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Este estudio analiza la publicidad de juguetes emitida en España durante el periodo de Navidad 2014/15 con la finalidad de iniciar una revisión cuantitativa de la representación de la familia en los anuncios. En su primera parte revisa los conceptos de infancia y niñez, los relaciona con el concepto de socialización y presenta un breve análisis del fenómeno publicitario. Los resultados evalúan la presencia de los tipos de emociones, valores y acciones asociados al género de los personajes y cuantifica la frecuencia de aparición de padres y abuelos en los anuncios de juguetes dirigidos a niños. La baja presencia de estos establece una discusión acerca del rol de dichos personajes como figuras de referencia y autoridad necesarias en el desarrollo infantil. También se plantea una reflexión final sobre la homogeneidad de las representaciones de los géneros asociadas a los roles de los personajes, tanto de adultos como niños. Finalmente se justifica el interés por ampliar el estudio hacia un escenario internacional, que permita comprobar los grados de similitud y contraste en dichas representaciones como forma de contribuir a la comprensión y visualización de la familia en los discursos publicitarios.

A large number of material and process parameters affect both the part quality and the process performance in pressure die-casting (PDC) processes. The complex relations between most of these variables make PDC process optimisation a difficult issue which has been widely studied for many years. Although there are several analytical and numerical models to optimise certain process parameters, it is difficult to establish a specific operational configuration for PDC machines that ensures the joint optimisation of these variables. Therefore, in this study, some of these optimisation models have been implemented in a Decision Support System (DSS) that allows us to define an operational region that establishes a setup of machine parameters that ensures the manufacture of quality parts. By using this DSS, the user can set the values of the input variables related to the casting material, the die, or the casting machine. Then the corresponding calculations are made by the system and the results are expressed in terms of certain output variables such as the maximum filling time, maximum filling fraction, or the plunger velocity profile among others. The DSS allows the user to estimate the influence between input and output variables and find proper values for the input variables to achieve an optimum operational range. Consequently, improved process performance can be achieved taking into account productivity, part quality, and economic aspects.

Melatonin is crucial in reproduction due its antioxidant, hormonal, and paracrine action. Melatonin membrane receptors (MT1/MT2) have been confirmed on spermatozoa from several species, but functionality studies are scarce. To clarify their role in ruminants as reproductive models, bull (Bos taurus, non-seasonal) and red deer (Cervus elaphus, highly seasonal) spermatozoa were analyzed after 4 h of incubation (38 °C, capacitating media) in 10 nM melatonin, MT1/MT2 agonists (phenylmelatonin and 8M-PDOT), and antagonists (luzindole and 4P-PDOT). Motility and functionality (flow cytometry: viability, intracellular calcium, capacitation status, reactive oxygen species (ROS) production, and acrosomal and mitochondrial status) were assessed. In bull, MT1 was related to sperm viability preservation, whereas MT2 could modulate cell functionality to prevent excess ROS produced by the mitochondria; this action could have a role in modulating sperm capacitation. Deer spermatozoa showed resistance to melatonin and receptor activation, possibly because the samples were of epididymal origin and collected at the breeding season’s peak, with high circulating melatonin. However, receptors could be involved in mitochondrial protection. Therefore, melatonin receptors are functional in the spermatozoa from bull and deer, with different activities. These species offer models differing from traditional laboratory experimental animals on the role of melatonin in sperm biology.

Sperm capacitation is a stepwise complex biochemical process towards fertilization. It includes a crucial early calcium (Ca2+) transport mediated by CatSper channels and Canonical Transient Potential Channels (TRPC). We studied the relative abundance of mRNA transcripts changes of the CatSper β, γ and δ subunits and TRPC-channels 1, 3, 4, 6 and 7 in pig spermatozoa, after triggering in vitro capacitation by bicarbonate ions at levels present in vivo at the fertilization site. For this purpose, we analyzedfive5 ejaculate pools (from three fertile adult boars) before (control-fresh samples) and after in vitro exposure to capacitation conditions (37 mM NaHCO3, 2.25 mM CaCl2, 2 mM caffeine, 0.5% bovine serum albumin and 310 mM lactose) at 38 °C, 5% CO2 for 30 min. In vitro capacitation using bicarbonate elicits an increase in the relative abundance of mRNA transcripts of almost all studied Ca2+ channels, except CatSper-δ and TRPC1 (significantly reduced). These findings open new avenues of research to identify the specific role of each channel in boar sperm capacitation and elucidate the physiological meaning of the changes on sperm mRNA cargo.

Este artículo plantea tres objetivos. El primero, saber si el origen social influye en la probabilidad de estar parado y, en segundo lugar, en caso de que se sea así, averiguar si esa influencia se mantiene incluso comparando a individuos con el mismo nivel educativo. El tercer objetivo es determinar si el efecto del origen social en el paro varía en cada nivel de estudios. Para ello se han manejado 49 encuestas del CIS llevadas a cabo entre 2013 y 2017, y se ha aplicado un modelo de probabilidad lineal. Los resultados muestran que hay un efecto claro del origen social sobre el paro y que este efecto se produce sobre todo indirectamente, a través del nivel educativo. No obstante, el origen social sigue teniendo un efecto incluso controlando por la educación entre los licenciados o graduados universitarios (no ingenieros) y los que tienen la secundaria inicial o menos.

Iron is an essential micronutrient for all eukaryotic organisms because it participates as a redox cofactor in many cellular processes. However, excess iron can damage cells since it promotes the generation of reactive oxygen species. The budding yeast Saccharomyces cerevisiae has been used as a model organism to study the adaptation of eukaryotic cells to changes in iron availability. Upon iron deficiency, yeast utilizes two transcription factors, Aft1 and Aft2, to activate the expression of a set of genes known as the iron regulon, which are implicated in iron uptake, recycling and mobilization. Moreover, Aft1 and Aft2 activate the expression of Cth2, an mRNA-binding protein that limits the expression of genes encoding for iron-containing proteins or that participate in iron-using processes. Cth2 contributes to prioritize iron utilization in particular pathways over other highly iron-consuming and non-essential processes including mitochondrial respiration. Recent studies have revealed that iron deficiency also alters many other metabolic routes including amino acid and lipid synthesis, the mitochondrial retrograde response, transcription, translation and deoxyribonucleotide synthesis; and activates the DNA damage and general stress responses. At high iron levels, the yeast Yap5, Msn2, and Msn4 transcription factors activate the expression of a vacuolar iron importer called Ccc1, which is the most important high-iron protecting factor devoted to detoxify excess cytosolic iron that is stored into the vacuole for its mobilization upon scarcity. The complete sequencing and annotation of many yeast genomes is starting to unveil the diversity and evolution of the iron homeostasis network in this species.

El fenómeno de los menores influyentes en las plataformas de vídeos experimenta un crecimiento imparable en el consumo, la actividad, la presencia de marcas alrededor de estos contenidos y la capacidad de influencia y transformación social de algunos contenidos. Todo ello también incrementa la problemática derivada, por ser un fenómeno parcialmente previsto en la normativa vigente. Existen nuevos y emergentes retos investigadores para el colectivo de los públicos involucrados: menores creadores de contenidos, padres, madres o tutores legales, profesionales del medio YouTube, seguidores, docentes e investigadores y sociedad en general. Ser youtuber es una de las cinco profesiones más deseadas por los niños españoles (Adecco, 2021). Inmersos en la cultura de la participación (Jenkins, 2006; Aparici y Osuna-Acedo, 2013), YouTube ofrece un espacio accesible donde almacenar estos contenidos y permite a los usuarios interactuar con ellos al buscar, compartir y comentar contenidos audiovisuales alrededor de los cuales dichos usuarios construyen comunidades. Los/as menores creadores expresan su identidad con vídeos que reflejan su forma de ver la vida e influyen en la comunidad de seguidores (Tur-Viñes, Nuñez- Gómez y González-Río, 2018). Este sociosistema se basa en contenidos audiovisuales con marcadas implicaciones para la publicidad y su regulación y autorregulación. El presente monográfico cumple el objetivo de acercarse al marco normativo y a las iniciativas de autorregulación sobre los menores creadores de contenidos, desde una perspectiva audiovisual, publicitaria y educomunicativa. Este fenómeno ha suscitado la necesidad de reformar normativas de la Unión Europea como la Directiva de Comercio Electrónico, la Directiva de Servicios de Medios Audiovisuales y el Reglamento de Protección de Datos (GDPR), de cambiar políticas en plataformas para ajustarlas a la normativa COPPA -en el caso de EEUU-y de redactar códigos de autorregulación por diversas entidades, muchas veces impulsadas por la interacción, o como resultado de, las acciones de entes regulatorios como la FTC en los Estados Unidos. En torno a dicho marco normativo, el presente monográfico aborda temas relacionados con la publicidad, la protección de los datos personales y de la privacidad y las responsabilidades de los diferentes sujetos que participan de esta realidad, así como el papel de las Administraciones y de los padres de los menores.

Two-dimensional (2D) materials have promising applications in optoelectronics, photonics, and quantum technologies. However, their intrinsically low light absorption limits their performance, and potential devices must be accurately engineered for optimal operation. Here, we apply a transfer matrix-based source-term method to optimize light absorption and emission in 2D materials and related devices in weak and strong coupling regimes. The implemented analytical model accurately accounts for experimental results reported for representative 2D materials such as graphene and MoS2. The model has been extended to propose structures to optimize light emission by exciton recombination in MoS2 single layers, light extraction from arbitrarily oriented dipole monolayers, and single-photon emission in 2D materials. Also, it has been successfully applied to retrieve exciton-cavity interaction parameters from MoS2 microcavity experiments. The present model appears as a powerful and versatile tool for the design of new optoelectronic devices based on 2D semiconductors such as quantum light sources and polariton lasers.

Sirtuins are involved in the regulation of responses to diverse types of cellular stress. Here the authors describe the SirT6-dependent cysteine monoubiquitination of the histone methyltransferase Suv39h1 as part of a regulatory circuit for the NF-κB pathway.

Field’s metal, a low-melting-point eutectic alloy composed of 51% In, 32.5 Bi% and 16.5% Sn by weight and with a melting temperature of 333 K, is widely used as liquid metal coolant in advanced nuclear reactors and in electro–magneto–hydrodynamic two-phase flow loops. However, its rheological and wetting properties in liquid state make this metal suitable for the formation of droplets and other structures for application in microfabrication. As with other low-melting-point metal alloys, in the presence of air, Field’s metal has an oxide film on its surface, which provides a degree of malleability and stability. In this paper, the viscoelastic properties of Field’s metal oxide skin were studied in a parallel-plate rheometer, while surface tension and solidification and contact angles were determined using drop shape analysis techniques.

This article analyses the employability of university graduates in Spain, in terms of both the quan­tity and quality of employment. Regarding quantity, graduate employment rates are higher than those for people with other education levels. Furthermore, both in times of crisis and of bonanza, graduates are more protected against unemployment. This is fundamentally due to the fact that they work in sectors and occupations that are less exposed to cycles. Regarding the quality of their jobs, graduates are less likely to have fixed-term contracts, although not much less than those who have vocational training or upper secondary education. On the other hand, depending on how it is measured, the proportion of underemployed university graduates is between 26% and 38%. The article also confirms that the salaries of university graduates are higher than of those who have other levels of education; but they have decreased considerably over the last two decades, especially in the last bonanza period.

(ES) Este artículo expone una breve perspectiva de las leyes que han guiado el sistema educativo español desde mediados del siglo XIX hasta principios del XXI, y propone una serie de posibles medidas que pueden aplicarse para la corrección del sistema educativo español, en la etapa de la enseñanza secundaria obligatoria. Tal propuesta se basa en el análisis del sistema educativo en España y de lo que a nuestro juicio supone un desacierto de las políticas educativas en los últimos años. Del conjunto de medidas para la mejora del sistema propuestas eliminamos las que supongan una fuerte inversión económica desde las arcas públicas. Son, por lo tanto, medidas que no afectan a los medios invertidos, sino medidas de tipo curricular y organizativo. (EN) This article presents a brief perspective of the laws that have guided the Spanish education system since the mid 19th century until the beginning of the 21st, and proposes a number of possible measures that can be applied to the correction of the Spanish educational system, in the stage of compulsory secondary education. Such a proposal is based on the analysis of the educational system in Spain and what in our view is a mistake of the educational policies in recent years. The set of proposed measures for the improvement of the system remove which pose a major economic investment from the public purse. They are, therefore, measures that do not affect the means invested, but measures of curricular and organizational type.