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Streptosyllis Webster & Benedict 1884
No full textGenus Streptosyllis Webster & Benedict 1884 Streptosyllis Webster & Benedict, 1844: 711. Streptosyllis - San Martín, 2003: 120. Streptosyllis - San Martín & Hutchings, 2006: 354–355. Type species: Streptosyllis arenae Webster & Benedict, 1884. Diagnosis: Body small. Four eyes, occasionally anterior pair of eyespots present. Palps fused at base, occasionally reduced to small papillae. Anterior parapodia with modified compound chaetae; sometimes with enlarged aciculae. Dorsal simple chaetae present, ventral simple chaetae absent. Compound chaetae homogomph or hemigomph, falcigerous, occasionally spinigerous. Dorsal cirri smooth, pseudoarticualated or articulated with granular inclusions. Ventral cirri digitiform, sometimes longer than parapodial lobe. Pharynx unarmed with crown of soft papillae. Pygidium with one median and two lateral anal cirri.Published as part of Faulwetter, Sarah, Vasileiadou, Aikaterini, Papageorgiou, Nafsika & Arvanitidis, Christos, 2008, Description of a new species of Streptosyllis (Polychaeta: Syllidae) from the Mediterranean and Canary Islands with a re-description of Streptosyllis arenae and comments on the taxonomy of Streptosyllis and some morphologically similar genera, pp. 1-18 in Zootaxa 1847 on page
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Streptosyllis arenae Webster & Benedict 1884
No full text<i>Streptosyllis arenae</i> Webster & Benedict 1884 <p>Figures 1–3</p> <p> <i>Streptosyllis arenae</i> Webster & Benedict, 1884: 711–713, Figures 17–23.</p> <p> <i>Streptosyllis arenae</i> - Pettibone, 1963: 127, Figures 31 l–m; - Hartmann-Schröder, 1996: 163.</p> <p> <b>Material examined:</b> 3 out of 5 paratypes USNM 417 labelled as <i>S. arenae</i> (holotype unavailable).</p> <p> <b>Type locality:</b> Provincetown, Cape Cod, Massachusetts, USA.</p> <p> <b>Habitat:</b> Sandy bottoms, shallow water.</p> <p> <b>Description:</b> (based on the paratype labelled 119/1717, fixed on slide): Body ca. 2.8 mm long, for 40 chaetigers; maximal width 300 µm without parapodial lobes, 440 µm with parapodial lobes and 570 µm including chaetae (5 th segment) (Figure 1). Head semi-circular, wider than long, anterior margin regularly rounded. Two pairs of eyes, one pair of eyespots, latter located near anterior margin (near eye spots). Three antennae present, each irregularly wrinkled, median antenna inserted between two pairs of lateral eyes in middle of prostomium, lateral antennae located near anterior margin of prostomium. Median antenna ca. 370 µm long, lateral ones ca. 120 µm. Palps form two rounded lobes, fused basally, outer margins prolonged into vestigial cirrus (Figure 2g). Palps directed ventrally, not visible dorsally. Peristomium indistinct, bearing two pairs of tentacular cirri, each about as long as lateral antennae. Dorsal cirri about same length as lateral antennae, some longer, generally shorter near posterior end. Shape and structure of dorsal cirri varies within same animal: either smooth, wrinkled, pseudo-articulated with granular rounded inclusions, articulated with each article divided longitudinally or articulated without divided articles (Figures 1, 2d–f). Ventral cirri slightly wrinkled, digitiform, wide at base, about length of parapodial lobe of first segments, then becoming longer, about twice length of parapodial lobe in posterior part and longer than dorsal cirri (Figures 2a–c). Pygidium with tiny median anal cirrus, lateral anal cirri not observed (Figure 1). Dorsal simple chaeta present from chaetiger 1, slightly curved, ca. 55 µm anteriorly, 90 µm posteriorly, tip bluntly rounded and covered by hyaline hood (Figures 3j–o). Up to ten hemigomph compound chaetae in each parapodium, length ca. 45 µm anteriorly, 85 µm posteriorly (Figures 2a–c). Shaft of compound chaetae ending in up to three rounded teeth (Webster and Benedict report four teeth, not observed in material examined), sometimes with notched tips. Blades of two kinds, longer ones (ca. 19 µm) in dorsal chaetae, shorter ones (ca. 12 µm) in ventral chaetae, becoming longer towards posterior end. In first five chaetigers only chaetae with short blades present (Figures 3p–s); from chaetiger 6 onwards, two long-bladed and 8–9 short-bladed chaetae per bundle present. Longer blades unidentate with rounded tip covered by halo-shaped hyaline hood, and small tooth near distal part (Figures 3t –v). Shorter blades with more acute tip and hood covering not only tip of blade but prolonged down to distal end of shaft. (Figure 3s). Aciculae distinctively enlarged on chaetigers 2–5, one per parapodium, each distally knobbed, terminating at tip of parapodial lobe (Figure 3a–i). Length of aciculae ca. 130 µm in anterior chaetigers, 190 µm in posterior chaetigers. Pharynx unarmed, extending from anterior end to chaetiger 3. Proventriculus extending through 6–7 segments, with about 56 muscle cell rows (Figure 1).</p> <p> <b>Character variation:</b> Length of median anal cirrus varies among paratypes: from very short to about as long as dorsal cirri.</p> <p> <b>Remarks:</b> Of the five individuals labelled as paratypes of <i>Streptosyllis arenae</i> (USNM 417), one is preserved in alcohol, the four others are fixed on three slides. The fixative is unknown; it is assumed that euparal had been used. Two of the five paratypes can be identified as belonging to other species: a) The individual preserved in alcohol was identified by Pettibone as <i>S. varians</i>, which is confirmed here; b) The red coloured worm on the slide labelled 118/1717 can only be tentatively identified as <i>S.</i> cf. <i>latipalpa</i> because the quality of the individual does not allow its exact identification.</p> <p> <b>Distribution:</b> Northwestern Atlantic (Cape Cod, Massachusetts).</p>Published as part of <i>Faulwetter, Sarah, Vasileiadou, Aikaterini, Papageorgiou, Nafsika & Arvanitidis, Christos, 2008, Description of a new species of Streptosyllis (Polychaeta: Syllidae) from the Mediterranean and Canary Islands with a re-description of Streptosyllis arenae and comments on the taxonomy of Streptosyllis and some morphologically similar genera, pp. 1-18 in Zootaxa 1847</i> on pages 3-
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
Impact of aquaculture to the benthic macrofauna and the ecosystem functions
No full textThe habitat inhabited by and in turn modified by the benthos is the result of many interacting factors, of regimes which cover scales from the global to the local, and of the intimate linkages between the water column and its factors and the substratum and its factors. Human impacts have major effects in the coastal benthic systems. In the case of Mediterranean fish farms it seems that they often are settled in the important habitat of Posidonia oceanica fields because the environmental characteristics of these areas (strong currents, good water quality, coarse sediment) fit perfectly with the special requirements of the fish farms. To study the impact of fish farming in different benthic Mediterranean habitats it was examined the pattern of organically enriched sediments by fish farming activities in a gradient of different sediment types. As testing grounds, muddy and seagrass habitats were chosen because of the different biogeochemical characteristics and functions of these areas. Our results showed the relationship of the biogeochemical variables with bathymetry and sediment composition. Although the spatial extent of the organic enrichment due to fish farming was the same, faunal organisms and geochemical variables showed different patterns according to the functions of their habitat. The sediment fluxes of nutrients and oxygen were used as proxies for the study of the relationship between macrobenthic diversity and ecosystem function in the gradients of organically enriched sediments. The relationship between benthic diversity and TOC concentration followed the pattern proposed by (Hyland et al. 2005). Our results showed that fauna, abiotic factors, oxygen fluxes and nutrient exchange determined the function of the benthic ecosystem. The shifts in biogeochemical processes occurred as a function of diversity and depended on the nature of the sediments. In order to remove the effect of sediment functioning variability, we repeated the analyses separately for the two major habitat types (bare sediment of muddy and seagrass habitats). It seems that the overall response of biological and geochemical variables to the organic enrichment varied considerably among habitat types and the effects on the benthic environment are more difficult to detect in coarse sediments through standard monitoring.Τα θαλάσσια ιζήματα κατοικούνται και μεταβάλλονται από τους βενθικούς οργανισμούς δημιουργώντας μια σειρά παραμέτρων που αλληλεπιδρούν, ενώ τα συστήματά που δημιουργούν μπορεί να καλύπτουν από τοπικής μέχρι παγκόσμιας κλίμακας διεργασίες. Οι ανθρωπογενείς επιδράσεις επηρεάζουν τα παράκτια βενθικά συστήματα. Ιδιαίτερα στην περίπτωση των ιχθυοκαλλιεργειών φαίνεται ότι συχνά εγκαθίστανται πάνω από τα σημαντικά ενδιαιτήματα των λειμώνων Posidonia oceanica επειδή τα ιδιαίτερα περιβαλλοντικά χαρακτηριστικά των περιοχών αυτών (ισχυρά ρεύματα, καλή ποιότητα νερού και αδρά ιζήματα) ταιριάζουν απόλυτα με τις απαιτήσεις των ιχθυοτροφείων. Για την μελέτη της επίδρασης των ιχθυοκαλλιεργειών σε διαφορετικά ενδιαιτήματα και ιζήματα της Μεσογείου ερευνήθηκαν οι διαφορές στο πρότυπο μεταβολής διαφορετικών τύπων ιζήματος σε ιζήματα οργανικά εμπλουτισμένα από ιχθυοκαλλιεργητικές δραστηριότητες. Ως περιοχές ελέγχου επιλέχθηκαν ιζήματα από λασπώδη και αμμώδη ενδιαιτήματα (σε γειτνίαση με λειμώνες φανερόγαμων), λόγω των διαφοροποιημένων βιογεωχημικών χαρακτηριστικών και λειτουργιών που παρουσιάζουν. Τα αποτελέσματα της παρούσας εργασίας έδειξαν την σχέση των βιογεωχημικών μεταβλητών με την βαθυμετρία και την σύσταση του ιζήματος. Ως εκφραστές της σχέσης της μακροβενθικής ποικιλότητας και της οικοσυστημικής λειτουργίας χρησιμοποιήθηκαν οι ροές των θρεπτικών και του οξυγόνου στην διαχωριστική επιφάνεια νερού ιζήματος. Η σχέση μεταξύ της ποικιλότητας των οργανισμών και της συγκέντρωσης του ολικού οργανικού άνθρακα ακολούθησε το πρότυπο που πρότειναν οι Hyland et al. (2005). Από τα αποτελέσματα φάνηκε ότι η πανίδα, οι αβιοτικοί παράγοντες και η ανταλλαγή του οξυγόνου και των θρεπτικών καθόρισαν την λειτουργία του βενθικού οικοσυστήματος. Οι μεταβολές στις βιογεωχημικές διεργασίες εμφανίστηκαν ως συνάρτηση της ποικιλότητας αλλά φάνηκε ότι εξαρτώνται και από την φύση των ιζημάτων. Παρά το ότι η χωρική έκταση του οργανικού εμπλουτισμού ήταν η ίδια οι βενθικοί οργανισμοί και οι γεωχημικές μεταβλητές των εξεταζόμενων ενδιαιτημάτων έδειξαν διαφορετικά πρότυπα ανάλογα με τις λειτουργίες τους. Για την αφαίρεση της επίδρασης λειτουργικής ποικιλότητας των ιζημάτων οι αναλύσεις επαναλήφθηκαν χωριστά για τους δύο κύριους τύπους ενδιαιτημάτων του γυμνού ιζήματος (λασπώδες και λειμώνων φανερόγαμων). Φαίνεται ότι η γενική απόκριση των βιολογικών και γεωχημικών παραμέτρων στον οργανικό εμπλουτισμό διαφοροποιήθηκε σημαντικά ανάμεσα στα διαφορετικά ενδιαιτήματα. Επίσης οι επιδράσεις στο βενθικό περιβάλλον των αδρών ιζημάτων είναι πιο δύσκολα ανιχνεύσιμες με τις συνήθεις μεθόδους παρακολούθησης
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