53 research outputs found

    Constructing bibliometric networks: A comparison between full and fractional counting

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    The analysis of bibliometric networks, such as co-authorship, bibliographic coupling, and co-citation networks, has received a considerable amount of attention. Much less attention has been paid to the construction of these networks. We point out that different approaches can be taken to construct a bibliometric network. Normally the full counting approach is used, but we propose an alternative fractional counting approach. The basic idea of the fractional counting approach is that each action, such as co-authoring or citing a publication, should have equal weight, regardless of for instance the number of authors, citations, or references of a publication. We present two empirical analyses in which the full and fractional counting approaches yield very different results. These analyses deal with co-authorship networks of universities and bibliographic coupling networks of journals. Based on theoretical considerations and on the empirical analyses, we conclude that for many purposes the fractional counting approach is preferable over the full counting one

    Differences in scientific collaboration and their effects on research influence: A quantitative analysis of nursing publications in Latin America (Scopus, 2005-2020)

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    This work is mainly aimed at the detection, visualization and description of the scientific collaboration patterns in the Nursing field in Latin America as a response to the lack of evidence on the implications of collaboration and its effects on the scientific influence in the Nursing field. For this purpose, a retrospective quantitative analysis was conducted by including all the publications classified under the code 2900 in All Science Journal Classification Codes of Scopus, corresponding to the field of General Nursing during 2005Âż2020. A total of 40 countries and 362,354 unique publications were analyzed, although the main subset herein consists of 18,371 unique publications authored by Latin-American institutions. World proportion of Latin-American publications in Nursing is higher than all the publications in the region. This increase is especially remarkable in the latest year of the studied period, which may result from the progressive increase in the numbers of nursing schools, the diversity in the graduate and specialization programs, the creation of scientific societies, and the many conferences carried out recently on Nursing.This work was supported by the Madrid Government (Comunidad de Madrid-Spain) under the Multiannual Agreement with UC3M in the line of Excellence of University Professors (EPUC3M02), and in the context of the V PRICIT (Regional Programme of Research and Technological Innovation) to pay off the onerous article processing charges

    On the quest for currencies of science: Field "exchange rates" for citations and Mendeley readership

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    PurposeThe introduction of “altmetrics” as new tools to analyze scientific impact within the reward system of science has challenged the hegemony of citations as the predominant source for measuring scientific impact. Mendeley readership has been identified as one of the most important altmetric sources, with several features that are similar to citations. The purpose of this paper is to perform an in-depth analysis of the differences and similarities between the distributions of Mendeley readership and citations across fields.Design/methodology/approachThe authors analyze two issues by using in each case a common analytical framework for both metrics: the shape of the distributions of readership and citations, and the field normalization problem generated by differences in citation and readership practices across fields. In the first issue the authors use the characteristic scores and scales method, and in the second the measurement framework introduced in Crespo et al. (2013).FindingsThere are three main results. First, the citations and Mendeley readership distributions exhibit a strikingly similar degree of skewness in all fields. Second, the results on “exchange rates (ERs)” for Mendeley readership empirically supports the possibility of comparing readership counts across fields, as well as the field normalization of readership distributions using ERs as normalization factors. Third, field normalization using field mean readerships as normalization factors leads to comparably good results.Originality/valueThese findings open up challenging new questions, particularly regarding the possibility of obtaining conflicting results from field normalized citation and Mendeley readership indicators; this suggests the need for better determining the role of the two metrics in capturing scientific recognition.Merit, Expertise and Measuremen

    Experimental Methods in Chemical Engineering: Temperature Programmed Reduction-TPR

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    Temperature programmed reduction (TPR) characterizes the oxido\u2010reduction properties of bulk and supported catalysts. H2 or CO pass over a pre\u2010conditioned solid sample as a furnace ramps the temperature at a constant rate. A thermal conductivity detector (TCD) or mass spectrometer records the effluent concentration. In the pre\u2010conditioning step, Ar or He flushes residual air and absorbed water from the solids sample to maximize the signal\u2010to\u2010noise ratio of the TCD signal. We calculate the number of active sites based on the detector signal that correlates with how much hydrogen reacts. The temperature at which it begins to react represents the minimum activation temperature. TPR is cheap, fast, easy to run, and the data is straightforward to interpret. The technique is more popular with chemical engineers than with the broader scientific community. Among the 27 articles that Can. J. Chem. Eng. published in 2016 and 2017[1] that apply TPR to analyze catalysts, 22 mention reactors, 20 report XRD spectra, 18 mention gas chromatography, and another 15 quantify surface area by BET. Synergy with other temperature programmed methods is lower, as only 5 mention temperature programmed desorption, 5 thermal gravimetric analysis, and 3 temperature programmed oxidation

    The influence of highly cited papers on field normalised indicators

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    Field normalised average citation indicators are widely used to compare countries, universities and research groups. The most common variant, the Mean Normalised Citation Score (MNCS), is known to be sensitive to individual highly cited articles but the extent to which this is true for a log-based alternative, the Mean Normalised Log Citation Score (MNLCS), is unknown. This article investigates country-level highly cited outliers for MNLCS and MNCS for all Scopus articles from 2013 and 2012. The results show that MNLCS is influenced by outliers, as measured by kurtosis, but at a much lower level than MNCS. The largest outliers were affected by the journal classifications, with the Science-Metrix scheme producing much weaker outliers than the internal Scopus scheme. The high Scopus outliers were mainly due to uncitable articles reducing the average in some humanities categories. Although outliers have a numerically small influence on the outcome for individual countries, changing indicator or classification scheme influences the results enough to affect policy conclusions drawn from them. Future field normalised calculations should therefore explicitly address the influence of outliers in their methods and reporting

    Prognostic Value of Serum Paraprotein Response Kinetics in Patients With Newly Diagnosed Multiple Myeloma

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    Response kinetics is not well-established as a prognostic marker in multiple myeloma (MM). We developed a mathematical model to assess the prognostic value of serum monoclonal component (MC) response kinetics during 6 induction cycles in 373 newly diagnosed MM patients. The model calculated a resistance parameter that reflects the stagnation in the response after an initial descent, dividing the patients into two kinetics categories with significantly different progression-free survival (PFS). Introduction: Response kinetics is a well-established prognostic marker in acute lymphoblastic leukemia. The situation is not clear in multiple myeloma (MM) despite having a biomarker for response monitoring (monoclonal component [MC]). Materials and Methods: We developed a mathematical model to assess the prognostic value of serum MC response kinetics during 6 induction cycles, in 373 NDMM transplanted patients treated in the GEM2012Menos65 clinical trial. The model calculated a resistance parameter that reflects the stagnation in the response after an initial descent. Results: Two patient subgroups were defined based on low and high resistance, that respectively captured sensitive and refractory kinetics, with progression-free survival (PFS) at 5 years of 72% and 59% (HR 0.64, 95% CI 0.44-0.93; P =.02). Resistance significantly correlated with depth of response measured after consolidation (80.9% CR and 68.4% minimal residual disease negativity in patients with sensitive vs. 31% and 20% in those with refractory kinetics). Furthermore, it modulated the impact of reaching CR after consolidation; thus, within CR patients those with refractory kinetics had significantly shorter PFS than those with sensitive kinetics (median 54 months vs. NR; P =.02). Minimal residual disease negativity abrogated this effect. Our study also questions the benefit of rapid responders compared to late responders (5-year PFS 59.7% vs. 76.5%, respectively [P <.002]). Of note, 85% of patients considered as late responders were classified as having sensitive kinetics. Conclusion: This semi-mechanistic modeling of M-component kinetics could be of great value to identify patients at risk of early treatment failure, who may benefit from early rescue intervention strategies. (C) 2022 The Authors. Published by Elsevier Inc

    Identification of research communities in cited and uncited publications using a co-authorship network

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    Patterns of co-authorship provide an effective means of probing the structures of research communities. In this paper, we use the CiteSpace social network tool and co-authorship data from the Web of Science to analyse two such types of community. The first type is based on the cited publications of a group of highly productive authors in a particular discipline, and the second on the uncited publications of those highly productive authors. These pairs of communities were generated for three different countries—the People’s Republic of China (PRC), the United Kingdom (UK) and the United States of America (USA)—and for four different disciplines (as denoted by Web of Science subject categories)—Chemistry Organic, Engineering Environmental, Economics, and Management. In the case of the UK and USA, the structures of the cited and uncited communities in each of the four disciplines were markedly different from each other; in the case of the PRC, conversely, the cited and uncited PRC communities had broadly similar structures that were characterised by large groups of connected authors. We suggest that this may arise from a greater degree of guest or honorary authorship in the PRC than in the UK or the USA
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