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This checklist gives information on a number of species of Cactaceae included in Appendices I and II of CITES regarding their identification, nomenclature and distribution. It is a first step towards a better implementation of CITES for this group of plants.
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How common is self-citation in scholarly publication, and does the practice vary by gender? Using novel methods and a data set of 1.5 million research papers in the scholarly database JSTOR published between 1779 and 2011, the authors find that nearly 10 percent of references are self-citations by a paperâs authors. The findings also show that between 1779 and 2011, men cited their own papers 56 percent more than did women. In the last two decades of data, men self-cited 70 percent more than women. Women are also more than 10 percentage points more likely than men to not cite their own previous work at all. While these patterns could result from differences in the number of papers that men and women authors have published rather than gender-specific patterns of self-citation behavior, this gender gap in self-citation rates has remained stable over the last 50 years, despite increased representation of women in academia. The authors break down self-citation patterns by academic field and number of authors and comment on potential mechanisms behind these observations. These findings have important implications for scholarly visibility and cumulative advantage in academic careers.
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To protect biodiversity, more, improved biological and trade data and analyses are needed.
We report a method for estimating what percentage of people who cited a paper had actually read it. The method is based on a stochastic modeling of the citation process that explains empirical studies of misprint distributions in citations (which we show follows a Zipf law). Our estimate is that only about 20% of citers read the original.
In this study, we extended co-indexing of transcriptomes and epitopes (CITE) to the spatial dimension and demonstrated high-plex protein and whole transcriptome co-mapping. We profiled 189 proteins and whole transcriptome in multiple mouse tissue types with spatial CITE sequencing and then further applied the method to measure 273 proteins and transcriptome in human tissues, revealing spatially distinct germinal center reactions in tonsil and early immune activation in skin at the Coronavirus Disease 2019 mRNA vaccine injection site.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOfficial Methods of Analysis ofCite this: Anal. Chem. 1980, 52, 2, 148APublication Date (Print):February 1, 1980Publication History Published online31 May 2012Published inissue 1 February 1980https://doi.org/10.1021/ac50052a726RIGHTS & PERMISSIONSArticle Views435Altmetric-Citations8LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (758 KB) Get e-Alerts Get e-Alerts
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTColorimetric Method for Determination of Sugars and Related SubstancesMichel. DuBois, K. A. Gilles, J. K. Hamilton, P. A. Rebers, and Fred. SmithCite this: Anal. Chem. 1956, 28, 3, 350–356Publication Date (Print):March 1, 1956Publication History Published online1 May 2002Published inissue 1 March 1956https://pubs.acs.org/doi/10.1021/ac60111a017https://doi.org/10.1021/ac60111a017research-articleACS PublicationsRequest reuse permissionsArticle Views60836Altmetric-Citations37027LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
BCL3 and Sheehy cite Bergey's manual of determinative bacteriology of which systematic bacteriology, first edition, is an expansion. With v.4 the set is complete. The volumes cover, roughly, v.1, the Gram-negatives except those in v.3 ($87.95); v.2, the Gram-positives less actinomycetes ($71.95); v.
Share Icon Share Twitter Facebook Reddit LinkedIn Reprints and Permissions Cite Icon Cite Search Site Citation Robert C. Reid, Thomas K. Sherwood, Robert E. Street; The Properties of Gases and Liquids. Physics Today 1 April 1959; 12 (4): 38–40. https://doi.org/10.1063/1.3060771 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentPhysics Today Search Advanced Search
Arguably the greatest single work in the history of psychology. James's analyses of habit, the nature of emotion, the phenomenology of attention, the stream of thought, the perception of space, and the multiplicity of the consciousness of self are still widely cited and incorporated into contemporary theoretical accounts of these phenomena.
Purpose The purpose of this paper is to present a narrative review of studies on the citing behavior of scientists, covering mainly research published in the last 15 years. Based on the results of these studies, the paper seeks to answer the question of the extent to which scientists are motivated to cite a publication not only to acknowledge intellectual and cognitive influences of scientific peers, but also for other, possibly non‐scientific, reasons. Design/methodology/approach The review covers research published from the early 1960s up to mid‐2005 (approximately 30 studies on citing behavior‐reporting results in about 40 publications). Findings The general tendency of the results of the empirical studies makes it clear that citing behavior is not motivated solely by the wish to acknowledge intellectual and cognitive influences of colleague scientists, since the individual studies reveal also other, in part non‐scientific, factors that play a part in the decision to cite. However, the results of the studies must also be deemed scarcely reliable: the studies vary widely in design, and their results can hardly be replicated. Many of the studies have methodological weaknesses. Furthermore, there is evidence that the different motivations of citers are “not so different or ‘randomly given’ to such an extent that the phenomenon of citation would lose its role as a reliable measure of impact”. Originality/value Given the increasing importance of evaluative bibliometrics in the world of scholarship, the question “What do citation counts measure?” is a particularly relevant and topical issue.
Many studies (in information science) have looked at the growth of science. In this study, we reexamine the question of the growth of science. To do this we (a) use current data up to publication year 2012 and (b) analyze the data across all disciplines and also separately for the natural sciences and for the medical and health sciences. Furthermore, the data were analyzed with an advanced statistical technique—segmented regression analysis—which can identify specific segments with similar growth rates in the history of science. The study is based on two different sets of bibliometric data: (a) the number of publications held as source items in the Web of Science ( WoS , T homson R euters) per publication year and (b) the number of cited references in the publications of the source items per cited reference year. We looked at the rate at which science has grown since the mid‐1600s. In our analysis of cited references we identified three essential growth phases in the development of science, which each led to growth rates tripling in comparison with the previous phase: from less than 1% up to the middle of the 18th century, to 2 to 3% up to the period between the two world wars, and 8 to 9% to 2010.
CONTEXT: Controversy and uncertainty ensue when the results of clinical research on the effectiveness of interventions are subsequently contradicted. Controversies are most prominent when high-impact research is involved. OBJECTIVES: To understand how frequently highly cited studies are contradicted or find effects that are stronger than in other similar studies and to discern whether specific characteristics are associated with such refutation over time. DESIGN: All original clinical research studies published in 3 major general clinical journals or high-impact-factor specialty journals in 1990-2003 and cited more than 1000 times in the literature were examined. MAIN OUTCOME MEASURE: The results of highly cited articles were compared against subsequent studies of comparable or larger sample size and similar or better controlled designs. The same analysis was also performed comparatively for matched studies that were not so highly cited. RESULTS: Of 49 highly cited original clinical research studies, 45 claimed that the intervention was effective. Of these, 7 (16%) were contradicted by subsequent studies, 7 others (16%) had found effects that were stronger than those of subsequent studies, 20 (44%) were replicated, and 11 (24%) remained largely unchallenged. Five of 6 highly-cited nonrandomized studies had been contradicted or had found stronger effects vs 9 of 39 randomized controlled trials (P = .008). Among randomized trials, studies with contradicted or stronger effects were smaller (P = .009) than replicated or unchallenged studies although there was no statistically significant difference in their early or overall citation impact. Matched control studies did not have a significantly different share of refuted results than highly cited studies, but they included more studies with "negative" results. CONCLUSIONS: Contradiction and initially stronger effects are not unusual in highly cited research of clinical interventions and their outcomes. The extent to which high citations may provoke contradictions and vice versa needs more study. Controversies are most common with highly cited nonrandomized studies, but even the most highly cited randomized trials may be challenged and refuted over time, especially small ones.
The goal of this study was to examine the effects of transformational leadership behaviors, within the context of Kerr and Jermier's (1978) substitutes for leadership. Data were collected from 1539 employees across a wide variety of different industries, organizational settings, and job levels. Hierarchical moderated regression analysis procedures generally showed that few of the substitutes variables moderated the effects of the transformational leader behaviors on followers' attitudes, role perceptions, and “in-role” and “citizenship” behaviors in a manner consistent with the predictions of Howell, Dorfman and Kerr (1986). However, the results did show that: (a) the transformational leader behaviors and substitutes for leadership each had unique effects on follower criterion variables; (b) the total amount of variance accounted for by the substitutes for leadership and the transformational leader behaviors was substantially greater than that reported in prior leadership research; and (c) several of the transformational behaviors were significantly related to several of the substitutes for leadership variables. Implications of these findings for our understanding of the effects of transformational leader behaviors and substitutes for leadership are then discussed.
Prior to 1985 the Food and Agriculture Organization (FAO) estimated global food crop contamination with mycotoxins to be 25%. The origin of this statement is largely unknown. To assess the rationale for it, the relevant literature was reviewed and data of around 500,000 analyses from the European Food Safety Authority and large global survey for aflatoxins, fumonisins, deoxynivalenol, T-2 and HT-2 toxins, zearalenone and ochratoxin A in cereals and nuts were examined. Using different thresholds, i.e. limit of detection, the lower and upper regulatory limits of European Union (EU) legislation and Codex Alimentarius standards, the mycotoxin occurrence was estimated. Impact of different aspects on uncertainty of the occurrence estimates presented in literature and related to our results are critically discussed. Current mycotoxin occurrence above the EU and Codex limits appears to confirm the FAO 25% estimate, while this figure greatly underestimates the occurrence above the detectable levels (up to 60-80%). The high occurrence is likely explained by a combination of the improved sensitivity of analytical methods and impact of climate change. It is of immense importance that the detectable levels are not overlooked as through diets, humans are exposed to mycotoxin mixtures which can induce combined adverse health effects.
Abstract This article describes a study to ascertain the reasons why certain old papers are still highly cited many years after their publication. Twenty‐three old papers in the subject fields of physics and physical chemistry which are still highly cited were selected, and 978 of the papers that cited them in the period 1974–1975 were studied. A new typology of reasons for citing the papers was devised, and using this typology, it was found that about 40% of the citations were for historical reasons, but that in the remaining 60% of the cases, the old paper is still begin actively used. We discuss some discrepancies between our citation figures and citation figures quoted by Garfield. We also discuss a number of errors which were found, both in citing articles and in Science Citation Index . Finally, calculations indicate that there is a rule that each cited paper is referred to, on average, 1.05‐1.15 times in every paper that cites it, and that this rule has general validity.
This study explores the tendency of authors to recite themselves and others in multiple works over time, using the insights gained to build citation theory. The set of all authors whom an author cites is defined as that author's citation identity. The study explains how to retrieve citation identities from the Institute for Scientific Information's files on Dialog and how to deal with idiosyncrasies of these files. As the author's oeuvre grows, the identity takes the form of a core-and-scatter distribution that may be divided into authors cited only once (unicitations) and authors cited at least twice (recitations). The latter group, especially those recited most frequently, are interpretable as symbols of a citer's main substantive concerns. As illustrated by the top recitees of eight information scientists, identities are intelligible, individualized, and wide-ranging. They are ego-centered without being egotistical. They are often affected by social ties between citers and citees, but the universal motivator seems to be the perceived relevance of the citees' works. Citing styles in identities differ: “scientific-paper style” authors recite heavily, adding to core; “bibliographic-essay style” authors are heavy on unicitations, adding to scatter; “literature-review style” authors do both at once. Identities distill aspects of citers' intellectual lives, such as orienting figures, interdisciplinary interests, bidisciplinary careers, and conduct in controversies. They can also be related to past schemes for classifying citations in categories such as positive–negative and perfunctory–organic; indeed, one author's frequent recitation of another, whether positive or negative, may be the readiest indicator of an organic relation between them. The shape of the core-and-scatter distribution of names in identities can be explained by the principle of least effort. Citers economize on effort by frequently reciting only a relatively small core of names in their identities. They also economize by frequent use of perfunctory citations, which require relatively little context, and infrequent use of negative citations, which require contexts more laborious to set.
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