84 research outputs found

    The first super-Earth Detection from the High Cadence and High Radial Velocity Precision Dharma Planet Survey

    Get PDF
    The Dharma Planet Survey (DPS) aims to monitor about 150 nearby very bright FGKM dwarfs (within 50 pc) during 2016−-2020 for low-mass planet detection and characterization using the TOU very high resolution optical spectrograph (R≈\approx100,000, 380-900nm). TOU was initially mounted to the 2-m Automatic Spectroscopic Telescope at Fairborn Observatory in 2013-2015 to conduct a pilot survey, then moved to the dedicated 50-inch automatic telescope on Mt. Lemmon in 2016 to launch the survey. Here we report the first planet detection from DPS, a super-Earth candidate orbiting a bright K dwarf star, HD 26965. It is the second brightest star (V=4.4V=4.4 mag) on the sky with a super-Earth candidate. The planet candidate has a mass of 8.47±0.47MEarth\pm0.47M_{\rm Earth}, period of 42.38±0.0142.38\pm0.01 d, and eccentricity of 0.04−0.03+0.050.04^{+0.05}_{-0.03}. This RV signal was independently detected by Diaz et al. (2018), but they could not confirm if the signal is from a planet or from stellar activity. The orbital period of the planet is close to the rotation period of the star (39−-44.5 d) measured from stellar activity indicators. Our high precision photometric campaign and line bisector analysis of this star do not find any significant variations at the orbital period. Stellar RV jitters modeled from star spots and convection inhibition are also not strong enough to explain the RV signal detected. After further comparing RV data from the star's active magnetic phase and quiet magnetic phase, we conclude that the RV signal is due to planetary-reflex motion and not stellar activity.Comment: 13 pages, 17 figures, Accepted for publication in MNRA

    Friends or foes? migrants and sub-state nationalists in Europe

    Get PDF
    How do sub-state nationalists respond to the growing presence of cultural diversity in their ‘homelands’ resulting from migration? Sub-state nationalists in Europe, in ‘nations without states’ such as Catalonia and Scotland, have been challenging the traditional nation-state model for many decades. While the arguments in favour of autonomy or independence levelled by these movements have become more complex, sub-state nationalist movements remain grounded by their perceived national community that is distinct from the majority nation. Migration to the ‘homeland’ of a sub-state nation, then, presents a conundrum for sub-state elites that we label the ‘legitimation paradox’: too much internal diversity may undermine the claim to cultural distinctiveness. We engage with three common intervening variables thought to influence how sub-state nationalists confront the ‘legitimation paradox’: civic/ethnic nationalism, degree of political autonomy, and party competition. Our overarching argument is that none of these factors have a unidirectional or determinate effect on the sub-state nationalism-immigration nexus, which is why the nuanced case studies that comprise this Special Issue are worthwhile endeavours

    The first super-Earth detection from the high cadence and high radial velocity precision Dharma Planet Survey

    Get PDF
    The Dharma Planet Survey (DPS) aims to monitor about 150 nearby very bright FGKM dwarfs (within 50 pc) during 2016–2020 for low-mass planet detection and characterization using the TOU very high resolution optical spectrograph (⁠R≈100000⁠, 380–900 nm). TOU was initially mounted to the 2-m Automatic Spectroscopic Telescope at Fairborn Observatory in 2013–2015 to conduct a pilot survey, then moved to the dedicated 50-inch automatic telescope on Mt. Lemmon in 2016 to launch the survey. Here, we report the first planet detection from DPS, a super-Earth candidate orbiting a bright K dwarf star, HD 26965. It is the second brightest star (V = 4.4 mag) on the sky with a super-Earth candidate. The planet candidate has a mass of 8.47 ± 0.47MEarth, period of 42.38 ± 0.01 d, and eccentricity of 0.04+0.05−0.03⁠. This radial velocity (RV) signal was independently detected by DĂ­az et al., but they could not confirm if the signal is from a planet or stellar activity. The orbital period of the planet is close to the rotation period of the star (39–44.5 d) measured from stellar activity indicators. Our high precision photometric campaign and line bisector analysis of this star do not find any significant variations at the orbital period. Stellar RV jitters modelled from star-spots and convection inhibition are also not strong enough to explain the RV signal detected. After further comparing RV data from the star’s active magnetic phase and quiet magnetic phase, we conclude that the RV signal is due to planetary-reflex motion and not stellar activity

    On the discovery of stars, quasars, and galaxies in the Southern Hemisphere with S-PLUS DR2

    Get PDF
    This paper provides a catalogue of stars, quasars, and galaxies for the Southern Photometric Local Universe Survey Data Release 2 (S-PLUS DR2) in the Stripe 82 region. We show that a 12-band filter system (5 Sloan-like and 7 narrow bands) allows better performance for object classification than the usual analysis based solely on broad bands (regardless of infrared information). Moreover, we show that our classification is robust against missing values. Using spectroscopically confirmed sources retrieved from the Sloan Digital Sky Survey DR16 and DR14Q, we train a random forest classifier with the 12 S-PLUS magnitudes + 4 morphological features. A second random forest classifier is trained with the addition of the W1 (3.4 ÎŒm) and W2 (4.6 ÎŒm) magnitudes from the Wide-field Infrared Survey Explorer (WISE). Forty-four per cent of our catalogue have WISE counterparts and are provided with classification from both models. We achieve 95.76 per cent (52.47 per cent) of quasar purity, 95.88 per cent (92.24 per cent) of quasar completeness, 99.44 per cent (98.17 per cent) of star purity, 98.22 per cent (78.56 per cent) of star completeness, 98.04 per cent (81.39 per cent) of galaxy purity, and 98.8 per cent (85.37 per cent) of galaxy completeness for the first (second) classifier, for which the metrics were calculated on objects with (without) WISE counterpart. A total of 2926 787 objects that are not in our spectroscopic sample were labelled, obtaining 335 956 quasars, 1347 340 stars, and 1243 391 galaxies. From those, 7.4 per cent, 76.0 per cent, and 58.4 per cent were classified with probabilities above 80 per cent. The catalogue with classification and probabilities for Stripe 82 S-PLUS DR2 is available for download. © 2021 The Author(s).This work has been supported by a PhD fellowship to the lead author from Fundacao de Amparo Ă  Pesquisa do Estado de Sao Paulo (FAPESP), 2019/01312-2. LN also acknowledges the support of Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior -Brasil (CAPES) -Finance Code 001 and FAPESP through process number 2014/10566-4. LN also thanks the staff of the Astronomy department from the University of Florida, where part of this work was done; Marco Antonio dos Santos and Ulisses Manzo Castello for the technical support; Luis Manrique for the technical support, feedback, and discussions about Machine Learning; Christian Massao Tsujiguchi Takagi and Vin ' icius Amaral Haga for the feedback on the accessibility of the figures in this paper; Gustavo Oliveira Schwarz for building the database. CMdO acknowledges funding from FAPESP through grants 2009/542028 and 2019/26492-3 and funding from the Brazilian National Research Council (CNPq), through grant 309209/2019-6. NSTH acknowledges FAPESP (grants 2017/25835-9 and 2015/22308-2). CQ acknowledges support from FAPESP (grants 2015/11442-0 and 2019/06766-1). AM acknowledges FAPESP scholarship grant 2018/25671-9. CEB acknowledges FAPESP, grant 2016/12331-0. FA-F acknowledges funding for this work from FAPESP grant 2018/20977-2. LSJ acknowledges support from Brazilian agencies FAPESP (2019/10923-5) and CNPq (304819/201794). AAC acknowledges support from Fundacao de Amparo Ă  Pesquisa do Estado do Rio de Janeiro (FAPERJ; grant E26/203.186/2016) and CNPq (grants 304971/2016-2 and 401669/2016-5). EVL acknowledges funding for this work from CNPq grant 169181/2017-0 and CAPES grant 88887.470064/2019-00. MLB acknowledges FAPESP, grants 2018/09165-6 and 2019/23388-0. KMD acknowledges support from FAPERJ (grant E-26/203.184/2017), CNPq (grant 312702/2017-5) and the Serrapilheira Institute (grant Serra-1709-17357). AAC acknowledges support from FAPERJ (grant E26/203.186/2016), CNPq (grants 304971/2016-2 and 401669/2016-5), from the Universidad de Alicante under contract UATALENTO18-02, and from the State Agency for Research of the Spanish MCIU through the `Center of Excellence Severo Ochoa' award to the Instituto de AstrofĂ­sica de AndalucĂ­a (SEV-2017-0709). ARL acknowledges the financial support from CNPq through the PCI (Programa de Capacitacao Institucional) fellowship. The S-PLUS project, including the T80-South robotic telescope and the S-PLUS scientific survey, was founded as a partnership between FAPESP, the Observatorio Nacional (ON), the Federal University of Sergipe (UFS), and the Federal University of Santa Catarina (UFSC), with important financial and practical contributions from other collaborating institutes in Brazil, Chile (Universidad de La Serena), and Spain (Centro de Estudios de FĂ­sica del Cosmos de AragĂłn, CEFCA). We further acknowledge financial support from FAPESP, CNPq, CAPES, FAPERJ, and the Brazilian Innovation Agency (FINEP).Peer reviewe

    Application of the rainbow trout derived intestinal cell line (RTgutGC) for ecotoxicological studies: molecular and cellular responses following exposure to copper.

    Get PDF
    There is an acknowledged need for in vitro fish intestinal model to help understand dietary exposure to chemicals in the aquatic environment. The presence and use of such models is however largely restrictive due to technical difficulties in the culturing of enterocytes in general and the availability of appropriate established cell lines in particular. In this study, the rainbow trout (Oncorhynchus mykiss) intestinal derived cell line (RTgutGC) was used as a surrogate for the "gut sac" method. To facilitate comparison, RTgutGC cells were grown as monolayers (double-seeded) on permeable Transwell supports leading to a two-compartment intestinal model consisting of polarised epithelium. This two-compartment model divides the system into an upper apical (lumen) and a lower basolateral (portal blood) compartment. In our studies, these cells stained weakly for mucosubstances, expressed the tight junction protein ZO-1 in addition to E-cadherin and revealed the presence of polarised epithelium in addition to microvilli protrusions. The cells also revealed a comparable transepithelial electrical resistance (TEER) to the in vivo situation. Importantly, the cell line tolerated apical saline (1:1 ratio) thus mimicking the intact organ to allow assessment of uptake of compounds across the intestine. Following an exposure over 72 h, our study demonstrated that the RTgutGC cell line under sub-lethal concentrations of copper sulphate (Cu) and modified saline solutions demonstrated uptake of the metal with saturation levels comparable to short term ex situ gut sac preparations. Gene expression analysis revealed no significant influence of pH or time on mRNA expression levels of key stress related genes (i.e. CYP3A, GST, mtA, Pgp and SOD) in the Transwell model. However, significant positive correlations were found between all genes investigated suggesting a co-operative relationship amongst the genes studied. When the outlined characteristics of the cell line are combined with the division of compartments, the RTgutGC double seeded model represents a potential animal replacement model for ecotoxicological studies. Overall, this model could be used to study the effects and predict aquatic gastrointestinal permeability of metals and other environmentally relevant contaminants in a cost effective and high throughput manner

    Uncovering Ubiquitin and Ubiquitin-like Signaling Networks

    Get PDF
    Microscopic imaging and technolog

    Adopting a child perspective for exposome research on mental health and cognitive development - Conceptualisation and opportunities.

    Get PDF
    Mental disorders among children and adolescents pose a significant global challenge. The exposome framework covering the totality of internal, social and physical exposures over a lifetime provides opportunities to better understand the causes of and processes related to mental health, and cognitive functioning. The paper presents a conceptual framework on exposome, mental health, and cognitive development in children and adolescents, with potential mediating pathways, providing a possibility for interventions along the life course. The paper underscores the significance of adopting a child perspective to the exposome, acknowledging children's specific vulnerability, including differential exposures, susceptibility of effects and capacity to respond; their susceptibility during development and growth, highlighting neurodevelopmental processes from conception to young adulthood that are highly sensitive to external exposures. Further, critical periods when exposures may have significant effects on a child's development and future health are addressed. The paper stresses that children's behaviour, physiology, activity pattern and place for activities make them differently vulnerable to environmental pollutants, and calls for child-specific assessment methods, currently lacking within today's health frameworks. The importance of understanding the interplay between structure and agency is emphasized, where agency is guided by social structures and practices and vice-versa. An intersectional approach that acknowledges the interplay of social and physical exposures as well as a global and rural perspective on exposome is further pointed out. To advance the exposome field, interdisciplinary efforts that involve multiple scientific disciplines are crucial. By adopting a child perspective and incorporating an exposome approach, we can gain a comprehensive understanding of how exposures impact children's mental health and cognitive development leading to better outcomes

    Fossil record of stem groups employed in evaluating the chronogram of insects (Arthropoda: Hexapoda)

    Get PDF
    Insecta s. str. (=Ectognatha), comprise the largest and most diversified group of living organisms, accounting for roughly half of the biodiversity on Earth. Understanding insect relationships and the specific time intervals for their episodes of radiation and extinction are critical to any comprehensive perspective on evolutionary events. Although some deeper nodes have been resolved congruently, the complete evolution of insects has remained obscure due to the lack of direct fossil evidence. Besides, various evolutionary phases of insects and the corresponding driving forces of diversification remain to be recognized. In this study, a comprehensive sample of all insect orders was used to reconstruct their phylogenetic relationships and estimate deep divergences. The phylogenetic relationships of insect orders were congruently recovered by Bayesian inference and maximum likelihood analyses. A complete timescale of divergences based on an uncorrelated log-normal relaxed clock model was established among all lineages of winged insects. The inferred timescale for various nodes are congruent with major historical events including the increase of atmospheric oxygen in the Late Silurian and earliest Devonian, the radiation of vascular plants in the Devonian, and with the available fossil record of the stem groups to various insect lineages in the Devonian and Carboniferous. © The Author(s) 2016
    • 

    corecore