidas al inicio por nódulos benignos. El diagnóstico definitivo se realiza mediante estudio histológico. En cuanto al tratamiento, la cirugía suele ser de elección, salvo en casos diseminados. Se presenta el caso de una paciente mujer de 61 años intervenida de nefrectomía y suprarrenalectomía izquierda por carcinoma renal de células claras tras hallazgo incidental posthemitiroidectomia izquierda por nódulo Bethesda III con AP definitiva de metástasis tiroidea de origen renal., Renal clear cell carcinoma is the most common histological subtype of renal tumors, with a great ability to cause metástasis at distance, this latter being the most frequent origin of metástasis in the thyroid gland. Typically, metástasis at this level are diagnosed late, since most are small, do not cause symptoms, and may initially be confused with benign nodules. The definitive diagnosis is made by histological study. With regard to treatment, surgery is usually the better option, except for disseminated cases. Clinical case of a 61 years old female patient who underwent nephrectomy and left adrenalectomy for renal clear cell carcinoma after an incidental finding post left hemithyroidectomy for Bethesda III nodule with definitive PA of thyroid metástasis of renal origin.

Anaplastic thyroid carcinoma is a rare entity (5-10% thyroid cancers) but it is one of the most lethal malignancies. It is usually diagnosed late and it is unresectable at that time. The definitive diagnosis is realized with a histological study. Regarding treatment, the combination of surgery, radiation therapy and chemotherapy is the one that obtains the best results. We reported a case of a 69-year-old female patient who underwent left hemithyroidectomy for a thyroid nodule initially with fine needle biopsy of follicular proliferation and with definitive pathology after excision of papillary thyroid carcinoma. Totalizing surgery was performed with a histological result of anaplastic thyroid carcinoma., El carcinoma anaplásico de tiroides es poco común (5-10% cánceres de tiroides) pero se trata de una de las neoplasias malignas más letales. Normalmente se diagnostica de forma tardía siendo en ese momento irresecable. El diagnóstico definitivo se realiza mediante estudio histológico. En cuanto al tratamiento, la combinación de cirugía, radioterapia y quimioterapia es la que obtiene mejores resultados. Se presenta el caso de una paciente mujer de 69 años intervenida de hemitiroidectomía izquierda por nódulo tiroideo inicialmente con PAAF de proliferación folicular y con anatomía patológica definitiva tras la exéresis de carcinoma papilar de tiroides. Se realiza cirugía totalizadora con resultado histológico de carcinoma anaplásico de tiroides.

A series of six polybenzylic dendrons with an alkynyl focal point were synthesized for their incorporation to gold nanoparticles. Five of these compounds showed columnar mesomorphism in a wide range of temperatures. These dendrons were reacted with gold nanoparticles stabilized with a combination of a dodecanethiol and 11-azidoundecane-1-thiol. The azido group of the last compound allowed the functionalization of the nanoparticles with the six polybenzylic dendrons by 1,3-dipolar cycloaddition between their alkynyl groups and the terminal azido groups of the thiols. A high efficiency of the cycloaddition process (47–69%) was confirmed by several experimental techniques and no decomposition or aggregation phenomena were detected in the dendron-coated nanoparticles. The involved mechanism and the resulting percentage composition of the final materials are discussed. The results of the ulterior growth of the nanoparticles by thermal treatment are influenced by the size and the shape of the dendron and the temperature of the process. The structures of the final nanoparticles were investigated by TEM, DSC, TGA, NMR and UV-Vis spectroscopy. These nanoparticles do not show liquid crystal properties. However, a melting process between a crystalline and a fluid phase is observed. In the solid phase, the nanomaterials prepared show a short-range interaction between nanoparticles with a 2D local hexagonal order. A near-field effect was observed in the UV-vis spectra by coupling of different surface plasmon resonance bands (SPR) probably due to the short-range interactions. The main novelty of this work lies in the scarcity of previous studies of gold nanoparticles coated with dendrons forming themselves columnar mesophases. Most of the studies reported in the literature deal with gold nanoparticles coated with calamitic mesogens. Additionally, the effect of the thermal treatment, which in a previous paper was shown to increase the mean size of the nanoparticles without increas

Gene therapy has become a relevant tool in the biomedical field to treat or even prevent some diseases. The effective delivery of genetic material into the cell remains a crucial step to succeed in this purpose. In the search for efficient non-viral vectors, a series of amino-terminated dendronized hyperbranched polymers (DHPs) of different generations based either on bis-MPA or bis-GMPA have been designed. All of them have demonstrated an accurate ability to complex two types of genetic materials, a plasmid DNA and a siGFP, yielding dendriplexes. Moreover, some of them have proved to be able to deliver the genetic material inside the cells, resulting in the effective accomplishment of the desired genetic modification and improving the activity of some commercial transfection reagents. Different cell lines, including cancer and mesenchymal stem cells, have been studied here to evaluate the ability of DHPs as vectors for transfection. Treatments based on mesenchymal stem cells are gaining importance due to their pluripotency. Thus, it is of special relevance to introduce a genetic modification into a mesenchymal cell line as it allows it to act over a wide spectrum of tissues after inducing cellular differentiation.

The purpose of the present study is to delve into the process of personal management of digital information among Spanish university students in their final year and to analyze whether there are similarities or differences regarding students’ gender. A non-experimental methodological design has been implemented of an exploratory type and based on a questionnaire as a single data collection instrument. The instrument was validated by means of experts’ judgement, cognitive interview, and construct validity. A total of 2,054 students’ surveys were collected, sourced from all areas of knowledge, in 75 public and private universities. These surveys made it possible to obtain information about the information search, selection, organization, processing, and creation processes. The results revealed that university students have a positive self-concept about their own competence for personal management of information. However, they fail to take advantage of all the possibilities that the digital world offers them. Women search the Internet for more diverse resources than men. They have better judgment when it comes to selecting and processing the information they need. Male students rely more often than female ones on digital mediums when organizing and creating information and choose to publish the information in less complex and more popular formats than their female counterparts. The conclusions of the present study match those of the majority of reviewed studies, namely regarding the organization of information, contextual and social factors which influence the management of information, such as third-party support, and also in relation to the increasing implementation of digital technologies in information management processes., El propósito del presente estudio es profundizar en el proceso de gestión personal de la información digital por parte de los estudiantes universitarios españoles en su último año de carrera y analizar si existen similitudes o diferencias según el género de los estudiantes. Se ha aplicado un diseño metodológico no-experimental de carácter exploratorio y basado en un cuestionario como único instrumento para la recogida de datos. El instrumento fue validado a través de la opinión de expertos, la entrevista cognitiva y la validez del constructo. Se recabaron un total de 2.054 encuestas de estudiantes, procedentes de todas las áreas de conocimiento, en 75 universidades públicas y privadas. Dichas encuestas permitieron obtener datos acerca de la búsqueda de información, la selección, la organización y el procesado, así como los procesos de creación de la misma. Los resultados revelaron que los estudiantes universitarios tienen un autoconcepto positivo acerca de su propia competencia para la gestión personal de la información. Sin embargo, no logran aprovechar todas las posibilidades que les ofrece el mundo digital. Las mujeres buscan recursos más diversos que los hombres en Internet. Tienen más criterio a la hora de seleccionar y procesar la información que necesitan. Los estudiantes confían con mucha mayor frecuencia en los medios digitales que las estudiantes cuando organizan y crean información, y optan por publicar información en formatos menos complejos y más populares que sus homólogas femeninas. Las conclusiones del presente estudio coinciden con los de la mayoría de los estudios revisados, concretamente por lo que respecta a la organización de la información y los factores contextuales y sociales que influyen en la gestión de ésta, tales como el apoyo de terceros, y también en relación con la creciente implementación de tecnologías digitales en los procesos de gestión de la información.

When a molecule is bound to external electrodes by terminal anchor groups, the latter are of paramount importance in determining the electrical conductance of the resulting molecular junction. Here we explore the electrical properties of a molecule with bidentate anchor groups, namely 4,4′-(1,4-phenylenebis(ethyne-2,1-diyl))bis(pyridin-2-amine), in both large area devices and at the single molecule level. We find an electrical conductance of 0.6 × 10−4G0 and 1.2 × 10−4G0 for the monolayer and for the single molecule, respectively. These values are approximately one order of magnitude higher than those reported for monodentate materials having the same molecular skeleton. A combination of theory and experiments is employed to understand the conductance of monolayer and single molecule electrical junctions featuring this new multidentate anchor group. Our results demonstrate that the molecule has a tilt angle of 30° with respect to the normal to the surface in the monolayer, while the break-off length in the single molecule junction occurs for molecules having a tilt angle estimated as 40°, which would account for the difference in their conductance values per molecule. The bidentate 2-aminepyridine anchor is of general interest as a contact group, since this terminal functionalized aromatic ring favours binding of the adsorbate to the metal contact resulting in enhanced conductance values.

Biomaterials for antimalarial drug transport still need to be investigated in order to attain nanocarriers that can tackle essential issues related to malaria treatment, e.g. complying with size requirements and targeting specificity for their entry into Plasmodium-infected red blood cells (pRBCs), and limiting premature drug elimination or drug resistance evolution. Two types of dendritic macromolecule that can form vehicles suitable for antimalarial drug transport are herein explored. A new hybrid dendritic-linear-dendritic block copolymer based on Pluronic® F127 and amino terminated 2,2′-bis(glycyloxymethyl)propionic acid dendrons with a poly(ester amide) skeleton (HDLDBC-bGMPA) and an amino terminated dendronized hyperbranched polymer with a polyester skeleton derived from 2,2′-bis(hydroxymethyl)propionic acid (DHP-bMPA) have provided self-assembled and unimolecular micelles. Both types of micelle carrier are biocompatible and exhibit appropriate sizes to enter into pRBCs. Targeting studies have revealed different behaviors for each nanocarrier that may open new perspectives for antimalarial therapeutic approaches. Whereas DHP-bMPA exhibits a clear targeting specificity for pRBCs, HDLDBC-bGMPA is incorporated by all erythrocytes. It has also been observed that DHP-bMPA and HDLDBC-bGMPA incorporate into human umbilical vein endothelial cells with different subcellular localization, i.e. cytosolic and nuclear, respectively. Drug loading capacity and encapsulation efficiencies for the antimalarial compounds chloroquine, primaquine and quinacrine ranging from 30% to 60% have been determined for both carriers. The resulting drug-loaded nanocarriers have been tested for their capacity to inhibit Plasmodium growth in in vitro and in vivo assays.

We report a new family of liquid crystalline porphyrin-core dendrimers with coumarin units at the periphery of the dendrimer. These compounds have been prepared by copper-catalyzed azide–alkyne “click” cycloaddition (CuAAC). The mesomorphic properties have been investigated via polarized optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The peripheral coumarin units play a key role in the liquid crystal behavior, contributing to the appearance of discotic nematic mesophases with hole mobility values among the highest values reported for discotic liquid crystals (of the order of 1 cm2 V−1 s−1). It has also been demonstrated that excitation of the coumarin moieties leads to energy transfer (antenna effect) to the luminescent porphyrin core. Therefore, this strategy, which involves ‘click’ chemistry, has been proven to be a powerful and elegant synthetic tool for the preparation of optoelectronic materials based on complex dendritic architectures.

Actualmente en un mundo exigente y competitivo, las empresas del sector automotriz se han visto en la obligación de implementar dentro de sus prácticas herramientas de mejora para desarrollar productos a menores costos y cumpliendo con los objetivos de calidad propuestos. Una de las herramientas más usadas dentro del sector es el APQP (Advanced Product Quality Planning), esta es una metodología que tiene como objetivo desarrollar productos que satisfagan las necesidades del cliente, ya sea con un nuevo producto o con uno ya existente dentro de la organización. El objetivo de este estudio es determinar, mediante una revisión de la literatura, las principales características y elementos del APQP, el impacto que genera su implementación además de las ventajas, desventajas y dificultades que se pueden llegar a presentar al momento de poner en marcha la metodología.

In the face of the COVID-19 pandemic, millions of students have been affected by the closure of educational institutions. This has forced a shift from face-to-face to distance education, facing numerous emergency educational measures, such as online assessment. This study aims to present a systematic review of the literature on the impact of assessment in higher education during the pandemic. The study has followed the methodology set out in the PRISMA statement, and includes 13 studies selected from a total of 51. The results indicate that faculty and students have faced numerous challenges in moving to virtual environments; on the faculty side the lack of training in online assessment techniques is the main problem, on the students’ side there is dishonesty and misconduct. However, it is concluded that continuous assessment, not focused on exams, but in a more qualitative way is the best way to assess at a distance.

Actualmente en un mundo exigente y competitivo, las empresas del sector automotriz se han visto en la obligación de implementar dentro de sus prácticas herramientas de mejora para desarrollar productos a menores costos y cumpliendo con los objetivos de calidad propuestos. Una de las herramientas más usadas dentro del sector es el APQP (Advanced Product Quality Planning), esta es una metodología que tiene como objetivo desarrollar productos que satisfagan las necesidades del cliente, ya sea con un nuevo producto o con uno ya existente dentro de la organización. El objetivo de este estudio es determinar, mediante una revisión de la literatura, las principales características y elementos del APQP, el impacto que genera su implementación además de las ventajas, desventajas y dificultades que se pueden llegar a presentar al momento de poner en marcha la metodología.

Actualmente en un mundo exigente y competitivo, las empresas del sector automotriz se han visto en la obligación de implementar dentro de sus prácticas herramientas de mejora para desarrollar productos a menores costos y cumpliendo con los objetivos de calidad propuestos. Una de las herramientas más usadas dentro del sector es el APQP (Advanced Product Quality Planning), esta es una metodología que tiene como objetivo desarrollar productos que satisfagan las necesidades del cliente, ya sea con un nuevo producto o con uno ya existente dentro de la organización. El objetivo de este estudio es determinar, mediante una revisión de la literatura, las principales características y elementos del APQP, el impacto que genera su implementación además de las ventajas, desventajas y dificultades que se pueden llegar a presentar al momento de poner en marcha la metodología.

In the face of the COVID-19 pandemic, millions of students have been affected by the closure of educational institutions. This has forced a shift from face-to-face to distance education, facing numerous emergency educational measures, such as online assessment. This study aims to present a systematic review of the literature on the impact of assessment in higher education during the pandemic. The study has followed the methodology set out in the PRISMA statement, and includes 13 studies selected from a total of 51. The results indicate that faculty and students have faced numerous challenges in moving to virtual environments; on the faculty side the lack of training in online assessment techniques is the main problem, on the students’ side there is dishonesty and misconduct. However, it is concluded that continuous assessment, not focused on exams, but in a more qualitative way is the best way to assess at a distance.

Actualmente en un mundo exigente y competitivo, las empresas del sector automotriz se han visto en la obligación de implementar dentro de sus prácticas herramientas de mejora para desarrollar productos a menores costos y cumpliendo con los objetivos de calidad propuestos. Una de las herramientas más usadas dentro del sector es el APQP (Advanced Product Quality Planning), esta es una metodología que tiene como objetivo desarrollar productos que satisfagan las necesidades del cliente, ya sea con un nuevo producto o con uno ya existente dentro de la organización. El objetivo de este estudio es determinar, mediante una revisión de la literatura, las principales características y elementos del APQP, el impacto que genera su implementación además de las ventajas, desventajas y dificultades que se pueden llegar a presentar al momento de poner en marcha la metodología.

In the face of the COVID-19 pandemic, millions of students have been affected by the closure of educational institutions. This has forced a shift from face-to-face to distance education, facing numerous emergency educational measures, such as online assessment. This study aims to present a systematic review of the literature on the impact of assessment in higher education during the pandemic. The study has followed the methodology set out in the PRISMA statement, and includes 13 studies selected from a total of 51. The results indicate that faculty and students have faced numerous challenges in moving to virtual environments; on the faculty side the lack of training in online assessment techniques is the main problem, on the students’ side there is dishonesty and misconduct. However, it is concluded that continuous assessment, not focused on exams, but in a more qualitative way is the best way to assess at a distance.

En el marco de las posibilidades ofrecidas por la nanotecnología, los materiales dendríticos presentan un gran interés debido a su gran potencial como transportadores de moléculas de diversa naturaleza. En este sentido, los dendrímeros y materiales derivados han sido ampliamente utilizados en biomedicina como transportadores de fármacos y de material genético. Dentro de la gran variedad de dendrímeros existente, la presente tesis doctoral se ha centrado en el estudio de materiales dendríticos basados en el ácido 2,2´-bis(hidroximetil)propiónico (bis-MPA) y el ácido 2,2’-bis(gliciloximetil)propiónico (bis-GMPA). Éste último incluye grupos amida internos potencialmente capaces de establecer puentes de hidrógeno con las moléculas que aloje en su interior y reforzar de esta manera su interacción para una encapsulación más eficiente. Basados en estas unidades mínimas, se han diseñado dos tipos de materiales dendríticos: dendrímeros de tipo Jano anfífilos y polímeros hiperramificados dendronizados (DHPs, por sus siglas en inglés). Los dendrímeros tipo Jano anfífilos combinan una cara hidrófila con una lipófila y en esta tesis doctoral, se ha alternado la composición bis-MPA/ bis-GMPA entre ambas caras. Además, también se ha modificado el número de cadenas lipófilas (2 ó 4), alterando de esta manera el balance hidrófilo del dendrímero resultante. En concreto, los dendrímeros Jano sintetizados han sido: - (NH3+)8[GMPA]-[MPA](C17)2 que consiste en un dendrón hidrófilo de bis-GMPA 3ª generación y un dendrón lipófilo de bis-MPA de 1ª generación, - (NH3+)8[GMPA]-[MPA](C17)4 que consiste en un dendrón hidrófilo de bis-GMPA 3ª generación y un dendrón lipófilo de bis-MPA de 2ª generación, - (NH3+)8[MPA]-[GMPA](C17)2 que consiste en un dendrón hidrófilo de bis-MPA 3ª generación y un dendrón lipófilo de bis-GMPA de 1ª generación, - (NH3+)8[MPA]-[GMPA](C17)4 que consiste en un dendrón hidrófilo de bis-MPA 3ª generación y un dendrón lipófilo de bis-GMPA de 2ª generación. Por otra part

Deposition of the top-contact electrode to create large-area electrode | monolayer | electrode junctions represents a contemporary challenge to the integration of molecular electronic phenomena into device structures. Here, a top contact electrode is formed on top of an organic monolayer over a large area (cm2) by two simple, sequential self-assembly steps. Initial self-assembly of 4,4′-(1,4-phenylenebis(ethyne-2,1-diyl))dianiline onto gold-on-glass substrates gives high-quality monolayers. The exposed amine functionality is subsequently used to anchor uncapped gold nanoparticles deposited in a second self-assembly step. These uncapped gold nanoparticles are prepared by thermolysis of lipoic acid stabilized gold nanoclusters and contain gold oxide (≈9%) that provides stability in the absence of an organic capping ligand. This two-step procedure results in full coverage of the monolayer by the densely packed gold nanoparticles, which spontaneously condense to give a semi-continuous film. The electrical properties of these junctions are determined from I–V curves, revealing uniform electrical response and absence of metallic short-circuits or evidence of damage to the underlying molecular monolayer. These promising electrical characteristics suggest that the deposition of uncapped gold nanoparticles on suitably functionalized molecular monolayers provides a path for the fabrication of molecular electronic devices using simple methodologies.

Highly sensitive magnetometry reveals paramagnetism in dendrimer-coated gold nanoparticles. Different types of such nanoparticles, as a result of (i) functionalizing with two distinct Percec-type dendrons, linked to gold via dodecanethiol groups, and (ii) postsynthesis annealing in a solvent-free environment that further promotes their growth have been prepared. Ultimately, for each of the two functionalization configurations, we obtain highly monodisperse and stable nanoparticles of two different sizes, with spherical shape. These characteristics allow singling out the source of the measured paramagnetic signals as exclusively arising from the undercoordinated gold atoms on the surfaces of the nanoparticles. Bulk gold and the functional groups of the ligands contribute only diamagnetically.

Highly functional macromolecules with a well-defined architecture are the key to designing efficient and smart materials, and these polymeric systems can be tailored for specific applications in a diverse range of fields. Herein, the formation of a new liquid crystalline polymeric network based on the crosslinking of dendrimeric entities by the CuI-catalyzed variant of the Huisgen 1,3-dipolar cycloaddition of azides and alkynes to afford 1,2,3-triazoles is reported. The polymeric material obtained in this way is easy to process and exhibits a variety of properties, which include mesomorphism, viscoelastic behavior, and thermal contraction. The porous microstructure of the polymer network determines its capability to absorb solvent molecules and to encapsulate small molecules, like organic dyes, which can be released easily afterwards. Moreover, all these properties may be easily tuned by modifying the chemical structure of the constituent dendrimers, which makes this system a very interesting one for a number of applications.

Monodisperse dendrimer-coated gold nanoparticles with a spherical shape have been obtained by direct reduction of HAuCl4 with sodium borohydride in the presence of dodecanethiol as a stabilizer and subsequent functionalization by ligand exchange reaction with polybenzylic thiolated dendrons. The substitution pattern of the dendrimeric units plays a fundamental role in the rate of the functionalization exchange process and consequently conditions the size and the polydispersity of the NPs obtained. An ulterior growth process occurs by thermal stimuli (150 °C) in a solvent-free environment. This method, carried out in mild conditions, allows the formation of highly monodisperse gold NPs with different sizes for different time reactions, and we discuss the mechanisms involved in this process. Finally, we demonstrate the chemical composition and stability of our compounds by structural, thermal, and chemical characterization of the samples before and after thermal treatment.

Clinical outcomes of conventional drug combinations are not ideal due to high toxicity to healthy tissues. Cisplatin (CDDP) is the standard component for many cancer treatments, yet its principal dose-limiting side effect is nephrotoxicity. Thus, CDDP is commonly used in combination with other drugs, such as the autophagy inhibitor chloroquine (CQ), to enhance tumor cell killing efficacy and prevent the development of chemoresistance. In addition, nanocarrier-based drug delivery systems can overcome chemotherapy limitations, decreasing side effects and increasing tumor accumulation. The aim of this study was to evaluate the toxicity of CQ and CDDP against tumor and non-tumor cells when used in a combined treatment. For this purpose, two types of micelles based on Pluronic® F127 hybrid dendritic–linear–dendritic block copolymers (HDLDBCs) modified with polyester or poly(esteramide) dendrons derived from 2,2′-bis(hydroxymethyl)propionic acid (HDLDBC-bMPA) or 2,2′-bis(glycyloxymethyl)propionic acid (HDLDBC-bGMPA) were explored as delivery nanocarriers. Our results indicated that the combined treatment with HDLDBC-bMPA(CQ) or HDLDBC-bGMPA(CQ) and CDDP increased cytotoxicity in tumor cells compared to the single treatment with CDDP. Encapsulations demonstrated less short-term cytotoxicity individually or when used in combination compared to the free drugs. However, and more importantly, a low degree of cytotoxicity against non-tumor cells was maintained, even when drugs were given simultaneously.

A study of the solution-phase, solid-state structures of halogen-bonded co-crystals of 1,4-bis(iodoethynyl)benzene (p-BIB) with three salts, namely, decyltrimethylammonium bromide (DTMABr), tetrapropylammonium bromide (TPABr), and tetrabutylammonium bromide (TBABr), has been carried out, along with theoretical calculations. Isothermal titration calorimetry (ITC) showed that the binding constant of bromide with p-BIB in THF is not strongly dependent on the cation, and that the entropic term clearly dominates the enthalpic one in the free energy of binding. In the three crystal structures, the bromide anion acts as a doubly connected node for halogen bonding interactions, which results in linear or angular open chains. The intrachain angles (IBr-I) of the 1D supramolecular polymers based on p-BIB depend on the geometry and size of the cation and vary from 180° for DMTABr to 75° for TBABr. Non-covalent interaction (NCI) analysis of selected motifs and optimized crystals demonstrates that the balance between halogen bonds, hydrogen bonds, and van der Waals interactions, especially type-I halogenhalogen contacts, determines the crystal structures.

In this contribution, pyrazole is identified as an excellent anchoring group capable of forming well-ordered Langmuir–Blodgett (LB) monolayers onto gold substrates. In contrast, the formation of self-assembled (SA) monolayers is prevented due to the extraction of gold atoms from the surface upon the incubation process required for the formation of these films. The electronic coupling strength of pyrazole–gold junctions is explored through evaluation of the electrical properties of LB films incorporating a double pyrazole terminated molecular wire, namely 1,4-bis(1H-pyrazol-4-ylethynyl)benzene, 1; these electrical properties are compared with those of molecules having a similar chemical structure, geometry and length. The conductance value for LB films of 1 is high when the monolayer is transferred from a Langmuir film prepared onto a basic subphase, 1.19 × 10−4G0, as it is more than four times larger than the conductance of the same compound incorporated on a LB film prepared from a water subphase, 0.27 × 10−4G0. These results are interpreted in terms of the deprotonation of the pyrazole group in a basic media that leads to the formation of the pyrazolate (deprotonated pyrazole) moiety. This results in a more efficient electronic coupling with the gold tip of the scanning tunnelling microscope used for film characterization.

Actualmente en un mundo exigente y competitivo, las empresas del sector automotriz se han visto en la obligación de implementar dentro de sus prácticas herramientas de mejora para desarrollar productos a menores costos y cumpliendo con los objetivos de calidad propuestos. Una de las herramientas más usadas dentro del sector es el APQP (Advanced Product Quality Planning), esta es una metodología que tiene como objetivo desarrollar productos que satisfagan las necesidades del cliente, ya sea con un nuevo producto o con uno ya existente dentro de la organización. El objetivo de este estudio es determinar, mediante una revisión de la literatura, las principales características y elementos del APQP, el impacto que genera su implementación además de las ventajas, desventajas y dificultades que se pueden llegar a presentar al momento de poner en marcha la metodología.

The design of efficient drug-delivery vehicles remains a big challenge in materials science. Herein, we describe a novel class of amphiphilic hybrid dendrimers that consist of a poly(amidoamine) (PAMAM) dendritic core functionalized with bisMPA dendrons bearing cholesterol and coumarin moieties. Their self-assembly behavior both in bulk and in water was investigated. All dendrimers exhibited smectic A or hexagonal columnar liquid crystal organizations, depending on the generation of the dendrimer. In water, these dendrimers self-assembled to form stable spherical micelles that could encapsulate Nile Red, a hydrophobic model compound. The cell viability in vitro of the micelles was studied in HeLa cell line, and proved to be non-toxic up to 72 h of incubation. Therefore, these spherical micelles allow the encapsulation of hydrophobic molecules, and at the same time provided fluorescent traceability due to the presence of coumarin units in their chemical structure, demonstrating the potential of these dendrimers as nanocarriers for drug-delivery applications.

Actualmente en un mundo exigente y competitivo, las empresas del sector automotriz se han visto en la obligación de implementar dentro de sus prácticas herramientas de mejora para desarrollar productos a menores costos y cumpliendo con los objetivos de calidad propuestos. Una de las herramientas más usadas dentro del sector es el APQP (Advanced Product Quality Planning), esta es una metodología que tiene como objetivo desarrollar productos que satisfagan las necesidades del cliente, ya sea con un nuevo producto o con uno ya existente dentro de la organización. El objetivo de este estudio es determinar, mediante una revisión de la literatura, las principales características y elementos del APQP, el impacto que genera su implementación además de las ventajas, desventajas y dificultades que se pueden llegar a presentar al momento de poner en marcha la metodología.

Actualmente en un mundo exigente y competitivo, las empresas del sector automotriz se han visto en la obligación de implementar dentro de sus prácticas herramientas de mejora para desarrollar productos a menores costos y cumpliendo con los objetivos de calidad propuestos. Una de las herramientas más usadas dentro del sector es el APQP (Advanced Product Quality Planning), esta es una metodología que tiene como objetivo desarrollar productos que satisfagan las necesidades del cliente, ya sea con un nuevo producto o con uno ya existente dentro de la organización. El objetivo de este estudio es determinar, mediante una revisión de la literatura, las principales características y elementos del APQP, el impacto que genera su implementación además de las ventajas, desventajas y dificultades que se pueden llegar a presentar al momento de poner en marcha la metodología.

Two novel series of ionic liquid crystal polymers that display proton conductive properties are presented here. These materials are based on linear (l-PEI) or branched (b-PEI) poly(ethyleneimine) functionalized with unsymmetrical oxadiazole carboxylic acids derived from 1,3,4-oxadiazole (1,3,4-OXAm) or 1,2,4-oxadiazole (1,2,4-OXAm). The subscript “m” indicates the length of the spacer between the rigid moiety and the carboxyl group, namely m = 4 and 10. The occurrence of proton transfer from the carboxylic acid to the amine groups was confirmed by FTIR and NMR measurements. The liquid crystalline properties were investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and X-ray diffraction (XRD). All ionic complexes displayed enantiotropic smectic A mesophases and in the case of the l-PEI derivatives a nematic phase was also observed at high temperatures. All investigated derivatives presented good proton conductivity values as determined by electrochemical impedance spectroscopy (EIS). Therefore, these ionic LC hyperbranched polymers represent an effective approach for the preparation of proton-transporting polymeric materials with potential applications in electrochemical devices.

We have prepared nanoporous polymers from columnar hexagonal hydrogen-bonded complexes, whose order is fixed by coumarin photoinduced [2 + 2] cycloaddition (photodimerization). Two different hydrogen-bonded complexes were used and consisted of a melamine (M) or tris(triazolyl)triazine (T) derivative acting as central templates and three peripheral carboxylic acids containing coumarin units. These coumarin units were employed for the cross-linking process by photodimerization in order to fix the LC arrangement. Template removal leads to the formation of self-standing nanoporous polymers keeping the columnar hexagonal order. Two nanoporous polymers with different pore diameters were obtained depending on size of the utilized template. These polymers with carboxylic acids at the pore surface demonstrate the ability to selectively adsorb certain molecules depending on their size. Moreover, after base treatment of the nanoporous polymers, they are able to adsorb cationic dyes over anionic and larger cations, demonstrating size- and charge-selective adsorption.

This article provides a bibliographic review of studies undertaken between 2009–2019 regarding the use of Information and Communication Technologies (ICTs) to support the learning of students with disabilities, included in the following databases: Web of Science (WoS,) Scopus, ERIC, SciELO, and Google Scholar. Through a descriptive and quantitative methodology, and using bibliometric maps, the most significant data are presented according to their citation and repercussion index. The results show that ICTs are decisive for student with disabilities but there is evidence of a lack of training by teachers. In this regard, findings show that both the quantity of articles published in the different databases and the citations they receive have a medium-low impact index, as well as a low application of them.

This article provides a bibliographic review of studies undertaken between 2009–2019 regarding the use of Information and Communication Technologies (ICTs) to support the learning of students with disabilities, included in the following databases: Web of Science (WoS,) Scopus, ERIC, SciELO, and Google Scholar. Through a descriptive and quantitative methodology, and using bibliometric maps, the most significant data are presented according to their citation and repercussion index. The results show that ICTs are decisive for student with disabilities but there is evidence of a lack of training by teachers. In this regard, findings show that both the quantity of articles published in the different databases and the citations they receive have a medium-low impact index, as well as a low application of them.