ARCHI: pipeline for light curve extraction of CHEOPS background star

High precision time series photometry from space is being used for a number of scientific cases. In this context, the recently launched CHEOPS (ESA) mission promises to bring 20 ppm precision over an exposure time of 6 hours, when targeting nearby bright stars, having in mind the detailed characterization of exoplanetary systems through transit measurements. However, the official CHEOPS (ESA) mission pipeline only provides photometry for the main target (the central star in the field). In order to explore the potential of CHEOPS photometry for all stars in the field, in this paper we present archi, an additional open-source pipeline module{\dag}to analyse the background stars present in the image. As archi uses the official Data Reduction Pipeline data as input, it is not meant to be used as independent tool to process raw CHEOPS data but, instead, to be used as an add-on to the official pipeline. We test archi using CHEOPS simulated images, and show that photometry of background stars in CHEOPS images is only slightly degraded (by a factor of 2 to 3) with respect to the main target. This opens a potential for the use of CHEOPS to produce photometric time series of several close-by targets at once, as well as to use different stars in the image to calibrate systematic errors. We also show one clear scientific application where the study of the companion light curve can be important for the understanding of the contamination on the main target.Comment: 14 pages, 13 figures, accepted for publication in MNRAS, all code available at https://github.com/Kamuish/arch

Geochronology and geochemistry of lithologies of the Tabuaço W-prospect area (Northern Portugal)

This work is focussed on lithologies occurring at Quinta de São Pedro das Águias, which is located in the Tabuaço prospect (an area of 45 km2 where exploration for W-skarn deposits is taking place, in northern Portugal, close to the Douro valley). At Quinta de São Pedro das Águias several lithologies are recognized: “normal” phyllites, black phyllites (graphite-bearing), marbles, calcsilicate (s.s.) rocks and skarns (sometimes, scheelite-bearing), belonging to the Bateiras Formation, of the Douro Group (one of the two major subdivisions of the Neoproterozoic-Cambrian Dúrico-Beirão Supergroup); Paredes da Beira-Tabuaço granite; several aplitic and pegmatitic bodies. The studied area belongs to the Central Iberian Zone, a geotectonic unit of the Iberian Variscan Chain. Rb-Sr isotope analyses done in the scope of this work, provided a 316 ± 7 Ma whole-rock isochron (MSWD = 1.7; initial 87Sr/86Sr = 0.7146) for the granitoids, using the 87Rb decay constant recently recommended by IUPAC-IUGS (Villa et al., 2015). This date is interpreted here as the emplacement age of those rocks, during a late stage of the Variscan D3. The granite revealed a S-type nature, namely because it is a muscovite granite, it shows a peraluminous composition (average A/CNK = 1.28), and the Sr and Nd isotope fingerprints (-8.9 ≤ εNd316 ≤ -7.8; +0.7105 ≤ [87Sr/86Sr]316 ≤ 0.7182) fit into the composition of metasedimentary crust. The analysed phyllites show the following isotopic compositions: -9.7 ≤ εNd316 ≤ -8.2; +0.7148 ≤ [87Sr/86Sr]316 ≤ 0.7188. Therefore, the isotope signatures, at 316 Ma, of the granite and of the studied metapelites overlap, suggesting that the parental magma was generated by anatexis of Grupo do Douro metasediments. According to their petrographic, geochemical and isotopic features, aplites and pegmatites are viewed as extreme differentiates from the granite. São Pedro das Águias metapelites show biotite zone parageneses. Geochemically, their REE normalized patterns are very similar to those displayed by NIBAS and by other upper crustal reference compositions. Isotopically, especially due to their lower εNd316, the studied metapelites are clearly distinct from the Grupo das Beiras metasediments (the other major division of the Dúrico-Beirão Supergroup), and, instead, they resemble other metasedimentary units of the Iberian Massif. Several lines of evidence, namely the isotope data (-8.1 ≤ εNd316 ≤ -6.4; +0.7090 ≤ [87Sr/86Sr]316 ≤ 0.7102) and the occurrence of fine intercalations of sub-mm layers enriched in phyllosilicates, suggest that calcsilicate (s.l.) rocks owe their composition not only to metasomatism that accompanied the granite intrusion, but also to an inheritance from their protoliths, which should have resulted from mixed sedimentation, both chemical and terrigenous

Geochronology and isotope geochemistry of granitoids and metasediments of São Pedro das Águias area (Tabuaço W project)

As litologias identificadas na área da Quinta de São Pedro das Águias correspondem a: xistos biotíticos, xistos negros, mármores, rochas calcossilicatadas s.s. e skarns da sequência metassedimentar da Formação de Bateiras, pertencente ao Grupo do Douro do CXG;granito de Paredes da Beira-Tabuaço; vários corpos aplíticos e pegmatíticos. Para as litologias granitoides, foi obtida uma isócrona Rb-Sr de 311±7 Ma (MSWD=1,7; 87Sr/86Sr inicial = 0,7146), a qual é aqui interpretada como datando a sua instalação durante uma etapa tardia da D3 varisca. O granito revela caraterísticas do tipo S, nomeadamente por ser moscovítico e peraluminoso (A/CNK médio = 1,28), e ter assinatura isotópica claramente compatível com crosta metassedimentar (-8,9≤εNd311≤-7,8; +129≤εSr311≤+192). A sobreposição da assinatura isotópica do granito com a dos metapelitos encaixantes indica que o magma parental foi provavelmente gerado por anatexia de metassedimentos do Grupo do Douro. Os metapelitos estudados são, do ponto de vista isotópico, em particular por apresentarem valores mais baixos de εNd311, claramente distintos dos metassedimentos do CXG do Grupo das Beiras, assemelhando-se, em contrapartida, a outras unidades metassedimentares do Maciço Ibérico.In the area of Quinta de São Pedro das Águias, the following lithologies were identified: biotite-zone “normal” and black phyllites, marbles, calcsilicate (s.s.) rocks and skarns, belonging to the Bateiras Formation, of the Douro Group of the CXG; Paredes da Beira-Tabuaço granite; several aplitic and pegmatitic bodies. Rb-Sr isotope analyses provided a 311±7 Ma whole-rock isochron (MSWD=1.7; initial 87Sr/86Sr = 0,7146) for the granitoids. This date is interpreted here as the emplacement age of the granitoid magmas, during a late stage of the Variscan D3. The granite revealed a S-type nature, namely because it is a muscovite granite, it shows a peraluminous composition (average A/CNK = 1.28), and the Sr and Nd isotope fingerprints (-8.9≤εNd311≤-7.8; +129≤εSr311≤+192) fit into the composition of metasedimentary crust. The isotope signatures, at 311 Ma, of the granite and of the studied metapelites overlap each other, suggesting that the parental magma was generated by anatexis of Grupo do Douro metasediments. Isotopically, especially due to their lower εNd311, the studied metapelites are clearly distinct from the Grupo das Beiras metasediments (the other major division of the CXG), and, instead, they resemble other metasedimentary units of the Iberian Massif

Selection of a new peptide homing SK-BR-3 breast cancer cells

Breast cancer diagnosis remains a challenge, mostly due to its heterogeneity. This reality translates in delayed treatments, increasing treatment aggressiveness and lower chances of overall survival. The conventional detection techniques, although becoming increasingly sophisticated each year, still lack the ability to provide reliable conclusions without being time consuming, expensive and uncomfortable for the patients. The identification of novel biomarkers for breast cancer research is therefore of utmost relevance for an early diagnosis. Moreover, breast cancer specific peptide moieties can be used to develop novel targeted drug delivery systems. In this work we used phage display to identify a novel peptide with specificity to the SK-BR-3 breast cancer cell line. Cytometry assays confirmed its specificity, while bioinformatics and docking studies predicted the potential biomarkers at the SK-BR-3 cells surface. These findings can be potentially useful in the clinical context, contributing to more specific and targeted therapeutic solutions against HER2-positive breast cancer subtypes.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Débora Ferreira and Ana Cláudia Pereira are recipient of fellowships supported by a doctoral advanced training (call NORTE-69-2015-15) funded by the European Social Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Cátia Santos-Pereira acknowledges the PhD fellowship PD/BD/128032/2016 funded by FCT under the scope of the doctoral programme in Applied and Environmental Microbiology (DP_AEM). The authors also acknowledge César Pimenta from NOVA Institute of Chemical and Biological Technology António Xavier (NOVA ITQB) for the docking insights.info:eu-repo/semantics/publishedVersio

On the Nature of the Core of α Centauri A: The Impact of the Metallicity Mixture

Forward asteroseismic modeling plays an important role toward a complete understanding of the physics taking place in deep stellar interiors. With a dynamical mass in the range over which models develop convective cores while in the main sequence, the solar-like oscillator α Centauri A presents itself as an interesting case study. We address the impact of varying the metallicity mixture on the determination of the energy transport process at work in the core of α Centauri A. We find that ≳ 70% of models reproducing the revised dynamical mass of α Centauri A have convective cores, regardless of the metallicity mixture adopted. This is consistent with the findings of Nsamba et al., where nuclear reaction rates were varied instead. Given these results, we propose that α Centauri A be adopted in the calibration of stellar model parameters when modeling solar-like stars with convective cores

Potential biological properties of lycopene in a self-emulsifying drug delivery system

In recent years, lycopene has been highlighted due to its antioxidant and anti-inflammatory properties, associated with a beneficial effect on human health. The aim of this study was to advance the studies of antioxidant and anti-inflammatory mechanisms on human keratinocytes cells (HaCaT) of a self-emulsifying drug delivery system (SEDDS) loaded with lycopene purified from red guava (nanoLPG). The characteristics of nanoLPG were a hydrodynamic diameter of 205 nm, a polydispersity index of 0.21 and a zeta potential of −20.57, providing physical stability for the nanosystem. NanoLPG demonstrated antioxidant capacity, as shown using the ORAC methodology, and prevented DNA degradation (DNA agarose). Proinflammatory activity was evaluated by quantifying the cytokines TNF-α, IL-6 and IL-8, with only IL-8 showing a significant increase (p < 0.0001). NanoLPG showed greater inhibition of the tyrosinase and elastase enzymes, involved in the skin aging process, compared to purified lycopene (LPG). In vitro treatment for 24 h with 5.0 µg/mL of nanoLPG did not affect the viability of HaCaT cells. The ultrastructure of HaCaT cells demonstrated the maintenance of morphology. This contrasts with endoplasmic reticulum stresses and autophagic vacuoles when treated with LPG after stimulation or not with LPS. Therefore, the use of lycopene in a nanoemulsion may be beneficial in strategies and products associated with skin health.info:eu-repo/semantics/publishedVersio

TESS asteroseismology of the known red-giant host stars HD 212771 and HD 203949

International audienc

Review of low-cost sensors for indoor air quality: Features and applications

Humans spend the majority of their time indoors, where they are potentially exposed to hazardous pollutants. Within this context, over the past few years, there has been an upsurge of low-cost sensors (LCS) for the measurement of indoor air pollutants, motivated both by recent technological advances and by increased awareness of indoor air quality (IAQ) and its potential negative health impacts. Although not meeting the performance requirements for reference regulatory-equivalent monitoring indoors, LCS can provide informative measurements, offering an opportunity for high-resolution monitoring, emission source identification, exposure mitigation and managing IAQ and energy efficiency, among others. This article discusses the strengths and limitations that LCS offer for applications in the field of IAQ monitoring; it provides an overview of existing sensor technologies and gives recommendations for different indoor applications, considering their performance in the complex indoor environment and discussing future trends