46,096 research outputs found

    Celmisia brevifolia Cheeseman 1925

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    <p> <b>11.</b> <i>Celmisia brevifolia</i> Cockayne ex Cheeseman (1925: 938).</p> <p> Type:—NEW ZEALAND. South Island, Plateau of the Old Man Range in herb-moor, 1500 m. alt., 27 March 1919, <i>L. Cockayne 1970</i> (lectotype K 77065 [image!] designated here; isolectotype WELT SP45774!).</p> <p> <b>Notes:—</b> Cheeseman (1925) described <i>C. brevifolia</i> and cited several syntypes that include plants with quite different leaf appearances regarding shape and indumentum. Plants from the Old Man Range (<i>L. Cockayne 1970</i>, see typification) and some from Mt Pisa (<i>L. Cockayne 1978</i>, K 77064 [image!], WELT SP45775!, SP45776!), both in Central Otago, have leaves obovate and pseudopetiolate, upon which Allan (1961: 618) wrote: “Neither type locality nor type is indicated, but Central Otago plants included by Cheeseman are fairly uniform […]”. Another syntype from Mt. Pisa (SP46497!) and one collected at Mt Ernest in northwest Otago (AK 34925!) have leaves that vary from obovate, obovate-oblong, oblanceolate-oblong, to almost linear-oblong, approaching <i>C. angustifolia</i>. Additional syntypes (AK 9707!, 9708!, AK 9709!, 9710!, AK 9706!, WELT SP46498!) coming from the Two Thumb Range in South Canterbury, have a conspicuous white arachnoid indumentum covering most of the adaxial surface (note that the syntypes mentioned above and the typical <i>C. angustifolia</i> are glabrous on the adaxial surface) and leaves oblanceolate-oblong to linearoblong, almost identical to <i>C. angustifolia</i> from its typical area (Torlesse Range, see typification of <i>C. angustifolia</i>).</p> <p> Plants from the Old Man Range are quite uniform in leaf shape and are representative of the taxon commonly recognized as <i>Celmisia brevifolia</i> that occurs mainly in Central Otago (Allan 1961, Mark & Adams 1973) as indicated above.Therefore, I have chosen the material from this locality (<i>L. Cockayne 1970</i>) as a lectotype. Besides, this specimen corresponds to a branch with leaves and one scape with a complete involucre, morphological features that allow its appropriate identification.</p> <p> Cheeseman ascribed the name <i>C. brevifolia</i> to Cockayne, however, according to the ICN Art. 46.5 and 46.6 (Turland <i>et al</i>. 2018), the author can be cited either as <i>C. brevifolia</i> Cheeseman or as <i>C. brevifolia</i> Cockayne ex Cheeseman.</p>Published as part of <i>Saldivia, Patricio, 2023, Nomenclature and typifications in Celmisia (Asteraceae: Astereae): The New Zealand endemic subgenera Caespitosae, Glandulosae, and Lignosae, pp. 31-45 in Phytotaxa 591 (1)</i> on pages 35-36, DOI: 10.11646/phytotaxa.591.1.3, <a href="http://zenodo.org/record/7784168">http://zenodo.org/record/7784168</a&gt

    Magnesium-based glasses prepared by sol-gel processing for use as supplementary cementitious materials

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    Abstract For decades, supplementary cementitious materials (SCMs) have been utilized as clinker substitutes as one of the strategies to mitigate the CO2 emissions associated with Portland cement production. However, traditional SCMs (e.g., coal fly ash, silica fume, and blast furnace slag) are being phased out, as they are insufficient to enable high volume clinker substitution. Therefore, alternative SCMs are actively being sought to meet market demand. Synthetic glasses may be a potential source of SCMs due to their pozzolanic activity and tunable properties. The chemical composition of glasses determines their pozzolanic activity, with Ca-based glasses being predominantly studied owing to their high reactivity. However, this leads to the same inherent CO2 emissions as for cement, originating from the production of CaO from CaCO3. This thesis investigates Mg-based silicate glasses synthesized via the sol-gel method, tuning their composition for higher pozzolanic activity. The feasibility of using Mg-based silicate glasses as SCMs was studied through three main pathways: (1) Development of a binary Mg-Si sol-gel glass system: The impact of varying Mg concentrations on the glass reactivity was assessed (Publication Ⅰ). (2) Introduction of Fe into the Mg-Si system: Varying concentrations of Fe3+/ Fe2+ were incorporated into Mg-Si glasses, investigating changes in reactivity (Publications Ⅱ, Ⅲ). (3) Assessment of cementitious performance: The pozzolanic activity of Mg-based glasses was evaluated, and their impact on the properties and performance of cementitious systems was studied (Publication Ⅳ). The research revealed the high elemental solubility of the synthetic glasses, indicating their high reactivity, and demonstrated pozzolanic activity exceeding that of conventional SCMs such as fly ash slag. These findings provide a preliminary assessment of the potential for using Mg silicate glasses as novel SCMs with the aim of reducing CO2 emissions. Original papers Jiang, C., Ramteke, D. D., Li, J., Sliz, R., Sreenivasan, H., Cheeseman, C., & Kinnunen, P. (2023). Preparation and characterization of binary Mg-silicate glasses via Sol-Gel route. Journal of Non-Crystalline Solids, 606, 122204. https://doi.org/10.1016/j.jnoncrysol.2023.122204 https://doi.org/10.1016/j.jnoncrysol.2023.122204 Self-archived version Jiang, C., Santos, H. S., Yliniemi, J., Lindén, J., Ramteke, D. D., Illikainen, M., Cheeseman, C., & Kinnunen, P. (2024). Fe-bearing magnesium silicate glasses for potential supplementary cementitious applications. Frontiers in Materials, 11, 1509403. https://doi.org/10.3389/fmats.2024.1509403 https://doi.org/10.3389/fmats.2024.1509403 Self-archived version Jiang, C., Yliniemi, J., Santos, H. S., Lindén, J., Ramteke, D.D., Cheeseman, C., & Kinnunen, P. (2024). Optimizing Fe(II)/Fe(III)-bearing magnesium silicate glasses for applications in supplementary cementitious materials. Manuscript submitted for publication. Jiang, C., Santos, H. S., Ahmad, L., Yliniemi, J., Cheeseman, C., & Kinnunen, P. (2025). Properties of Fe-bearing Mg silicate glasses as novel supplementary cementitious materials. Manuscript submitted for publication. Tiivistelmä Jo vuosikymmenten ajan sementin seosaineita (SCM) on käytetty klinkkerin korvikkeina tavoitteena vähentää portlandsementin tuotannossa syntyviä CO2-päästöjä. Perinteisten SCM-materiaalien, kuten lentotuhkan, silikajauheen ja masuunikuonan, saatavuus ei kuitenkaan riitä mahdollistamaan korkeaa klinkkerin korvausastetta. Siksi on tarpeen kehittää uusia SCM-materiaaleja markkinoiden tarpeiden täyttämiseksi. Synteettiset lasit voivat olla potentiaalinen vaihtoehto niiden potsolaanisen aktiivisuuden ja säädettävien ominaisuuksien ansiosta. Lasien kemiallinen koostumus määrittää niiden potsolaanisen aktiivisuuden, ja enimmäkseen on tutkittu Ca-pohjaisia laseja niiden korkean reaktiivisuuden vuoksi. Tämä johtaa kuitenkin samoihin luontaisiin CO2-päästöihin kuin sementin tuotannossa, koska CaO:ta tuotetaan CaCO3:sta. Tämä väitöskirja tutkii Mg-pohjaisia silikaattilaseja, jotka tuotetaan sol-gel-menetelmällä, jossa lasien koostumusta säädetään korkeamman potsolaanisen aktiivisuuden saavuttamiseksi. Mg-pohjaisten silikaattilasien käyttökelpoisuutta SCM-materiaaleina tutkittiin kolmen pääasiallisen lähestymistavan kautta: (1) Binaarisen Mg-Si sol-gel-lasin kehitys: Eri Mg-pitoisuuksien vaikutuksia lasin reaktiivisuuteen arvioitiin (julkaisu I). (2) Fe:n lisääminen Mg-Si-järjestelmään: Mg-Si-laseihin lisättiin eri pitoisuuksia Fe3+/Fe2+:aa, ja niiden vaikutusta reaktiivisuuteen tutkittiin (julkaisut II, III). (3) Sementtimäisen suorituskyvyn arviointi: Mg-pohjaisten lasien potsolaanista aktiivisuutta arvioitiin, ja niiden vaikutusta seostettujen sementtien ominaisuuksiin ja suorituskykyyn tutkittiin (julkaisu IV). Tutkimus paljastaa synteettisten lasien korkean alkuaineliukoisuuden, mikä viittaa niiden korkeaan reaktiivisuuteen, sekä osoittaa, että niiden potsolaaninen aktiivisuus ylittää perinteiset SCM:t, kuten lentotuhkan ja kuonan. Nämä havainnot tarjoavat alustavan arvion Mg-silikaattilasien potentiaalista uusina SCM-materiaaleina, joiden tavoitteena on CO2-päästöjen vähentäminen. Osajulkaisut Jiang, C., Ramteke, D. D., Li, J., Sliz, R., Sreenivasan, H., Cheeseman, C., & Kinnunen, P. (2023). Preparation and characterization of binary Mg-silicate glasses via Sol-Gel route. Journal of Non-Crystalline Solids, 606, 122204. https://doi.org/10.1016/j.jnoncrysol.2023.122204 https://doi.org/10.1016/j.jnoncrysol.2023.122204 Rinnakkaistallennettu versio Jiang, C., Santos, H. S., Yliniemi, J., Lindén, J., Ramteke, D. D., Illikainen, M., Cheeseman, C., & Kinnunen, P. (2024). Fe-bearing magnesium silicate glasses for potential supplementary cementitious applications. Frontiers in Materials, 11, 1509403. https://doi.org/10.3389/fmats.2024.1509403 https://doi.org/10.3389/fmats.2024.1509403 Rinnakkaistallennettu versio Jiang, C., Yliniemi, J., Santos, H. S., Lindén, J., Ramteke, D.D., Cheeseman, C., & Kinnunen, P. (2024). Optimizing Fe(II)/Fe(III)-bearing magnesium silicate glasses for applications in supplementary cementitious materials. Manuscript submitted for publication. Jiang, C., Santos, H. S., Ahmad, L., Yliniemi, J., Cheeseman, C., & Kinnunen, P. (2025). Properties of Fe-bearing Mg silicate glasses as novel supplementary cementitious materials. Manuscript submitted for publication. Academic dissertation to be presented with the assent of the Doctoral Programme Committee of Technology and Natural Sciences of the University of Oulu for public defence in the Wetteri auditorium (IT115), Linnanmaa, on 25 April 2025, at 12 noonAbstract For decades, supplementary cementitious materials (SCMs) have been utilized as clinker substitutes as one of the strategies to mitigate the CO2 emissions associated with Portland cement production. However, traditional SCMs (e.g., coal fly ash, silica fume, and blast furnace slag) are being phased out, as they are insufficient to enable high volume clinker substitution. Therefore, alternative SCMs are actively being sought to meet market demand. Synthetic glasses may be a potential source of SCMs due to their pozzolanic activity and tunable properties. The chemical composition of glasses determines their pozzolanic activity, with Ca-based glasses being predominantly studied owing to their high reactivity. However, this leads to the same inherent CO2 emissions as for cement, originating from the production of CaO from CaCO3. This thesis investigates Mg-based silicate glasses synthesized via the sol-gel method, tuning their composition for higher pozzolanic activity. The feasibility of using Mg-based silicate glasses as SCMs was studied through three main pathways: (1) Development of a binary Mg-Si sol-gel glass system: The impact of varying Mg concentrations on the glass reactivity was assessed (Publication Ⅰ). (2) Introduction of Fe into the Mg-Si system: Varying concentrations of Fe3+/ Fe2+ were incorporated into Mg-Si glasses, investigating changes in reactivity (Publications Ⅱ, Ⅲ). (3) Assessment of cementitious performance: The pozzolanic activity of Mg-based glasses was evaluated, and their impact on the properties and performance of cementitious systems was studied (Publication Ⅳ). The research revealed the high elemental solubility of the synthetic glasses, indicating their high reactivity, and demonstrated pozzolanic activity exceeding that of conventional SCMs such as fly ash slag. These findings provide a preliminary assessment of the potential for using Mg silicate glasses as novel SCMs with the aim of reducing CO2 emissions.Tiivistelmä Jo vuosikymmenten ajan sementin seosaineita (SCM) on käytetty klinkkerin korvikkeina tavoitteena vähentää portlandsementin tuotannossa syntyviä CO2-päästöjä. Perinteisten SCM-materiaalien, kuten lentotuhkan, silikajauheen ja masuunikuonan, saatavuus ei kuitenkaan riitä mahdollistamaan korkeaa klinkkerin korvausastetta. Siksi on tarpeen kehittää uusia SCM-materiaaleja markkinoiden tarpeiden täyttämiseksi. Synteettiset lasit voivat olla potentiaalinen vaihtoehto niiden potsolaanisen aktiivisuuden ja säädettävien ominaisuuksien ansiosta. Lasien kemiallinen koostumus määrittää niiden potsolaanisen aktiivisuuden, ja enimmäkseen on tutkittu Ca-pohjaisia laseja niiden korkean reaktiivisuuden vuoksi. Tämä johtaa kuitenkin samoihin luontaisiin CO2-päästöihin kuin sementin tuotannossa, koska CaO:ta tuotetaan CaCO3:sta. Tämä väitöskirja tutkii Mg-pohjaisia silikaattilaseja, jotka tuotetaan sol-gel-menetelmällä, jossa lasien koostumusta säädetään korkeamman potsolaanisen aktiivisuuden saavuttamiseksi. Mg-pohjaisten silikaattilasien käyttökelpoisuutta SCM-materiaaleina tutkittiin kolmen pääasiallisen lähestymistavan kautta: (1) Binaarisen Mg-Si sol-gel-lasin kehitys: Eri Mg-pitoisuuksien vaikutuksia lasin reaktiivisuuteen arvioitiin (julkaisu I). (2) Fe:n lisääminen Mg-Si-järjestelmään: Mg-Si-laseihin lisättiin eri pitoisuuksia Fe3+/Fe2+:aa, ja niiden vaikutusta reaktiivisuuteen tutkittiin (julkaisut II, III). (3) Sementtimäisen suorituskyvyn arviointi: Mg-pohjaisten lasien potsolaanista aktiivisuutta arvioitiin, ja niiden vaikutusta seostettujen sementtien ominaisuuksiin ja suorituskykyyn tutkittiin (julkaisu IV). Tutkimus paljastaa synteettisten lasien korkean alkuaineliukoisuuden, mikä viittaa niiden korkeaan reaktiivisuuteen, sekä osoittaa, että niiden potsolaaninen aktiivisuus ylittää perinteiset SCM:t, kuten lentotuhkan ja kuonan. Nämä havainnot tarjoavat alustavan arvion Mg-silikaattilasien potentiaalista uusina SCM-materiaaleina, joiden tavoitteena on CO2-päästöjen vähentäminen

    Ribonucleotide reductase in dividing cells: Purification and inhibition studies with 4-hydroxynonenal

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    This thesis was submitted for the degree of Doctor of Philosophy and was awarded by Brunel University.1). The effect of temperature, P450 inhibitors (pyrazole and imidazole), sulphydryl reagents (iodoacetamide and N-ethyl maleimide) and glutathione on the activation of CCl4 in rat liver microsomes was studied. Spin trapping of CCI3', covalent binding of CCl4 to protein and CCl4-dependent MDA formation were used as indices of CCl4 metabolism. Formation of PBN-CCI3' adduct, 14CCl4 covalent binding to protein and CCl4-dependent :MDA production were dependent on temperature range from 15-40°C. The transition temperature was at 26.7 -27 .5°C when the activation was measured by formation of PBNCCl3' adduct and specific 14CCl4 covalent binding. The transition temperature was found to be 34.3°C when CCl4 -dependent MDA production was taken as the index of the activation of CCI4. Pyrazole, imidazole and iodoacetamide inhibited CC14 -dependent MDA formation only at high concentrations (10-20 mM), whereas glutathione showed a strong inhibitory effect on CCl4-stimulated lipid peroxidation. MDA formation was nearly 100°;6 inhibited by 1 roM GSH. GSH also delayed the onset of lipid peroxidation. N-ethyl maleimide (NEM) exerted biphasic effects on CCl4 -dependent MDA formation. The lower concentration of NEM (0.5 mM-l mM) reduced the :MDA prodUction, while the higher concentration of NEM (5-10 mM) enhanced the MDA formation. 2). Ribonucleotide reductase was partially purified from juvenile normal rat liver. The enzyme was purified 30 fold after DEAE-cellulose chromatography. The CDP reductase activity in tissues with different growth states or rates was compared. The enzyme activity was developed well in juvenile rat liver, regenerating liver and hepatoma (cells), while the enzyme activity was undetectable in adult rat liver and sham-operated rat liver. The enzyme activity in Yoshida cells was 3-fold of the activity in Morris 5123tc tumours. Dithiothreitol (DIT) activated the activity of CDP reductase from 48h and 60h regenerating liver, but DIT did not activate the enzyme activity of juvenile 'normal rat liver. The possible mechanism of the activation of enzyme activity by DIT was discussed and a mechanism of regulation of the ribonucleotide reductase activity in regenerating liver was suggested. 3). The effect of the lipid peroxidation product 4-hydroxynonenal (HNE) on CDP reductase from juvenile normal rat liver was investigated. HNE inhibited the CDP reductase activity. The inhibition was dependent on the concentration of HNE and the incubation time. The enzyme activity was reduced 500/0 by 0.1 roM HNE. The inhibitory effect of HNE was irreversible. DIT protected the enzyme against HNE suggesting that HNE inhibited the activity of ribonucleotide reductase from rat liver through the mechanism of blockage of functional SH groups in the enzyme protein

    Population Ecology of Thelymitra matthewsii Cheeseman Orchidaceae, in Northern New Zealand

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    The terrestrial orchid Thelymitra matthewsii Cheeseman, uncommon in New Zealand, was studied to increase knowledge of the species life cycle, morphology and ecology. Results will enhance future conservation management for the species. New information related to the morphology of T. matthewsii was obtained. The species was found to emerge in one of four discrete life stages of distinctive morphology and height range that remained constant for the season, not developing into a more advanced life stage. The leaf of the three pre adult life stages designated a hook, a spiral, and a non flowering stage, did not inflate at the base, but rose smoothly from the tuber. Apparent morphological differences in the column between descriptions of the Australian taxon and the small New Zealand sample examined suggested further study was needed. Comprehensive monthly monitoring was carried out at five study sites in three locations in the Te Paki area of the Far North, from 2002 to 2004. No patterns emerged in plant life stage succession, flowering, and presence or absence at labels reinforcing the concept that variability was a common component of the population census. Seasonal and partial absence was a major component of the populations. An average of 32.8% of plants, over five study sites, were present throughout three seasons, while 66.9% were recorded as absent (not visible) at monitoring. New plants appearing in 2003 and 2004 showed a high percentage of subsequent absence (mean 85.7%). To determine population stability, recruitment and absence were compared. Plant absence exceeded recruitment by 7% (mean plant absence 30.5%; mean recruitment 23.4%). Plants continued to appear during the monitoring period, and labeled plants increased two-fold over commencement numbers. Adults recorded as 28% of labeled plants over three seasons, were out numbered by pre-flowering stages. Only 5% of population numbers exhibited succession from a smaller to a flowering plant. Life stage modeling indicated a life stage was more likely to be followed by the same stage than an expected successive stage. Thelymitra matthewsii was found to be present in four substrates in the Far North. The survey of vegetation found the indigenous species Kunzea ericoides and the exotic Hakea gibbosa dominant for both height, and cover. Litter and bare ground dominated ground cover. Differences in vegetation and ground cover, of sites supporting T. matthewsii and comparison sites that did not, were minor and suggested that another factor, for example a suitable fungal partner, influenced the species presence or absence. The results of the study indicated the present threat classification of Thelymitra matthewsii is inadequate in the light of the species relatively circumscribed, widely separated habitats, the small number of reproducing individuals and vulnerability to habitat modification

    Erratum to: Effect of moderate red wine intake on cardiac prognosis after recent acute myocardial infarction of subjects with Type 2 diabetes mellitus (Diabetic Medicine, (2006), 23, 9, (974-981), 10.1111/j.1464-5491.2006.01886.x)

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    In an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola.In an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    De Maiestate / Praeside M. Jacobo Thomasio, Moralis Philosoph. P. P., publice disputabit Johannes Dunte, R. L. Author & Respon: ad diem 9. Septembr. H L. Q. C.

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    DE MAIESTATE / PRAESIDE M. JACOBO THOMASIO, MORALIS PHILOSOPH. P. P., PUBLICE DISPUTABIT JOHANNES DUNTE, R. L. AUTHOR & RESPON: AD DIEM 9. SEPTEMBR. H L. Q. C. De Maiestate / Praeside M. Jacobo Thomasio, Moralis Philosoph. P. P., publice disputabit Johannes Dunte, R. L. Author & Respon: ad diem 9. Septembr. H L. Q. C. (1) Titelblatt (1) Widmung (2) Text (3) Beiträge (21

    Survival of Salmonella typhimurium, Listeria monocytogenes and indicator bacteria on cooked uncured turkey loaf stored under vacuum at 3°C

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    Sterile slices of cooked uncured turkey loaf were inoculated with 106 CFU of either Salmonella typhimurium, Listeria monocytogenes, Escherichia coli, Enterococcus faecalis, Citrobacter freundii, Klebsiella pneumoniae, or Enterobacter cloacae. Inoculated samples were vacuum‐packaged and stored at 3 ± 1°C. Microorganisms were enumerated at 0, 3, 6, 9, 12, and 15 days on nonselective media. K. pneumoniae exhibited the least cold‐tolerance with a log10 1.70 decrease in numbers. The coliforms E. cloacae, E. coli, and C. freundii had a survival pattern similar to that of S. typhimurium, with population decreases of log10 0.65, 0.82, 1.13, and 0.79, respectively. E. faecalis and L. monocytogenes were significantly more cold‐resistant, with a decrease of log10 0.20 and no significant change in numbers, respectively. Survival of E. faecalis was not significantly (p < 0.01) different than that of L. monocytogenes, suggesting the use of enterococci as indicators of L. monocytogenes contamination of processed meats.Peer reviewedfinal article publishe

    Mechanical and thermal properties of lightweight geopolymer composites

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    This research has investigated the properties of thermally insulating geopolymer composites that were prepared using waste expanded polystyrene as lightweight aggregate. The geopolymer matrix was synthetized using metakaolin and an alkaline activating solution. To improve its mechanical properties, this matrix was modified by the addition of an epoxy resin to form an organic-inorganic composite. Moreover, in order to reduce drying shrinkage marble powder was used as an inert filler. The materials obtained were characterized in terms of physico-mechanical properties, thermal performance and microstructure. The geopolymer expanded polystyrene composite have improved properties compared to Portland cement-based materials, with higher strengths and lower thermal conductivity. The research demonstrates the manufacture of sustainable lightweight thermally insulating geopolymer composites using waste expanded polystyrene

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods
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