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Hemilucilia segmentaria (Fabricius, 1805) is a Neotropical blowfly species of forensic importance, with necrophagous and asynanthropic habits. In this study, the antennal ultrastructure of H. segmentaria was examined using scanning electron microscopy. The three antennal segments are covered by microtrichia. Sensilla chaetica were detected only on the scape and pedicel. Setiferous plaques and a pedicellar button were observed on the pedicel. Four types of sensilla were found on the postpedicel, including s. trichoidea, s. basiconica (subtype I, II and III), s. coeloconica subtype I, and sensory pits with s. coeloconica subtype II. This is the first time that the fine structure of the antennae of H. segmentaria was studied. Our results constitute a solid base for research on comparative and functional morphology in H. segmentaria and other blowflies.(AU)

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RATIONALE: Two Early Classic period (ca 250-600 CE) Maya carved, greenstone jade pendants, Specimens A and B, were recovered from the Pacbitun site in Belize in 1987. Mass scans of resolution ~600,000 were obtained for the jade pendants and two British Columbia jade ornaments. METHODS: Polyatomic ions from jade grit have been observed using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), specifically the Bruker Daltonics, SolariX XR, combined with matrix-assisted laser desorption/ionization (MALDI); the matrix material was α-cyano-4-hydroxycinnamicacid. RESULTS: Presented here is an interpretation of the mass spectrometric observations from multiplicities of silicate materials. Observation of novel polyatomic ion species of m/z 800-1400 indicate the ejection of charged ensembles composed of 60-180 atoms from jade grit. The charged ensembles represent minute regions of jade grit that have retained many of the spatial relationships of atoms within the jade; the required ejection energy is provided by laser photons accumulated in the matrix. Acid solutions of grit from Specimens A and ornament KMM were analyzed by inductively-coupled plasma mass spectrometry. The novelty of this application of mass spectrometry to jade was reported in the Journal of Archaeological Science: Reports. CONCLUSIONS: Isotopic fine structure analysis can yield elemental compositions for ions composed of base isotopes together with stable isotope intensities arising from ions with one and two additional neutrons. The analysis is challenging as jade is a multiplicity of similar solid solutions; thus, a multiple isotopic fine structure approach has been explored. Attempts to compose ensembles of atoms, of those elements found normally in coloured silicates, to match the observed ion mass/charge ratios were unsuccessful without the addition of multiple hydrogen atoms. The production of polyatomic ions of siliceous material may permit impinging fine glass coatings onto construction materials for protection against fire and weather.

RESUMO

In this study, the morphology, histology and fine structure of the stinger, a part of the venom apparatus of Euscorpius mingrelicus (Kessler, 1874) (Scorpiones: Euscorpiidae) were studied by light microscopy and transmission electron microscopy (TEM). The stinger, located at the end section of the telson, is sickle-shaped. The venom is ejected through a pair of venom pores on its subterminal portion. Both venom ducts extend along the stinger without contact with each other since they are separated by connective tissue cells. The stinger cuticle is composed of two layers. Additionally, there are many pore canals and some hemolymph vessels in the cuticle. This work constitutes the first histological and fine structure study on Euscorpius mingrelicus stinger.(AU)

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In this study, the morphology, histology and fine structure of the stinger, a part of the venom apparatus of Euscorpius mingrelicus (Kessler, 1874) (Scorpiones: Euscorpiidae) were studied by light microscopy and transmission electron microscopy (TEM). The stinger, located at the end section of the telson, is sickle-shaped. The venom is ejected through a pair of venom pores on its subterminal portion. Both venom ducts extend along the stinger without contact with each other since they are separated by connective tissue cells. The stinger cuticle is composed of two layers. Additionally, there are many pore canals and some hemolymph vessels in the cuticle. This work constitutes the first histological and fine structure study on Euscorpius mingrelicus stinger.(AU)

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The surface epithelium of the vas deferens of Agouti paca, a wild and large South American rodent, was basically formed by principal and basal cells being only the principal cells related to endocytosis processes and also secretion taking base on their cytoplasmic ultrastructural features. Principal cell of vas deferens epithelium were characterized mainly by presence of vesicles with several shapes, sizes and internalized content at their apical cytoplasm occurring smaller pits and pale small vesicles seen next to the apical brush border of microvillus. Moreover, coated vesicles, smooth surface vesicles and great vesicles; multivesicular bodies, endosomes and lysosomes were seen. Presence of an apocrine secretory apparatus was also viewed, showing apical cytoplasmic expansions protruding into the vas deferens luminal compartment. The basal flattened cells, without luminal surface contact, occurred next to the basement membrane of the ductus, and did no exhibit special ultrastructural features.

El epitelio que recubre la luz del conducto deferente de la laca (Agouti paca), un roedor silvestre de Sudamérica, está formado por células principales (P) y básales (B), en donde las células principales están asociadas a los procesos de endocitosis y secreción, teniendo una base en su característica ultraestructural citoplasmática. Las células principales de los vasos deferentes del epitelio se caracteriza principalmente por la presencia de vesículas con variadas formas, tamaños y contenido interior en su citoplasma apical produciendo pequeñas invaginaciones y pequeñas vesículas pálidas ubicadas continuas al borde en cepillo de las microveilosidades apicales. Además, fueron observados, vesículas de superficie lisa y vesículas de gran tamaño; órganos multivesiculares, endosomas y lisosomas. También se observó la presencia de un aparato secretor apocrino, con expansiones citoplasmáticas apicales que se protruyen en el compartimiento luminar del conducto deferente. Células básales aplanadas, sin contacto con la superficie luminal, se encuentran junto a la membrana basal del conducto, las que no presentan características ultraestructurales especiales.

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As células principais (P) do epitélio de revestimento do epidídimo de paca foram relacionadas com processos citofisiológicos de endocitoses do tipo adsortiva e de fase fluida, respectivamente, aparentemente realizando também secreção apócrina. Essas funções foram propostas embasando-se em características de ultra-estrutura das células P, em cujos citoplasma observaram-se um expressivo número de vesículas, com diferentes formas, tamanhos e presença de conteúdo internalizado em algumas das vesículas revestidas por endomembranas, ocorrendo ainda caveolas e vesículas diminutas localizadas junto à borda apical de microvilos. Ademais, observaram-se vesículas grandes e revestidas e/ou com superfícies lisas; endossomos, e lisossomos de localização predominantemente apical. Uma via de secreção apócrina foi sugerida com base na ocorrência de expansões (protrusões), citoplasmáticas intraluminais nas células P.(AU)

The principal (P) cells of epididymidis surface epithelium of Agouti paca were related to processes of adsorptive endocytosis and phase-fluid endocytosis, as well as protein secretion apparently also occur.These findings had been proposed on the base the cytoplasmic ultrastructural features of P cells in which were seen an expressive number of vesicles with several shapes, sizes and internalized content occurring also smaller pits and pale small vesicles located next to the apical brush border of microvilli. Moreover, occurred coated vesicles, smooth surface vesicles and great vesicles; multivesicular bodies, endosomes and lysosomes mainly viewed on supranuclear and apical positions. Presence of an appocrine secretory pathway was characterized in P cells through the occurrence of apical cytoplasmic expansions, protruding into the ducts epididymidis luminal compartment.(AU)

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The ultrastructure of zoospores of Asterococcus superbus (Cienk.) Scherffel was studied to provide ultrastructural data relevant to the systematic position of the genus. Our results demonstrated that the motile cells of A. superbus were similar to those of the tetrasporalean algae, such as Tetraspora sp. and Tetrasporidium javanicum Moebius. The flagellar apparatus of A. superbus had the same clock-wise orientation of basal bodies and the V-shaped alignment of basal bodies as Tetraspora cylindrica (Wahlb.) Ag. and T. lubrica (Roth) Ag., but differed by having rhizoplasts. The motile cells of A. superbus displayed chlamydomonadal ultrastructure, similar to Chlamydomonas reinhardtii Dangeard, including the absolute configuration of the flagellar apparatus. The pyrenoid matrix in A. superbus, however, showed a large lateral invagination occupied by chloroplast stroma, a characteristic that has never been observed in Chlorophyta.