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Kdm1a is a histone demethylase linked to intellectual disability with essential roles during gastrulation and the terminal differentiation of specialized cell types, including neurons, that remains highly expressed in the adult brain. To explore Kdm1a’s function in adult neurons, we develop inducible and forebrain-restricted Kdm1a knockouts. By applying multi-omic transcriptome, epigenome and chromatin conformation data, combined with super-resolution microscopy, we find that Kdm1a elimination causes the neuronal activation of nonneuronal genes that are silenced by the polycomb repressor complex and interspersed with active genes. Functional assays demonstrate that the N-terminus of Kdm1a contains an intrinsically disordered region that is essential to segregate Kdm1a-repressed genes from the neighboring active chromatin environment. Finally, we show that the segregation of Kdm1a-target genes is weakened in neurons during natural aging, underscoring the role of Kdm1a safeguarding neuronal genome organization and gene silencing throughout life.

In this work, 1 eV Ga0.7In0.3As inverted metamorphic (IMM) solar cells were analyzed to achieve a deeper understanding of the mechanism limiting their improvement. For this purpose, high-resolution X-ray diffraction (HRXRD), transmission electron microscopy (TEM), high-resolution cross-sectional cathodoluminescence (CL), and transient in situ surface reflectance were carried out. Additionally, the photovoltaic responses of the complete devices were measured using the external quantum efficiency (EQE) and numerically simulated through Silvaco TCAD ATLAS. The combination of structural characterization of the semiconductor layers and measurements of the solar cell photovoltaic behavior, together with device modeling, allows us to conclude that the lifetime of the bulk minority carriers is the limiting factor influencing the PV response since the recombination at the interfaces (GaInP window-GaInAs emitter and GaInAs base-GaInP back surface field (BSF)) does not impact the carrier recombination due to the favorable alignment between the conduction and the valance bands. The advanced characterization using cross-sectional cathodoluminescence, together with transient in situ surface reflectance, allowed the rejection of the formation of traps related to the GaInAs growth conditions as being responsible for the decrement in the minority-carrier lifetime. Conversely, the TEM and HRXRD revealed that the presence of misfit dislocations in the GaInAs layer linked to strain relaxation, which were probably formed due to an excessive tensile strain in the virtual substrate or an incorrect combination of alloy compositions in the topmost layers, was the dominant factor influencing the GaInAs layer's quality. These results allow an understanding of the contributions of each characterization technique in the analysis of multi-junction solar cells.

Van der Waals chalcogenides and chalcohalides have the potential to become the next thin film PV breakthrough, owing to the earth-abundancy and non-toxicity of their components, and their stability, high absorption coefficient and quasi-1D structure, which leads to enhanced electrical anisotropic properties when the material is oriented in a specific crystalline direction. However, quasi-1D semiconductors beyond Sb2(S,Se)3, such as SbSeX chalcohalides, have been scarcely investigated for energy generation applications, and rarely synthesised by physical vapor deposition methodologies, despite holding the promise of widening the bandgap range (opening the door to tandem or semi-transparent devices), and showing enticing new properties such as ferroelectric behaviour and defect-tolerant nature. In this work, SbSeI and SbSeBr micro-columnar solar cells have been obtained for the first time by an innovative methodology based on the selective halogenation of Sb2Se3 thin films at pressure above 1 atm. It is shown that by increasing the annealing temperature and pressure, the height and density of the micro-columnar structures grows monotonically, resulting in SbSeI single-crystal columns up to 30 µm, and tuneable morphology. In addition, solar cell prototypes with substrate configuration have shown remarkable Voc values above 550 mV and 1.8 eV bandgap., Peer Reviewed, Postprint (published version)

This experience report addresses the scientific popularization strategies employed in activities developed by the CULTPOP – Research Laboratory in Pop Culture, Communication and Technologies, linked to CNPq and currently based in the Graduate Program of Universidade Paulista (UNIP). It presents an overview of science popularization strategies organized based on the specific dynamics of the group’s research, as well as the use of pop culture’s own languages as part of its methodological process. The exploratory and descriptive case study indicates that having a laboratory community of academic-fans of pop culture facilitates and expands the development of science popularization strategies., Este relato de experiências trata de estratégias de popularização científica das atividades do CULTPOP – Laboratório de Pesquisa em Cultura Pop, Comunicação e Tecnologias, vinculado ao CNPq e atualmente sediado no Programa de Pós-Graduação da Universidade Paulista (UNIP). Faz-se um panorama das estratégias de popularização da ciência organizado a partir das dinâmicas específicas das pesquisas do grupo, bem como das utilizações das próprias linguagens da cultura pop como parte do processo metodológico. A metodologia do artigo é exploratória e descritiva, com base em Estudo de Caso1. As observações iniciais indicam que a inserção do laboratório em uma comunidade de acadêmicos-fãs de cultura pop facilita e amplia o desenvolvimento de estratégias de popularização da ciência.

The preservation of The Great Mosque of Córdoba (Spain) as a carrier of Andalusian collective memory requires innovative approaches to assess and maintain its structural health. This research centers on two non-destructive methods: direct ultrasound testing and rebound hammer. Laboratory tests were performed on natural stone provided by the primary material supplier for the Mosque’s restoration and rehabilitation works. Non-destructive and destructive tests were carried out over 10 ashlars and 100 cubic and prismatic specimens, which were cut from the ashlars. Tests were conducted in multiple directions to investigate stone anisotropy. Destructive testing indicated isotropy, but ultrasound test results disagreed. Sensitivity analysis of specimen dimensions affected result dispersion, but not average properties.

The Mosque of Cordoba (Spain) is an emblem of the rich cultural heritage of Western Andalusia. This research focuses on the mechanical characterization of the natural stone used in the building. Determining its properties is crucial to understanding the structural behaviour of the entire building. An experimental campaign with various mechanical tests, such as density, compression, indirect tensile, and bending tests, was conducted on more than 100 cubic and prismatic specimens obtained from the main quarry that supplies material for the mosque’s restoration. The results indicated the stone’s isotropic behaviour for the studied properties. Further analysis established correlations between compressive strength (averaging 6 MPa) and other mechanical properties. This preliminary characterization provides valuable information for future in situ testing and more sophisticated lab techniques.