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Genetic diversity of the family Acipenseridae in Croatia
No full textAcipenseridae su uz porodicu Polyodontidae jedini živi predstavnici reda Acipenseriformes. One su među najprimitivnijim ribama koštunjačama te ujedno i zadnji preživjeli predstavnici gotovo potpuno izumrlog nadreda zrakoperki - Chondrostei, tzv. štitonoša. Razni antropogeni pritisci, ali i njihova relativna ekološka osjetljivost, doveli su Acipenseridae u prirodi u vrlo nepovoljan položaj te ih brojne zemlje počinju štititi. Na području Hrvatske, kroz prošlost je zabilježeno 8 vrsta iz porodice Acipenseridae te 1 vrsta iz porodice Polyodontidae, od kojih samo 2 vrste trenutno opstaju u prirodi te su obje klasificirane u ugrožene kategorije prema IUCN-u. Biologija porodice Acipenseridae na našim prostorima nije dovoljno istražena, što predstavlja značajan problem u zaštiti ovih vrsta. Uvid u taksonomsku i gensku raznolikost ovih vrsta kao i njihovu rasprostranjenost prvi je korak prema razvoju daljnjih istraživanja koja će omogućiti njihovu zadovoljavajuću zaštitu. U ovom istraživanju korištene su metode molekularne analize genskog markera citokrom b na uzorcima jedinki jesetre i kečige iz divljine i uzgajališta. Napravljene su rekonstrukcije filogenetskog stabla metodama najveće parsimonije i najveće vjerojatnosti, rekonstrukcija filogenetske mreže metodom susjednog povezivanja, kao i rekonstrukcija stabla evolucijske prošlosti bayesovom metodom. Također su izračunate mjere genske raznolikosti. Rezultati potvrđuju pripadnost uzorkovanih jedinki vrstama Acipenser ruthenus i A. baerii te ukazuju na zamjetnu razliku u stupnju genetske raznolikosti između populacija iz prirode i onih iz uzgajališta.With the family Polyodontidae, Acipenseridae are the only living members of the order Acipenseriformes. They are amongst the most primitive bony fish and are also the last surviving members of the almost extinct superorder of Actinopterygii - Chondrostei. Different anthropogenic pressures, in combination with their relatively high ecological vulnerability, have led Acipenseridae to a quite unfavorable position, so most countries have started implementing measures for their protection. Historically, there have been 8 recorded species from the family Acipenseridae and 1 from the family Polyodontidae in Croatia, of which only 2 still exist in the wild, both being classified in endangered IUCN categories. The biology of Acipenseridae in Croatia isn't researched enough, which poses a problem in conservation efforts. Gaining insights into their taxonomic and genetic diversity and geographic distribution is the first step for conducting research which will lead to adequate protection of these endangered species. This research uses methods of molecular analysis of the gene marker cytochrome b on species of sterlet and sturgeon captured in the wild and from a fishery. Reconstructions of phylogenetic trees using maximum parsimony and maximum likelihood methods, as well as a reconstruction of their phylogenetic network using mutual joining method and a reconstruction of their evolutionary history using Bayesian methods were made. Measures of their genetic diversity were also calculated. The results confirm that the sampled individuals belong to Acipenser ruthenus and A. baerii species and indicate a much higher degree of genetic diversity of wild populations in comparison to populations bred in fisheries
Mass extinctions and biodiversity
Get PDFU ovom završnom seminaru navedena su sva izumiranja u geološkoj povijesti Zemlje.
Iznesen je i pregled događaja u svakom izumiranju te dokazi koji ih potvrđuju. Pregled
događaja obuhvaća uzroke i posljedice izumiranja te skupine organizama najviše pogođene
svakim izumiranjem.This final seminar mentions every mass extinction in the geological history of Earth.
There is also an overview of important events in each mass extinction accompanied by
evidence. The overview encompasses causes and effects of each extinction event in addition to
groups of organisms that were affected the hardest
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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