<i>Gaia</i> Data Release 1. Summary of the astrometric, photometric, and survey properties

Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7. Aims. A summary of Gaia DR1 is presented along with illustrations of the scientific quality of the data, followed by a discussion of the limitations due to the preliminary nature of this release. Methods. The raw data collected by Gaia during the first 14 months of the mission have been processed by the Gaia Data Processing and Analysis Consortium (DPAC) and turned into an astrometric and photometric catalogue. Results. Gaia DR1 consists of three components: a primary astrometric data set which contains the positions, parallaxes, and mean proper motions for about 2 million of the brightest stars in common with the HIPPARCOS and Tycho-2 catalogues – a realisation of the Tycho-Gaia Astrometric Solution (TGAS) – and a secondary astrometric data set containing the positions for an additional 1.1 billion sources. The second component is the photometric data set, consisting of mean G-band magnitudes for all sources. The G-band light curves and the characteristics of ∼3000 Cepheid and RR-Lyrae stars, observed at high cadence around the south ecliptic pole, form the third component. For the primary astrometric data set the typical uncertainty is about 0.3 mas for the positions and parallaxes, and about 1 mas yr−1 for the proper motions. A systematic component of ∼0.3 mas should be added to the parallax uncertainties. For the subset of ∼94 000 HIPPARCOS stars in the primary data set, the proper motions are much more precise at about 0.06 mas yr−1. For the secondary astrometric data set, the typical uncertainty of the positions is ∼10 mas. The median uncertainties on the mean G-band magnitudes range from the mmag level to ∼0.03 mag over the magnitude range 5 to 20.7. Conclusions. Gaia DR1 is an important milestone ahead of the next Gaia data release, which will feature five-parameter astrometry for all sources. Extensive validation shows that Gaia DR1 represents a major advance in the mapping of the heavens and the availability of basic stellar data that underpin observational astrophysics. Nevertheless, the very preliminary nature of this first Gaia data release does lead to a number of important limitations to the data quality which should be carefully considered before drawing conclusions from the data

Gaia Data Release 1: Testing parallaxes with local Cepheids and RR Lyrae stars

Context. Parallaxes for 331 classical Cepheids, 31 Type II Cepheids, and 364 RR Lyrae stars in common between Gaia and the Hipparcos and Tycho-2 catalogues are published in Gaia Data Release 1 (DR1) as part of the Tycho-Gaia Astrometric Solution (TGAS). Aims. In order to test these first parallax measurements of the primary standard candles of the cosmological distance ladder, which involve astrometry collected by Gaia during the initial 14 months of science operation, we compared them with literature estimates and derived new period-luminosity (PL), period-Wesenheit (PW) relations for classical and Type II Cepheids and infrared PL, PL-metallicity (PLZ), and optical luminosity-metallicity (M V -[Fe/H]) relations for the RR Lyrae stars, with zero points based on TGAS. Methods. Classical Cepheids were carefully selected in order to discard known or suspected binary systems. The final sample comprises 102 fundamental mode pulsators with periods ranging from 1.68 to 51.66 days (of which 33 with σ Ω /Ω < 0.5). The Type II Cepheids include a total of 26 W Virginis and BL Herculis stars spanning the period range from 1.16 to 30.00 days (of which only 7 with σ Ω /Ω < 0.5). The RR Lyrae stars include 200 sources with pulsation period ranging from 0.27 to 0.80 days (of which 112 with σ Ω /Ω < 0.5). The new relations were computed using multi-band (V,I,J,K s ) photometry and spectroscopic metal abundances available in the literature, and by applying three alternative approaches: (i) linear least-squares fitting of the absolute magnitudes inferred from direct transformation of the TGAS parallaxes; (ii) adopting astrometry-based luminosities; and (iii) using a Bayesian fitting approach. The last two methods work in parallax space where parallaxes are used directly, thus maintaining symmetrical errors and allowing negative parallaxes to be used. The TGAS-based PL,PW,PLZ, and M V - [Fe/H] relations are discussed by comparing the distance to the Large Magellanic Cloud provided by different types of pulsating stars and alternative fitting methods. Results. Good agreement is found from direct comparison of the parallaxes of RR Lyrae stars for which both TGAS and HST measurements are available. Similarly, very good agreement is found between the TGAS values and the parallaxes inferred from the absolute magnitudes of Cepheids and RR Lyrae stars analysed with the Baade-Wesselink method. TGAS values also compare favourably with the parallaxes inferred by theoretical model fitting of the multi-band light curves for two of the three classical Cepheids and one RR Lyrae star, which were analysed with this technique in our samples. The K-band PL relations show the significant improvement of the TGAS parallaxes for Cepheids and RR Lyrae stars with respect to the Hipparcos measurements. This is particularly true for the RR Lyrae stars for which improvement in quality and statistics is impressive. Conclusions. TGAS parallaxes bring a significant added value to the previous Hipparcos estimates. The relations presented in this paper represent the first Gaia-calibrated relations and form a work-in-progress milestone report in the wait for Gaia-only parallaxes of which a first solution will become available with Gaia Data Release 2 (DR2) in 2018. © ESO, 2017

Luminescence of ZnGa2Î4 AND ZnAl2Î4 spinels doped with Eu3+AND Tb3+ ions

Spinel type mono-phase the ZnGa2O4 and ZnAl2O4 compounds doped with Eu3+ and Tb3+ ions were obtained using two methods: solid phase reactions and deposition from chemical solutions. The luminescent analysis of the materials shows that the rare earth ions are localised at the defect sites (regions) of the crystallite (grain) boundaries. The emission spectra of the samples with europium are characterized by an intense emission in red region due to the 5D0 → 7F1,2 transitions of Eu3+ ions, whereas, in the case of terbium, the highest intensity corresponds to the green emission due to the 5D4 → 7F5 transitions of Tb3+ ions. The intensities of the intra-shell emission of the Eu3+ and Tb3+ ions in comparison with luminescence intensity of the chromium impurity traces (residual small amount of the Cr3+ ions) show that the materials doped with transition metals are more promising for development of phosphors based on oxide spinels than the materials doped with rare-earth elements

Muscle flaps – an alternative for decortication or resection to solve the residual space in impaired patients

Universitatea de Medicină și Farmacie „Victor Babeș”, Clinica I Chirurgie, Spitalul Clinic Judeţean de Urgenţă „Pius Brinzeu”, Clinica de Chirurgie Toracică, Spitalul Clinic Municipal de Urgenţă, Timișoara, România, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Decorticările sau rezecțiile pulmonare reprezintă tratamentul chirurgical obişnuit în cazul pacienților cu empiem sau abcese pulmonare cronice. Pentru un număr redus de pacienți cu comorbidități severe asociate sau disfuncții respiratorii aceste operații nu sunt indicate. Am analizat eficiența lambourilor musculare pentru a corecta cavitățile reziduale. Material și metode: Am studiat pacienți cu scor de risc ASA >3, cu FEV si FVC<40, clasa NYHA mai mare sau egală cu II. Am inclus în studiu pacienți cu empiem (1caz), aspergiliom (8 cazuri), abces pulmonar cronic (1 caz) .Am folosit diverse lambouri musculare pentru a umple cavitățile. Pentru pacienții cu aspergilom am practicat toracotomie, cavernotomie, excizia micetomului, sutura fistulei. Am folosit lambouri din pectoralul mare (2), muşchii intercostali (4) şi dorsal mare (2). Pentru pacienții cu supurații cronice pulmonare am folosit dorsal mare, iar pentru empiem am asociat şi muşchi pectoral mare, trapez şi intercostal cu toracoplastie. Rezultate: Evoluția imediată a fost favorabilă în toate cazurile cu excepția unuia care a necesitat reintervenție pentru sângerare. Un pacient a dezvoltat serom. În toate cazurile, viabilitatea lamboului nu a fost afectată. Nu s-au inregistrat decese. Concluzii: Scopul acestor intervenții a fost sa eliminăm spațiile libere din pleură sau plămân. Pentru pacienții tarați, decorticările şi rezecțiile sunt operații riscante, această nouă abordare fiind benefică. Evoluția favorabilă, morbiditatea minimă după folosirea lambourilor musculare justifică deplin acest procedeu. Chiar dacă numărul mic de cazuri în care am practicat acest tip de operație ne limitează pentru moment spectrul de experiență, rezultatele pozitive sunt încurajatoare.Introduction: The surgical treatment of residual space for patients with empyema or chronic lung abscess is in most cases decortication or lung resection. For a limited number of patients with severe comorbidities or respiratory dysfunction these procedures are prohibited. We analyzed the efficiency of muscle flaps to solve the residual cavities these patients. Material and methods: We studied patients with ASA risk > 3, with FEV and FVC < 40%, NYHA II or more. Patients with empyema (1 case), aspergilloma (8 cases), chronic lung abscess (1 case) were included in the study. Different types of muscle flaps were used to fill the cavities. For patients with aspergilloma we performed thoracotomy, cavernotomy, excision of the micetoma, fistulae suture; muscles used: pectoris major – 2, intercostal – 4 and latissimus dorsi – 2. For the patient with chronic suppuration of the lung we used latissimus, and for the empyema we associated pectoris major, trapezius and intercostal muscle with thoracoplasty. Results: The immediate outcome was favorable in all cases except one who required exploration for bleeding. One patient developed wound seroma. In all cases the viability of the transposed muscle was not affected. We recorded no mortality. Conclusions: The aim of surgery is to eliminate all empty space in the pleura or lung. For impaired patients decortication or resection are very risky, thus new approach was needed. The good outcome, minimal morbidity after using muscle flaps, fully justify their use. The low number of patients limits our experience, but the good results are encouraging

Presentation of Graves’ orbitopathy within European Group On Graves’ Orbitopathy (EUGOGO) centres from 2012 to 2019 (PREGO III)

Background Graves orbitopathy (GO) is subject to epidemiological and care-related changes. Aim of the survey was to identify trends in presentation of GO to the European Group On Graves’ Orbitopathy (EUGOGO) tertiary referral centres and initial management over time. Methods Prospective observational multicentre study. All new referrals with diagnosis of GO within September–December 2019 were included. Clinical and demographic characteristics, referral timelines and initial therapeutic decisions were recorded. Data were compared with a similar EUGOGO survey performed in 2012. Results Besides age (mean age: 50.5±13 years vs 47.7±14 years; p 0.007), demographic characteristics of 432 patients studied in 2019 were similar to those in 2012. In 2019, there was a decrease of severe cases (9.8% vs 14.9; p&lt;0.001), but no significant change in proportion of active cases (41.3% vs 36.6%; p 0.217). After first diagnosis of GO, median referral time to an EUGOGO tertiary centre was shorter (2 (0–350) vs 6 (0–552) months; p&lt;0.001) in 2019. At the time of first visit, more patients were already on antithyroid medications (80.2% vs 45.0%; p&lt;0.001) or selenium (22.3% vs 3.0%; p&lt;0.001). In 2019, the initial management plans for GO were similar to 2012, except for lid surgery (2.4% vs 13.9%; p&lt;0.001) and prescription of selenium (28.5% vs 21.0%; p 0.027). Conclusion GO patients are referred to tertiary EUGOGO centres in a less severe stage of the disease than before. We speculate that this might be linked to a broader awareness of the disease and faster and adequate delivered treatment

Guided mode lasing in ZnO nanorod structures

Access full text - https://doi.org/10.1016/j.spmi.2009.04.008Quasi-two-dimensional arrays of nearly parallel hexagonal ZnO nanorods and a three-dimensional cylindrical microstructure consisting of ZnO nanorods have been grown by low pressure chemical vapor deposition (CVD) and carbothermal evaporation technologies, respectively. The technology ensures high optical quality of the produced nanostructures so as to act as a gain medium for stimulated emission in the ultraviolet spectral region in combination with high quality factor laser resonators. Multiple sharp lasing peaks were realized from the produced structures under nanosecond pulse optical excitation. The lasing peaks display successive onset and saturation with increasing excitation power density in accordance with the lasing behavior of guided modes in ZnO nanorods. The produced structures are expected to find applications in integrated nanoscale optoelectronics, photonics, and sensor technologies