Signatures of rocky planet engulfment in HAT-P-4. Implications for chemical tagging studies

Aims. To explore the possible chemical signature of planet formation in the binary system HAT-P-4, by studying abundance vs condensation temperature Tc trends. The star HAT-P-4 hosts a planet detected by transits while its stellar companion does not have any detected planet. We also study the Lithium content, which could shed light on the problem of Li depletion in exoplanet host stars. Conclusions. The exoplanet host star HAT-P-4 is found to be ~0.1 dex more metal rich than its companion, which is one of the highest differences in metallicity observed in similar systems. This could have important implications for chemical tagging studies, disentangling groups of stars with a common origin. We rule out a possible peculiar composition for each star as lambda Boo, delta Scuti or a Blue Straggler. The star HAT-P-4 is enhanced in refractory elements relative to volatile when compared to its stellar companion. Notably, the Lithium abundance in HAT-P-4 is greater than in its companion by ~0.3 dex, which is contrary to the model that explains the Lithium depletion by the presence of planets. We propose a scenario where, at the time of planet formation, the star HAT-P-4 locked the inner refractory material in planetesimals and rocky planets, and formed the outer gas giant planet at a greater distance. The refractories were then accreted onto the star, possibly due to the migration of the giant planet. This explains the higher metallicity, the higher Lithium content, and the negative Tc trend detected. A similar scenario was recently proposed for the solar twin star HIP 68468, which is in some aspects similar to HAT-P-4. We estimate a mass of at least Mrock ~ 10 Mearth locked in refractory material in order to reproduce the observed Tc trends and metallicity.Comment: 5 pages, 6 figures, A&A Letters accepte

VALES: IV. Exploring the transition of star formation efficiencies between normal and starburst galaxies using APEX/SEPIA Band-5 and ALMA at low redshift

In this work we present new APEX/SEPIA Band-5 observations targeting the CO ($J=2\text{-}1$) emission line of 24 Herschel-detected galaxies at $z=0.1-0.2$. Combining this sample {with} our recent new Valpara\'iso ALMA Line Emission Survey (VALES), we investigate the star formation efficiencies (SFEs = SFR/$M_{\rm H_{2}}$) of galaxies at low redshift. We find the SFE of our sample bridges the gap between normal star-forming galaxies and Ultra-Luminous Infrared Galaxies (ULIRGs), which are thought to be triggered by different star formation modes. Considering the $\rm SFE'$ as the SFR and the $L'_{\rm CO}$ ratio, our data show a continuous and smooth increment as a function of infrared luminosity (or star formation rate) with a scatter about 0.5 dex, instead of a steep jump with a bimodal behaviour. This result is due to the use of a sample with a much larger range of sSFR/sSFR$_{\rm ms}$ using LIRGs, with luminosities covering the range between normal and ULIRGs. We conclude that the main parameters controlling the scatter of the SFE in star-forming galaxies are the systematic uncertainty of the $\alpha_{\rm CO}$ conversion factor, the gas fraction and physical size.Comment: 9pages, 7 figures, 1 table, accepted for publication in MNRA

Diabetes y su impacto en el territorio periodontal

ResumenDiabetes y enfermedad periodontal corresponden probablemente al mejor ejemplo de cómo una enfermedad sistémica puede tener un efecto en el territorio periodontal. Si bien esta asociación ha sido extensamente estudiada, muchas de las asociaciones propuestas presentan contradicciones. En la presente revisión de la literatura se analizan los siguientes tópicos relevantes para la práctica clínica en periodoncia e implantología: i) Identificación de enfermedad periodontal severa y su capacidad para diagnosticar casos de diabetes; ii) Efectos de la diabetes sobre la enfermedad periodontal; iii) Efectos de la diabetes sobre la reparación periodontal y periimplantaria; iv) Efecto del tratamiento periodontal sobre el control metabólico de la diabetes.AbstractDiabetes and periodontal disease correspond to conditions that probably exemplify how a systemic disease may have a strong impact in the periodontium. Although this association has been studied for several years, many of these studies still show contradictory results. The present review analyses the following questions relevant for the clinician in the fields of periodontology: i) Value of the diagnosis of severe periodontitis and its capacity to identify previously un-diagnosed cases of diabetes; ii) Effects of diabetes on periodontal disease; iii) Effects of diabetes on periodontal and periimplant tissue repair and regeneration and; iv) Effect of periodontal therapy on the metabolic control of diabetes

The ALMA Frontier Fields Survey - IV. Lensing-corrected 1.1 mm number counts in Abell 2744, MACSJ0416.1-2403 and MACSJ1149.5+2223

[abridged] Characterizing the number counts of faint, dusty star-forming galaxies is currently a challenge even for deep, high-resolution observations in the FIR-to-mm regime. They are predicted to account for approximately half of the total extragalactic background light at those wavelengths. Searching for dusty star-forming galaxies behind massive galaxy clusters benefits from strong lensing, enhancing their measured emission while increasing spatial resolution. Derived number counts depend, however, on mass reconstruction models that properly constrain these clusters. We estimate the 1.1 mm number counts along the line of sight of three galaxy clusters, i.e. Abell 2744, MACSJ0416.1-2403 and MACSJ1149.5+2223, which are part of the ALMA Frontier Fields Survey. We perform detailed simulations to correct these counts for lensing effects. We use several publicly available lensing models for the galaxy clusters to derive the intrinsic flux densities of our sources. We perform Monte Carlo simulations of the number counts for a detailed treatment of the uncertainties in the magnifications and adopted source redshifts. We find an overall agreement among the number counts derived for the different lens models, despite their systematic variations regarding source magnifications and effective areas. Our number counts span ~2.5 dex in demagnified flux density, from several mJy down to tens of uJy. Our number counts are consistent with recent estimates from deep ALMA observations at a 3$\sigma$ level. Below $\approx$ 0.1 mJy, however, our cumulative counts are lower by $\approx$ 1 dex, suggesting a flattening in the number counts. In our deepest ALMA mosaic, we estimate number counts for intrinsic flux densities $\approx$ 4 times fainter than the rms level. This highlights the potential of probing the sub-10 uJy population in larger samples of galaxy cluster fields with deeper ALMA observations.Comment: 19 pages, 14 figures, 3 tables. Accepted for publication in A&

Cyrhetrenylaniline and new organometallic phenylimines derived from 4- and 5-nitrothiophene: Synthesis, characterization, X-Ray structures, electrochemistry and in vitro anti-T. brucei activity

A novel series of cyrhetrenyl (3a-4a) and ferrocenyl (3b-4b) Schiff bases were synthesized through a condensation reaction, between the known 4-ferrocenylaniline (2b) or the unreported 4-cyhretrenylaniline (2a) with 4- or 5-nitrothiophenecarboxaldehyde. The structure of 2a and the new Schiff bases have been elucidated using conventional spectroscopic techniques (FT-IR, 1H and 13C NMR), mass spectrometry, and single-crystal X-ray diffraction analysis of compounds 2a, 4a and 3b. Cyclic voltammetry of organometallic phenylimines derived from 5-nitrothiophene showed NO2 group reduction potentials (E1/2z 0.575 V) that were more anodic than those registered for their 4-nitro analogues (E1/2z 0.981 V). All organometallic imines were tested against the bloodstream form of Trypanosoma brucei. Evaluation indicated that the most active complexes are the 5-nitrothiophene derivatives, 4a, which were remarkably more active than nifurtimox. In addition, complex 4b resulted in less toxicity to host L6 cells than nifurtimox. The results revealed that the electronic effects of cyrhetrene and ferrocene are not an influential factor in E1/2 and anti-Trypanosoma brucei activity for these new imines, which is probably due to the non-coplanarity of the [(h5-C5H4)-C6H4-N=CH-(C4H2S)] system

Obtención de vidrio a partir de residuos de la minería del estaño en Bolivia

Manufacturing of glass from tin mining tailings in Bolivia Tailings from mining activities in Bolivia represent an environmental problem. In the vicinity of the tin mines of Llallagua,Potosí department, there are large dumps and tailings. We present a study of the use of these wastes as raw materials for the manufacture of glass. This procedure aims to contribute to environmental remediation of mining areas through the vitrification, a process which offers an alternative for stabilization of hazardous waste. In addition, the marketing of the obtained product would provide an additional income to the mining areas. For this study three samples of mining waste, with grain size between sand and silt, were used. The chemical composition of these raw materials, determined by X-ray fluorescence, is granitic, with high contents of heavy metals. On the basis of its composition, glass were made from silica glass by adding CaCO3 and Na2CO3. The thermal cycle has been determined from TDA. Tg values of glass range from 626º to 709 °C. Leaching tests of the obtained glasses confirm their capacity to retain heavy metals

Elemental abundances differences in the massive planet-hosting wide binary HD 196067-68

It has been suggested that small chemical anomalies observed in planet-hosting wide binary systems could be due to planet signatures, where the role of the planetary mass is still unknown. We search for a possible planet signature by analyzing the Tc trends in the remarkable binary system HD196067-HD196068. At the moment, only HD196067 is known to host a planet which is near the brown dwarf regime. We take advantage of the strong physical similarity between both stars, which is crucial to achieving the highest possible precision in stellar parameters and elemental chemical abundances. This system gives us a unique opportunity to explore if a possible depletion of refractories in a binary system could be inhibited by the presence of a massive planet. We performed a line-by-line chemical differential study, employing the non-solar-scaled opacities, in order to reach the highest precision in the calculations. After differentially comparing both stars, HD196067 displays a clear deficiency in refractory elements in the Tc plane, a lower iron content (0.051 dex) and also a lower Li I content (0.14 dex) than its companion. In addition, the differential abundances reveal a Tc trend. These targets represent the first cases of an abundance difference around a binary system hosting a super-Jupiter. Although we explored several scenarios to explain the chemical anomalies, none of them can be entirely ruled out. Additional monitoring of the system as well as studies of larger sample of wide binary systems hosting massive planets, are needed to better understand the chemical abundance trend observed in HD196067-68.Comment: 9 pages, six figures, three table

Microglial ramification, surveillance and interleukin-1beta release are regulated by the two-pore domain K+ channel THIK-1

Microglia exhibit two modes of motility: they constantly extend and retract their processes to survey the brain, but they also send out targeted processes to envelop sites of tissue damage. We now show that these motility modes differ mechanistically. We identify the two-pore domain channel THIK-1 as the main K+ channel expressed in microglia in situ. THIK-1 is tonically active, and its activity is potentiated by P2Y12 receptors. Inhibiting THIK-1 function pharmacologically or by gene knockout depolarizes microglia, which decreases microglial ramification and thus reduces surveillance, whereas blocking P2Y12 receptors does not affect membrane potential, ramification, or surveillance. In contrast, process outgrowth to damaged tissue requires P2Y12 receptor activation but is unaffected by blocking THIK-1. Block of THIK-1 function also inhibits release of the pro-inflammatory cytokine interleukin-1β from activated microglia, consistent with K+ loss being needed for inflammasome assembly. Thus, microglial immune surveillance and cytokine release require THIK-1 channel activity

Methane fluxes from tropical coastal lagoons surrounded by mangroves, Yucatán, Mexico

Methane concentrations in the water column and emissions to the atmosphere were determined for three tropical coastal lagoons surrounded by mangrove forests on the Yucatán Peninsula, Mexico. Surface water dissolved methane was sampled at different seasons over a period of 2 years in areas representing a wide range of salinities and anthropogenic impacts. The highest surface water methane concentrations (up to 8378 nM) were measured in a polluted canal associated with Terminos Lagoon. In Chelem Lagoon, methane concentrations were typically lower, except in the polluted harbor area (1796 nM). In the relatively pristine Celestún Lagoon, surface water methane concentrations ranged from 41 to 2551 nM. Methane concentrations were negatively correlated with salinity in Celestún, while in Chelem and Terminos high methane concentrations were associated with areas of known pollution inputs, irrespective of salinity. The diffusive methane flux from surface lagoon water to the atmosphere ranged from 0.0023 to 15 mmol CH4 m-2 d-1. Flux chamber measurements revealed that direct methane release as ebullition was up to 3 orders of magnitude greater than measured diffusive flux. Coastal mangrove lagoons may therefore be an important natural source of methane to the atmosphere despite their relatively high salinity. Pollution inputs are likely to substantially enhance this flux. Additional statistically rigorous data collected globally are needed to better consider methane fluxes from mangrove-surrounded coastal areas in response to sea level changes and anthropogenic pollution in order to refine projections of future atmospheric methane budgets

Predicting high risk of exacerbations in bronchiectasis: the E-FACED score

BACKGROUND: Although the FACED score has demonstrated a great prognostic capacity in bronchiectasis, it does not include the number or severity of exacerbations as a separate variable, which is important in the natural history of these patients. OBJECTIVE: Construction and external validation of a new index, the E-FACED, to evaluate the predictive capacity of exacerbations and mortality. METHODS: The new score was constructed on the basis of the complete cohort for the construction of the original FACED score, while the external validation was undertaken with six cohorts from three countries (Brazil, Argentina, and Chile). The main outcome was the number of annual exacerbations/hospitalizations, with all-cause and respiratory-related deaths as the secondary outcomes. A statistical evaluation comprised the relative weight and ideal cut-off point for the number or severity of the exacerbations and was incorporated into the FACED score (E-FACED). The results obtained after the application of FACED and E-FACED were compared in both the cohorts. RESULTS: A total of 1,470 patients with bronchiectasis (819 from the construction cohorts and 651 from the external validation cohorts) were followed up for 5 years after diagnosis. The best cut-off point was at least two exacerbations in the previous year (two additional points), meaning that the E-FACED has nine points of growing severity. E-FACED presented an excellent prognostic capacity for exacerbations (areas under the receiver operating characteristic curve: 0.82 for at least two exacerbations in 1 year and 0.87 for at least one hospitalization in 1 year) that was statistically better than that of the FACED score (0.72 and 0.78, P<0.05, respectively). The predictive capacities for all-cause and respiratory mortality were 0.87 and 0.86, respectively, with both being similar to those of the FACED. CONCLUSION: E-FACED score significantly increases the FACED capacity to predict future yearly exacerbations while maintaining the score’s simplicity and prognostic capacity for death