180 research outputs found

    XSHOOTER spectroscopy of the enigmatic planetary nebula Lin49 in the Small Magellanic Cloud

    Get PDF
    We performed a detailed spectroscopic analysis of the fullerene C60-containing planetary nebula (PN) Lin49 in the Small Magellanic Cloud (SMC) using XSHOOTER at the European Southern Observatory Very Large Telescope and the Spitzer/Infrared Spectrograph instruments. We derived nebular abundances for nine elements. We used TLUSTY to derive photospheric parameters for the central star. Lin49 is C-rich and metal-deficient PN (Z ∌ 0.0006). The nebular abundances are in good agreement with asymptotic giant branch nucleosynthesis models for stars with initial mass 1.25 M⊙ and metallicity Z = 0.001. Using the TLUSTY synthetic spectrum of the central star to define the heating and ionizing source, we constructed the photoionization model with CLOUDY that matches the observed spectral energy distribution (SED) and the line fluxes in the UV to far-IR wavelength ranges simultaneously. We could not fit the ∌1–5 ÎŒm SED using a model with 0.005–0.1-ÎŒm-sized graphite grains and a constant hydrogen density shell owing to the prominent near-IR excess, while at other wavelengths the model fits the observed values reasonably well. We argue that the near-IR excess might indicate either (1) the presence of very small particles in the form of small carbon clusters, small graphite sheets, or fullerene precursors, or (2) the presence of a high-density structure surrounding the central star. We found that SMC C60 PNe show a near-IR excess component to lesser or greater degree. This suggests that these C60 PNe might maintain a structure nearby their central star

    Di[2,6-bis(5-phenylpyrazol-3-yl)pyridine]Co(II): an old coordination mode fora novel supramolecular assembly

    Get PDF
    CoCl2 was treated with 1, 2, and 6 eq. of 2,6-bis(5-phenylpyrazol-3-yl)pyridine (H2L) yielding respectively the monosubstituted [Co(H2L)Cl2], the disubstituted [Co(H2L)2][PF6]2, and a supramolecular assembly formed by a central disubstituted octahedral complex and four more hydrogen bonded peripheral ligands, [{Co(H2L)2}(H2L)4][PF6]2, as illustrated by X-ray crystal structure analysis

    Submillimetre Transient Science in the Next Decade

    Get PDF
    White paper from the EAO Submillimetre Futures Meeting, 20-23 May 2019, Nanjing, ChinaThis white paper gives a brief summary of the time domain science that has been performed with the JCMT in recent years and highlights the opportunities for continuing work in this field over the next decade. The main focus of this document is the JCMT Transient Survey, a large program initiated in 2015 to measure the frequency and amplitude of variability events associated with protostars in nearby star-forming regions. After summarising the major accomplishments so far, an outline is given for extensions to the current survey, featuring a discussion on what will be possible with the new 850 micron camera that is expected to be installed in late 2022. We also discuss possible applications of submillimetre monitoring to active galactic nuclei, X-ray binaries, asymptotic giant branch stars, and flare stars.Science and Technology Facilities Counci

    The cardiac sodium channel displays differential distribution in the conduction system and transmural heterogeneity in the murine ventricular myocardium

    Get PDF
    Cardiac sodium channels are responsible for conduction in the normal and diseased heart. We aimed to investigate regional and transmural distribution of sodium channel expression and function in the myocardium. Sodium channel Scn5a mRNA and Na(v)1.5 protein distribution was investigated in adult and embryonic mouse heart through immunohistochemistry and in situ hybridization. Functional sodium channel availability in subepicardial and subendocardial myocytes was assessed using patch-clamp technique. Adult and embryonic (ED14.5) mouse heart sections showed low expression of Na(v)1.5 in the HCN4-positive sinoatrial and atrioventricular nodes. In contrast, high expression levels of Na(v)1.5 were observed in the HCN4-positive and Cx43-negative AV or His bundle, bundle branches and Purkinje fibers. In both ventricles, a transmural gradient was observed, with a low Na(v)1.5 labeling intensity in the subepicardium as compared to the subendocardium. Similar Scn5a mRNA expression patterns were observed on in situ hybridization of embryonic and adult tissue. Maximal action potential upstroke velocity was significantly lower in subepicardial myocytes (mean +/- SEM 309 +/- 32 V/s; n = 14) compared to subendocardial myocytes (394 +/- 32 V/s; n = 11; P < 0.05), indicating decreased sodium channel availability in subepicardium compared to subendocardium. Scn5a and Na(v)1.5 show heterogeneous distribution patterns within the cardiac conduction system and across the ventricular wall. This differential distribution of the cardiac sodium channel may have profound consequences for conduction disease phenotypes and arrhythmogenesis in the setting of sodium channel diseas

    The SN 2023ixf Progenitor in M101: II. Properties

    Full text link
    We follow our first paper with an analysis of the ensemble of the extensive pre-explosion ground- and space-based infrared observations of the red supergiant (RSG) progenitor candidate for the nearby core-collapse supernova SN 2023ixf in Messier 101, together with optical data prior to explosion obtained with the Hubble Space Telescope (HST). We have confirmed the association of the progenitor candidate with the SN, as well as constrained the metallicity at the SN site, based on SN observations with instruments at Gemini-North. The internal host extinction to the SN has also been confirmed from a high-resolution Keck spectrum. We fit the observed spectral energy distribution (SED) for the star, accounting for its intrinsic variability, with dust radiative-transfer modeling, which assume a silicate-rich dust shell ahead of the underlying stellar photosphere. The star is heavily dust-obscured, likely the dustiest progenitor candidate yet encountered. We found maximum-likelihood estimates of the star's effective temperature and luminosity of 3450 K and 9.3e4 L_Sun, with 68% credible intervals of 2370--3700 K and (7.6--10.8)e4 L_sun. The candidate may have a Galactic RSG analog, IRC -10414, with a strikingly similar SED and luminosity. Via comparison with single-star evolutionary models we have constrained the initial mass of the progenitor candidate from 12 M_sun to as high as 15 M_sun. We have had available to us an extraordinary view of the SN 2023ixf progenitor candidate, which should be further followed up in future years with HST and the James Webb Space Telescope.Comment: 29 pages, submitted to AAS Journal

    ĐžŃĐŸĐ±Đ”ĐœĐœĐŸŃŃ‚Đž ĐșĐŸĐœŃ„Đ»ĐžĐșŃ‚ĐŸĐłĐ”ĐœĐœŃ‹Ń… Đ·ĐŸĐœ у Đ±ĐŸĐ»ŃŒĐœŃ‹Ń… ĐœĐ”ĐČŃ€ĐŸŃ‚ĐžŃ‡Đ”ŃĐșĐžĐŒĐž Ń€Đ°ŃŃŃ‚Ń€ĐŸĐčстĐČĐ°ĐŒĐž Đ¶Đ”ĐœŃ‰ĐžĐœ

    Get PDF
    ĐŸŃ€Đ”ĐŽŃŃ‚Đ°ĐČĐ»Đ”ĐœŃ‹ ĐŽĐ°ĐœĐœŃ‹Đ” ĐŸ разлОчОО ĐșĐŸĐœŃ„Đ»ĐžĐșŃ‚ĐŸĐłĐ”ĐœĐœŃ‹Ń… Đ·ĐŸĐœ у Đ¶Đ”ĐœŃ‰ĐžĐœ Đž ĐŒŃƒĐ¶Ń‡ĐžĐœ, страЮающох ĐœĐ”ĐČŃ€ĐŸŃ‚ĐžŃ‡Đ”ŃĐșĐžĐŒĐž Ń€Đ°ŃŃŃ‚Ń€ĐŸĐčстĐČĐ°ĐŒĐž. ĐŸĐŸĐșĐ°Đ·Đ°ĐœĐŸ, Ń‡Ń‚ĐŸ ĐČыяĐČĐ»Đ”ĐœĐœŃ‹Đ” ĐŸŃĐŸĐ±Đ”ĐœĐœĐŸŃŃ‚Đž ĐœĐ”ĐŸĐ±Ń…ĐŸĐŽĐžĐŒĐŸ учотыĐČать ĐČ ĐŽĐžĐ°ĐłĐœĐŸŃŃ‚ĐžĐșĐ” Đž ĐżŃĐžŃ…ĐŸŃ‚Đ”Ń€Đ°ĐżĐžĐž ĐœĐ”ĐČŃ€ĐŸŃ‚ĐžŃ‡Đ”ŃĐșох Ń€Đ°ŃŃŃ‚Ń€ĐŸĐčстĐČ.The authors report the data about the differences in conflectogenic zones among women and men with neurotic disorders. It was shown that the revealed peculiarities should be taken into consideration in diagnosis and psychotherapy of neurotic disorders

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

    Get PDF
    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    FEFI : finding education for female inmates

    Get PDF
    Within the framework of the multilateral EU-project "Finding Education for Female Inmates" (FEFI), ten partners from eight European countries cooperated on the subject of formal and informal education for adolescent and adult women in prison. Women in prison are a particularly underrepresented group due to their small number (3 to 7%) of the total prison population in all of the partners’ countries . The project aimed to improve and increase participation in lifelong learning by female prisoners who are an integral component of a vulnerable and disadvantaged group - a socially stigmatized group, as well as prisoners and as women.peer-reviewe

    A dusty veil shading Betelgeuse during its Great Dimming

    Get PDF
    This is the author accepted manuscript. The final version is available from Springer Nature via the DOI in this record.Data availability: Raw data were generated at the ESO under programs 0102.D-0240(A), 0102.D-0240(D), 104.20UZ and 104.20V6.004. Derived data that support the findings of this study are available at the Centre de DonnĂ©es Astronomiques de Strasbourg (CDS) via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/other/Nat (for the VLT/SPHERE–ZIMPOL images) and at the Optical Interferometry Database (OiDB; for the VLTI/GRAVITY and VLT/SPHERE–IRDIS SAM observations). Source data are provided with this paper.The SPHERE and GRAVITY pipelines are available on the ESO website: http://www.eso.org/sci/software/ pipelines/index.html. The RADMC3D code is publicly available online: https://github.com/dullemond/ radmc3d-2.0Code availability: The SPHERE and GRAVITY pipelines are available on the ESO website (http://www.eso.org/sci/software/pipelines/index.html). The PyRAF implementation of the Richardson–Lucy deconvolution algorithm is publicly available at https://astroconda.readthedocs.io/en/latest/. The RADMC3D code is publicly available at https://github.com/dullemond/radmc3d-2.0.Red supergiants represent the most common final stage of the evolution of stars with initial masses between 8 and 30-35 times the mass of the Sun. During this phase of lifetime lasting ≈ 105 yrs, they experience substantial mass loss of unknown mechanism. This mass loss can affect their evolutionary path, collapse, future supernova light curve, and ultimate fate as a neutron star or a black hole. From November 2019 to March 2020, the second closest red supergiant (RSG, 222+48 −34 pc) Betelgeuse experienced a historic dimming of its visible brightness, witnessed worldwide. Usually between 0.1 and 1.0 mag, it went down to 1.614±0.008 mag around 7-13 February 2020. Here we report high angular resolution observations showing that the southern hemisphere of the star was ten times darker than usual in the visible. Observations and modeling support the scenario of a dust clump recently formed in the vicinity of the star due to a local temperature decrease in a cool patch appearing on the photosphere. The directly imaged brightness variations of Betelgeuse evolved on a timescale of weeks. This event suggests that an inhomogeneous component of red supergiant mass loss is linked to a very contrasted and rapidly changing photosphere.European Research Council (ERC)European Union Horizon 2020Foundation FlandersKU LeuvenNAS
    • 

    corecore