197 research outputs found

    One-step synthesis of pyridines and dihydropyridines in a continuous flow microwave reactor

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    The Bohlmann–Rahtz pyridine synthesis and the Hantzsch dihydropyridine synthesis can be carried out in a microwave flow reactor or using a conductive heating flow platform for the continuous processing of material. In the Bohlmann–Rahtz reaction, the use of a Brønsted acid catalyst allows Michael addition and cyclodehydration to be carried out in a single step without isolation of intermediates to give the corresponding trisubstituted pyridine as a single regioisomer in good yield. Furthermore, 3-substituted propargyl aldehydes undergo Hantzsch dihydropyridine synthesis in preference to Bohlmann–Rahtz reaction in a very high yielding process that is readily transferred to continuous flow processing

    Plunging ranula in children: case report and literature review

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    Few cases of plunging ranulas (PRs) occur during childhood and the lesions are frequently misdiagnosed. Here, a PR in a child is reported along with a literature review. A seven-year-old female complaining of swelling in the midline neck, left-submandibular region, was evaluated. No oral cavity or major salivary glands abnormalities were detected. On palpation a soft, painless, and fluid-containing mass was observed. The suspicion PR was performed by ultrasound. The diagnosis was confirmed with a histopathological examination. The lesion was removed with a cervical approach, without recurrence. PR is an uncommon condition in children under 10 years of age. Differential diagnosis depends on clinical examination and ultrasonography. A computed tomography-scan and magnetic resonance imaging can be performed if the diagnosis remains uncertain. In pediatrics, the key to success of the treatment may rely on the radical excision of the cyst and sublingual gland, via an intraoral or submandibular approach

    The population of hot subdwarf stars studied with Gaia I. The catalogue of known hot subdwarf stars

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    In preparation for the upcoming all-sky data releases of the Gaia mission we compiled a catalogue of known hot subdwarf stars and candidates drawn from the literature and yet unpublished databases. The catalogue contains 5613 unique sources and provides multi-band photometry from the ultraviolet to the far infrared, ground based proper motions, classifications based on spectroscopy and colours, published atmospheric parameters, radial velocities and light curve variability information. Using several different techniques we removed outliers and misclassified objects. By matching this catalogue with astrometric and photometric data from the Gaia mission, we will develop selection criteria to construct a homogeneous, magnitude-limited all-sky catalogue of hot subdwarf stars based on Gaia data.Comment: 11 pages, A&A accepte

    When flux standards go wild: white dwarfs in the age of Kepler

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    White dwarf stars have been used as flux standards for decades, thanks to their staid simplicity. We have empirically tested their photometric stability by analyzing the light curves of 398 high-probability candidates and spectroscopically confirmed white dwarfs observed during the original Kepler mission and later with K2 Campaigns 0-8. We find that the vast majority (>97 per cent) of non-pulsating and apparently isolated white dwarfs are stable to better than 1 per cent in the Kepler bandpass on 1-hr to 10-d timescales, confirming that these stellar remnants are useful flux standards. From the cases that do exhibit significant variability, we caution that binarity, magnetism, and pulsations are three important attributes to rule out when establishing white dwarfs as flux standards, especially those hotter than 30,000 K.Comment: Accepted for publication in MNRAS; 7 pages, 4 figures, 2 table

    The effect of vestibular stimulation on motor functions of children with cerebral palsy

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    Background: Cerebral palsy (CP) has been defined as a nonprogressive disease of movement and posture development. Physical therapy techniques use different forms of sensory stimulation to improve neuromotor development. Aim: The aim of this study was to assess the efficacy of a vestibular stimulation training in improving motor functions in cerebral palsy. Population: Fourteen children with CP were randomly separated into two different groups in a cross-over trial. Methods: Over a period of 10 weeks, each group performed 10 sessions of 50 min of neurodevelopmental treatment (NDT) and 10 sessions of vestibular training (VR). Children were evaluated with the Gross Motor Function Measurement-88 scale, the Goal Attainment Scale and the root mean square of head accelerations. Results: A significant improvement in the GAS-score (p =.003) was noted after NDT+VR. Conclusions: Vestibular stimulation integrated with NDT proved to be an effective complementary strategy for facilitating motor functioning

    An independent test of the photometric selection of white dwarf candidates using LAMOST DR3

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    In Gentile Fusillo et al. (2015) we developed a selection method for white dwarf candidates which makes use of photometry, colours and proper motions to calculate a probability of being a white dwarf (Pwd). The application of our method to the Sloan Digital Sky Survey (SDSS) data release 10 resulted in nearly 66,000 photometrically selected objects with a derived Pwd, approximately 21000 of which are high confidence white dwarf candidates. Here we present an independent test of our selection method based on a sample of spectroscopically confirmed white dwarfs from the LAMOST (Large Sky Area Multi-Fiber Spectroscopic Telescope) survey. We do this by cross matching all our ∼\sim66,000 SDSS photometric white dwarf candidates with the over 4 million spectra available in the third data release of LAMOST. This results in 1673 white dwarf candidates with no previous SDSS spectroscopy, but with available LAMOST spectra. Among these objects we identify 309 genuine white dwarfs. We find that our Pwd can efficiently discriminate between confirmed LAMOST white dwarfs and contaminants. Our white dwarf candidate selection method can be applied to any multi-band photometric survey and in this work we conclusively confirm its reliability in selecting white dwarfs without recourse to spectroscopy. We also discuss the spectroscopic completeness of white dwarfs in LAMOST, as well as deriving effective temperatures, surface gravities and masses for the hydrogen-rich atmosphere white dwarfs in the newly identified LAMOST sample.Comment: 10 pages, 7 figures. Accepted for publication in MNRAS. The full catalogue presented in table 4 is available at http://www2.warwick.ac.uk/fac/sci/physics/research/astro/catalogues/SDSS_WD_candidates_with_LAMOST_spectra.cs

    The vaccination registry of the local health company (ASL) Roma 4

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    Abstract Issue The regional vaccination of Lazio (AVR) and the ASL vaccination registries(AVA) that feed it, have had to adapt to the directions of national vaccination registry. The ASL Roma 4 added other implementations. Description of the Problem L'AVA must, first of all, allow easy search of subjects, defaulters and vaccination coverage for various filters but it can also facilitate the recording and analysis activity. Results The provision of barcodes allows the prompt search of subjects, the check of tax code and AIC codes of vaccines. The digital signature of the privacy and consent forms and anamnesis, taken from the "Guide to contraindications to vaccinations" directly available, allows the elimination of the paper. The possibility to go directly to AVR allows the registration of vaccinations made in other ASL. In addition, the AVA allows the compilation of the adverse event reporting form and vaccine management. The link with the portal on the ASL website allows users to download the vaccination certificate. Important is the possibility to send SMS before vaccination deadlines or appointments. The SMART-SMS allows sending videos or photos and manage a short link (http://tiny.cc/XXX) to an information page on ASL website, as well as user response SMS, that can also directly change appointments. Lessons The dematerialization of the forms leds to a greater compliance with the procedures, a more accurate anamnesis and the streamling of the vaccination session, the SMS bring greater compliance of users and an increase in vaccination coverage. The use of mobile analytics tools allows monitoring of vaccination campaigns. Key messages The dematerialization of the forms in the vaccination registry leds to a greater compliance with the procedures, a more accurate anamnesis and the streamling of the vaccination session. The ability to send SMS through the vaccination registry brings greater compliance of users and an increase in vaccination coverage
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