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Inteligencia artificial, ChatGTP y OpenAI son algunos de los términos más buscados en Google en la actualidad según Google Trends (2023). Sin embargo, parte de la concepción de la inteligencia artificial y, sobre todo, de sus posibles aplicaciones tecnológicas en la robótica avanzada, derivan de imaginarios sociales y culturales que se han construido gracias a su representación en la literatura, el cine, las series y los videojuegos. Concretamente, en el cine, películas como Blade Runner (Scott, 1984), Terminator (Cameron, 1984), AI: Artificial Intelligence (Spielberg, 2001), I, Robot (Proyas, 2004) o Ex-Machina (Garland, 2014) han proyectado la imagen de robots inteligentes como amenaza o alteridad al ser humano. El objetivo de este manuscrito es comparar el discurso de las películas españolas Eva (Maíllo, 2011) y Autómata (Ibáñez, 2014) frente al discurso científico de las 20 películas más valoradas según IMDB que incluyen la temática de inteligencia artificial. Para ello, se han triangulado tres perspectivas: el mito de Prometeo (Nieto, 2022), los principios de mitología robótica (Pérez, 2004) y la dicotomía humano - no humano (Gastaka e Iturregi, 2022), lo que ha permitido, siguiendo la metodología de Novoa et al. (2019), extrapolar las características y rasgos que definen el discurso científico de la IA en la cinematografía para poder analizar así el discurso de ambas películas españolas. Los resultados permiten concluir que no existen discrepancias entre la ciencia ficción nacional y la internacional respecto al posicionamiento de la IA como el fin de la humanidad y el diseño de sociedades distópicas y apocalípticas, aunque, particularmente, Eva y Autómata ponen a debate temas éticos y antropológicos desde diferentes prismas acerca de la ética en la robótica y la alteridad, lo que permite avivar el debate sobre la capacidad de sentir de robots y androides frente al imaginario colectivo.

La evolución del marketing social y la creciente demanda de los consumidores acerca de una mayor implicación de las marcas con causas sociales ha hecho potencialmente necesaria la comunicación de la RSE. Sin embargo, es debatible la eficacia de invertir en comunicación en medios pagados o si, por el contrario, es más rentable construir una narrativa de marca en medios propios y ganados mediante la creación de contenido, la experiencia de usuario o la marca personal de sus fundadores, entre otras estrategias. En este sentido, mediante un análisis cualitativo comparativo e interdisciplinar, esta investigación pretende analizar y determinar qué elementos estimulan la construcción y expansión de la narrativa de marca mediante dos casos contrastados de empresas que trabajan con colectivos vulnerables y que han conseguido diferenciarse en sus sectores mediante la incorporación de la diversidad como un valor añadido: el proyecto socioempresarial La Fageda y el proyecto transformador La Casa de Carlota. A partir de la generalización analítica, se ha podido relacionar los resultados de este estudio con otros casos similares, con el objetivo de establecer unas pautas comunes generalizadas que puedan llegar a constituir una base teórica de aplicación para aquellas empresas o instituciones que quieran comunicar la RSE construyendo y potenciando su narrativa de marca mediante medios no pagados.

Resistance against antimicrobial peptides (AMPs) is often mediated by detoxification modules that rely on sensing the AMP through a BceAB-like ATP-binding cassette (ABC) transporter that subsequently activates a cognate two-component system (TCS) to mount the cell response. Here, the Lactococcus lactis ABC transporter YsaDCB is shown to constitute, together with TCS-G, a detoxification module that protects L. lactis against bacitracin and the bacteriocin Lcn972, both AMPs that inhibit cell wall biosynthesis. Initially, increased expression of ysaDCB was detected by RT-qPCR in three L. lactis resistant to Lcn972, two of which were also resistant to bacitracin. These mutants shared, among others, single-point mutations in ysaB coding for the putative Bce-like permease. These results led us to investigate the function of YsaDCB ABC-transporter and study the impact of these mutations. Expression in trans of ysaDCB in L. lactis NZ9000, a strain that lacks a functional detoxification module, enhanced resistance to both AMPs, demonstrating its role as a resistance factor in L. lactis. When the three different ysaB alleles from the mutants were expressed, all of them outperformed the wild-type transporter in resistance against Lcn972 but not against bacitracin, suggesting a distinct mode of protection against each AMP. Moreover, PysaD promoter fusions, designed to measure the activation of the detoxification module, revealed that the ysaB mutations unlock transcriptional control by TCS-G, resulting in constitutive expression of the ysaDCB operon. Finally, deletion of ysaD was also performed to get an insight into the function of this gene. ysaD encodes a secreted peptide and is part of the ysaDCB operon. YsaD appears to modulate signal relay between the ABC transporter and TCS-G, based on the different response of the PysaD promoter fusions when it is not present. Altogether, the results underscore the unique features of this lactococcal detoxification module that warrant further research to advance in our overall understanding of these important resistance factors in bacteria.

This paper reports on the polymorphism of 2-propyl-1H-benzimidazole (2PrBzIm) induced by temperature change. Upon heating, an irreversible reconstructive-type phase transition at T = 384 K from the ordered form I (P212121) to a new polymorph, form IIHT (Pcam), was observed. The structural transformation between forms I and II involves significant changes in the crystal packing, as well as a key conformational variation around the propyl chain of the molecule. After the first irreversible phase transition, the IIHT form undergoes two further (reversible) phase transitions upon cooling at 361 K (IIRT) and 181 K (IILT). All three phases (forms IIHT, IIRT and IILT) have almost identical crystal packing and, given the reversibility of the conversions as a function of temperature, they are referred to as form II temperature phases. They differ, however, with respect to conformational variations around the propyl chain of 2PrBzIm. Energy calculations of the gas-phase conformational energy landscape of this compound about its flexible bonds allowed us to classify the observed conformational variations of all forms into changes and adjustments of conformers. This reveals that forms I and II are related by conformational change, and that two of the form II phases (HT and RT) are related by conformational adjustment, whilst the other two (RT and LT) are related by conformational change. We introduce the term `conformational phases' for different crystal phases with almost identical packing but showing changes in conformation.

Abstract Background Lactococcus lactis is the main component of the mesophilic starters used in cheese manufacture. The success of milk fermentation relies on the viability and metabolic activity of the starter bacteria. Therefore, robust strains able to withstand the harsh conditions encountered during cheese manufacture and starter production are demanded. In this work, we have applied adaptive evolution under cell envelope stress imposed by the cell wall active bacteriocin Lcn972 to evolve strains with more robust phenotypes. Results Consecutive exposure of the starter strain L. lactis IPLA947 to Lcn972 yielded a stable mutant, L. lactis R5, with enhanced survival when challenged with hydrogen peroxide. L. lactis R5 exhibited faster growth rates in aerobic fermentations in broth and was able to acidify milk to a lower pH in aerated milk cultures. The improved behavior of L. lactis R5 in the presence of oxygen did not translate into a better performance in the presence of heme (i.e. respiration metabolism) or into higher survival during storage at cold temperatures or after freeze-drying compared to the wild type L. lactis IPLA947. L. lactis R5 retained the same milk acidification rate and no changes in the consumption of lactose and production of organic acids were noticed. However, the profile of volatile compounds revealed a significant increase in 3-hydroxy-2-butanone (acetoin) in curds manufactured with L. lactis R5. Conclusions Based on our results, L. lactis R5 can be proposed as a suitable dairy starter with improved survival under oxidative stress and enhanced metabolic traits. The results support the notion that adaptive evolution under cell envelope stress might be useful to generate strain diversity within industrial L. lactis strains.

Lactococcus lactis is widely used as a starter in the manufacture of cheese and fermented milk. Its main role is the production of lactic acid, but also contributes to the sensory attributes of cheese. Unfortunately, the diversity of suitable strains to be commercialized as dairy starters is limited. In this work, we have applied adaptive evolution under cell envelope stress (AE-CES) as means to provide evolved L. lactis strains with distinct physiological and metabolic traits. A total of seven strains, three of industrial origin and four wild nisin Z-producing L. lactis, were exposed to subinhibitory concentrations of Lcn972, a bacteriocin that triggers the cell envelope stress response in L. lactis. Stable Lcn972 resistant (Lcn972R) mutants were obtained from all of them and two mutants per strain were further characterized. Minimal inhibitory Lcn972 concentrations increased from 4- to 32-fold compared to their parental strains and the Lcn972R mutants retained similar growth parameters in broth. All the mutants acidified milk to a pH below 5.3 with the exception of one that lost the lactose plasmid during adaptation and was unable to grow in milk, and two others with slower acidification rates in milk. While in general phage susceptibility was unaltered, six mutants derived from three nisin Z producers became more sensitive to phage attack. Loss of a putative plasmid-encoded anti-phage mechanism appeared to be the reason for phage susceptibility. Otherwise, nisin production in milk was not compromised. Different inter- and intra-strain-dependent phenotypes were observed encompassing changes in cell surface hydrophobicity and in their autolytic profile with Lcn972R mutants being, generally, less autolytic. Resistance to other antimicrobials revealed cross-protection mainly to cell wall-active antimicrobials such as lysozyme, bacitracin, and vancomycin. Finally, distinct and shared non-synonymous mutations were detected in the draft genome of the Lcn972R mutants. Depending on the parental strain, mutations were found in genes involved in stress response, detoxification modules, cell envelope biogenesis and/or nucleotide metabolism. As a whole, the results emphasize the different strategies by which each strain becomes resistant to Lcn972 and supports the feasibility of AE-CES as a novel platform to introduce diversity within industrial L. lactis dairy starters.

The mechanism of the base catalyzed hydrolysis of tetramethoxysilane (TMOS), proposed earlier on the basis of experimental data, is assessed by theoretical methods, i.e.MP2 and B3LYP with 6-31G(d) and Dunning correlation-consistent basis sets. Models considered involve one and two hydrolyzing water molecules attacking (MeO)4Si in the frontside position with a nucleophile (NH3and OH−) in the backside position. This approach allowed us to simulate uniformly the catalytic action of weak and strong bases. It was shown that the presence of a base in the backside position considerably lowers the activation barrier for hydrolysis. The inclusion of the additional water molecule which results in a substantial lowering of the barrier for uncatalyzed hydrolysis does not change noticeably the catalytic effect. In both one- and two-water molecules models the structure of the transition state in the presence of a nucleophile becomes nearly octahedral in which hexacoordinate silicon and four oxygens of the TMOS moiety have a planar arrangement [ABSTRACT FROM AUTHOR]