954 research outputs found

    The relationship between ILL/document supply and journal subscriptions

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    Purpose: The purpose of this article is to provide insights into the relationship between ILL/ document supply and journal subscriptions and to assess recent trends in the ILL service. Design/methodology/Approach: This survey is based on data from the ILL service conducted over the five year period 2005-2009 through the Italian NILDE (Network for Inter-Library Document Exchange) network. Findings: This article bears out important previous findings that ILL is not used as a surrogate for journal subscriptions. This is supported by the analysis of a broad number of titles and over a wide time-range. On the contrary, analysis of data transactions, particularly of the most requested journals, can bring about positive effects on new title acquisitions and negotiations with publishers. This paper also shows, at least for Italy, an overall growth and vitality of ILL, in spite of the widespread availability of e-journals acquired through consortia purchasing. Originality/Value: An insight into the relationship between ILL and journal subscriptions in Italy, a country where few studies have been carried out, and none at all for such a large number of libraries and transactions

    Update on the GRB universal scaling EX,iso_{\rm{X,iso}}-Eγ,iso_{\rm{\gamma,iso}}-Epk_{\rm{pk}} with ten years of SwiftSwift data

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    From a comprehensive statistical analysis of SwiftSwift X-ray light-curves of gamma-ray bursts (GRBs) collected from December 2004 to the end of 2010, we found a three-parameter correlation between the isotropic energy emitted in the rest frame 1-104^4 keV energy band during the prompt emission (Eγ,iso_{\rm{\gamma,iso}}), the rest frame peak of the prompt emission energy spectrum (Epk_{\rm{pk}}), and the X-ray energy emitted in the rest frame 0.3-30 keV observed energy band (EX,iso_{\rm{X,iso}}), computed excluding the contribution of the flares. In this paper, we update this correlation with the data collected until June 2014, expanding the sample size with \sim35% more objects, where the number of short GRBs doubled. With this larger sample we confirm the existence of a universal correlation that connects the prompt and afterglow properties of long and short GRBs. We show that this correlation does not depend on the X-ray light-curve morphology and that further analysis is necessary to firmly exclude possible biases derived by redshift measurements. In addition we discuss about the behavior of the peculiar objects as ultra-long GRBs and we propose the existence of an intermediate group between long and short GRBs. Interestingly, two GRBs with uncertain classification fall into this category. Finally, we discuss the physics underlying this correlation, in the contest of the efficiency of conversion of the prompt γ\gamma-ray emission energy into the kinetic energy of the afterglow, the photosferic model, and the cannonball model.Comment: 11 pages, 5 figures, accepted for publication in MNRA

    The relationship between ILL/document supply and journal subscriptions

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    Purpose: The purpose of this article is to provide insights into the relationship between ILL/ document supply and journal subscriptions and to assess recent trends in the ILL service. Design/methodology/Approach: This survey is based on data from the ILL service conducted over the five year period 2005-2009 through the Italian NILDE (Network for Inter-Library Document Exchange) network. Findings: This article bears out important previous findings that ILL is not used as a surrogate for journal subscriptions. This is supported by the analysis of a broad number of titles and over a wide time-range. On the contrary, analysis of data transactions, particularly of the most requested journals, can bring about positive effects on new title acquisitions and negotiations with publishers. This paper also shows, at least for Italy, an overall growth and vitality of ILL, in spite of the widespread availability of e-journals acquired through consortia purchasing. Originality/Value: An insight into the relationship between ILL and journal subscriptions in Italy, a country where few studies have been carried out, and none at all for such a large number of libraries and transactions

    The relationship between ILL/document supply and journal subscriptions

    Get PDF
    Purpose: The purpose of this article is to provide insights into the relationship between ILL/ document supply and journal subscriptions and to assess recent trends in the ILL service. Design/methodology/Approach: This survey is based on data from the ILL service conducted over the five year period 2005-2009 through the Italian NILDE (Network for Inter-Library Document Exchange) network. Findings: This article bears out important previous findings that ILL is not used as a surrogate for journal subscriptions. This is supported by the analysis of a broad number of titles and over a wide time-range. On the contrary, analysis of data transactions, particularly of the most requested journals, can bring about positive effects on new title acquisitions and negotiations with publishers. This paper also shows, at least for Italy, an overall growth and vitality of ILL, in spite of the widespread availability of e-journals acquired through consortia purchasing. Originality/Value: An insight into the relationship between ILL and journal subscriptions in Italy, a country where few studies have been carried out, and none at all for such a large number of libraries and transactions

    Citation indexes and users’ (in)formation needs. The University of Milan biomedical librarians experience

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    The University of Milan has a 40 years long citation experience. The library of Pharmacy (then library of the Institute of Pharmacological Sciences, director: Prof. Rodolfo Paoletti) purchased the Science Citation Index (SCI) in 1979 (Printed Science Citation Index since 1979-93, CD-Rom in 1994-2000; Journal Citation Reports (JCR) 1981-2000). The online version has been available since 2000 for Web of Science (WOS) and JCR, following the University of Milan subscription. Scopus has been available since 2009, after an agreement between Elsevier and the CRUI (The Conference of Italian University Rectors). Since its inception, SCI and JCR (which were quite expensive) attracted external users interested in assessing citations and in the Impact Factor (IF). Conversely, the use of such indexes for research evaluation had been minimal among professors or reseachers, until the debut – in 2012 – of the Abilitazione Scientifica Nazionale (ASN; National Scientific Qualification). At the end of 2001, the Sistema Bibliotecario di Ateneo (SBA; University Library System) activated courses on the use of WOS and JCR. Scopus was introduced in 2010, under the supervision of biomedical librarians. At the beginning, the majority of participants were only interested in traditional bibliographic searches, with the exception of some researchers who spent some time abroad and some questions on the IF. With the activation of the ASN, the attendees’ profile has radically changed. In addition to the increasing number of participants to the courses on WOS, JCR, and Scopus, their (in)formation needs also greatly changed. Specifically, instead of a mere bibliographic search most users are now interested in bibliometrics, i.e. calculate the H-Index and contemporary H-index, or in solving ambiguities with authors’ names, cleaning up erroneous data, adding missing data, and learning how to use Google Scholar. The average users’ age is decreasing; there are more graduate students and researchers than professors, and participants take more active part to the lessons than before, asking questions about citation analysis and their CV. Following an analysis of participant satisfaction surveys and according to the most common questions asked by attendees, librarians fine-tuned their programs to greatly increase the proportion of citation database use vs. a traditional bibliographic search

    Risultati del questionario esplorativo sulla catalogazione dei periodici elettronici

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    Gamma-ray burst optical light-curve zoo: comparison with X-ray observations

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    We present a comprehensive analysis of the optical and X-ray light curves (LCs) and spectral energy distributions (SEDs) of a large sample of gamma-ray burst (GRB) afterglows to investigate the relationship between the optical and X-ray emission after the prompt phase. We collected the optical data from the literature and determined the shapes of the optical LCs. Then, using previously presented X-ray data we modeled the optical/X-ray SEDs. We studied the SED parameter distributions and compared the optical and X-ray LC slopes and shapes. The optical and X-ray spectra become softer as a function of time while the gas-to-dust ratios of GRBs are higher than the values calculated for the Milky Way and the Large and Magellanic Clouds. For 20% of the GRBs the difference between the optical and X-ray slopes is consistent with 0 or 1=4 within the uncertainties (we did it not consider the steep decay phase), while in the remaining 80% the optical and X-ray afterglows show significantly different temporal behaviors. Interestingly, we find an indication that the onset of the forward shock in the optical LCs (initial peaks or shallow phases) could be linked to the presence of the X-ray flares. Indeed, when X-ray flares are present during the steep decay, the optical LC initial peak or end plateau occurs during the steep decay; if instead the X-ray flares are absent or occur during the plateau, the optical initial peak or end plateau takes place during the X-ray plateau. The forward-shock model cannot explain all features of the optical (e.g. bumps, late re-brightenings) and X-ray (e.g. flares, plateaus) LCs. However, the synchrotron model is a viable mechanism for GRBs at late times. In particular, we found a relationship between the presence of the X-ray flares and the shape of the optical LC that indicates a link between the prompt emission and the optical afterglow.Comment: 55 pages, 37 figures, accepted for publication in A&A (this version includes changes made at Proofs stage

    Are postnatal traumatic events an underestimated cause of porencephalic lesions in dogs and cats?

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    IntroductionPorencephaly is defined as a fluid-filled cavity of variable size in the brain cortex. It is regarded as a congenital condition and is typically considered a developmental or an encephaloclastic defect. Our hypothesis is that postnatal traumatic events in the first few months of life may represent a cause of canine and feline porencephaly that is more common than generally suspected. The aims of this study were to retrospectively investigate porencephaly in a large population of dogs and cats, detect MRI features that might be useful to differentiate postnatal acquired traumatic forms from congenital/perinatal porencephaly, and define the prevalence of seizure activity in porencephalic patients.Materials and methodsThis is a double-center, descriptive, retrospective case series. Databases were searched for cases within a 17-year time span that involve dogs and cats with an MRI-based diagnosis of cerebral cavitary lesions. Animals were included if a complete signalment and an exhaustive MRI of the brain were available. Besides the porencephalic lesions, MRIs of the head were reviewed to detect concomitant musculoskeletal abnormalities.ResultsThirty-two cases involving nine cats and twenty-three dogs were selected. Of all the cases, 21.9% were aged six years or older at the time of diagnosis. All patients in which the neuroanatomical localization was available showed clinical signs of a prosencephalic disorder. Epileptic seizures were observed in 71.8% of cases. A single porencephalic cavity was found in 78.1% of cases. The most affected cerebral lobe was the parietal lobe (n = 20). The defects involved both the grey and white matter in 78.1% of cases. Twenty cases showed concomitant musculoskeletal abnormalities overlying the porencephalic cavities. Fourteen of twenty cases showed evidence of fractures, of which thirteen showed depression of the calvarium and twelve masticatory muscle abnormalities. Of these, seven of fourteen had a history consistent with a head trauma in the first period of life.ConclusionThe recognition of skull fractures and muscular abnormalities closely associated with the porencephalic cavity may support a diagnosis of a postnatal traumatic origin of porencephaly. Therefore, this study highlights the importance of evaluating musculoskeletal structures in the MRIs of the heads of porencephalic cases
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