1,721,198 research outputs found
FIGURE 1 in A new species of Bosmina (Liederobosmina) Brték, 1997 (Cladocera: Bosminidae) from high mountain lakes of Colombia
No full textFIGURE 1. Bosmina (Liederobosmina) korineki sp.nov., A, large parthenogenetic female. B, juvenile female from Laguna Chisacá, Bogotá Province, Colombia. Photos by the confocal microscope. Scale bars 0.1 mm.Published as part of Garibian, Petr G., Juračka, Petr Jan & Kotov, Alexey A., 2021, A new species of Bosmina (Liederobosmina) Brték, 1997 (Cladocera: Bosminidae) from high mountain lakes of Colombia, pp. 280-290 in Zootaxa 4990 (2) on page 283, DOI: 10.11646/zootaxa.4990.2.4, http://zenodo.org/record/502640
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
Sladkovodní tůně bez ryb: od metaspolečenstev po systematiku
No full textFreshwater fishless pools: from the metacommunities to the systematics Petr Jan Juračka, Ph.D. Thesis, 2016-04-08 ABSTRAKT (in Czech) Sladkovodní tůně bez ryb mohou významně přispívat ke zvyšování regionálního druhového bohatství bezobratlých živočichů i cévnatých rostlin, neboť mnohdy i přes jejich spíše drobnou velikost obsahují značně složitá společenstva. Podstatná část této dizertační práce pramení právě z takových tůní, které byly pro účely ochrany přírody nově vytvořeny v rámci Chráněné krajinné oblasti Kokořínsko, známé svými hlubokými údolími a pískovcovými skalami. V kraji je rovněž velmi málo tekoucích vod či větších vodních ploch, následně je zde tedy i poměrně málo vodního ptactva, jež zásadně přispívá k šíření vodních organismů. V rámci této práce jsme se zaměřili na metaspolečenstva drobných korýšů vybraných 42 tůní z oblasti zhruba 220 km2 . Pomocí dekompozice variability druhového složení, analýzy druhového bohatství a kolonizačního pokusu přímo ve studované oblasti jsme zjistili, že prostorové uspořádání a množství okolních dalších vodních habitatů hrají hlavní roli v uspořádávání jednotlivých společenstev korýšů. To nás vedlo k závěru, že zdejší krajinná rozmanitost funguje jako omezení pro šíření korýšů mezi tůněmi. Následně jsme se rozhodli porovnat tyto výsledky s jinými bezobratlými...Freshwater fishless pools: from the metacommunities to the systematics Petr Jan Juračka, Ph.D. Thesis, 2016-04-08 ABSTRACT Despite their small size, freshwater fishless pools often contain complex communities and substantially increase regional invertebrate and macrophyte biodiversity. The main core of this thesis originates from such habitats, which were newly created for the conservation purposes in the Protected Landscape Area Kokořínsko, Czech Republic. This landscape consists of deep valleys separated by steep sandstone ridges and is characteristic for very sparse stream network and low number of large water habitats, which consequents in generally low abundance of waterfowl. We studied microcrustacean metacommunities of 42 selected pools scattered over the area of approximately 220 km2 . Using variation partitioning of the species composition, analyses of the species richness and colonization experiment in the study area, we identified that spatial distribution of the habitats and number of neighbouring aquatic habitats play a major role in assembly of local communities. This led us to the conclusion that the landscape heterogeneity served as a partial barrier to dispersal of microcrustaceans. Subsequently, we compared this pattern of the microcrustacean metacommunity with other invertebrates of...Katedra ekologieDepartment of EcologyFaculty of SciencePřírodovědecká fakult
Sladkovodní tůně bez ryb: od metaspolečenstev po systematiku
No full textFreshwater fishless pools: from the metacommunities to the systematics Petr Jan Juračka, Ph.D. Thesis, 2016-04-08 ABSTRACT Despite their small size, freshwater fishless pools often contain complex communities and substantially increase regional invertebrate and macrophyte biodiversity. The main core of this thesis originates from such habitats, which were newly created for the conservation purposes in the Protected Landscape Area Kokořínsko, Czech Republic. This landscape consists of deep valleys separated by steep sandstone ridges and is characteristic for very sparse stream network and low number of large water habitats, which consequents in generally low abundance of waterfowl. We studied microcrustacean metacommunities of 42 selected pools scattered over the area of approximately 220 km2 . Using variation partitioning of the species composition, analyses of the species richness and colonization experiment in the study area, we identified that spatial distribution of the habitats and number of neighbouring aquatic habitats play a major role in assembly of local communities. This led us to the conclusion that the landscape heterogeneity served as a partial barrier to dispersal of microcrustaceans. Subsequently, we compared this pattern of the microcrustacean metacommunity with other invertebrates of...Freshwater fishless pools: from the metacommunities to the systematics Petr Jan Juračka, Ph.D. Thesis, 2016-04-08 ABSTRAKT (in Czech) Sladkovodní tůně bez ryb mohou významně přispívat ke zvyšování regionálního druhového bohatství bezobratlých živočichů i cévnatých rostlin, neboť mnohdy i přes jejich spíše drobnou velikost obsahují značně složitá společenstva. Podstatná část této dizertační práce pramení právě z takových tůní, které byly pro účely ochrany přírody nově vytvořeny v rámci Chráněné krajinné oblasti Kokořínsko, známé svými hlubokými údolími a pískovcovými skalami. V kraji je rovněž velmi málo tekoucích vod či větších vodních ploch, následně je zde tedy i poměrně málo vodního ptactva, jež zásadně přispívá k šíření vodních organismů. V rámci této práce jsme se zaměřili na metaspolečenstva drobných korýšů vybraných 42 tůní z oblasti zhruba 220 km2 . Pomocí dekompozice variability druhového složení, analýzy druhového bohatství a kolonizačního pokusu přímo ve studované oblasti jsme zjistili, že prostorové uspořádání a množství okolních dalších vodních habitatů hrají hlavní roli v uspořádávání jednotlivých společenstev korýšů. To nás vedlo k závěru, že zdejší krajinná rozmanitost funguje jako omezení pro šíření korýšů mezi tůněmi. Následně jsme se rozhodli porovnat tyto výsledky s jinými bezobratlými...Department of EcologyKatedra ekologieFaculty of SciencePřírodovědecká fakult
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
FIGURE 3 in A new Central European species of the Daphnia curvirostris complex, Daphnia hrbaceki sp. nov. (Cladocera, Anomopoda, Daphniidae)
No full textFIGURE 3. Comparison of postabdominal claws. Arrows indicate second (middle) pecten of spinules or teeth of postabdominal claw. A. Daphnia hrbaceki, adult female (K). B. D. hrbaceki, adult female from laboratory culture (K). C. D. hrbaceki, adult female (RB). D. D. hrbaceki, adult female from laboratory culture (K); detail of middle pecten. E. D. hrbaceki, adult male from laboratory culture (K). F. Daphnia sp. (morphotype FLO9), adult female (FL). G. D. minnehaha, adult female (ELA).Published as part of Juračka, Petr Jan, Kořínek, Vladimír & Petrusek, Adam, 2010, A new Central European species of the Daphnia curvirostris complex, Daphnia hrbaceki sp. nov. (Cladocera, Anomopoda, Daphniidae), pp. 1-22 in Zootaxa 2718 on page 9, DOI: 10.5281/zenodo.19978
Freshwater fishless pools: from the metacommunties to the systematics
No full textFreshwater fishless pools: from the metacommunities to the systematics Petr Jan Juračka, Ph.D. Thesis, 2016-04-08 ABSTRACT Despite their small size, freshwater fishless pools often contain complex communities and substantially increase regional invertebrate and macrophyte biodiversity. The main core of this thesis originates from such habitats, which were newly created for the conservation purposes in the Protected Landscape Area Kokořínsko, Czech Republic. This landscape consists of deep valleys separated by steep sandstone ridges and is characteristic for very sparse stream network and low number of large water habitats, which consequents in generally low abundance of waterfowl. We studied microcrustacean metacommunities of 42 selected pools scattered over the area of approximately 220 km2 . Using variation partitioning of the species composition, analyses of the species richness and colonization experiment in the study area, we identified that spatial distribution of the habitats and number of neighbouring aquatic habitats play a major role in assembly of local communities. This led us to the conclusion that the landscape heterogeneity served as a partial barrier to dispersal of microcrustaceans. Subsequently, we compared this pattern of the microcrustacean metacommunity with other invertebrates of..
Freshwater fishless pools: from the metacommunties to the systematics
No full textFreshwater fishless pools: from the metacommunities to the systematics Petr Jan Juračka, Ph.D. Thesis, 2016-04-08 ABSTRACT Despite their small size, freshwater fishless pools often contain complex communities and substantially increase regional invertebrate and macrophyte biodiversity. The main core of this thesis originates from such habitats, which were newly created for the conservation purposes in the Protected Landscape Area Kokořínsko, Czech Republic. This landscape consists of deep valleys separated by steep sandstone ridges and is characteristic for very sparse stream network and low number of large water habitats, which consequents in generally low abundance of waterfowl. We studied microcrustacean metacommunities of 42 selected pools scattered over the area of approximately 220 km2 . Using variation partitioning of the species composition, analyses of the species richness and colonization experiment in the study area, we identified that spatial distribution of the habitats and number of neighbouring aquatic habitats play a major role in assembly of local communities. This led us to the conclusion that the landscape heterogeneity served as a partial barrier to dispersal of microcrustaceans. Subsequently, we compared this pattern of the microcrustacean metacommunity with other invertebrates of..
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