74 resultados para Library statistics.
Resumo:
We present a case study of the redesign of the organizational presentation and content of the Virtual Library website at the Universitat Oberta de Catalunya (Open University of Catalonia, UOC), based on a user-centered design strategy. The aim of the redesign was to provide users with more intuitive, usable and understandable content (textual content, resources and services) by implementing criteria of customization, transparency and proximity. The study also presents a selection of best practices for applying these criteria to the design of other library websites.
Resumo:
This abstract presents how we redesigned, with user-centred design methods, the way we organize and present the content on the UOC Virtual Library website. The content is now offered in a way that is more intuitive, usable and easy to understand, based on criteria of customization, transparency and proximity.The techniques used to achieve these objectives included benchmarking, interviews and focus groups during the user requirement capture phase and user tests to assess the process and results.
Resumo:
Objectives: Publication bias may affect the validity of evidence based medical decisions. The aim of this study is to assess whether research outcomes affect the dissemination of clinical trial findings, in terms of rate, time to publication, and impact factor of journal publications. Methods and Findings: All drug-evaluating clinical trials submitted to and approved by a general hospital ethics committee between 1997 and 2004 were prospectively followed to analyze their fate and publication. Published articles were identified by searching Pubmed and other electronic databases. Clinical study final reports submitted to the ethics committee, final reports synopses available online and meeting abstracts were also considered as sources of study results. Study outcomes were classified as positive (when statistical significance favoring experimental drug was achieved), negative (when no statistical significance was achieved or it favored control drug) and descriptive (for non-controlled studies). Time to publication was defined as time from study closure to publication. A survival analysis was performed using a Cox regression model to analyze time to publication. Journal impact factors of identified publications were recorded. Publication rate was 48·4% (380/785). Study results were identified for 68·9% of all completed clinical trials (541/785). Publication rate was 84·9% (180/212) for studies with results classified as positive and 68·9% (128/186) for studies with results classified as negative (p<0·001). Median time to publication was 2·09 years (IC95 1·61-2·56) for studies with results classified as positive and 3·21 years (IC95 2·69-3·70) for studies with results classified as negative (hazard ratio 1·99 (IC95 1·55-2·55). No differences were found in publication impact factor between positive (median 6·308, interquartile range: 3·141-28·409) and negative result studies (median 8·266, interquartile range: 4·135-17·157). Conclusions: Clinical trials with positive outcomes have significantly higher rates and shorter times to publication than those with negative results. However, no differences have been found in terms of impact factor.
Resumo:
Purpose- This study seeks to analyse the policies of library and information science (LIS) journals regarding the publication of supplementary materials, the number of journals and articles that include this feature, the kind of supplementary materials published with regard to their function in the article, the formats employed and the access provided to readers. Design/methodology/approach- The study analysed the instructions for authors of LIS journals indexed in the ISI Journal Citation Reports, as well as the supplementary materials attached to the articles published in their 2011 online volumes. Findings- Large publishers are more likely to have a policy regarding the publication of supplementary materials, and policies are usually homogeneous across all the journals of a given publisher. Most policies state the acceptance of supplementary materials, and even journals without a policy also publish supplementary materials. The majority of supplementary materials provided in LIS articles are extended methodological explanations and additional results in the form of textual information in PDF or Word files. Some toll-access journals provide open access to any reader to these files. Originality/value- This study provides new insights into the characteristics of supplementary materials in LIS journals. The results may be used by journal publishers to establish a policy on the publication of supplementary materials and, more broadly, to develop data sharing initiatives in academic settings.
Resumo:
In this article, the fusion of a stochastic metaheuristic as Simulated Annealing (SA) with classical criteria for convergence of Blind Separation of Sources (BSS), is shown. Although the topic of BSS, by means of various techniques, including ICA, PCA, and neural networks, has been amply discussed in the literature, to date the possibility of using simulated annealing algorithms has not been seriously explored. From experimental results, this paper demonstrates the possible benefits offered by SA in combination with high order statistical and mutual information criteria for BSS, such as robustness against local minima and a high degree of flexibility in the energy function.
Resumo:
Conferència Organitzada per l'Escola Politècnica Superior, Universitat de Vic en col·laboració amb Servei d'Estadística de la Universitat Autònoma de Barcelona i CosmoCaixa Barcelona. Celebrada del 18 al 22 de juny de 2012 a Barcelona
Resumo:
In the present work we focus on two indices that quantify directionality and skew-symmetrical patterns in social interactions as measures of social reciprocity: the Directional consistency (DC) and Skew symmetry indices. Although both indices enable researchers to describe social groups, most studies require statistical inferential tests. The main aims of the present study are: firstly, to propose an overall statistical technique for testing null hypotheses regarding social reciprocity in behavioral studies, using the DC and Skew symmetry statistics (Φ) at group level; and secondly, to compare both statistics in order to allow researchers to choose the optimal measure depending on the conditions. In order to allow researchers to make statistical decisions, statistical significance for both statistics has been estimated by means of a Monte Carlo simulation. Furthermore, this study will enable researchers to choose the optimal observational conditions for carrying out their research, as the power of the statistical tests has been estimated.
Resumo:
LORs, addressing content management and preservation, have the positive collaterals of institutional positioning and dissemination, but their main benefit is the empowerment of interest-centred learning communities, as we recognise that learning is much more than content, which becomes infrastructure: the LOR provides the learner interaction with the LOs, but also with other learners and teachers.
Resumo:
This report was requested by the Innovation and Marketing department of the ETHBibliotek, for the purpose of assessing the social cataloguing tool LibraryThing and its potential uses in an academic library.
Resumo:
Larnellarins are a group of marine natural products isolated from the prosobranch mollusc Lamellaria sp., the ascidian Didemnum sp., and the sponge Dendrilla Cactos. Several of them exhibit interesting biological activities. Natural as well as synthetic lamellarins should be excellent candidates for the development of new drugs due to their unique skeletal structure and their important biological activities especially as antitumor agents. Lamelarin O has been recently characterized as a topoisomerase 1-targeted anti tumor agent. A variety of synthetic approaches have been developed for this family of alkaloids. Herein we describe a new route to the synthesis of Lamellarin D, from a methyl 2-pyrrolecarboxylate. Transformation of the starting material into the scaffold, a substituted 5,6-dihydropyrrolo (2,l a)isoquinoline (5,6-DHPl), was afforded by N-alkylation followed by intramolecular Heck cyclization. From this scaffold the synthetic strategy is based on two sequential regioselective bromination!Suzuki cross-coupling reactions which permitted the introduction of differently substituted aryl groups on positions 1 and 2 followed by oxidation, deprotection, and lactonization.
Resumo:
The reduction of quantum scattering leads to the suppression of shot noise. In this Letter, we analyze the crossover from the quantum transport regime with universal shot noise to the classical regime where noise vanishes. By making use of the stochastic path integral approach, we find the statistics of transport and the transmission properties of a chaotic cavity as a function of a system parameter controlling the crossover. We identify three different scenarios of the crossover.
Resumo:
El pasado 23 de junio se celebró en Londres una jornada dedicada a los resultados del proyecto LIFE (Life Cycle Information for E-Literature)
Resumo:
The origins of early farming and its spread to Europe have been the subject of major interest for some time. The main controversy today is over the nature of the Neolithic transition in Europe: the extent to which the spread was, for the most part, indigenous and animated by imitatio (cultural diffusion) or else was driven by an influx of dispersing populations (demic diffusion). We analyze the spatiotemporal dynamics of the transition using radiocarbon dates from 735 early Neolithic sites in Europe, the Near East, and Anatolia. We compute great-circle and shortest-path distances from each site to 35 possible agricultural centers of origin—ten are based on early sites in the Middle East and 25 arehypothetical locations set at 58 latitude/longitude intervals. We perform a linear fit of distance versus age (and viceversa) for each center. For certain centers, high correlation coefficients (R . 0.8) are obtained. This implies that a steady rate or speed is a good overall approximation for this historical development. The average rate of the Neolithic spread over Europe is 0.6–1.3 km/y (95% confidence interval). This is consistent with the prediction of demic diffusion(0.6–1.1 km/y). An interpolative map of correlation coefficients, obtained by using shortest-path distances, shows thatthe origins of agriculture were most likely to have occurred in the northern Levantine/Mesopotamian area