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Palaeoxylotomical Study Of A New Collection From Zarand Miocene Petrified Forest, South Apuseni Mts.
No full textIamandei, Stanila, Iamandei, Eugenia, Todea, Petru (2020): Palaeoxylotomical Study Of A New Collection From Zarand Miocene Petrified Forest, South Apuseni Mts. Acta Palaeontologica Romaniae 16 (1): 19-34, DOI: 10.35463/j.apr.2020.01.02, URL: http://dx.doi.org/10.35463/j.apr.2020.01.0
Thujoxylon undetermined
No full text<p> <i>Thujoxylon</i> sp.</p> <p>Fig. 1, a-i; Fig. 2, a-i.</p> <p> <b>Material</b></p> <p>Two samples of petrified wood collected from South Apuseni mts., Ociu area, Bisericii brook, from Mid-Miocene deposits (late Badenian-early Sarmatian), kept now in “ Todea Collection ”, in Crișcior- Brad locality, under the indicative OB-4 and OB-5, both with standard oriented thin sections prepared, were submitted to the paleoxylotomical study.</p> <p> <b>Microscopic description</b></p> <p>The growth rings are relatively wide, of 36-60 cells, with distinct boundaries, since the late wood is represented by 5-7 tangential rows of radially flattened and thick-walled cells, disperse few parenchyma cells often with black content. Normal resin canals are absent.</p> <p>The tracheids, in the early-wood, are big, quadrangular or polygonal shaped, or slightly elongate, and are relatively thin-walled (4-6 μm the double wall). Their lumina have slightly rounded corners, and radial / tangential diameters of 25-35 / 20-30 µm, gradually diminishing through transitional 6-8 tangential rows of smaller lumened cells to the latewood, where they appear in 8-12 tangential rows of small, quadrangular, radially crushed and very thick-walled cells, of 8-12 μm double wall, and with r / tg diameters of 10-15/8-15 µm. There are 1-9 radial rows between two rays and the density is of 1900-2025 tracheids on sq. mm. The tangential tracheidal walls seem to be pitted, with small and spaced pits. The radial abietineous pitting is uniseriate, spaced or nearly contiguous and probably with crassulae, difficult to see due to bad preservation. The bordered pits are relatively small (8-12 µm the diameter), with round aperture, of 3-5 µm in diameter.</p> <p>The axial parenchyma seems to be absent, or rare, or difficult to observe in cross-section, since is quite similar to the tracheids. However, it is obvious in tangential view, having horizontal nodular walls, and presenting glomeruli of resin inside, or plugs with round concavities.</p> <p>The rays are uniseriate, not too high, of up to 8-12 cells. Radially the rays seem to be homogeneous and are constituted from cells of 12-14 μm taller marginals and with waved outer walls. No details on the inclined walls have been observed. Indentures probably present, difficult to observe due to bad preservation. In the cross-fields, 1-2 small round to oval, small, badly preserved cupressoid or taxodioid pits of 5-6 μm in diameter, horizontally arranged or in vertical pairs in the late-wood cross-fields, having rounded lens-like, inclined to vertical apertures. In the marginal cross fields 2-4, as superposed pairs of round pits are present.</p> <p> <b>Affinities and discussions</b></p> <p> The palaeoxylotomical observations made on the studied specimens suggests, by the aspect of the structure in cross section, devoid of resin canals, with few parenchyma having horizontal nodular walls and cupressoid cross-fields with typical aspect of a cupressaceous structure of Thujidae group, especially of <i>Thuja</i> type, even if some badly preserved details do not allow identifying a species. The identification key of Vaudois & Privé (1971) explain that the cupressaceous structures have “zones d’acroissement distinctes, tracheides a ponctuations radiales abietineénnes uniseriées, parenchyme absent ou rare, a parois transversales noduleuses ou ponctuées, rayons généralement peu élevés, uniseriés, parfois biseriés sur un faible hauteur; champs de croisement contenant 1-4 ponctuations taxodioides, parfois cupressoides, indentures présentes” for <i>Thuja</i> type structure. The <i>Chamaecyparis</i> type has a lot of parenchyma and the <i>Juniperus</i> type has specific juniperoid nodules on the inclined tangential walls of ray cells in tangential view, details not observed in our specimens.</p> <p> The fossil morphogenus, initially variably spelled as <i>Thuyoxylum-Thuoxylon-Thuioxylon-Thuyoxylon</i>, was correctly spelled as <i>Thujoxylon</i> by Hartig in 1848 (see Andrews, 1955, p. 251; Dijkstra & van Ameron, 2002).</p> <p> Numerous morphospecies were described, in time (see also Vaudois & Prive, 1971 revising the Cupressaceous fossil lignotaxa). Between the last described species, we cite <i>Thujoxylon antissum</i> Süss & Velizelos, 1998, described from Lesvos, Greece, a tertiary form representing root-wood with a special pattern of growth rings and cross section. The species was quoted and discussed again by Mantzouka et al. (2013). Also, a Cretaceous species named <i>Thujoxylon beipiaoense</i> Ding et al., 2016, having similar features, was described from China.</p> <p> Pretty badly preserved specimens were described from Romanian extra-Carpathian area as <i>Cupressinoxylon</i> sp. aff. <i>Thujoxylon</i> sp. (Iamandei et al. 2008, 2011, 2012).</p> <p> Anyway, taking into account the papers of Greguss (1967), Dupéron-Laudouéneix (1979), Zalewska (1953), the revised diagnoses of Kräusel (1949) and Vogellehner (1967, 1968), and using the key of identification proposed by Vaudois et Privé (1971), we assign our studied specimens to <i>Thujoxylon</i> sp., and no more, due to bad preservation of the studied material.</p>Published as part of <i>Iamandei, Stanila, Iamandei, Eugenia & Todea, Petru, 2020, Palaeoxylotomical Study Of A New Collection From Zarand Miocene Petrified Forest, South Apuseni Mts., pp. 19-34 in Acta Palaeontologica Romaniae 16 (1)</i> on pages 19-22, DOI: 10.35463/j.apr.2020.01.02, <a href="http://zenodo.org/record/10520679">http://zenodo.org/record/10520679</a>
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
Spiroplatanoxylon densiradiatum Suss 2007
No full text<i>Spiroplatanoxylon densiradiatum</i> (Petrescu) Süss 2007 <p>Fig. 4, a-i; Fig. 5, a-i.</p> <p> <b>Material</b></p> <p>From two samples of petrified wood collected from South Apuseni mts., Ociu area, Bisericii Book, from Mid-Miocene deposits (Late Badenian-Early Sarmatian), kept within “ Todea Collection ”, in Crișcior- Brad locality, under the indicative OB-2 and OB-6, with standard oriented thin sections that were submitted to the paleoxylotomical study.</p> <p> <b>Microscopical description</b></p> <p>The growth rings are distinct, the wood structure is diffuse-porous to slightly semi-ring-porous and the rays are dilated at ring boundaries.</p> <p>The vessels appear, in cross-section, as solitary pores or as tangential to diagonal pairs, sometimes slightly angular, rounded or deformed and moderately thick-walled, 7- 10 μm the double wall. The woody bundles, between two rays, may have 1-5 vessels, which are mean sized, with the radial/tangential diameters ratio 30-63/15-35 μm The pores’ size is relatively uniform 275-360 per square mm, we can talk about a diffuse-porous wood tending to semi-ring-porous, since a gradually diminishing size is observed to the late-wood, where smaller sized pores are visible, of 15-30/12-15 μm the diameters ratio (r/tg). In longitudinal sections scalariform perforations can be seen, on tilted plates, with 12-18 or more thin bars, quite badly preserved. The vessels’ walls are bordered pitted, with opposite, horizontaly elongate pits to scalariform, by apertures’ coalescence. Even if badly preserved, helical thickenings are present, no tyloses inside the vessels appear, and the vessels’ elements length is of 80-200 μm, or difficult to measure.</p> <p>The axial parenchyma is of apotracheal type, diffuse, as scattered cells among the fibers or as uniseriate short lines and as marginal (terminal) parenchyma. In longitudinal view, the parenchyma cells are thin-walled, probably simple pitted, and have strands of rectangular chambered cells, empty or bearing prismatic crystals.</p> <p>The rays, in cross section seen, have linear trajectory, rectangular cells, are two-sized, of 1-4, respectively, (6)8- 12 cells wide, and have typical platanoid dilations at ring boundaries. In tangential view they appear fusiform and compact, sometimes have cell-sheath and are usually high. The body ray-cells are slightly polygonal, unequally sized and relatively thick-walled. The uniseriate ray endings have 1-5 slightly polygonal cells, often slightly larger. The ray-frequency is of 9-12 rays per tangential mm. Radially seen, the rays appear heterocellular, with procumbent body cells, the marginals square or slightly taller. Sometimes hypertrophied cells appear, most probably secretory and/or bearing crystals.</p> <p>The fibres, polygonal in cross section, have rounded lumina, and are quite thick-walled (up to 3-5 μm double wall). The longitudinal walls are pitted, but quite badly preserved.</p> <p> <b>Affinities and discussions</b></p> <p>All the observed microscopical features in the studied specimens showed in cross-section a diffuse-porous to semi-ring-porous vessels’ distribution, opposite bordered pits, horizontaly elongate to scalariform by apertures’ coalescence on vessels, spiral thickenings and scalariform perforations, and heterocellular rays dilated at ring boundary (typical “platanoid dilatations”), so, we appreciated that there are clear similarity with the platanaceous structure. The Platanaceae is a monogeneric family of flowering plants, from the order Proteales. Platanus is a large deciduous tree adapted to temperate climate and has 10-12 species and some hybrids, scattered in North America, Southeast Europe, Southern and Eastern Asia.</p> <p>Its secondary xylem has moderately small vessels in radial small groups, having scalariform and simple perforations, intervascular bordered pits elongate to scalariform parenchyma apotracheal, two-sized rays with typical platanoid dilation at the ring boundary (Greguss, 1959; Watson & Dallwitz, 1992)</p> <p> As it is known, there are three still valid fossil genera of platanaceous woods: <i>Plataninium</i>, <i>Platanoxylon</i> and <i>Spiroplatanoxylon</i>. Extended discussions concerning the validity of these genera and of their associated species are already published (Süss, 2007; Sakala et al., 2010; Gryc & Sakala, 2010; Továrková et al., 2011; Koutecky & Sakala, 2015; Iamandei et al., 2020, in this Journal).</p> <p> • The genus name <i>Plataninium</i> is still used by some American, Asiatic and even European scientists, and is considered as a primitive type which support the Bayley concept regarding the xylotomic features’ evolution (see Wheeler & Baas, 1991) since it has scalariform perforations, spiral thickenings, marked heterocellular rays. Many scientists have described species under this genus name (see Felix, 1894; Brett, 1972; Crawley, 1989; Poole et al., 2002; Meijer, 2000; Page, 1968; Stockmans, 1936; Wheeler, McClammer & LaPasha, 1995; Takahashi & Suzuki, 2003).</p> <p> • The genus <i>Platanoxylon</i> Andreánszky, 1951 was also subject of revision and dispute at least in the last time (Süss 1960, 1971, 1986, 2007; Süss & Müller-Stoll, 1977). This genus is considered by Selmeier (1996) as representing an evolved type which has simple (and scalariform) perforations, no spiral thickenings and homocellular rays, and was longtime admitted as the best equivalent of the extant platanoid taxa (Süss, 1960, 1971, 1980, 1986, 2007; Süss & Müller-Stoll, 1977).</p> <p> • The genus name <i>Spiroplatanoxylon</i> Süss, 2007 was created from the Tertiary of Europe and southwestern Asia and is characterized, beside the <i>Platanus</i> -like wood structure, by two aspects considered more primitive but characteristic to the genus: the scalariform perforation plates and the helical thickenings on vessels. From this reason a lot of species of <i>Plataninium</i> and <i>Platanoxylon</i> were attributed to <i>Spiroplatanoxylon</i> (see Süss, 2007; Gryc & Sakala, 2010). Also, <i>Icacinoxylon</i> was reconsidered as bad identification of a taxon with only intertropical extant correspondents and the numerous species described in Europe, but not only, were reassigned to <i>Spiroplatanoxylon</i> (Süss, 2007).</p> <p> In a recent paper on some wood remains from Bozovici, an extended discussion on the evolution of the taxonomy of the fossil platanaceous structures is done (Iamandei et al., 2020, in this Journal). All the described xylotomical features of the studied specimens are consistent with the genus diagnosis of <i>Spiroplatanoxylon</i>, and for this reason we will attribute our woods to it.</p> <p> Since the wood structure of here studied specimens from South Apuseni mts., from Ociu locality, on Church Brook, xylotomically resembles to many already described species, for example to the forms described, by Petrescu & Dragastan (1972) as <i>Spiroplatanoxylon grambastfessardi</i> (Petrescu) Iamandei (in Iamandei et al., 2020, in this Journal), from the Oligocene of Telega and, also, by Petrescu & Nuţu (1970, 1971, 1972) from Prăvăleni, respectively from Almaşul Mare and Boiu, as to <i>Spiroplatanoxylon porosum</i> (Felix) Süss, 2007 and also with the species <i>Spiroplatanoxylon densiradiatum</i> (Petrescu) Süss, 2007 (former <i>Icacinoxylon densiradiatum</i> Petrescu, 1978) which is almost identical, having smaller angular vessels, solitary or in clusters, scalariform perforation plates with 20-35 bars, spiral thickenings and ray cells with crystals, two-sized rays and high ray-frequency.</p> <p> We tried to find very specific details, to discriminate between the described species, and to identify the studied material, which is quite badly preserved, but showing distinct growth rings, diffuse-porous wood structure to slightly half-ring-porous, vessels solitary or in tangential to diagonal pairs, angular to rounded, thick-walled, mean-sized, scalariform perforations with 12-18 thin bars or more, bordered opposite pits, horizontally elongate to scalariform by apertures’ coalescence, helical thickenings, no tyloses; axial parenchyma apotracheal diffuse, and as marginal parenchyma, thin-walled cells in strands of rectangular chambered cells, bearing prismatic crystals; rays, two-sized (1-4 and (6)8-12 cells wide), with platanoid dilations, fusiform and compact usually high, sometimes cell-sheath, body ray-cells slightly polygonal, unequally sized, thick-walled, rays heterocellular, with procumbent body cells and marginals square or slightly taller, sometimes with hypertrophied cells probably secretory and/or bearing crystals, fibres polygonal, thick-walled, pitted. Since we appreciate a close similarity with <i>Spiroplatanoxylon densiradiatum</i> (Petrescu) Süss, 2007, we assign our two studied specimens to this species.</p>Published as part of <i>Iamandei, Stanila, Iamandei, Eugenia & Todea, Petru, 2020, Palaeoxylotomical Study Of A New Collection From Zarand Miocene Petrified Forest, South Apuseni Mts., pp. 19-34 in Acta Palaeontologica Romaniae 16 (1)</i> on pages 25-28, DOI: 10.35463/j.apr.2020.01.02, <a href="http://zenodo.org/record/10520679">http://zenodo.org/record/10520679</a>
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
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