Highly Visible Science: A Look at Three Decades of Research from Four Iberamerican Countries

The present research-in-progress illustrates how a simple analysis of high-ranking journals can give valuable information on the scientific visibility of countries, especially those from developing regions. Latin American research in the multidisciplinary journals Nature and Science was determined by analysing the papers published from 1973 to November 2004, by the region's three most productive countries, Argentina, Brazil and Mexico, and comparing these with Spain. A bibliometric and data mining software was developed to analyse corresponding records from the Web of Science with respect to the following parameters: total number of papers, publications by year and by author, collaborations by country and by institution, times cited, cited journals, and significant words in the abstracts of the papers. Preliminary results with respect to some of these parameters show the usefulness of the method developed. Introduction A special concern for developing countries is the extent to which their science is visible to the international scientific community and, especially, how much of their contribution to global science can be considered at the cutting edge of international research. Of all mainstream journals, the two multidisciplinary, weekly journals, Nature and Science are the best-known and most widely read. The specific criteria for publication of scientific papers in Nature are two-fold, that they be of outstanding scientific performance and reach a conclusion of interest to an interdisciplinary readership. Only about 10% of papers received are published hence selection criteria are rigorous (Getting published in Nature, 2004). In the case of Science, the guidelines for authors state that priority is given to papers that reveal novel concepts of broad interest and that competition for space in Science is keen (Information and help for Science authors, 2004). We can therefore consider that papers published in these two journals reach a far broader audience, both within and outside the international scientific community, than those published in specialist journals. Thus publication in these two widely-read journals can be taken as a measure of the international visibility of the research performed by countries such as those from Latin America, as well as identifying research work that is at the forefront of its field. In the present paper we develop a straightforward method for rating the scientific visibility of countries, using publication in Science and Nature as indicators. Method Taking three Spanish and one Portuguese-speaking countries, Spain, Argentina, Brazil and Mexico, we analysed all publications in the multidisciplinary journals, Nature and Science from 1973 to November 2004. Full records including abstracts, references and citation data, were downloaded individually for each country from the Science Citation Index Expanded using the Web of Science, adopting the following strategy: source (Nature AND Science) AND address, either Spain, Argentina, Brazil or Mexico NOT New. Data were worked using software developed for bibliometric and data mining analysis at the UNAM's Centre for Energy Research (CIE). Groups of records for each country 1 The work presented in this paper was supported by project FOMIX CONACyT-Morelos 9250. 2 Only papers in the parent journal, Nature, were included in the analysis. Highly Visible Science: A Look at Three Decades of Research from Four Iberamerican Countries 257 can be analysed with respect to the following variables: Total production and its distribution over time, patterns of international collaboration, most productive authors and institutions, citation frequencies, and cited journals. A text mining technique can be used (Ortuno et al., 2002) to find the most relevant words occurring in the abstracts of papers of all four countries. A normalised standard deviation higher than 1 indicates that the distribution of the word within a particular abstract is not random allowing us to determine which words or string of words can be considered relevant for that particular text. The advantage of this technique is that it does not require a labour-intensive revision of individual words to extract the keywords from a text but rather provides a ready-made list of the most frequently occurring words and strings of words whose distribution within a text is not random and, therefore, likely to be significant. Preliminary Results The total numbers of papers in both journals were as follows: Spain, 625, Brazil, 322, Mexico, 202 and Argentina, 116. Both Spain and Brazil published over 70% of their total papers in Nature, while the production of Mexico and Argentina were more evenly distributed between the two titles. All four countries showed an increasing aggregate presence in the two journals over the 30 years analysed, as can be seen in Figure 1. Argentina, Brazil and Mexico first got into double figures after 1995. Spain showed a notable rise in publications from 1993 onwards even though a steady rise was apparent from the middle of the 80s coinciding with her entry into the European Union. Figure 1: Publications by country per year An analysis of the number of times the publications from each country were cited in subsequent years is given in Figure 2. Almost 28% of Mexican papers remained uncited, the corresponding figure for Argentina was 20%, for Brazil, 16% and for Spain, 15%. Fewer than 28% of publications from Argentina, 28% from Brazil, 25% from Mexico and 20% from Spain received between 1 and 9 citations. The most frequent citations levels greater than 9 were between 10 and 19 for Mexico, from 30-49 for Argentina, and from 50-99 for both Brazil and Spain. The highest level of citation, between 200 and 3000, was achieved by almost 9% of papers from Spain, around 5% from both Brazil and from Mexico and only 3% of Argentine publications. The two most highly cited articles receiving more than 2000 citations, are on the subject of the genome, one of E. coli and the other the human genome, with Mexican and Spanish coauthors, Jane M. Russell, J. Antonio Del Río and Héctor D. Cortés 258 respectively. The most highly cited publications in the group of Argentine and Brazilian publications received less than 1000 citations. Two Spanish articles also in the field of genetics obtained more than 1000 citations. An analysis of the journal titles most frequently cited in the reference lists of a group of papers gives us an indication of the main subject areas of these publications. In the present study, both Nature and Science are, perhaps not surprisingly, the most frequently cited journals, Nature more so than Science (Figure 3). Results show general agreement with the distribution patterns of the publications of the four countries between these two journals with the exception of Mexico which published more papers in Science than in Nature but showed a slightly greater inclination to cite papers from Nature than from Science. Physical Review Letters was the next most frequently referenced journal in the publications of Argentina, Brazil and Spain but not of Mexico. Other frequently cited titles were principally in the areas of astronomy and astrophysics (with the exception of Argentina), geophysics (predominantly Mexico but also Brazil) and, in the case of Spain only, in molecular biology. Papers from all four countries cited the multidisciplinary proceedings of the US National Academy of Sciences. Figure 2: Citation distribution by country The most significant single words found in the abstracts from Argentina were: quantum, proteins, biodiversity, ice, jurassic, and larsen, indicating the presence of papers in physics, biology, and in the geosciences. Analysis of strings of three words revealed important occurrences of the following phrases; the larsen ice shelf, the southern hemisphere, and the australian continent, revealing a concentration of papers published in geosciences of the southern hemisphere. The most relevant words in the Brazilian papers were fire, leprosy, stars, galaxies, and clusters. Gene expression, the amazon, forest fires, tree mortality were common relevant occurrences. However, significant phrases were few and revealed no specific research topics. Our findings suggest that leprosy is a big concern for the Brazilians, as well could be the subject of forest fires. A general interest in astronomy is also apparent. Highly Visible Science: A Look at Three Decades of Research from Four Iberamerican Countries 259 Figure 3: Most highly cited journals. In the case of Mexico, galaxies, nanotubes, chicxulub, genomic, and planetary showed standard deviations greater than 1 indicating three main research thrusts: astronomy, molecular biology, and geosciences. When looking at the phrases, the following themes became apparent: cretaceous tertiary k t boundary, biological nitrogen fixation, and the chicxulub structure. Ozone, insulin, quantum, artic, and mammals were relevant words in the Spanish abstracts. Ozone loss, stem cells, planetary nebulae, black hole, x ray emission conformed relevant phrases corresponding to the general areas of environmental sciences, biological sciences, and astronomy. However, no particular research theme emerged from the present analysis suggesting that Spanish research in many branches of science is present in these mainstream journals. Discussion The present study has demonstrated the usefulness of analysing publications in the two influential, multidisciplinary journals, Nature and Science, to determine a country’s high international scientific profile. Using this method we are able to identify trends in publications, collaborations and citations, as well as prominent institutions and actors, and main research thrusts. The validity of our analysis rests on the assumption that the scientific work published in Nature and Science effectively represents the advancement of scientific knowledge in the global scenario.