130,566 research outputs found
Atlante degli ordini, delle congregazioni religiose e degli istituti secolari in Puglia. Saggio introduttivo di C. D. Fonseca
No full textProjector Model for Efficient List-Mode Reconstruction in PET Scanners with Parallel Planar Detectors
No full textWe have developed a new projector model specifically tailored for fast list-mode tomographic reconstructions in Positron emission tomography (PET) scanners with parallel planar detectors. The model provides an accurate estimation of the probability distribution of coincidence events defined by pairs of scintillating crystals. This distribution is parameterized with 2D elliptical Gaussian functions defined in planes perpendicular to the main axis of the tube of response (TOR). The parameters of these Gaussian functions have been obtained by fitting Monte Carlo simulations that include positron range, acolinearity of gamma rays, as well as detector attenuation and scatter effects. The proposed model has been applied efficiently to list-mode reconstruction algorithms. Evaluation with Monte Carlo simulations over a rotating high resolution PET scanner indicates that this model allows to obtain better recovery to noise ratio in OSEM (ordered-subsets, expectation-maximization) reconstruction, if compared to list-mode reconstruction with symmetric circular Gaussian TOR model, and histogram-based OSEM with precalculated system matrix using Monte Carlo simulated models and symmetries
Incentivi alla ricerca e sviluppo in Italia: una indagine sugli effetti della Legge 46/82
No full textThe current economic crisis has put government intervention and policy evaluation at the centre of the debate on industrial development policy. Government efforts to stimulate a structural change of Italian industries are needed and in this context it becomes fundamental to engage in evaluation exercises in order to understand what policies are working. The paper offers an evaluation exercise on the major instruments used to promote R&D and innovation activities of Italian firms. We concentrate in particular on Law 46/82 and we look at the effects of the incentives it provides on firms expenditures on R&D and on new employment generation. We also consider the effects of such incentives when other similar laws are at work. Results suggest that a rethinking of the system of incentives might be needed to limit an inefficient overlapping of instruments.Evaluation of industrial policies; R&D and innovation; R&D incentives
La nostra esperienza nel trattamento ortopedico-ortodontico nei pazienti affetti da LPS.
No full textMeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Are they still warriors? Reflections on the use of Maori lexis in New Zealand English
No full textNew Zealand English (NZE) is a language whose vocabulary has been strongly influenced by British, Scottish and Irish but what makes it uniquely different from any other English variety is the presence of words in te reo maori, i.e. the Maori language (Bell & Kuiper, 2000). The first borrowings from Maori came into NZE when the country was colonized (at the end of the 18th century): most of them were words for plants and animals, some were cultural terms. Since then, a rather large number of Maori words have found their way both in spoken and written NZE (Kennedy, 2001). This paper concerns present-day written NZE and is motivated by two general observations: 1) Maori terms can be found in New Zealand books and newspapers without any translation into English, indicating that most New Zealanders know – or allegedly know – what they mean; 2) most of them are used exclusively in connection with Maori culture, which points at their no more than partial integration into NZE (Trudgill & Hannah, 2002). For the present study five Maori words have been selected, namely aroha (‘love’), mana (‘power’), marae (‘meeting ground’), tapu (‘taboo’), and whakapapa (‘genealogy’), on the basis of their frequency of occurrence in NZE and their significance in terms of cultural identity. The analysis (both quantitative and qualitative) will be carried out working on a corpus of on-line NZ newspapers and magazines published in the last three years in order to investigate the five Maori words in their contexts of use. The study aims at pointing out: a)what has been lost of the original meanings, b) which new meanings have been added, c) the extent to which the use of these words contributes to the maintenance and/or creation of cultural stereotypes and d)the extent to which the use of these words can be taken as a reflection of assimilationist policies
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
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