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The rotational spectra of the 1:1 complex formed by acrolein and methanol and its deuterated isotopologues have been analyzed. Two stable conformations in which two hydrogen bonds between the two moieties are formed were detected. The rotational lines show a hyperfine structure due to the methyl group internal rotation in the complex and the V3 barriers hindering the motion were determined as 2.629(5) kJ mol−1 and 2.722(5) kJ mol−1 for the two conformations, respectively. Quantum mechanical calculations at the MP2/aug-cc-pVTZ level and comprehensive analysis of the intermolecular interactions, utilizing NCI and SAPT approaches, highlight the driving forces of the interactions and allow the determination of the binding energies of complex formation.

El libro que el editor ha preparado para la publicación se basa en dos manuscritos que fueron dejados por Coseriu como parte de su legado intelectual, los cuales le sirvieron para sus cursos en la Universidad de Tubinga en los años ’70 del siglo pasado. La primera parte trata de la fonología clásica de Praga, de sus inicios, su desarrollo como modelo del estructuralismo así como sus fundamentos teóricos. Un objetivo que le importa a Coseriu es la discusión crítica de ciertas suposiciones teóricas de Trubetzkoy. Coseriu transciende el estructuralismo al desarrollar algunas bases de una lingüística del hablar orientada hacia la competencia del hablante. En la segunda parte, “Romanische Phonologie”, se presenta una combinación de descripciones fonológicas y fonéticas del italiano, español y francés. Se discuten los que Coseriu llama los “puntos débiles” de los sistemas fonológicos de estas tres lenguas, los que son oposiciones caracterizadas por un rendimiento funcional débil, y se exploran las consecuencias de esta situación para la pronunciación normativa de las variantes fijas, establecidas. Esto concierne sobre todo la lengua más complicada en este sentido, el francés, pero también el italiano. La comparación de los sistemas fonológicos de las tres lenguas termina la obra.

Mesenchymal stem cells (MSCs) are primary candidates in tissue engineering and stem cell therapies due to their intriguing regenerative and immunomodulatory potential. Their ability to self-assemble into three-dimensional (3D) aggregates further improves some of their therapeutic properties, e.g., differentiation potential, secretion of cytokines, and homing capacity after administration. However, high hydrodynamic shear forces and the resulting mechanical stresses within commercially available dynamic cultivation systems can decrease their regenerative properties. Cells embedded within a polymer matrix, however, lack cell-to-cell interactions found in their physiological environment. Here, we present a “semi scaffold-free” approach to protect the cells from high shear forces by a physical barrier, but still allow formation of a 3D structure with in vivo-like cell-to-cell contacts. We highlight a relatively simple method to create core–shell capsules by inverse gelation. The capsules consist of an outer barrier made from sodium alginate, which allows for nutrient and waste diffusion and an inner compartment for direct cell-cell interactions. Next to capsule characterization, a harvesting procedure was established and viability and proliferation of human adipose-derived MSCs were investigated. In the future, this encapsulation and cultivation technique might be used for MSC-expansion in scalable dynamic bioreactor systems, facilitating downstream procedures, such as cell harvest and differentiation into mature tissue grafts.

The use of 3D cell cultures has gained increasing importance in medical and pharmaceutical research. However, the analysis of the culture medium is hardly representative for the culture conditions within a 3D model which hinders the standardization of 3D cultures and translation of results. Therefore, we developed a modular monitoring platform combining a perfusion bioreactor with an integrated minimally invasive sampling system and implemented sensors that enables the online monitoring of culture parameters and medium compounds within 3D cultures. As a proof-of-concept, primary cells as well as cell lines were cultured on a collagen or gelatin methacryloyl (GelMA) hydrogel matrix, while monitoring relevant culture parameters and analytes. Comparing the interstitial fluid of the 3D models versus the corresponding culture medium, we found considerable differences in the concentrations of several analytes. These results clearly demonstrate that analyses of the culture medium only are not relevant for the development of standardized 3D culture processes. The presented bioreactor with an integrated sampling and sensor platform opens new horizons for the development, optimization, and standardization of 3D cultures. Furthermore, this technology holds the potential to reduce animal studies and improve the transferability of pharmaceutical in vitro studies by gaining more relevant results, bridging the gap towards clinical translation.

The Mec1/ATR kinase is crucial for genome stability, yet the mechanism by which it prevents gross chromosomal rearrangements (GCRs) remains unknown. Here we find that in cells with deficient Mec1 signaling, GCRs accumulate due to the deregulation of multiple steps in homologous recombination (HR). Mec1 primarily suppresses GCRs through its role in activating the canonical checkpoint kinase Rad53, which ensures the proper control of DNA end resection. Upon loss of Rad53 signaling and resection control, Mec1 becomes hyperactivated and triggers a salvage pathway in which the Sgs1 helicase is recruited to sites of DNA lesions via the 911-Dpb11 scaffolds and phosphorylated by Mec1 to favor heteroduplex rejection and limit HR-driven GCR accumulation. Fusing an ssDNA recognition domain to Sgs1 bypasses the requirement of Mec1 signaling for GCR suppression and nearly eliminates D-loop formation, thus preventing non-allelic recombination events. We propose that Mec1 regulates multiple steps of HR to prevent GCRs while ensuring balanced HR usage when needed for promoting tolerance to replication stress.

Se describe la sintaxis pronominal según la jerarquía de las personas que existe en las lenguas de la gran familia Mawetí-Guaraní. El enfoque nuevo resulta de la interpretación de las formas mismas que se usan en la sintaxis pronominal: Cuando se trata de 1,2,3 > 3 observamos la sintaxis normal, es decir que el verbo transitivo recibe el prefijo personal de los verbos activos y el objeto pronominal aparece después del verbo si es un objeto animado; el objeto pronominal inanimado se omite. Sin embargo, cuando se trata de 3 > 1,2 o 2 > 1, la sintaxis cambia radicalmente, omitiéndose la marca personal sujeto del verbo transitivo. Lo que en inglés es el pronombre de objeto (por ejemplo, en "she saw me" o "you called me"), aparece en Mawetí-Guaraní delante del verbo, en forma de pronombre personal (o de marca personal/posesiva de los nombres). Yo interpreto esta mudanza como un cambio de verbo activo con objeto a una construcción existencial: en lugar de decir "ella me vio", la mayoría de las lenguas mawetí-guaraníes dice "hubo vista mía por parte de ella". En mbyá, por ejemplo: a'e xer-exa 3.PRON 1SG.N REL-ver/vista Este ejemplo es especialmente significativo porque contiene la construcción típicamente nominal con el elemento REL de la flexión relacional tan característica de estas lenguas. Debido a la distinción difusa entre radicales verbales y radicales nominales en mawetí-guaraní, el cambio ("switching") de una clase de palabras a la otra es fácil.

Gasdermins (GSDMs) share a common functional domain structure and are best known for their capacity to form membrane pores. These pores are hallmarks of a specific form of cell death called pyroptosis and mediate the secretion of pro-inflammatory cytokines such as interleukin 1β (IL1β) and interleukin 18 (IL18). Thereby, Gasdermins have been implicated in various immune responses against cancer and infectious diseases such as acute Salmonella Typhimurium (S.Tm) gut infection. However, to date, we lack a comprehensive functional assessment of the different Gasdermins (GSDMA-E) during S.Tm infection in vivo. Here, we used epithelium-specific ablation, bone marrow chimeras, and mouse lines lacking individual Gasdermins, combinations of Gasdermins or even all Gasdermins (GSDMA1-3C1-4DE) at once and performed littermate-controlled oral S.Tm infections in streptomycin-pretreated mice to investigate the impact of all murine Gasdermins. While GSDMA, C, and E appear dispensable, we show that GSDMD i) restricts S.Tm loads in the gut tissue and systemic organs, ii) controls gut inflammation kinetics, and iii) prevents epithelium disruption by 72 h of the infection. Full protection requires GSDMD expression by both bone-marrow-derived lamina propria cells and intestinal epithelial cells (IECs). In vivo experiments as well as 3D-, 2D-, and chimeric enteroid infections further show that infected IEC extrusion proceeds also without GSDMD, but that GSDMD controls the permeabilization and morphology of the extruding IECs, affects extrusion kinetics, and promotes overall mucosal barrier capacity. As such, this work identifies a unique multipronged role of GSDMD among the Gasdermins for mucosal tissue defense against a common enteric pathogen.

Neste estudo, se descrevem, em todas as línguas do tronco tupi acessíveis, com a inclusão da família Tupi-Guarani, as diferentes funções de negação nas orações declarativas e existenciais, nos predicados nominalizados, nas proibitivas e na negação de constituintes. Analisam-se estas funções de negação numa tipologia que considera o número de funções negativas e numa segunda tipologia que se estabelece com respeito à coesão morfológica das expressões negativas. Esta pode ser maior (morfologia sintética) ou menor (morfologia analítica). Resulta que as línguas Tupi-Guarani, na sua maioria, desenvolveram um maior grau de síntese do que membros das outras famílias Tupi.

Hoje conhecemos dez dicionários de língua geral amazônica, seis deles não publicados. Em comparação, a língua geral paulista continua pouco documentada. Estudam-se seis dicionários de língua geral amazônica setecentistas, em especial três manuscritos ainda não publicados. Da comparação desses dicionários, resulta a identificação de Anselm Eckart como autor de um e de Anton Meisterburg como possível autor de outro manuscrito. Analisa-se a interdependência de Eckart, Meisterburg e da "Prosodia de Lingua". Descrevem-se mudanças ocorridas na LGA e discutem-se caraterísticas da LGP. Tudo isto serve para rever os problemas téoricos do conceito de "língua geral" proposto por Aryon Rodrigues e problemas da história da sua formação.

Punctuated bursts of structural genomic variations (SVs) have been described in various organisms, but their etiology remains incompletely understood. Homologous recombination (HR) is a template-guided mechanism of repair of DNA double-strand breaks and stalled or collapsed replication forks. We recently identified a DNA break amplification and genome rearrangement pathway originating from the endonucleolytic processing of a multi-invasion (MI) DNA joint molecule formed during HR. Genome-wide approaches confirmed that multi-invasion-induced rearrangement (MIR) frequently leads to several repeat-mediated SVs and aneuploidies. Using molecular and genetic analysis and a novel, highly sensitive proximity ligation-based assay for chromosomal rearrangement quantification, we further delineate two MIR subpathways. MIR1 is a universal pathway occurring in any sequence context, which generates secondary breaks and frequently leads to additional SVs. MIR2 occurs only if recombining donors exhibit substantial homology and results in sequence insertion without additional breaks or SVs. The most detrimental MIR1 pathway occurs late on a subset of persisting DNA joint molecules in a PCNA/Polδ-independent manner, unlike recombinational DNA synthesis. This work provides a refined mechanistic understanding of these HR-based SV formation pathways and shows that complex repeat-mediated SVs can occur without displacement DNA synthesis. Sequence signatures for inferring MIR1 from long-read data are proposed.

Saccharomyces cerevisiae DNA polymerase IV (Pol4) like its homolog, human DNA polymerase lambda (Polλ), is involved in Non-Homologous End-Joining and Microhomology-Mediated Repair. Using genetic analysis, we identified an additional role of Pol4 also in homology-directed DNA repair, specifically in Rad52-dependent/Rad51-independent direct-repeat recombination. Our results reveal that the requirement for Pol4 in repeat recombination was suppressed by the absence of Rad51, suggesting that Pol4 counteracts the Rad51 inhibition of Rad52-mediated repeat recombination events. Using purified proteins and model substrates, we reconstituted in vitro reactions emulating DNA synthesis during direct-repeat recombination and show that Rad51 directly inhibits Polδ DNA synthesis. Interestingly, although Pol4 was not capable of performing extensive DNA synthesis by itself, it aided Polδ in overcoming the DNA synthesis inhibition by Rad51. In addition, Pol4 dependency and stimulation of Polδ DNA synthesis in the presence of Rad51 occurred in reactions containing Rad52 and RPA where DNA strand-annealing was necessary. Mechanistically, yeast Pol4 displaces Rad51 from ssDNA independent of DNA synthesis. Together our in vitro and in vivo data suggest that Rad51 suppresses Rad52-dependent/Rad51-independent direct-repeat recombination by binding to the primer-template and that Rad51 removal by Pol4 is critical for strand-annealing dependent DNA synthesis.

Chronic obstructive lung disease determines morbidity and mortality of patients with cystic fibrosis (CF). CF airways are characterized by a nonresolving neutrophilic inflammation. After pathogen contact or prolonged activation, neutrophils release DNA fibres decorated with antimicrobial proteins, forming neutrophil extracellular traps (NETs). NETs have been described to act in a beneficial way for innate host defense by bactericidal, fungicidal, and virucidal actions. On the other hand, excessive NET formation has been linked to the pathogenesis of autoinflammatory and autoimmune disease conditions. We quantified free DNA structures characteristic of NETs in airway fluids of CF patients and a mouse model with CF-like lung disease. Free DNA levels correlated with airflow obstruction, fungal colonization, and CXC chemokine levels in CF patients and CF-like mice. When viewed in combination, our results demonstrate that neutrophilic inflammation in CF airways is associated with abundant free DNA characteristic for NETosis, and suggest that free DNA may be implicated in lung function decline in patients with CF.

Este artigo trata de uma interpretação das sociedades caribenhas na base dos conceitos de força e das culturas rizomáticas, utilizando um exemplo da Ilha de Santa Lúcia. Três dimensões foram apresentadas: a organização familiar extensa e flexível; a ampla variedade na tulização da terra e organização do trabalho; e a flexibilidade nas relações múltiplas que aparecem na discussão da filosofia ocidental pós-moderna e nos elementos das filosofias energéticas africanas do axé e ntu. Palavras-chave: Filosofia Caribenha Pós-colonial. Culturas Rizomáticas. Identidades Resumen Este artículo trata de una interpretmas basados en el ejemplo de la isla de Santa Lucía. Tres dimensiones han sido presentadas: la organización familiar extensa y flexible; la amplia variedad en la utilización de la tierra, la organización del trabajo y la flexibilidad en las relaciones multiples que aparcen en la discusión de la filosofía occidental post modernas y en los elementos y las filosofias energéticas africanas del aché y el ntu. Palabras claves: Filosofía Caribenha Post colonial. Culturas Rizomáticas. Identaidades Abstract This paper deals with na interpretation of the Caribbeas societies based on the concepts of force and rizomatic cultures, through an example from Santa Lucia Island. Three dimensions are presented: the flexible and extended familiar organization; the wide variety on the use of the land and the work organization; and the flexibility in the multiple relations that appear in the pos-modern occidental philosophic discussion and in the elements of the energetic African philosophics of axe and ntu. Keywords: Caribbean Pos-colonial Philosophy. Rhizomatic Cultures. Identities

Recruitment of neutrophils into and across the gut mucosa is a cardinal feature of intestinal inflammation in response to enteric infections. Previous work using the model pathogen Salmonella enterica serovar Typhimurium (S.Tm) established that invasion of intestinal epithelial cells by S.Tm leads to recruitment of neutrophils into the gut lumen, where they can reduce pathogen loads transiently. Notably, a fraction of the pathogen population can survive this defense, re-grow to high density, and continue triggering enteropathy. However, the functions of intraluminal neutrophils in the defense against enteric pathogens and their effects on preventing or aggravating epithelial damage are still not fully understood. Here, we address this question via neutrophil depletion in different mouse models of Salmonella colitis, which differ in their degree of enteropathy. In an antibiotic pretreated mouse model, neutrophil depletion by an anti-Ly6G antibody exacerbated epithelial damage. This could be linked to compromised neutrophil-mediated elimination and reduced physical blocking of the gut-luminal S.Tm population, such that the pathogen density remained high near the epithelial surface throughout the infection. Control infections with a ssaV mutant and gentamicin-mediated elimination of gut-luminal pathogens further supported that neutrophils are protecting the luminal surface of the gut epithelium. Neutrophil depletion in germ-free and gnotobiotic mice hinted that the microbiota can modulate the infection kinetics and ameliorate epithelium-disruptive enteropathy even in the absence of neutrophil-protection. Together, our data indicate that the well-known protective effect of the microbiota is augmented by intraluminal neutrophils. After antibiotic-mediated microbiota disruption, neutrophils are central for maintaining epithelial barrier integrity during acute Salmonella-induced gut inflammation, by limiting the sustained pathogen assault on the epithelium in a critical window of the infection.

A dilute suspension in annular shear flow under gravity was simulated using multi-particle collision dynamics (MPC) and compared to experimental data. The focus of the analysis is the local particle velocity and density distribution under the influence of the rotational and gravitational forces. The results are further supported by a deterministic approximation of a single-particle trajectory and OpenFOAM CFD estimations of the overcritical frequency range. Good qualitative agreement is observed for single-particle trajectories between the statistical mean of MPC simulations and the deterministic approximation. Wall contact and detachment however occur earlier in the MPC simulation, which can be explained by the inherent thermal noise of the method. The multi-particle system is investigated at the point of highest particle accumulation that is found at 2/3 of the particle revolution, starting from the top of the annular gap. The combination of shear flow and a slowly rotating volumetric force leads to strong local accumulation in this section that increases the particle volume fraction from overall 0.7% to 4.7% at the outer boundary. MPC simulations and experimental observations agree well in terms of particle distribution and a close to linear velocity profile in radial direction.

The interdependency of structure and mechanical features of a cohesive powder packing is on current scientific focus and far from being well understood. Although the Discrete Element Method provides a well applicable and widely used tool to model powder behavior, non-trivial contact mechanics of micron-sized particles demand a sophisticated contact model. Here, a direct comparison between experiment and simulation on a particle level offers a proper approach for model validation. However, the simulation of a full scale shear-tester experiment with micron-sized particles, and hence, validating this simulation remains a challenge. We address this task by down scaling the experimental setup: A fully functional micro shear-tester was developed and implemented into an X-ray tomography device in order to visualize the sample on a bulk and particle level within small bulk volumes of the order of a few micro liter under well-defined consolidation. Using spherical micron-sized particles (30 μm), shear tests with a particle number accessible for simulations can be performed. Moreover, particle level analysis allows for a direct comparison of experimental and numerical results, e.g., regarding structural evolution. In this talk, we focus on density inhomogeneity and shear induced heterogeneity during compaction and shear deformation.

Densification of (semi-)conducting particle agglomerates with the help of an electrical current is much faster and more energy efficient than traditional thermal sintering or powder compression. Therefore, this method becomes more and more common among experimentalists, engineers, and in industry. The mechanisms at work at the particle scale are highly complex because of the mutual feedback between current and pore structure. This paper extends previous modelling approaches in order to study mixtures of particles of two different materials. In addition to the delivery of Joule heat throughout the sample, especially in current bottlenecks, thermoelectric effects must be taken into account. They lead to segregation or spatial correlations in the particle arrangement. Various model extensions are possible and will be discussed.

We study the relaxation time of granular media in simple shear by means of DEM simulations (the methods being Molecular Dynamics as well as Contact Dynamics) in two and three dimensions with rough and with smooth frictional walls. While the system with rough walls behaves according to its steady state constitutive laws, the systems with smooth walls show a much stronger increase of the relaxation time with driving strength than to be expected. Employing a dynamic non-local rheology model[1] allows for a stronger increase but not sufficiently so.

Signo y Seña es la revista especializada del Instituto de Lingüística de la Facultad de Filosofía y Letras de la Universidad de Buenos Aires. Convoca y está destinada a investigadores del lenguaje formados y en formación tanto de la Argentina como del exterior. Es una publicación semestral electrónica y de libre acceso que tiene como objetivo fundamental promover el debate, el intercambio de ideas y la difusión de investigaciones recientes de todas las áreas de la lingüística. Signo y Seña incluye en cada número: una sección temática o monográfica a cargo de reconocidos especialistas en el área,una sección general de resultados investigaciones de todas las áreas de la Lingüística y una sección de reseñas y novedades referentes a la disciplina. En sus páginas se publican trabajos originales e inéditos evaluados con el sistema de pares externos doble ciego en español y en portugués.

Neste artigo descrevem-se os recursos que usam os falantes do Guarani paraguaio e do Guarani do Chaco (tradicionalmente Chiriguano) para expressar categorias como o tempo, o aspecto e a evidencialidade. Do estudo gramatical das duas línguas resulta uma intuição dupla: A primeira consiste na impossibilidade de reconhecer categorias claras com paradigmas bem gramaticalizados. Tanto o Guarani paraguaio como o do Chaco caracterizam-se pelo uso extenso de sufixos e partículas que, porém, não formam categorias bem estabelecidas, com oposições gramaticais claras. Pode ser também que a linguística não opere com as categorias adequadas para estas línguas. A segunda intuição refere-se ao fato que a temporalidade representa uma categoria muito menos importante do que é a evidencialidade. Embora as línguas descritas aqui sejam línguas geneticamente pouco distantes, a descrição paralela dos recursos gramaticais do verbo faz ver as diferenças que existem no uso e na função de muitos morfemas que parecem ser os mesmos nas duas línguas.