RFQ-cooler for low-energy radioactive ions at ISOLDE

A radio frequency ion cooler and buncher project at the CERN-ISOLDE facility is presented. Monte Carlo simulations, based on the ion mobility concept will be discussed. Future options for the facility are outlined

Zaoyang chondrite cooling history from pyroxene Fe(2+)-Mg intracrystalline ordering and exolutions

The Zaoyang ordinary chondrite fell as a single 14.15-kg mass in Hubey province (China) in October 1984 and was classified as a non-brecciated H5 chondrite, shock facies b. Cooling rate in pyroxenes can be calculated down to about 1000 C by using fine textures and at still lower temperatures (700 to 200 C) by intracrystalline ordering processes. The crystal chemistry of clinopyroxene and orthopyroxene from the matrix of the H5 Zaoyang chondrite has been investigated by X-ray structure refinement and detailed microprobe analysis. By comparison with terrestrial pyroxenes cell and polyhedral volumes in clino- and orthopyroxenes show a low crystallization pressure. Fe(2+) and Mg are rather disordered in M1 and M2 sites of clino- and orthopyroxenes; the closure temperatures of the exchange reaction are 600 and 512 C respectively, which is consistent with a quite fast cooling rate, estimated of the order of one degree per day. The closure temperature for the intercrystalline Ca-Mg exchange reaction for clino- and orthopyroxene showing clinopyroxene lamellae about 10 microns thick. Kinetic evaluations based on the thickness of exolved lamellae give a cooling rate of not more than a few degrees per 10(exp 4) years. The different cooling rates obtained from Fe(2+)-Mg intracrystalline partitioning and exolution lamellae suggest an initial episode of slow cooling at 900 C, followed by faster cooling at temperatures of 600-500 C at low pressure conditions. The most probable scenario of the meteorite history seems that the exolved orthopyroxene entered the parental chondrite body after exolution had taken place at high temperature. Subsequent fast cooling occurred at low temperature after the formation of the body

TERREMOTI NELL’OMBRA: UN EVENTO CALABRESE NASCOSTO DAL GRANDE TERREMOTO DEL 1915

L’occorrenza di un terremoto distruttivo ha numerose implicazioni, sia di tipo fisico (modifica del campo di stress tettonico) che di tipo storico culturale. Nella storia sismica italiana l’occorrenza di forti terremoti ha generato spesso un aumento dell’attenzione verso questo fenomeno, ed è direttamente correlabile con alcune iniziative che hanno costituito la stessa tradizione storico-sismologica italiana, quali - ad esempio - la redazioni di importanti compilazioni sismologiche, (Giannozzo Manetti e Marcello Bonito, rispettivamente dopo i terremoti del 1456 e del 1688), o la nascita del servizio geodinamico italiano (all’indomani del terremoto ligure del 1887). Tuttavia i terremoti distruttivi hanno anche un effetto di ‘oscuramento’ nella tradizione storica di eventi meno forti, prossimi nello spazio (ma non necessariamente) e soprattutto nel tempo. Diversi casi storici sono stati segnalati da lavori recenti (Camassi e Castelli, 2005), e molti altri sono probabilmente ancora da ‘scoprire’. Nel presente lavoro si illustra un caso di questo genere, che ha la particolarità di verificarsi in tempi molto recenti, immediatamente a ridosso del grande terremoto della Marsica del 1915. Il terremoto colpisce la Calabria Settentrionale, a nord-ovest di Cosenza, e pur non modificando in modo significativo il quadro di conoscenze sulla sismicità dell’area, relativamente ‘ricco’, rappresenta comunque un caso significativo e uno spunto di riflessione importante sul tema della completezza storica delle informazioni sismologiche

Social media and nurse education: an integrative reviewof the literature

Introduction. The exponential advance of social media has touched all areas of society, no exception for the professional and personal lives of healthcare people. The issue to be considered is not whether or not social media are being used, but how they are used. The line between proper and improper use, and even abuse, of social media is a subtle one. Thus, the key issue is to be aware of the tool that is being used and this should be supported with suitable training for healthcare professionals and, at an even earlier stage, for students at healthcare training institutions during their studies. Objective. To describe, through an integrative review of the literature, the use of social media by teachers and students during teaching activity and practical training courses. Materials and methods. An integrative review of the literature was conducted in October 2014. The literature search was performed by consulting the main biomedical databases: PubMed, CINAHL and Embase. Results. The literature search brought up a total of 854 citations. 804 abstracts were excluded as they were not relevant. Of the remaining 50, 31 were excluded for not meeting the general criteria and, hence, only 19 articles were included. Two aspects emerged from the works selected: the use and potential of social media in nursing education and the ethical and professional implications of their use. Conclusions. The analysis of the literature reveals two areas for further investigation: evaluating the level of moral awareness in nursing education with regards to the use of Web 2.0 communication tools and implementing teaching methods to promote the construction and development of moral reasoning in professionals

The Real Scalar Field Equation for Nariai Black Hole in the 5D Schwarzschild-de Sitter Black String Space

The Nariai black hole, whose two horizons are lying close to each other, is an extreme and important case in the research of black hole. In this paper we study the evolution of a massless scalar field scattered around in 5D Schwarzschild-de Sitter black string space. Using the method shown by Brevik and Simonsen (2001) we solve the scalar field equation as a boundary value problem, where real boundary condition is employed. Then with convenient replacement of the 5D continuous potential by square barrier, the reflection and transmission coefficients ($R, T$) are obtained. At last, we also compare the coefficients with usual 4D counterpart.Comment: 10 pages,6 figures.To appear in Int. J. Mod. Phys.

Survival analysis with functions of mis-measured covariate histories: the case of chronic air pollution exposure in relation to mortality in the Nurses\u27 Health Study

Environmental epidemiologists are often interested in estimating the effect of functions of time-varying exposure histories, such as the 12-month moving average, in relation to chronic disease incidence or mortality. The individual exposure measurements that comprise such an exposure history are usually mis-measured, at least moderately, and, often, more substantially. To obtain unbiased estimates of Cox model hazard ratios for these complex mis-measured exposure functions, an extended risk set regression calibration (RRC) method for Cox models is developed and applied to a study of long-term exposure to the fine particulate matter ($PM_{2.5}$) component of air pollution in relation to all-cause mortality in the Nurses\u27 Health Study. Simulation studies under several realistic assumptions about the measurement error model and about the correlation structure of the repeated exposure measurements were conducted to assess the finite sample properties of this new method, and found that the method has good performance in terms of finite sample bias reduction and nominal confidence interval coverage. User-friendly software has been developed and is available to the general public on the senior author\u27s website

Caratterizzazione di antenna a 22 GHz presso il laboratorio microonde dell’ISCTI

Il Laboratorio Microonde dell’Istituto Superiore delle Comunicazioni e delle Tecnologie dell’Informazione esegue misurazioni su apparati e componenti operanti fino alle frequenze delle onde millimetriche. Il campo delle applicazioni comprende anche la caratterizzazione di alcuni parametri delle antenne ed in questo articolo vengono esposti i risultati ottenuti su di un’antenna paraboloidica offset destinata ad uno spettrometro per il monitoraggio del vapor d’acqua nella media atmosfera in sviluppo presso i laboratori dell’Istituto Nazionale di Geofisica e Vulcanologia di Roma