Navegando por Palavras-chave "SEM"

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    Glass fission track analysis by AFM and SEM: Inferring latent track structure through etched tracks
    (Elsevier B.V., 2009-10-01) Hadler, J. C.; Alencar, I.; Iunes, P. J.; Guedes, S. [UNIFESP]; Universidade Estadual de Campinas (UNICAMP); Universidade Federal de São Paulo (UNIFESP)
    The main goal of this work is the study of latent fission track structure (or the associated defects density) analyzing the geometry evolution of etched tracks. in this way, measurements of diameter and cone angle for (235)U fission tracks reaching soda-lime glass surface with normal incidence were made. These glasses were etched since very short etching time up to times around standard etching used for optical microscopy. the measurements were obtained using an Atomic Force Microscope (AFM) and a Scanning Electron Microscope (SEM). Employing a geometrical model to describe track evolution in isotropic materials it was possible to conclude that the defect density in latent tracks can be considered constant along the fission fragment trajectory. (C) 2009 Elsevier B.V. All rights reserved.
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    A new species of Argulus (Crustacea, Branchiura, Argulidae) from the skin of catfish, with new records of branchiurans from wild fish in the Brazilian Pantanal wetland
    (Magnolia Press, 2017) Aguiar, Julio C.; Rosim, Daniele F.; Santos, Sonia M. C.; Luque, Jose L.; Ceccarelli, Paulo S.; Adriano, Edson A.; Tavares, Luiz E. R.
    During a survey conducted in the Cuiaba and Paraguay Rivers in the Brazilian Pantanal wetland, in the states of Mato Grosso and Mato Grosso do Sul, we found branchiurans associated with Pseudoplatystoma reticulatum, Pseudoplatystoma corruscans, Salminus brasiliensis and Zungaro zungaro. These branchiurans correspond to Argulus chiropteroideus sp. n., Argulus multicolor, Argulus nattereri, Argulus pestifer, Dolops carvalhoi and Dolops longicauda. Besides the description of the new species, in this study we also provide important morphological notes for diagnosis of the other species. Specimens of Argulus chiropteroideus sp. n. were collected from skin of P. reticulatum and P. corruscans. They differ from A. multicolor and Argulus chicomendesi, in the shape of the postantennal spines, which is medially convex and has two lateral and one anterior stout tips in the new species, and for having three claviform, digitate spines on the base of the second maxillae (absent in A. multicolor
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    Putative adhesive setae on the walking legs of the Paleotropical harvestman Metibalonius sp (Arachnida: Opiliones: Podoctidae)
    (Amer Arachnological Soc, 2018) Gainett, Guilherme; Sharma, Prashant P.; Giribet, Gonzalo; Willemart, Rodrigo Hirata [UNIFESP]
    We provide a first scanning electron microscopy examination of the Paleotropical harvestman family Podoctidae (Opiliones: Laniatores), focusing on the distitarsus of the legs of Metibalonius sp. Distitarsi I and II are mostly equipped with olfactory sensilla chaetica with wall pores, while those of legs III and IV have gustatory sensilla chaetica with a tip pore, ventral trichomes with ovate tips (non-sensory) and a type of spatulate seta. Spatulate setae are present in adults of both sexes, with no apparent sexual dimorphism, but they are absent in the nymph. Seven of these setae are inserted on the frontal surface of the last tarsomere of legs III and IV, with the tips oriented ventrally. Each seta has an s-shaped socketed shaft, which terminates distally in a spatula-shaped structure. The distribution of spatulate setae, restricted to legs III and IV (walking legs), the position on the distitarsi, and the typical spatulate shape suggest an adhesive function for these structures. Morphology and position suggest that the socketed spatulate setae of Metibalonius sp. and the previously reported scopular spatulate setae of other harvestmen constitute two distinct types of adhesive structures, highlighting the diversity of adhesive structures in Laniatores. Future investigations about the natural history of this species and internal morphology of spatulate setae are necessary to test further functional hypotheses and to determine their behavioral role.
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    Scanning electron microscopic study of the dorsal surface of the tongue of Calomys callosus mouse
    (Gustav Fischer Verlag Jena, 1995-11-01) Utiyama, Cássia; Watanabe, Ii-sei; Konig, Bruno; Koga, Luciane Y.; Semprini, Marisa; Tedesco, Roberto Carlos [UNIFESP]; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)
    The characteristics of the dorsal mucosal surface of Calomys callosus' tongue were studied employing scanning electron microscopy. The samples were fixed with modified Karnovsky solution, and postfixed in 1% OsO4, followed by dehydration and critical point drying. The scanning electron microscopy gives a three dimensional image of the filiform, fungiform, vallate and foliate papillae. The filiform papillae were found on the anterior tip and dorsal surface; the fungiform papillae on the dorsal and anterior surfaces; only one vallate papilla, elongated in shape, is located in the posterior third, and the small foliate papillae were to be seen in the posterolateral region of the tongue.