Superconformal Block Quivers, Duality Trees and Diophantine Equations

We generalize previous results on N = 1, (3 + 1)-dimensional superconformal block quiver gauge theories. It is known that the necessary conditions for a theory to be superconformal, i.e. that the beta and gamma functions vanish in addition to anomaly cancellation, translate to a Diophantine equation in terms of the quiver data. We re-derive results for low block numbers revealing an new intriguing algebraic structure underlying a class of possible superconformal fixed points of such theories. After explicitly computing the five block case Diophantine equation, we use this structure to reorganize the result in a form that can be applied to arbitrary block numbers. We argue that these theories can be thought of as vectors in the root system of the corresponding quiver and superconformality conditions are shown to associate them to certain subsets of imaginary roots. These methods also allow for an interpretation of Seiberg duality as the action of the affine Weyl group on the root lattice

Mineralogical evolution of cement pastes at early ages based on thermogravimetric analysis (TGA)

[EN] Ordinary thermogravimetric analysis (TG) and high-resolution TG tests were carried out on three different Portland cement pastes to study the phases present during the first day of hydration. Tests were run at 1, 6, 12 and 24 h of hydration, in order to determine the phases at these ages. High-resolution TG tests were used to separate decompositions presented in the 100¿200 C interval. The non-evaporable water determined by TG was used to determine hydration degree for the different ages. The effect of particle size distribution (PSD) on mineralogical evolution was established, as well as the addition of calcite as mineralogical filler. Finer PSD and calcite addition accelerate the hydration process, increasing the hydration degree on the first day of eaction between water and cement. According to high-resolution TG results, it was demonstrated that ettringite was the only decomposed phase in the 100¿200 C interval during the first 6 h of hydration for all studied cements. C-S-H phase starts to appear in all cements after 12 h of hydration.Funding was provided by Colciencias (Grant No. Convocatoria 567-2012).Gaviria, X.; Borrachero Rosado, MV.; Paya Bernabeu, JJ.; Monzó Balbuena, JM.; Tobón, J. (2018). Mineralogical evolution of cement pastes at early ages based on thermogravimetric analysis (TGA). Journal of Thermal Analysis and Calorimetry. 132(1):39-46. https://doi.org/10.1007/s10973-017-6905-0S39461321Benboudjema F, Meftah JM, Torernti F. Interaction between drying, shrinkage, creep and cracking phenomena in concrete. Eng Struct. 2005;27:239–50.Holt E. Contribution of mixture design to chemical and autogenous shrinkage of concrete at early ages. Cem Concr Res. 2005;35:464–72.Darquennes A, Staquet S, Delplancke-Ogletree MP, Espion B. Effect of autogenous deformation on the cracking risk of slag cement concretes. Cem Concr Compos. 2011;33:368–79.Slowik V, Schmidt M, Fritzsch R. 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Pathways of cellular internalisation of liposomes delivered siRNA and effects on siRNA engagement with target mRNA and silencing in cancer cells

Design of an efficient delivery system is a generally recognised bottleneck in translation of siRNA technology into clinic. Despite research efforts, cellular processes that determine efficiency of siRNA silencing achieved by different delivery formulations remain unclear. Here, we investigated the mechanism(s) of cellular internalisation of a model siRNA-loaded liposome system in a correlation to the engagement of delivered siRNA with its target and consequent silencing by adopting siRNA molecular beacon technology. Probing of cellular internalisation pathways by a panel of pharmacological inhibitors indicated that clathrin-mediated (dynamin-dependent) endocytosis, macropinocytosis (dynamine independent), and cell membrane cholesterol dependent process(es) (clathrin and caveolea-independent) all play a role in the siRNA-liposomes internalization. The inhibition of either of these entry routes was, in general, mirrored by a reduction in the level of siRNA engagement with its target mRNA, as well as in a reduction of the target gene silencing. A dramatic increase in siRNA engagement with its target RNA was observed on disruption of endosomal membrane (by chloroquine), accompanied with an increased silencing. The work thus illustrates that employing molecular beacon siRNA technology one can start to assess the target RNA engagement – a stage between initial cellular internalization and final gene silencing of siRNA delivery systems

Ebola: translational science considerations

We are currently in the midst of the most aggressive and fulminating outbreak of Ebola-related disease, commonly referred to as “Ebola”, ever recorded. In less than a year, the Ebola virus (EBOV, Zaire ebolavirus species) has infected over 10,000 people, indiscriminately of gender or age, with a fatality rate of about 50%. Whereas at its onset this Ebola outbreak was limited to three countries in West Africa (Guinea, where it was first reported in late March 2014, Liberia, where it has been most rampant in its capital city, Monrovia and other metropolitan cities, and Sierra Leone), cases were later reported in Nigeria, Mali and Senegal, as well as in Western Europe (i.e., Madrid, Spain) and the US (i.e., Dallas, Texas; New York City) by late October 2014. World and US health agencies declared that the current Ebola virus disease (EVD) outbreak has a strong likelihood of growing exponentially across the world before an effective vaccine, treatment or cure can be developed, tested, validated and distributed widely. In the meantime, the spread of the disease may rapidly evolve from an epidemics to a full-blown pandemic. The scientific and healthcare communities actively research and define an emerging kaleidoscope of knowledge about critical translational research parameters, including the virology of EBOV, the molecular biomarkers of the pathological manifestations of EVD, putative central nervous system involvement in EVD, and the cellular immune surveillance to EBOV, patient-centered anthropological and societal parameters of EVD, as well as translational effectiveness about novel putative patient-targeted vaccine and pharmaceutical interventions, which hold strong promise, if not hope, to curb this and future Ebola outbreaks. This work reviews and discusses the principal known facts about EBOV and EVD, and certain among the most interesting ongoing or future avenues of research in the field, including vaccination programs for the wild animal vectors of the virus and the disease from global translational science perspective