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Abstract The CYGNO experiment aims to build a large ( $$\mathcal {O}(10)$$ O ( 10 ) m $$^3$$ 3 ) directional detector for rare event searches, such as nuclear recoils (NRs) induced by dark matter (DM), such as weakly interactive massive particles (WIMPs). The detector concept comprises a time projection chamber (TPC), filled with a He:CF $$_4$$ 4 60/40 scintillating gas mixture at room temperature and atmospheric pressure, equipped with an amplification stage made of a stack of three gas electron multipliers (GEMs) which are coupled to an optical readout. The latter consists in scientific CMOS (sCMOS) cameras and photomultipliers tubes (PMTs). The maximisation of the light yield of the amplification stage plays a major role in the determination of the energy threshold of the experiment. In this paper, we simulate the effect of the addition of a strong electric field below the last GEM plane on the GEM field structure and we experimentally test it by means of a 10 $$\times $$ × 10 cm $$^2$$ 2 readout area prototype. The experimental measurements analyse stacks of different GEMs and helium concentrations in the gas mixture combined with this extra electric field, studying their performances in terms of light yield, energy resolution and intrinsic diffusion. It is found that the use of this additional electric field permits large light yield increases without degrading intrinsic characteristics of the amplification stage with respect to the regular use of GEMs.

The civic mobilisation welcoming Ukrainian refugees after Russia’s invasion in February 2022 has shown how housing is a social infrastructure based on care and solidarity. But it has also shown its discriminatory face. By drawing on our recent collaborative research in Leipzig and Riga and conceptual reflections from previous research, this paper elaborates on how practices of welcoming and housing refugees intertwine with state racism and everyday discrimination. It is grounded in two intersecting lines of inquiry. The first one focuses on migrant housing struggles in the context of increased financialisation, privatisation and austerity urbanism. The second expands on the intersection of race and discrimination with housing, asking how race and racial discrimination intersect and affect migrants, refugees, and asylum seekers’ access to and experiences with housing. The underlying argument is that while housing is the site where this type of discrimination becomes spatialised and visible (and thus can be challenged), there is still a missing discourse around discrimination in migration and housing policy.

Resumo Este artigo tem por objetivo apresentar e discutir os dados sobre o estudo das representações de zoomorfos nos sítios com registros rupestres do estado de São Paulo. Conhecido por pesquisas arqueológicas voltadas a sambaquis e a materiais líticos, o estado de São Paulo apresenta poucos trabalhos em temáticas sobre pinturas e gravuras rupestres. Nos últimos anos, porém, vem crescendo o número de descobertas e de estudos baseados em sítios nessa temática. Com o objetivo de identificar similaridades e diferenças gráficas entre as figuras com características zoomórficas, a presente pesquisa partiu da análise da técnica, temática e cenografia dos painéis rupestres dos 55 sítios identificados no estado. Os resultados destacam um pequeno quantitativo dessas representações, em cenários pintados e gravados, com apenas 22 figuras, destacadas em nove sítios. Estão morfologicamente identificadas como cervídeos, aves, répteis e crustáceos, caracterizando-se por realizações gráficas isoladas em painéis, dominantemente marcados por representações não figurativas. Os animais representados destacam-se pelo pouco dinamismo e pelo escasso detalhamento anatômico. As figuras possuem um caráter hermético marcado.

Prelinguistic babbling is a critical phase in infant language development and is best understood in temperate songbirds where it occurs primarily in males at reproductive maturity and is modulated by sex steroids. Parrots of both sexes are icons of tropical vocal plasticity, but vocal babbling is unreported in this group and whether the endocrine system is involved is unknown. Here we show that vocal babbling is widespread in a wild parrot population in Venezuela, ensues in both sexes during the nestling stage, occurs amidst a captive audience of mixed-aged siblings, and is modulated by corticosteroids. Spectrographic analysis and machine learning found phoneme diversity and combinatorial capacity increased precipitously for the first week, thereafter, crystalizing into a smaller repertoire, consistent with the selective attrition model of language development. Corticosterone-treated nestlings differed from unmanipulated birds and sham controls in several acoustic properties and crystallized a larger repertoire post-treatment. Our findings indicate babbling occurs during an early life-history stage in which corticosteroids help catalyse the transition from a universal learning programme to one finely tuned for the prevailing ecological environment, a potentially convergent scenario in human prelinguistic development.

Abstract Laser-plasma accelerators are compact linear accelerators based on the interaction of high-power lasers with plasma to form accelerating structures up to 1000 times smaller than standard radiofrequency cavities, and they come with an embedded X-ray source, namely betatron source, with unique properties: small source size and femtosecond pulse duration. A still unexplored possibility to exploit the betatron source comes from combining it with imaging methods able to encode multiple information like transmission and phase into a single-shot acquisition approach. In this work, we combine edge illumination-beam tracking (EI-BT) with a betatron X-ray source and present the demonstration of multimodal imaging (transmission, refraction, and scattering) with a compact light source down to the femtosecond timescale. The advantage of EI-BT is that it allows multimodal X-ray imaging technique, granting access to transmission, refraction and scattering signals from standard low-coherence laboratory X-ray sources in a single shot.

Abstract The journal Comparative Migration Studies has published a series of articles engaging with critiques of migrant integration. This piece wishes to contribute to such discussion, reflecting back on early critiques of integration as a concept and as a process, and reviewing more recent publications. The aim is to widen the reflection on decolonising the field by including urban postcolonial and southern instances, as well as insights from two funded projects.

Abstract Objective: To analyze the temporal trend and the spatial distribution of acquired syphilis in Mato Grosso, Brazil, between 2010 and 2021. Methods: This was an ecological study using notifications of acquired syphilis held on the Notifiable Health Conditions Information System. Detection rates were calculated by health macro-region and three-year periods (2010-2012, 2013-2015, 2016-2018, 2019-2021). The jointpoint method was used to calculate annual percentage change (APC). Thematic maps of Bayesian rates were built and distribution was analyzed using Local Moran. Results: The detection rate increased from 16.2 per 100,000 inhabitants in the first three-year period (2010-2012) to 70.0 in the last three-year period (2019-2021). The Central-North macro-region had the highest rate in the last three years (94.3/100,000 inhab.), while the highest upward trend occurred in the Central-Northwest macro-region, from 2013 to 2018 (APC = 50.2; 95%CI 26.3;78.6). There was an increase in Bayesian rates in most municipalities. Conclusion: There was a trend towards an increase in acquired syphilis, especially in the last two three-year periods.

Abstract Beam tracking X-ray Phase Contrast Imaging is a “Shack-Hartmann” type approach which uses a pre-sample mask to split the x-rays into “beamlets” which are interrogated by a detector with sufficient resolution. The ultimate spatial resolution is determined by the size of the mask apertures, however achieving this resolution level requires “stepping” the sample or the mask in increments equal to the aperture size (“dithering”). If an array of circular apertures is used (which also provides two-dimensional phase sensitivity) instead of long parallel slits, this stepping needs to be carried out in two directions, which lengthens scan times significantly. We present a mask design obtained by offsetting rows of circular apertures, allowing for two-dimensional sensitivity and isotropic resolution while requiring sample or mask stepping in one direction only. We present images of custom-built phantoms and biological specimens, demonstrating that quantitative phase retrieval and near aperture-limited spatial resolutions are obtained in two orthogonal directions.

Dark-field X-ray imaging is sensitive to the microstructure of a material. Here, the authors combine this with a neural network algorithm to provide efficient material discrimination, e.g., of explosives vs non-threat materials.

Abstract Multi-modal X-ray imaging allows the extraction of phase and dark-field (or “Ultra-small Angle Scatter”) images alongside conventional attenuation ones. Recently, scan-based systems using conventional sources that can simultaneously output the above three images on relatively large-size objects have been developed by various groups. One limitation is the need for some degree of spatial coherence, achieved either through the use of microfocal sources, or by placing an absorption grating in front of an extended source. Both these solutions limit the amount of flux available for imaging, with the latter also leading to a more complex setup with additional alignment requirements. Edge-illumination partly overcomes this as it was proven to work with focal spots of up to 100 micron. While high-flux, 100 micron focal spot sources do exist, their comparatively large footprint and high cost can be obstacles to widespread translation. A simple solution consists in placing a single slit in front of a large focal spot source. We used a tunable slit to study the system performance at various effective focal spot sizes, by extracting transmission, phase and dark-field images of the same specimens for a range of slit widths. We show that consistent, repeatable results are obtained for varying X-ray statistics and effective focal spot sizes. As the slit width is increased, the expected reduction in the raw differential phase peaks is observed, compensated for in the retrieval process by a broadened sensitivity function. This leads to the same values being correctly retrieved, but with a slightly larger error bar i.e. a reduction in phase sensitivity. Concurrently, a slight increase in the dark-field signal is also observed.

In Unare and Píritu Coastal Lagoons, a study was carried out to assess the effect of C, N, and P load contributions on the capability of the sediments to immobilize phosphates. To achieve the later, the geochemical data of the sediments were coupled to the P‐sorption index of Bache and Williams (IBW). In both lagoons, the sediments showed a pH > 7 because of calcareous sedimentation. The inorganic carbon values in the lagoons displayed a spatial distribution with higher concentrations toward the shores, that is defined by the carbonate lithology. On the contrary, the inner part of the lagoons was characterized by the presence of organic materials associated to the clay. The phosphorus content in the Unare Lagoon ranged from 290 to 625 mg kg−1, whereas in the Píritu Lagoon the values fluctuated between 213 and 1013 mg kg−1. The highest concentrations of phosphorus in both lagoons could be linked to sewage and runoff input from agricultural and livestock activities around the lagoon systems. The IBW displayed adsorption average values of 21.97 and 27.42 for Unare and Píritu Lagoon, respectively, corresponding to a rather low P sorption. In Unare Lagoon, the IBW showed positive correlations with C, N and Felabile but negative with P. However, in the Píritu Lagoon, despite the analogous lithology of the lagoons, a slightly positive non‐significative correlation between IBW and IC was only found. Although the sediments adsorb P with a rather low capacity, they can mitigate the eutrophication process in the studied lagoons. [ABSTRACT FROM AUTHOR]

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Topological superconductivity emerging in one- or two-dimensional hybrid materials is predicted as a key ingredient for quantum computing. However, not only the design of complex heterostructures is primordial for future applications but also the characterization of their electronic and structural properties at the atomic scale using the most advanced scanning probe microscopy techniques with functionalized tips. We report on the topographic signatures observed by scanning tunneling microscopy (STM) of carbon monoxide (CO) molecules, iron (Fe) atoms and sodium chloride (NaCl) islands deposited on superconducting Pb(111). For the CO adsorption a comparison with the Pb(110) substrate is demonstrated. We show a general propensity of these adsorbates to diffuse at low temperature under gentle scanning conditions. Our findings provide new insights into high-resolution probe microscopy imaging with terminated tips, decoupling atoms and molecules by NaCl islands or tip-induced lateral manipulation of iron atoms on top of the prototypical Pb(111) superconducting surface.

Resumo O Abrigo do Alvo, localizado no município de Analândia, São Paulo, apresenta registros rupestres, em sua maior parte compostos por gravuras, sobre substrato rochoso arenítico da Formação Botucatu. O abrigo foi originalmente registrado nos anos 1980 e, em 2012, novas intervenções foram realizadas no sítio, incluindo escavações e datações que inserem a ocupação mais antiga por volta de 7.500 anos cal AP. Neste artigo, apresenta-se uma análise detalhada dos registros rupestres localizados no Abrigo do Alvo, compostos majoritariamente por tridígitos, apresentando também linhas horizontais, linhas entrecruzadas, asteriscos, cúpules e figuras circulares. É abordado também o panorama geral do estado de conservação dos grafismos rupestres.