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FIGURE 3 in The Cylindrobulla / Ascobulla complex—unraveling problems in identification and adding to Cylindrobulla diversity (Gastropoda, Heterobranchia, Sacoglossa) by describing a new species
No full textFIGURE 3. Cylindrobulla schuppi sp. nov. schematic drawing of digestive system. Stomach lies within digestive gland. Abbreviations: an—anus, dgl—digestive gland, ep esophageal pouch, es—esophagus, lgl—lip gland, m—mouth area, ogl—oral gland, ph—pharyngeal bulb, s—stomach, sgl—salivary gland.Published as part of Laetz, Elise, Christa, Gregor, Händeler, Katharina & Wägele, Heike, 2014, The Cylindrobulla / Ascobulla complex—unraveling problems in identification and adding to Cylindrobulla diversity (Gastropoda, Heterobranchia, Sacoglossa) by describing a new species, pp. 339-362 in Zootaxa 3893 (3) on page 346, DOI: 10.11646/zootaxa.3893.3.2, http://zenodo.org/record/22778
Switching off photosynthesis: The dark side of sacoglossan slugs
No full textSometimes the elementary experiment can lead to the most surprising result. This was recently the case when we had to learn that so-called "photosynthetic slugs" survive just fine in the dark and with chemically inhibited photosynthesis. Sacoglossan sea slugs feed on large siphonaceous, often single-celled algae by ingesting their cytosolic content including the organelles. A few species of the sacoglossan clade fascinate researcher from many disciplines, as they can survive starvation periods of many months through the plastids they sequestered, but not immediately digested - a process known as kleptoplasty. Ever since the term "leaves that crawl" was coined in the 1970s, the course was set in regard to how the subject was studied, but the topics of how slugs survive starvation and what for instance mediates kleptoplast longevity have often been conflated. It was generally assumed that slugs become photoautotrophic upon plastid sequestration, but most recent results challenge that view and the predominant role of the kleptoplasts in sacoglossan sea slugs
Kleptoplasty: Solar-powered sea slugs house stolen plastids in kleptosomes
No full text501100001659 Deutsche Forschungsgemeinschaft501100004189 Max-Planck-Gesellschaf
Plastid survival in the cytosol of animal cells
No full textSome marine slugs sequester plastids from their algae food, which can remain photosynthetically functional in the animal's digestive gland cells in the absence of algal nuclei. The sequestered plastids (kleptoplasts) appear to maintain functional photosystems through a greater autonomy than land plant plastids. If so, kleptoplast robustness is a plastid-intrinsic property, and it depends on the animal to manage an alien organelle on the loose in order to maintain it long term
FIGURE 10. A in The Cylindrobulla / Ascobulla complex—unraveling problems in identification and adding to Cylindrobulla diversity (Gastropoda, Heterobranchia, Sacoglossa) by describing a new species
No full textFIGURE 10. A comparison of radular teeth from Cylindrobulla species. A—C. beauii as drawn by Marcus (1972); B—C. beauii as observed in this analysis; C—C. gigas based on SEM micrographs made by Mikkelsen (1998); D—C. phuketi based on SEM micrographs made by Jensen (1989); E—C. xishaensis as drawn by Guangyu (1978); F—C. schuppi sp. nov. as observed in this analysis.Published as part of Laetz, Elise, Christa, Gregor, Händeler, Katharina & Wägele, Heike, 2014, The Cylindrobulla / Ascobulla complex—unraveling problems in identification and adding to Cylindrobulla diversity (Gastropoda, Heterobranchia, Sacoglossa) by describing a new species, pp. 339-362 in Zootaxa 3893 (3) on page 355, DOI: 10.11646/zootaxa.3893.3.2, http://zenodo.org/record/22778
Cylindrobulla Fischer 1857
No full textGenus Cylindrobulla Fischer, 1857 Type species: Cylindrobulla beauii Fischer, 1857. Diagnosis. Small slugs with thinly calcified, external shells and bi-lobed cephalic shields. Rasping radular teeth with a broad base and several denticles; usually square shaped, but never elongate as in all other sacoglossan species. In contrast to former descriptions and definitions, all recent investigations of Cylindrobulla species indicate the presence of an ascus, but this lies hidden within the pharyngeal musculature (Marcus 1972; Jensen 1989; new and unpublished data of HW).Published as part of Laetz, Elise, Christa, Gregor, Händeler, Katharina & Wägele, Heike, 2014, The Cylindrobulla / Ascobulla complex — unraveling problems in identification and adding to Cylindrobulla diversity (Gastropoda, Heterobranchia, Sacoglossa) by describing a new species, pp. 339-362 in Zootaxa 3893 (3) on page 342, DOI: 10.11646/zootaxa.3893.3.2, http://zenodo.org/record/22778
Cylindrobulla beauii Fischer 1857
No full textCylindrobulla beauii Fischer, 1857 Material. Shell length of investigated specimen (Figure 1 C): 2.2 mm; shell width 1.2 mm. Distribution. This species is extensively recorded in Brazil, Caribbean and Florida (Mikkelsen 1998). Description. Only partial re-examination was possible since part of animals were used for barcoding and radula examination. Our results agree with description of Mikkelsen (1998) (see Figures 1 C, F, H). External anatomy of live specimen. Many internal structures visible through shell, similar to those of new species (Figure 1 D). Radula. Radula with 70 broad smooth teeth, each roughly pentagonal in shape (Figure 4 D, E). Each tooth with 3–4 slightly curved denticles on each side, increasing in size toward center and flanking a single median cusp. Median cusp and denticle immediately flanking on each side gradually protrude from other lateral cusps to form a trident shape (Fig. 4 F). Further anatomical structures. Digestive gland large and filling most parts of visceral cavity, including inner coils.Published as part of Laetz, Elise, Christa, Gregor, Händeler, Katharina & Wägele, Heike, 2014, The Cylindrobulla / Ascobulla complex — unraveling problems in identification and adding to Cylindrobulla diversity (Gastropoda, Heterobranchia, Sacoglossa) by describing a new species, pp. 339-362 in Zootaxa 3893 (3) on pages 348-349, DOI: 10.11646/zootaxa.3893.3.2, http://zenodo.org/record/22778
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
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