1,720,992 research outputs found
Three new species of Enhydrosoma and a new record of Enhydrosoma lacunae (Copepoda : Harpacticoida : Cletodidae) from the Eastern Tropical Pacific
No full textA number of harpacticoid copepods were collected during two series of sampling campaigns in a coastal lagoon and in a brackish system in northern and southern Sinaloa (northwestern Mexico), respectively. Four enhydrosomid species were recognized. Three of them are new to science. Enhydrosoma lacunae is reported for the sixth time. This record extends the distribution of the species from the Caribbean Sea to the Eastern Tropical Pacific, and it is suggested that it is an invasive species home in water ballast of ships. Enhydrosoma parapropinquum sp. nov. bears a strong resemblance to E. propinquum, but these species are different in shape of the caudal rami and female fifth leg. Enhydrosoma casoae sp. nov. and E. solitarium sp. Boy. showed to be closely related to E. vicinum. These three species seem to be related by the structure and armature formula of the female fifth swimming leg. Enhydrosoma casoae sp. nov. and Enhydrosoma solitarium sp. nov. can be separated from each other by the ventral spinular ornamentation of urosome and spinular ornamentation of female P5 baseoendopod
Three new species of Enhydrosoma and a new record of Enhydrosoma lacunae (Copepoda : Harpacticoida : Cletodidae) from the Eastern Tropical Pacific
No full textA number of harpacticoid copepods were collected during two series of sampling campaigns in a coastal lagoon and in a brackish system in northern and southern Sinaloa (northwestern Mexico), respectively. Four enhydrosomid species were recognized. Three of them are new to science. Enhydrosoma lacunae is reported for the sixth time. This record extends the distribution of the species from the Caribbean Sea to the Eastern Tropical Pacific, and it is suggested that it is an invasive species home in water ballast of ships. Enhydrosoma parapropinquum sp. nov. bears a strong resemblance to E. propinquum, but these species are different in shape of the caudal rami and female fifth leg. Enhydrosoma casoae sp. nov. and E. solitarium sp. Boy. showed to be closely related to E. vicinum. These three species seem to be related by the structure and armature formula of the female fifth swimming leg. Enhydrosoma casoae sp. nov. and Enhydrosoma solitarium sp. nov. can be separated from each other by the ventral spinular ornamentation of urosome and spinular ornamentation of female P5 baseoendopod
Systematics and some data on the ecology of the harpacticoid fauna (copepoda, harpacticoida) from a subtropical coastal lagoon in the South-Eastern Gulf of California(Mexico)
No full textOm het beheer van de kust-ecosystemen in noordwest Mexico te verbeteren, werd in 1990 een onderzoek gestart naar de biologische, scheikund1ge en fysische aspecten van deze aquat1sche systemen. Een van de te bestuderen systemen was de Alrara-Ensenada del Pabel/6n lagune (Sinaloa, Mexico), waarvan de benthische gemeenschappen geanalyseerd werden door de onderzoeksgroep Benthische lnvertebraten van hetlnstituto de Ciencias del Mary Limnologia, Estaci6n Mazatlan (ICMyLUNAM). Tot de studie van de benthische gemeenschappen behoorde ook de analyse van de verspreiding en densiteit van de meiofauna, waarvan tot voorheen geen gegevens beschikbaar waren voor de Mexicaanse westkust. Uit deze stud1c blcck de numerieke dominantic van de harpacticoiden die, na de Nematoda, het belangrijkste venegenwoordigende taxon vormden. Om de studie van de harpacticoidenfauna , tot op heden onbekend van de Mexicaanse westkust, verder te zenen, werd in 1995 gestan met een grondige studie van de systernatiek en de ecologic van deze groep. Deze studie vormt het belangrijkste dee! van de hier voorgelegde verhandehng. Nauwkeurige identificatie en gedetailleerde beschrijving van de verzamelde harpacticoiden bracht het totaal van aanwezige families op 20 met 63 geidentificeerde soonen, waarvan 57% nieuw zijn voor de wetenschap. Verder werd de ondersoon Longipedia helgolandica santacruzensis Mielke verheven tot op soonsniveau, Long1pedia santacro:ensis Mielke comb. nov. Eoschizopera (Praeoschizopera) indica Rao & Ganapati werd overgebracht naar het geslacht Eoschizopera (s. str.). Eoschizopera spec. B Mielke 1995 werd ondergebracht in Eoschizopera (Praeoschizopera). Schizopera osana Mielke en Schizopera spec. A M1elke 19995a werden overgebracht naar een nieuw subgenus, hier gedefinieerd Van Pseudosrenhelia we/lsi Coull & Fleeger werd een volledige herbesehrijving gegeven, en het Mexicaans materiaal werd grondig vergeleken met specimens atkomstig van de typestreek. Op basis van deze gegevens werd de chaetotaxie van de poten zoals die werd voorgesteld door Coull &Fleeger (1972), Wells (1967) en Ranga & Reddy (1984), aangepast. In hoofdstuk V wordt een kone bespreking gegeven van de tot nu toe meest relevante biogeografische modellen voor meiofauna. Bovendien wordt een kone biogeografische analyse gegeven van het genus Scouolana (Canuellidae) en een soonsgroep in het genus Longipedia (Longipediidae). Dit wordt voorgesteld in de vorm van werkhypothesen die in de toekomst getest moeten worden. De densiteits- en verspreidingsanalyse van de harpacticoiden in Ensenada del Pabel/6n lagune werd reeds elders gepubhceerd (G6mez Noguera & Hendrickx, 1997), b1jgevolg worden hier slechts enkele aantekeningen gemaakt. Tenslotte wordt een biodiversiteitsanalyse van 4 gemeenschappen besproken. Na grondig onderzoek werd vooropgesteld dat de biodiversiteit van de harpacticoidengemeenschappen van de vier stations negauef beinvloed worden door organisehe aanrijking, afkornsllg van agro-industnele activueiten m het noordoostelijke dee! van het systeem
To 1mprove the management of the coastal ecosystems in Nonh-~estem Me~1co, a study on the b1ology, chemistry and phys1cal propen1es of these 1mponant aqu1fers was mltiated in 1990 One of the systems to be stud1ed in deta1l was the Altara-Ensenada del Pabel/6n lagoon (Smaloa, Me,..ICO), whose benthic commumues were analized by the Benthic Invertebrates Research Group of the /nsriruro de Ctencias del Mary Limnologia, Esraci6n Mazarlim (ICMyL-UNAM) The study of the benthic commumues involved the analysis of the distnbution and abundance of meiofauna, of wh1ch no data ~ere available for the Mexican Pac1fic coast. From th1s study, the numeric dominance of harpacticoids, only outnumbered by the nematodes, was observed In order to continue the analys1s of harpacuc01ds, unknown from the MeAICan Pacific coast so far, and mdepth study on its systematics and ecology staned in 1995, and constitutes the main body of the present thesis. Detailed comparison and careful descnpuon of the encountered harpactico1ds revealed the presence of 20 families. In total 63 spec1es were identified, of which 57~o are new to sc1ence. In addition, the subspecies Long1pedia he/go/andica sanracro:ensis Mielke is ra1sed to the species rank, Longipedia santacmzensis Mielke comb. nov .. Eoschizopera (Praeoschizopera) indica Rao & Ganapati is transferred to Eoschizopera (s. srr.), while Eoschi::opera spec. B Mielke 1995 is allocated to Eoschizopera (Praeoschizopera), and Sch1zopera osana Mielke and Schizopera spec. A Mielke 1995a are attributed to a new subgenus, here defined Pseudostenhe/ia we/lsi Coull & Fleeger IS fully redescribed and compared with specimens from the type-region. Based on these observations, the setal formula of the natatorial legs as was presented by Coull & Fleeger ( 1972), Wells ( 1967) and Ranga & Reddy ( 1984) is amended. In chapter V, a brief discussion of the most relevant biogeographic models of meiofauna is presented Additionally, a brief biogeographic analysis of a spec1es-group of the genus Longipedia (Longipediidae) and the genus Scouo/ana (Canuellidae) have been included under the form of work hypotheses which should be tested in future studies. The analysis of abundance and distribution of harpacticoids in Ensenada del Pabel/6n lagoon have been presented elsewhere (G6mez Noguera & Hendrickx, 1997). Only some additional comments are included herein. Finally, the analysis of the diversity of 4 communities is presented and discussed. It is concluded that the diversity of the harpacticoid communities in the four stations are negatively affected by organic enrichment through the sewage outlets of agro-indiustrial activities in the north-eastern pan of this ecosystem
Systematics and some data on the ecology of the harpacticoid fauna (copepoda, harpacticoida) from a subtropical coastal lagoon in the South-Eastern Gulf of California(Mexico)
No full textOm het beheer van de kust-ecosystemen in noordwest Mexico te verbeteren, werd in 1990 een onderzoek gestart naar de biologische, scheikund1ge en fysische aspecten van deze aquat1sche systemen. Een van de te bestuderen systemen was de Alrara-Ensenada del Pabel/6n lagune (Sinaloa, Mexico), waarvan de benthische gemeenschappen geanalyseerd werden door de onderzoeksgroep Benthische lnvertebraten van hetlnstituto de Ciencias del Mary Limnologia, Estaci6n Mazatlan (ICMyLUNAM). Tot de studie van de benthische gemeenschappen behoorde ook de analyse van de verspreiding en densiteit van de meiofauna, waarvan tot voorheen geen gegevens beschikbaar waren voor de Mexicaanse westkust. Uit deze stud1c blcck de numerieke dominantic van de harpacticoiden die, na de Nematoda, het belangrijkste venegenwoordigende taxon vormden. Om de studie van de harpacticoidenfauna , tot op heden onbekend van de Mexicaanse westkust, verder te zenen, werd in 1995 gestan met een grondige studie van de systernatiek en de ecologic van deze groep. Deze studie vormt het belangrijkste dee! van de hier voorgelegde verhandehng. Nauwkeurige identificatie en gedetailleerde beschrijving van de verzamelde harpacticoiden bracht het totaal van aanwezige families op 20 met 63 geidentificeerde soonen, waarvan 57% nieuw zijn voor de wetenschap. Verder werd de ondersoon Longipedia helgolandica santacruzensis Mielke verheven tot op soonsniveau, Long1pedia santacro:ensis Mielke comb. nov. Eoschizopera (Praeoschizopera) indica Rao & Ganapati werd overgebracht naar het geslacht Eoschizopera (s. str.). Eoschizopera spec. B Mielke 1995 werd ondergebracht in Eoschizopera (Praeoschizopera). Schizopera osana Mielke en Schizopera spec. A M1elke 19995a werden overgebracht naar een nieuw subgenus, hier gedefinieerd Van Pseudosrenhelia we/lsi Coull & Fleeger werd een volledige herbesehrijving gegeven, en het Mexicaans materiaal werd grondig vergeleken met specimens atkomstig van de typestreek. Op basis van deze gegevens werd de chaetotaxie van de poten zoals die werd voorgesteld door Coull &Fleeger (1972), Wells (1967) en Ranga & Reddy (1984), aangepast. In hoofdstuk V wordt een kone bespreking gegeven van de tot nu toe meest relevante biogeografische modellen voor meiofauna. Bovendien wordt een kone biogeografische analyse gegeven van het genus Scouolana (Canuellidae) en een soonsgroep in het genus Longipedia (Longipediidae). Dit wordt voorgesteld in de vorm van werkhypothesen die in de toekomst getest moeten worden. De densiteits- en verspreidingsanalyse van de harpacticoiden in Ensenada del Pabel/6n lagune werd reeds elders gepubhceerd (G6mez Noguera & Hendrickx, 1997), b1jgevolg worden hier slechts enkele aantekeningen gemaakt. Tenslotte wordt een biodiversiteitsanalyse van 4 gemeenschappen besproken. Na grondig onderzoek werd vooropgesteld dat de biodiversiteit van de harpacticoidengemeenschappen van de vier stations negauef beinvloed worden door organisehe aanrijking, afkornsllg van agro-industnele activueiten m het noordoostelijke dee! van het systeem
To 1mprove the management of the coastal ecosystems in Nonh-~estem Me~1co, a study on the b1ology, chemistry and phys1cal propen1es of these 1mponant aqu1fers was mltiated in 1990 One of the systems to be stud1ed in deta1l was the Altara-Ensenada del Pabel/6n lagoon (Smaloa, Me,..ICO), whose benthic commumues were analized by the Benthic Invertebrates Research Group of the /nsriruro de Ctencias del Mary Limnologia, Esraci6n Mazarlim (ICMyL-UNAM) The study of the benthic commumues involved the analysis of the distnbution and abundance of meiofauna, of wh1ch no data ~ere available for the Mexican Pac1fic coast. From th1s study, the numeric dominance of harpacticoids, only outnumbered by the nematodes, was observed In order to continue the analys1s of harpacuc01ds, unknown from the MeAICan Pacific coast so far, and mdepth study on its systematics and ecology staned in 1995, and constitutes the main body of the present thesis. Detailed comparison and careful descnpuon of the encountered harpactico1ds revealed the presence of 20 families. In total 63 spec1es were identified, of which 57~o are new to sc1ence. In addition, the subspecies Long1pedia he/go/andica sanracro:ensis Mielke is ra1sed to the species rank, Longipedia santacmzensis Mielke comb. nov .. Eoschizopera (Praeoschizopera) indica Rao & Ganapati is transferred to Eoschizopera (s. srr.), while Eoschi::opera spec. B Mielke 1995 is allocated to Eoschizopera (Praeoschizopera), and Sch1zopera osana Mielke and Schizopera spec. A Mielke 1995a are attributed to a new subgenus, here defined Pseudostenhe/ia we/lsi Coull & Fleeger IS fully redescribed and compared with specimens from the type-region. Based on these observations, the setal formula of the natatorial legs as was presented by Coull & Fleeger ( 1972), Wells ( 1967) and Ranga & Reddy ( 1984) is amended. In chapter V, a brief discussion of the most relevant biogeographic models of meiofauna is presented Additionally, a brief biogeographic analysis of a spec1es-group of the genus Longipedia (Longipediidae) and the genus Scouo/ana (Canuellidae) have been included under the form of work hypotheses which should be tested in future studies. The analysis of abundance and distribution of harpacticoids in Ensenada del Pabel/6n lagoon have been presented elsewhere (G6mez Noguera & Hendrickx, 1997). Only some additional comments are included herein. Finally, the analysis of the diversity of 4 communities is presented and discussed. It is concluded that the diversity of the harpacticoid communities in the four stations are negatively affected by organic enrichment through the sewage outlets of agro-indiustrial activities in the north-eastern pan of this ecosystem
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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