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Bilirkisi Raporu vb., Pagou Kalliopi,Dorgham Mohamed,EDIGER DILEK,Precali Robert (2015). Eutrophication. UNEP (DEPI)/MED WG 411/ınf.9 (Yayın No: 2537418)
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Importance, biodiversity and dynamics of coccolithophorids in the coastal area of the north-east Adriatic sea
Get PDFDijatomeje, dinoflagelati i kokolitoforidi su najvažnije fitoplanktonske skupine u obalnim morima, od kojih je posljednja najslabije istražena u Jadranu. Iako je za sjeverni Jadran u literaturi zabilježeno 86 vrsta kokolitoforida, redovito ih se zamjećuje tek 16. Sukladno novim spoznajama o složenosti njihovog životnog ciklusa, potrebita je revizija njihove bioraznolikosti te ekološkog značaja u Jadranu. Uzorci za analizu fitoplanktonske zajednice i popratnih fizičko-kemijskih čimbenika sakupljani su mjesečno tijekom 2008. i 2009. godine duž zapadne obale Istarskog poluotoka. Za dodatne analize fotosintetskih pigmenata i kokolitoforida uzorkovano je svakih deset dana. Tijekom studija zabilježeno je ukupno 52 taksona kokolitoforida, a dominirao je rod Syracosphaera, sa zastupljenih 13 vrsta. Kokolitoforidi heterofaze (HET) i holofaze (HOL) bili su prisutni tijekom cijelog istraživanog razdoblja, a sezonalnost HET/HOL faze primijećena je za Coronosphaera mediterranea (jesen)/ HOL Calyptrolithina wettsteini (proljeće) i Syracosphaera pulchra (ljeto)/ HOL Calyptrosphaera oblonga (proljeće). Analiza pigmenata ukazuje na dominaciju 19'-heksanoilofukoksantina, pigmenta svojstvenog za haptofite. Visoke koncentracije tog pigmenta zabilježene su tijekom cijele godine s najvišim vrijednostima u kasno proljeće. Razdoblje proljeća (ožujak - lipanj) obilježila je visoka raznolikost vrsta i veći doprinos kokolitoforida ukupnoj fitoplanktonskoj zajednici (> 60%). Brojnost kokolitoforida Rhabdosphaera clavigera i Syracosphaera pulchra, značajno je povezana s visokim temperaturama i niskim koncentracijama nitrata, što je uobičajeno za ljetne mjesece. Nasuprot, brojnost vrsta Calciosolenia murrayi i C. brasiliensis značajno je bila povezana s povišenim koncentracijama hranjivih soli, te je njihov razvoj bio karakterističan za jesensku fitoplanktonsku zajednicu. Navedene vrste su se pokazale uspješnim kompetitorima s dijatomejama koje su inače dominirale fitoplanktonskom zajednicom. Najbrojnija je bila vrsta Emiliania huxleyi (106 stanica L-1 ), tijekom monospecifičnog cvata (92% od ukupnog fitoplanktona) u siječnju. E. huxleyi je najčešći kokolitoforid, povezan s niskim temperaturama i visokim koncentracijama hranjivih soli, prisutan u velikom broju i zimi i ljeti.Diatoms, dinoflagellates and coccolithophorids are the most important groups in the marine phytoplankton community. Studies of coccolithophorid taxonomy and ecology in the Adriatic are scarce, unlike those on diatoms and dinoflagellates. Although 86 species of coccolithophorids were reported for the northern Adriatic, only 11 species are regularly recorded. A revision of coccolithophorid biodiversity and their ecological importance in the Adriatic was necessary due to new insights on the life cycles of species. This study was conducted during one year (2008 2009) and samples were collected every ten days in the coastal area in front of Rovinj. The research was completed using light and electron microscopic examinations together with pigment analysis by high-performance liquid chromatography. A total of 52 coccolithophore morphospecies were recorded during the study. Dominating genus was Syracosphaera, represented by 13 species. Coccolithophorids of both diploid (HET) and haploid (HOL) phases were present throughout the investigated period. Seasonality in HET/HOL phases was observed for Syracosphaera pulchra (summer)/ HOL Calyptrosphaera oblonga (spring) and Coronosphaera mediterranea (autum)/ HOL Calyptrolithina wettsteini (spring). Pigment analysis pointed to a clear domination of 19-hexanoyloxyfucoxanthin, the pigment characteristic for haptophytes. High concentrations of 19-hexanoyloxyfucoxanthin were recorded throughout the year with a distinct peak in the spring. The spring period (March - June) was characterised by a high species diversity and higher contribution of coccolithophorids to the total phytoplankton assemblage (>60%). The typical summer coccolithophores, Rhabdosphaera clavigera and Syracosphaera pulchra, were related to high temperatures and low nitrate concentrations. Coccolithophorids Calciosolenia murrayi and C. brasiliensis were related to elevated nutrient concentrations, and were characteristic for the autumn assemblage. They were able to find favourable living conditions despite the abundant occurrence of diatoms and low light transmission values. Highest abundances of the species Emiliania huxleyi (106 cells L-1 ) were recorded in January during a monospecific bloom (92% of whole phytoplankton community). E. huxleyi was the most frequently recognised species and was related to low temperature and nutrient rich waters, consequently present in high numbers both during winter and summer
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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