7,205 research outputs found

    A new method for the spectroscopic identification of stellar non-radial pulsation modes. II. Mode identification of the Delta Scuti star FG Virginis

    Get PDF
    We present a mode identification based on new high-resolution time-series spectra of the non-radially pulsating Delta Scuti star FG~Vir (HD 106384, V = 6.57, A5V). From 2002 February to June a global Delta Scuti Network (DSN) campaign, utilizing high-resolution spectroscopy and simultaneous photometry has been conducted for FG~Vir in order to provide a theoretical pulsation model. In this campaign we have acquired 969 Echelle spectra covering 147 hours at six observatories. The mode identification was carried out by analyzing line profile variations by means of the Fourier parameter fit method, where the observational Fourier parameters across the line are fitted with theoretical values. This method is especially well suited for determining the azimuthal order m of non-radial pulsation modes and thus complementary with the method of Daszynska-Daszkiewicz (2002) which does best at identifying the degree l. 15 frequencies between 9.2 and 33.5 c/d were detected spectroscopically. We determined the azimuthal order m of 12 modes and constrained their harmonic degree l. Only modes of low degree (l <= 4) were detected, most of them having axisymmetric character mainly due to the relatively low projected rotational velocity of FG Vir. The detected non-axisymmetric modes have azimuthal orders between -2 and 1. We derived an inclination of 19 degrees, which implies an equatorial rotational rate of 66 km/s.Comment: 14 pages, 26 figure

    Community health workers at the dawn of a new era: 3. Programme governance

    Get PDF
    Background: Community health workers (CHWs) can play a critical role in primary healthcare and are seen widely as important to achieving the health-related Sustainable Development Goals (SDGs). The COVID-19 pandemic has emphasized the key role of CHWs. Improving how CHW programmes are governed is increasingly recognized as important for achieving universal access to healthcare and other health-related goals. This paper, the third in a series on “Community Health Workers at the Dawn of a New Era”, aims to raise critical questions that decision-makers need to consider for governing CHW programmes, illustrate the options for governance using examples of national CHW programmes, and set out a research agenda for understanding how CHW programmes are governed and how this can be improved. Methods: We draw from a review of the literature as well as from the knowledge and experience of those involved in the planning and management of CHW programmes. Results: Governing comprises the processes and structures through which individuals, groups, programmes, and organizations exercise rights, resolve diferences, and express interests. Because CHW programmes are located between the formal health system and communities, and because they involve a wide range of stakeholders, their governance is complex. In addition, these programmes frequently fall outside of the governance structures of the formal health system or are poorly integrated with it, making governing these programmes more challenging. We discuss the following important questions that decision-makers need to consider in relation to governing CHW programmes: (1) How and where within political structures are policies made for CHW programmes? (2) Who implements decisions regarding CHW programmes and at what levels of government? (3) What laws and regulations are needed to support the programme? (4) How should the programme be adapted across diferent settings or groups within the country or region? Conclusion: The most appropriate and acceptable models for governing CHW programmes depend on communities, on local health systems, and on the political system in which the programme is located. Stakeholders in each setting need to consider what systems are currently in place and how they might be adapted to local needs and systems

    QualitĂ€tsvergleich von Regenbogenforellen aus konventioneller und ökologisch zertifizierter Aufzucht als Voraussetzung fĂŒr eine Verbesserung der WettbewerbsfĂ€higkeit von Bioforellen

    Get PDF
    Die Studie umfasste die Untersuchung der Aufzuchtsbedingungen sowie Futterversuche und vergleichende Untersuchungen zur ProduktqualitĂ€t. Es wurden 2 ökologisch zertifizierte und 3 konventionelle Forellenzuchtbetriebe verglichen. TagesgĂ€nge verschiedener wasserchemischer Parameter an Zu- und Ablauf der Teiche umfassten die Bestimmung von Temperatur, Sauerstoff, pH-Wert, Ammonium-, Nitrit-, Gesamt- und ortho-Phosphatgehalt sowie CSB- und Feststoffgehalt. In zwei Futterversuchen wurden Ökofutter fĂŒr Forellen mit konventionellen Futtern hinsichtlich Wachstum, Futterverwertung und Proteinausnutzung verglichen. Die zwei untersuchten ökologischen Futtermittel zeigten im Vergleich ein schlechteres Protein-/EnergieverhĂ€ltnis, das sich in niedrigeren Rohfettgehalten ausdrĂŒckte. ZusĂ€tzlich wurden futterbedingte Stickstoffexkretionsmuster von Forellen im Tagesgang untersucht. Im Ergebnis zeigte sich, dass die Ökofutter im Vergleich zu den konventionellen Futtern zu einer stĂ€rkeren Umweltbelastung und einem geringerem Wachstum bei schlechterer Futterverwertung fĂŒhrten. Die QualitĂ€tsuntersuchungen der Forellen beinhalteten die Erfassung der biologischen Para-meter, die mikrobiologische und sensorische Beurteilung der Ware, Farb- und Texturmessun-gen, die Bestimmung der chemischen Zusammensetzung einschließlich der RĂŒckstĂ€nde sowie bildverarbeitende Methoden und die Aufnahme des Aromaprofils. Insgesamt waren die ProduktqualitĂ€t und der mikrobiologische Status aller untersuchten Forellen sehr gut. In ihrer chemischen Zusammensetzung unterschieden sich die Fische vor allem im Fettgehalt. Alle ermittelten RĂŒckstandsgehalte lagen weit unter den zulĂ€ssigen Höchstwerten. Ein Zusammenhang zwischen der Aufzuchtsform und der QualitĂ€t konnte nicht festgestellt werden. Bei den Projektergebnissen handelt es sich um eine AbschĂ€tzung der Situation ausgewĂ€hlter Forellenzuchtbetriebe, reprĂ€sentative Aussagen können aus den Ergebnissen nicht abgeleitet werden

    Neutron Irradiation of Mg11B2 : From the Enhancement to the Suppression of Superconducting Properties

    Full text link
    In this letter we present the effect of neutron irradiation up to fluences of 3.9 1019 n/cm2 on the superconducting properties of MgB2. In order to obtain a disorder structure homogeneously distributed, the experiment was carried out on bulk samples prepared with the 11B isotope. Up to fluences of 1018 n/cm2 the critical temperature is slightly diminished (36 K) and the superconducting properties are significantly improved; the upper critical field is increased from 13.5 T to 20.3 T at 12 K and the irreversibility field is doubled at 5 K. For larger neutron fluences the critical temperature is suppressed down to 12 K and the superconducting properties come out strongly degraded.Comment: 13 pages, 4 figures. Submitted to Appl.Phys.Let

    The Interaction of Laser Energy with Ureter Tissues in a Long Term Investigation

    Get PDF
    This study investigates tissue responses after laser irradiation of the rabbit ureter, which serves as an experimental model for rectourogenital fistulae of children. Twenty-five rabbit ureters were irradiated intraluminally by a Nd:YAG laser 1320 nm (2 Watt, 20 seconds and 3 Watt, 8 seconds) via an applicator with radialsymmetrical light distribution. Immediately, 2 weeks, 4 weeks, 8 weeks, and 16 weeks after irradiation, the ureters were X-rayed with contrast solution and prepared for light and transmission electron microscopy. For the parameters employed, no apparent morphological differences could be observed. Immediately, the central laser zone showed a transmural therrnonecrosis prevailed by cellular destruction, condensed ground substance and occlusion of most vascular lumina. Peripheral laser zones displayed urothelial vacuolations. Between 2 and 16 weeks, urothelial regeneration and ingrowth of granulation tissue caused a luminal stenosis or occlusion followed by transformation into scar tissue. In some peripheral laser zones, a hydroureter with marked luminal dilatation developed. We conclude that the ureter is occluded if the expanding force of the growing scar tissue exceeds the hydrostatic pressure of the obstructed urine. A laser occlusion of rectourogenital fistulae will be easier to achieve since fistula occlusion does not entail an obstruction of the urine flow

    Criteria of efficiency for conformal prediction

    Get PDF
    We study optimal conformity measures for various criteria of efficiency of classification in an idealised setting. This leads to an important class of criteria of efficiency that we call probabilistic; it turns out that the most standard criteria of efficiency used in literature on conformal prediction are not probabilistic unless the problem of classification is binary. We consider both unconditional and label-conditional conformal prediction.Comment: 31 page

    Biofisch – QualitĂ€tsvergleich zwischen konventionellen und ökologisch produzierten Forellen

    Get PDF
    Die Studie umfasste die Untersuchung der Aufzuchtsbedingungen sowie Futterversuche und vergleichende Untersuchungen zur ProduktqualitĂ€t an Portionsforellen. Es wurden 2 ökologisch zertifizierte und 3 konventionelle Forellenzuchtbetriebe verglichen. In dieser Arbeit werden nur die Ergebnisse der QualitĂ€tsuntersuchungen wiedergegeben. Die Untersuchungen der Portionsforellen beinhalteten die Erfassung der biologischen Parameter, die mikrobiologische und sensorische Beurteilung der Ware, Farb- und Texturmessungen, die Bestimmung der chemischen Zusammensetzung einschließlich der RĂŒckstĂ€nde sowie bildverarbeitende Methoden und die Aufnahme des Aromaprofils. Insgesamt waren die QualitĂ€t und der mikrobiologische Status aller untersuchten Forellen sehr gut. In ihrer chemischen Zusammensetzung unterschieden sich die Fische vor allem im Fettgehalt. Alle ermittelten RĂŒckstandsgehalte lagen weit unter den zulĂ€ssigen Höchstwerten. Unterschiede zwischen den Aufzuchtsformen wurden nicht gefunden

    Enhanced flux pinning in neutron irradiated MgB2

    Full text link
    We study the effect of neutron irradiation on the critical current density Jc of isotopically pure polycrystalline Mg11B2 samples. For fluences in the range 1017-1018 cm-2, Jc is enhanced and its dependence on magnetic field is significantly improved: we demonstrate that, in this regime, point-like pinning centers are effectively introduced in the system proportionally to the neutron fluence. Instead, for larger fluences, a strong suppression of the critical temperature accompanied by a decrease of both the upper critical field Bc2 and Jc is found.Comment: 13 pages, 3 igure

    Strong friction limit in quantum mechanics: the Quantum Smoluchowski equation

    Full text link
    For a quantum system coupled to a heat bath environment the strong friction limit is studied starting from the exact path integral formulation. Generalizing the classical Smoluchowski limit to low temperatures a time evolution equation for the position distribution is derived and the strong role of quantum fluctuations in this limit is revealed.Comment: 4 pages, PRL in pres
    • 

    corecore