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China has made great progress in economy and science in the last two decades. Its scientific development in gastroenterology has been seldom reported. Using two authoritative bibliographic databases, Science Citation Index Expanded (SCI-E) and Medline, we analyze China's research output in gastroenterology journals from 1990 to 2004. After detailed analysis, we found that China have greatly advanced in gastroenterology research, but the growth of Chinese articles in gastroenterology journals can largely be attributed to the selection of China-based journals into international bibliographic databases.

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This research uses descriptive multivariate data-analytic techniques—in particular, multidimensional scaling and hierarchical cluster analysis—to explore and visualize the structure of the pharmacy literature as refracted through the editorial policies of theInternational Pharmaceutical Abstracts (IPA) database. Specifically, the co-occurrence of the section headings/codes, used to exhaustively categorize publications in the IPA database, are clustered and mapped to evaluate the usefulness of two methods of section heading assignment. A secondary purpose of this research is to evaluate the use of descriptive multivariate data-analytic techniques and co-classification analysis to explore and depict the structure of an inherently heterogeneous and multidisciplinary professional literature, such as pharmacy.

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Values of 2200 m.s-1 cross sections, together with the associated nuclear data, are tabulated for 128 (n,g) reactions of interest in NAA. The values are derived from the Y2K database of experimentally measured k 0-factors.

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For the past eight years, the author has been examining trends in access to international scientific literature in major international bibliographic databases available on various information systems. A major portion of the research program examined and compared the languages of documents and countries of publication for items published between 1970–1990 and recorded on MEDLINE, PsycInfo, BIOSIS, Chemical Abstracts, and other databases on the DIALOG system. The second phase of this study examines the remaining scientific databases on DIALOG, including MATHFILE and AGRICOLA. A comparison of the international range of MEDLINE and EMBASE has also recently been completed. In order to attempt to assess actual amounts of literature produced, the Unesco statistics for literature production have been studied. In the course of this research, the author encountered a variety of system attributes that affect the ways in which Third World science can be identified. Some of the policies and procedures of database development that affect the inclusion of Third World science have been identified.

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The aim of this study was to draw attention to the possible existence of "quirk", inbibliographic databases and to discuss their implications. We analysed the time-trends of"publication types" (PTs) relating to clinical medicine in the most frequently searched medicaldatabase, MEDLINE. We counted the number of entries corresponding to 10 PTs indexed inMEDLINE (1963-1998) and drew up a matrix of [10 PTs × 36 years] which we analysed bycorrespondence factor analysis (CFA). The analysis showed that, although the "internal clock" ofthe database was broadly consistent, there were periods of erratic activity. Thus, observed trendsmight not always reflect true publication trends in clinical medicine but quirks in MEDLINEindexing of PTs. There may be, for instance, different limits for retrospective tagging of entriesrelating to different PTs. The time-trend for Reviews of Reported Cases differed substantiallyfrom that of other publication types.Despite the quirks, quite rational explanations could be provided for the strongest correlationsamong PTs. The main factorial map revealed how the advent of the Randomised Controlled Trial(RCT) and the accumulation of a critical mass of literature may have increased the rate ofpublication of research syntheses (meta-analyses, practice guidelines...). The RCT is now theiogold standardls in clinical investigation and is often a key component of formal "systematicreviews" of the literature. Medical journal editors have largely contributed to this situation andthus helped to foster the birth and development of a new paradigm, "evidence based medicine"which assumes that expert opinion is biased and therefore relies heavily — virtually exclusively —on critical analysis of the peer-reviewed literature. Our exploratory factor analysis, however, leadsus to question the consistency of MEDLINEs indexing procedures and also the rationale forMEDLINE's choice of descriptors. Databases have biases of their own, some of which are notindependent of expert opinion. User-friendliness should not make us forget that outputs depend onhow the databases are constructed and structured.

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The elemental composition of human hair obtained from different studies at Surrey University over a period of 25 years has been recorded and forms part of a database, for biological and environmental samples, which is being developed. Instrumental neutron activation analysis (INAA), using reactor neutrons, was the principal method employed and from which reported data are presented.Elemental concentrations of Br, Ca, Ce, Cl, Co, Cr, Cs, F, Fe, Hf, K, Mg, Mn, Na, Rb, Sb, Sc, Se, V and Zn were obtained and recorded in the database. Chronological variations in two sets of subjects separated by a period of time of 16 years are also given. Variations in the concentration values of some elements related to the state of health and disease were reported for hair samples collected from subjects suffering from manic depression, senile dementia and breast cancer. Concentration values of some elements with relation to the nationality of subjects from Bulgaria, England, Kenya, Nigeria and Wales are presented and compared. This study is part of on-going research in the analysis of biomedical and bioenvironmental materials. The database is still in its infancy.

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The National Citation Report (NCR) is an integrated citation file supplied by the Institute for Scientific Information (ISI), of an individual country's articles in science and social sciences. Our experience with the NCR database for Mexico suggests that this is an important addition to the tools available for carrying out bibliometric analysis of research performance. However, in order to generate reliable and accurate indicators using these datafiles we recommend that these be handled by specialists well acquainted with the ISI information products and with the scientific setup of the country concerned.

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This article introduced two sampling methods, including Directly Random Sampling (DRS) and Redistributed Random Sampling (RRS) methods for categorization of a large number of research articles retrieved from metallurgy and polymer subfields from the Science Citation Index (SCI) database. The accuracy of the proposed sampling methods was considered in association by comparing with reference results previously obtained by Fully Retrieving Sampling (FRS) method, which involved analyzing the contents and categories of all articles from the database. The results suggested that RRS and DRS methods were appropriate, efficient and reasonably accurate for categorization of relatively large volume of research articles. RRS method was highly recommended, especially when the contents of sample articles was unevenly distributed. By DRS and RRS methods, only about 6.3% of total articles were required for obtaining similar results as those given by FRS method. The percentage Expected Worst Errors (EWE) from DRS and RRS methods were observed to range from 1.0 to 5.5%. The EWE value could be reduced by increasing the sample size.

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This article presents results of a study on the applicability of journal mapping of knowledge domains beyond the databases produced by the Institute for Scientific Information (ISI). The utility and validity of this generalisation is discussed with an emphasis on its added value in comparison to traditional ISI-based journal maps, i.e. those restricted to (predominantly English-language) ISI-covered journals, and journal-to-journal citation data retrieved from ISI'sJournal Citation Reports. The mapping methodology was applied to Manufacturing technology and management — a multidisciplinary domain situated on the interface of science and technology. TheInternational Journal of Production Economics was singled out as a special case for the validation study of the maps. Results of this study, involving several subject experts, indicate that a journal content-based map was not only far superior to the journal citation map, but also outperformed the map derived from the combination of both types of data. The selection of periodicals from other databases such as COMPENDEX produced a substantial number of additional titles of which only half were also covered by ISI.

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This paper argues the convenience of considering multiple databases in order to obtain a reliable set of scientific indicators in case of fields that includes a variety of disciplines. With this aim we analyse the Spanish scientific output in Plant Sciences regarding mainstream literature covered by SCI database and that published in domestic journals covered by ICYT database. This method allows us to obtain two different profiles of research. These results clearly underly the need to consider these databases jointly, thus avoiding potential inaccuracies induced by the use of the SCI as the only information source to be considered for the assessment of research.

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