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Quantum Backreaction on Three-Dimensional Black Holes and Naked Singularities
2016
We analytically investigate backreaction by a quantum scalar field on two rotating Ba\~nados-Teitelboim-Zanelli (BTZ) geometries: that of a black hole and that of a naked singularity. In the former case, we explore the quantum effects on various regions of relevance for a rotating black hole space-time. We find that the quantum effects lead to a growth of both the event horizon and the radius of the ergosphere, and to a reduction of the angular velocity, compared to the unperturbed values. Furthermore, they give rise to the formation of a curvature singularity at the Cauchy horizon and show no evidence of the appearance of a superradiant instability. In the case of a naked singularity, we f…
Feedback on individual academic presentations: exploring Finnish university students’ experiences and preferences
2015
With an increasing emphasis on measuring the outcomes of learning in higher education, assessment is gaining an ever more prominent role in curriculum design and development as well as in instructional practices. In formative assessment, feedback is regarded as a powerful pedagogical tool driving student engagement and deep learning. The efficacy of feedback, however, depends on a multitude of factors. From a learning cultures perspective (James 2014), assessment strives for an appropriate balance between structural constraints and individual agency. To have a better grasp of how feedback functions in practice, it is useful to investigate students’ views and preferences as well as the immed…
Geo-neutrino results with Borexino
2015
International audience; Borexino is a liquid scintillator detector primary designed to observe solar neutrinos. Due to its low background level as well as its position in a nuclear free country, Italy, Borexino is also sensitive to geo-neutrinos. Borexino is leading this interdisciplinary field of neutrino geoscience by studying electron antineutrinos which are emitted from the decay of radioactive isotopes present in the crust and the mantle of the Earth. With 2056 days of data taken between December 2007 and March 2015, Borexino observed 77 antineutrino candidates. If we assume a chondritic Th/U mass ratio of 3.9, the number of geo-neutrino events is found to be 23.7(+6.5) (-5.7)(stat) (+…
El poderoso y su doble. Amis y Amiles en el teatro clásico español
2017
El propósito de este artículo es doble. Por un lado, se pretende estudiar dos muestras de la versión teatral española de la leyenda de Amis y Amiles, representada por La sutil maraña de los dos fieles y parescidos amigos Luis y Alejandro y los sucesos de Alejandro y cómo por su saber vino a ser rey de Egipto (BNE, mss. 15049) y Los pronósticos de Alejandre (BNE, mss. 16064) y su conexión con el capítulo 21 de los Siete Sabios de Roma. El análisis de la estructura métrica de estos dramas pone de manifiesto que debieron componerse durante las dos últimas décadas del siglo XVI. Por otro lado, se intenta profundizar en el contexto educativo del futuro Felipe III para explorar los significados q…
Neglecting the 19th century
2015
The present article examines the historical narrative proposed by modernization theory about the recent Spanish past. Its assumptions and consequences for historical research focused on the 19th century are described in order to understand the lack of intellectual exchange among historians and sociologists in the Spanish academic world. Modernization theory has justified the political consensus that allowed the Spanish transition to democracy and its academic authority has narrowed the scope of historical research about previous democratization processes. Although the paradigm of Spanish backwardness has been refuted by specialists on 19th-century Spain, sociologists, economists and histor…
The high precision measurement of the 144Ce activity in the SOX experiment
2015
International audience; In order to perform a resolutive measurement to clarify the neutrino anomalies and to observe possible short distance neutrino oscillations, the SOX (Short distance neutrino Oscillations with BoreXino) experiment is under construction. In the first phase, a 100 kCi (144)Ce-(144)Pr antineutrino source will be placed under the Borexino detector at the Laboratori Nazionali del Gran Sasso (LNGS), in center of Italy, and the rate measurement of the antineutrino events, observed by the very low radioactive background Borexino detector, will be compared with the high precision (< 1%) activity measurement performed by two calorimeters. The source will be embedded in a 19 mm …
Overview and accomplishments of the Borexino experiment
2015
International audience; The Borexino experiment is running at the Laboratori del Gran Sasso in Italy since 2007. Its technical distinctive feature is the unprecedented ultralow background of the inner scintillating core, which is the basis of the outstanding achievements accumulated by the experiment. In this talk, after recalling the main features of the detector, the impressive solar data gathered so far by the experiment will be summarized, with special emphasis to the most recent and prominent result concerning the detection of the fundamental pp solar neutrino flux, which is the direct probe of the engine mechanism powering our star. Such a milestone measurement puts Borexino in the un…
Emosjonelt arbeid blant frontlinjeansatte : Hvordan opplever og håndterer nav-ansatte det emosjonelle arbeidet de utøver på jobb?
2017
Masteroppgave Sosiologi og sosialt arbeid ME522 - Universitetet i Agder 2017 Formålet med denne oppgaven er å få en forståelse for det emosjonelle arbeidet som frontlinjeansatte på nav utøver. Fokuset er å belyse både hvordan de opplever og hvordan de håndterer ulike situasjoner de kommer opp i. Oppgaven er basert på intervjuer og observasjoner av totalt 13 ansatte på et lokalt nav-kontor som arbeider tett med brukere innenfor ulike avdelinger. Med utgangspunkt i datamaterialet, analyseres innholdet først før det blir drøftet opp mot teori. Teoriene til Erving Goffman og Arlie Hochschild blir brukt bevisst gjennom hele oppgaven for å få frem ulike momenter ved emosjonsarbeidet og selve møte…
Class-B two-photon Fabry–Pérot laser
1998
Abstract We study the stationary operation and stability properties of a class-B two-photon Fabry–Perot laser. We show that, differently from the one-photon laser, the intensity emitted by the two-photon laser is larger in a Fabry–Perot than in a ring cavity. The lasing solution loses stability through a subcritical Hopf bifurcation, as it occurs in the unidirectional ring laser. The stability domain in the parameter space is larger in the Fabry–Perot than in the ring cavity configuration.
Thermal lens spectrometry in biochemical analysis.
1994
The photothermal spectroscopic techniques, with special emphasis on the thermal lens spectrometry (TLS), are introduced to the non-specialist in laser spectroscopy. The following topics are treated on an elementary basis: fundamentals and analytical characteristics, instrumentation, selectivity and multi-wavelength capability, the models describing the signal-concentration relationship, the sensitivity, background noise and limits of detection, the influence of light scattering and flow. Applications related to the fields of clinical and biochemical analysis and organic pollution are given. The thermal lens circular dichroism and the infrared TLS are also briefly outlined.