Shintani descent for standard supercharacters of algebra groups

Let $\mathcal{A}(q)$ be a finite-dimensional nilpotent algebra over a finite field $\mathbb{F}_{q}$ with $q$ elements, and let $G(q) = 1+\mathcal{A}(q)$. On the other hand, let $\Bbbk$ denote the algebraic closure of $\mathbb{F}_{q}$, and let $\mathcal{A} = \mathcal{A}(q) \otimes_{\mathbb{F}_{q}} \Bbbk$. Then $G = 1+\mathcal{A}$ is an algebraic group over $\Bbbk$ equipped with an $\mathbb{F}_{q}$-rational structure given by the usual Frobenius map $F:G\to G$, and $G(q)$ can be regarded as the fixed point subgroup $G^{F}$. For every $n \in \mathbb{N}$, the $n$th power $F^{n}:G\to G$ is also a Frobenius map, and $G^{F^{n}}$ identifies with $G(q^{n}) = 1 + \mathcal{A}(q^{n})$. The Frobenius map restricts to a group automorphism $F:G(q^{n})\to G(q^{n})$, and hence it acts on the set of irreducible characters of $G(q^{n})$. Shintani descent provides a method to compare $F$-invariant irreducible characters of $G(q^{n})$ and irreducible characters of $G(q)$. In this paper, we show that it also provides a uniform way of studying supercharacters of $G(q^{n})$ for $n \in \mathbb{N}$. These groups form an inductive system with respect to the inclusion maps $G(q^{m}) \to G(q^{n})$ whenever $m \mid n$, and this fact allows us to study all supercharacter theories simultaneously, to establish connections between them, and to relate them to the algebraic group $G$. Indeed, we show that Shintani descent permits the definition of a certain ``superdual algebra'' which encodes information about the supercharacters of $G(q^{n})$ for $n \in \mathbb{N}$

Theoretical study of the influence of salt doping in the functioning of OLEDs

One of the strategies to improve the efficiency of organic light emitting diodes (OLEDs) is to dope the active organic semiconducting layer with inorganic salts, leading to the development of a hybrid organic/inorganic hetero-structure. However, it is hard to know from the experiments how each one of the electronic processes underlying the functioning of OLEDs are affected by the accumulation of inorganic ions of different sign at both organic/electrode interfaces. In order to assess these effects, we performed computer simulations by using a multi-scale model that combines quantum molecular dynamics calculations at atomistic scale with Monte Carlo calculations at mesoscopic scale. We focus our attention on the main differences obtained between doped and pristine organic layers, when bipolar charge injection occurs. Our results show a significant drop on the turn-on applied electric field while maintaining rapid response to the applied field as well as a clear increase in recombination rate and recombination efficiency far from the electrodes for the doped situation, which are responsible for the dramatic improvement of doped OLED performance found in the experiments.Fundação para a Ciência e a Tecnologia (FCT) – Programa Operacional “Ciência , Tecnologia, Inovação” – CONC-REEQ/443/EEI/2005, SFRH/BD/62536/200

The effect of the interproximal creeping attachment in aesthetic site after root coverage surgery with VISTA technique - a case report

Gingival recession is a common manifestation in most populations. The mechanism by which gingival recession occurs is not well understood, but it seems to be complex and multifactorial. The main etiological factors are the accumulation of dental plaque biofilm with the resulting inflammatory periodontal diseases and mechanical trauma due to faulty oral hygiene techniques, especially in thin biotypes. This case report describes the treatment of a vestibular recession associated with interdental bone loss, with the VISTA technique associated with a connective tissue graft. The case was evaluated at 3, 9 months and 48 months after the surgery clinically complete root coverage and increased thickness of keratinized tissue were achieved, and the interdental papilla was augmented improving the soft tissue quality for future orthodontic treatment. VISTA technique associated with a connective tissue graft to reconstruct vertically papilla is a promising alternative for minimally invasive treatment and stable after 4 years.info:eu-repo/semantics/publishedVersio

Performance of adobe vaults strengthened with LC-TRM: an experimental approach

Due to the vulnerability of vaulted adobe buildings during the past earthquakes, it is crucial for such building typology to be evaluated in terms of seismic capacity. This paper deals with the seismic performance of historic vaulted adobe construction in adobe houses, typical from the city of Yazd, Iran. To this end, six 1:3 scaled adobe vaults were analyzed experimentally aiming at estimating their structural performance. The tests were performed in loading-unloading steps of increasing amplitude of an imposed vertical displacement at 30% of span. The tests were carried out in two unstrengthened and four strengthened adobe vaults. Vaults were strengthened with a low cost textile reinforced mortar (LC-TRM), where a low cost fiber-glass mesh is covered with an earth-based mortar. Two adobe vaults were strengthened at intrados and the other two at extrados. The experimental results show that the vaults behavior is enhanced due to the LC-TRM application, with respect to the unstrengthened vaults. A significant increase of the load carrying capacity and also an important improvement in ductility was evident. In addition, new failure mechanisms were observed for the strengthened vaults when compared with the formation of the typical four-hinge mechanism of unstrengthened vaults.FEDER funds through the Competitivity Factors Operational Program - COMPETE and by national funds through FCT – Foundation for Science and Technology within the scope of projects POCI-01-0145-FEDER-007633 and POCI-01-0145-FEDER-016737 (PTDC/ECM-EST/2777/2014

Development of bio-hybrid piezoresistive nanocomposites using silk-elastin protein copolymers

Recombinant silk-elastin-like protein (SELP)/carbon nanotubes (CNTs) nanocomposite films with different amounts of CNTs (1, 3 and 6wt%) were prepared by solvent casting. The produced films were stabilized by exposure to methanol that induces an increase of the -structure content. The CNTs were homogeneously distributed into the SELP matrix and did not induce significant alterations into its chemical structure. The incorporation of CNTs also increased the thermal stability of the films. Further, the incorporation of 1wt% of CNTs greatly improved the mechanical properties of the SELP matrix leading to a 6-fold increase in strain-to-failure and to increase the ultimate tensile strength with minor differences in modulus of elasticity. The nanocomposites exhibited a good linearity between deformation and electrical resistance variation with electrical conductivity increasing with the nanofiller content up to 0.8Sm1. Finally, the produced nanocomposites were non-cytotoxic indicating their suitability for biomedical applications.This work was supported by national funds through FCT I.P. (Fundação para a Ciência e Tecnologia, Portugal) and by the European Regional Development Fund (ERDF) through COMPETE2020 Programa Operacional Competitividade e Internacionalização (POCI, Portugal) in the framework of the Strategic Programs UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) and UID/FIS/04650/2013. This work was also supported by the strategic programme UID/BIA/04050/2019 funded by national funds through FCT I.P. The present work was also supported by FCT I.P. within the ERA-NET IB-2 project FunBioPlas (ERA-IB-2-6/0004/2014), EuroNanoMed 2016 call and project LungChek ENMed/0049/2016. DMC, SR and CR also thank FCT I.P. for the grants SFRH/BPD/121526/2016, SFRH/BD/111478/2015, and SFRH/BPD/90870/2012, respectively. This article is a result of the project EcoAgriFood [NORTE-01-0145-FEDER-000009], supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). Finally, the authors acknowledge funding by the Spanish Ministry of Economy and Competitiveness (MINECO) through the project MAT2016-76039-C4-3-R (AEI/FEDER, UE) and from the Basque Government Industry Department under the ELKARTEK and HAZITEK programs.info:eu-repo/semantics/publishedVersio

Structural and functional analysis of mRNA export regulation by the nuclear pore complex

The nuclear pore complex (NPC) controls the passage of macromolecules between the nucleus and cytoplasm, but how the NPC directly participates in macromolecular transport remains poorly understood. In the final step of mRNA export, the DEAD-box helicase DDX19 is activated by the nucleoporins Gle1, Nup214, and Nup42 to remove Nxf1•Nxt1 from mRNAs. Here, we report crystal structures of Gle1•Nup42 from three organisms that reveal an evolutionarily conserved binding mode. Biochemical reconstitution of the DDX19 ATPase cycle establishes that human DDX19 activation does not require IP_6, unlike its fungal homologs, and that Gle1 stability affects DDX19 activation. Mutations linked to motor neuron diseases cause decreased Gle1 thermostability, implicating nucleoporin misfolding as a disease determinant. Crystal structures of human Gle1•Nup42•DDX19 reveal the structural rearrangements in DDX19 from an auto-inhibited to an RNA-binding competent state. Together, our results provide the foundation for further mechanistic analyses of mRNA export in humans