We propose that several short-duration events observed in past stellar occultations by Chiron were produced by ring material. Some similarities between these events and the characteristics of ...Chariklo’s rings could indicate common mechanisms around centaurs. From a reanalysis of the stellar occultation data in the literature, we determined two possible orientations of the pole of Chiron’s rings, with ecliptic coordinates λ = (352 ± 10)°, β = (37 ± 10)° or λ = (144 ± 10)°, β = (24 ± 10)°. The mean radius of the rings is (324 ± 10) km. One can use the rotational lightcurve amplitude of Chiron at different epochs to distinguish between the two solutions for the pole. Both solutions imply a lower lightcurve amplitude in 2013 than in 1988, when the rotational lightcurve was first determined. We derived Chiron’s rotational lightcurve in 2013 from observations at the 1.23 m CAHA telescope, and indeed its amplitude was smaller than in 1988. We also present a rotational lightcurve in 2000 from images taken at the CASLEO 2.15 m telescope that is consistent with our predictions. Out of the two poles, the λ = (144 ± 10)°, β = (24 ± 10)° solution provides a better match to a compilation of rotational lightcurve amplitudes from the literature and those presented here. We also show that using this preferred pole orientation, Chiron’s long-term brightness variations are compatible with a simple model that incorporates the changing brightness of the rings while the tilt angle with respect to the Earth is changing with time. Also, the variability of the water ice band in Chiron’s spectra as seen in the literature can be explained to a large degree by an icy ring system whose tilt angle changes with time and whose composition includes water ice, analogously to the case of Chariklo. We present several possible formation scenarios for the rings from qualitative points of view and speculate on why rings might be common in centaurs. We also speculate on whether the known bimodal color distribution of the centaurs could be due to centaurs with rings and centaurs without rings.
Context.
Gliese-832 (GJ 832) is an M2V star hosting a massive planet on a decade-long orbit, GJ 832b, discovered by radial velocity (RV). Later, a super Earth or mini-Neptune orbiting within the ...stellar habitable zone was reported (GJ 832c). The recently determined stellar rotation period (45.7 ± 9.3 days) is close to the orbital period of putative planet c (35.68 ± 0.03 days).
Aims.
We aim to confirm or dismiss the planetary nature of the RV signature attributed to GJ 832c, by adding 119 new RV data points, new photometric data, and an analysis of the spectroscopic stellar activity indicators. Additionally, we update the orbital parameters of the planetary system and search for additional signals.
Methods.
We performed a frequency content analysis of the RVs to search for periodic and stable signals. Radial velocity time series were modelled with Keplerians and Gaussian process (GP) regressions alongside activity indicators to subsequently compare them within a Bayesian framework.
Results.
We updated the stellar rotational period of GJ 832 from activity indicators, obtaining 37.5
+1.4
-1.5
days, improving the precision by a factor of 6. The new photometric data are in agreement with this value. We detected an RV signal near 18 days (FAP < 4.6%), which is half of the stellar rotation period. Two Keplerians alone fail at modelling GJ 832b and a second planet with a 35-day orbital period. Moreover, the Bayesian evidence from the GP analysis of the RV data with simultaneous activity indices prefers a model without a second Keplerian, therefore negating the existence of planet c.
Abstract Body
Uaccompanied migrant youth represent an at-risk population given the complexity of negotiating adolescence in a new culture, isolated from family and friends, without a secure base and ...subject to discrimination. In addition, many unaccompanied migrant youth have been subject to considerable trauma prior to, during, and post migration. In Spain, as in many countries, the residential, care, and mental health services are not adapted to the specific and complex needs of this population, and to that end complex not only are the youth not well served but providers are increasingly frustrated. The figure of the community health agent has been widely recognized as one that can function as an effective bridge between systems/institutions and marginalized and vulnerable populations. In this presentation we will describe an ongoing project that trains unaccompanied migrant youth who show promise in their cultural adaptation in the areas of cultural competence, mental health care and substance abuse to function as community health agents (or peer counselors) consistent with models of cultural consultation.
Disclosure
No significant relationships.
The number of UMY in Spain is increasing, since the early 1990s, mostly coming from the Maghreb, although the number of those coming from different sub-Saharan African countries has gradually ...increased. Most of them leave their countries fleeing poverty, violence, and in search of better opportunities. They may be influenced by traumatic experiences and social stressors that can lead to emotional distress and mental health problems. They have particular needs and characteristics, so the local Child Protection Systems need to adapt their procedures to facilitate the youngsters’ social Integration and psychosocial development. This presentation will describe an ongoing project being carried out in Catalonia, the main objective is to guarantee the right to mental health of UMY in the Protection System through culturally competent biopsychosocial care, and to effectively coordinate care between the public mental health network and the Child Protection System. Finally, through training and the acquisition of competencies, the aim is to avoid burnout in professionals who care for these youths on the front line. The approach is consistent with the cultural consultation models developed in Montreal and London with the goal of providing structural support for localized and culturally competent responses. This project, to be developed over two years, has four main subprojects: 1. On-line training for professionals in “Cultural competence in mental health and psychosocial intervention”. 2. Training of “peer” UMY as “Community Mental Health Agents”. 3. Creation and implementation of multidisciplinary groups of psychosocial intervention. 4. Culturally competent psychiatric and psychological assessment.
Disclosure
No significant relationships.
ABSTRACT
Small low-mass stars are favourable targets for the detection of rocky habitable planets. In particular, planetary systems in the solar neighbourhood are interesting and suitable for precise ...characterization. The RedDots campaigns seek to discover rocky planets orbiting nearby low-mass stars. The 2018 campaign targeted GJ 1061, which is the 20th nearest star to the Sun. For three consecutive months we obtained nightly, high-precision radial velocity measurements with the HARPS spectrograph. We analysed these data together with archival HARPS data. We report the detection of three planet candidates with periods of 3.204 ± 0.001, 6.689 ± 0.005, and 13.03 ± 0.03 d, which are close to 1:2:4 period commensurability. After several considerations related to the properties of the noise and sampling, we conclude that a fourth signal is most likely explained by stellar rotation, although it may be due to a planet. The proposed three-planet system (and the potential four-planet solution) is long-term dynamically stable. Planet–planet gravitational interactions are below our current detection threshold. The minimum masses of the three planets range from 1.4 ± 0.2 to 1.8 ± 0.3 M⊕. Planet d, with msin i = 1.64 ± 0.24 M⊕, receives a similar amount of energy as Earth receives from the Sun. Consequently it lies within the liquid-water habitable zone of the star and has a similar equilibrium temperature to Earth. GJ 1061 has very similar properties to Proxima Centauri but activity indices point to lower levels of stellar activity.
In the following study, displaced Puerto Rican mothers and I created and explored a learning space -- culture circles -- that engaged participants in a critical cycle of problem posing, dialogue, and ...problem solving in relation to their experiences in the receiving Pennsylvania community. Using a qualitative, ethnographic approach, the study drew from Critical Pedagogy (CP), raciolinguistics, and a Community Cultural Wealth (CCW) framework to inform data collection and analysis. Individual interviews, culture circle meeting recordings, field notes, and digital artefacts created by four focal participants help illustrate how these mothers navigate the US school system and the wider receiving community in southern Pennsylvania. Moreover, the data reflect how racism in this context is based predominantly on families' language practices. Despite mothers facing significant challenges due to race/ethnicity, language, class, and gender, this study highlights the conversations that displaced Puerto Rican mothers engaged in regarding the impact racism had in their everyday lives. Furthermore, the space we created allowed participants to share and model their accumulated linguistic, social, and resistant capital for their children's academic success.
We present results for the short-term variability of binary trans-Neptunian objects (BTNOs). We performed CCD photometric observations using the 3.58 m Telescopio Nazionale Galileo (TNG), the 1.5 m ...Sierra Nevada Observatory (OSN) telescope, and the 1.23 m Centro Astronómico Hispano Alemán (CAHA) telescope at Calar Alto Observatory. We present results based on five years of observations and report the short-term variability of six BTNOs. Our sample contains three classical objects: (174567) 2003 MW12, or Varda, (120347) 2004 SB60, or Salacia, and 2002 VT130; one detached disk object: (229762) 2007 UK126; and two resonant objects: (341520) 2007 TY430 and (38628) 2000 EB173, or Huya. For each target, possible rotational periods and/or photometric amplitudes are reported. We also derived some physical properties from their light curves, such as density, primary and secondary sizes, and albedo. We compiled and analyzed a vast light curve database for TNOs including centaurs to determine the light-curve amplitude and spin frequency distributions for the binary and non-binary populations. The mean rotational periods, from the Maxwellian fits to the frequency distributions, are 8.63 ± 0.52 h for the entire sample, 8.37 ± 0.58 h for the sample without the binary population, and 10.11 ± 1.19 h for the binary population alone. Because the centaurs are collisionally more evolved, their rotational periods might not be so primordial. We computed a mean rotational period, from the Maxwellian fit, of 8.86 ± 0.58 h for the sample without the centaur population, and of 8.64 ± 0.67 h considering a sample without the binary and the centaur populations. According to this analysis, regular TNOs spin faster than binaries, which is compatible with the tidal interaction of the binaries. Finally, we examined possible formation models for several systems studied in this work and by our team in previous papers.
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In the context of replacing animal proteins in food matrices, rice proteins (RP) become promised because they come from an abundant plant source, are hypoallergenic, and have high ...digestibility and nutritional value. However, commercial protein isolates obtained by spray drying have low solubility and poor functionality, especially in their isoelectric point. One way to modify these properties is through interaction with polysaccharides, such as gum arabic (GA). Therefore, this work aims to evaluate the effects of pH and GA concentration on the interaction and emulsifying activity of RP:GA coacervates. First, the effects of pH (2.5 to 7.0) and GA concentrations (0.2 to 1.0 wt%, giving rise to RP:GA mass ratios of 1:0.2 to 1:1.0) in RP:GA blends were evaluated. The results demonstrated that biopolymers present opposite net charges at pH between 2.5 and 4.0. At pH 3.0, insoluble coacervates with complete charge neutralization were formed by electrostatic interactions, while at pH 5.0 it was observed that the presence of GA prevented the RP massive aggregation. Second, selected blends with 0.4 or 1.0 wt% of GA (RP:GA mass ratios of 1:0.4 or 1:1.0) at pH 3.0 or 5.0 were tested for their ability to stabilize oil-in-water emulsions. The emulsions were characterized for 21 days. It was observed that the GA increased the stability of RP emulsions, regardless of the pH and polysaccharide concentration. Taken together, our results show that it is possible to combine RP and GA to improve the emulsifying properties of these plant proteins at pH conditions close to their isoelectric point, expanding the possibility of implementation in food systems.
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