11 resultados para bronze sculpture
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
Plicatulostrea onca, a new genus and species of Plicatulidae, is described based on shell and anatomy. The samples were collected under intertidal rocks at Kungkrabaen Bay, Thailand. Plicatulostrea differs from other plicatulids mainly in lacking undulations or shell sculpture, by long projections of the hinge teeth of the right valve and extreme body compression. Plicatulostrea onca has a radially arranged spots at the shell surface and typical plicatulid anatomy, differing mainly by the richness of papillae on the mantle edge and by invasion of the gonad along the mantle lobes. Some comments on the anatomy of the family are also provided.
Resumo:
A revision of the deep-water verticordiid genus Spinosipella is provided, based on conchological and anatomical characters. The genus is considered distinct from Verticordia (of which it was considered a subgenus) based on the strong ribs, prickly surface, reduction of lunula, relative large size, weakly spiral valve shape, and other characters. The following species are considered in the genus: (1) Spinosipella agnes new species, ranging from Florida, USA, to Rio de Janeiro, Brazil, and also including the Porcupine Abyssal Plain in the North Atlantic; (2) S. tinga new species, occurring from Rio de Janeiro to Rio Grande do Sul, Brazil; (3) S. acuticostata (Philippi, 1844), a Pliocene fossil from southern Italy; (4) S. deshayesiana (Fischer, 1862), from south and central Indo-Pacific (S. ericia Hedley, 1911, the type species of the genus, was revealed to be a new synonym of S. deshayesiana); and (5) S. costeminens (Poutiers, 1981), from the tropical west Pacific. The five species differ mainly in conchological details of the number and size of ribs, of the prickly sculpture, shape of the shell, of the hinge and the degree of convexity. Anatomical description is also provided for the two Pacific species, which differ among themselves mainly by the size of the pair of renal folds. From the standpoint of anatomical characters, the more significant are: the wide lithodesma; the elongation of the auricles, crossing the roof of pallial cavity; a tall digital fold in posterior region of supraseptal chamber; the low but wide palps; the muscular, gizzard-like stomach; the complete separation of both constituents of the hermaphroditic gonad (a ventro-posterior testicle and a centro-dorsal ovary), and a complete fusion of the visceral ganglia.
Resumo:
A correlation between lattice parameters, oxygen composition, and the thermoelectric and Hall coefficients is presented for single-crystal Li0.9Mo6O17, a quasi-one-dimensional (Q1D) metallic compound. The possibility that this compound is a compensated metal is discussed in light of a substantial variability observed in the literature for these transport coefficients.
Resumo:
Two new species of shallow water Tornidae are found in Espirito Santo state, Brazil, formally described herein. They belong to a complex group of tiny gastropods, in such the taxonomy is very confused. Cyclostremiscus mohicanus sp. n. is characterized by three well-developed spiral, equidistant carinas, working as base of three series of tall, aligned periostracal rods. Episcinia itanhuna sp. n. has as single sculpture a series of pustules in periphery, but the periostracum bears three series of peripheral fringes with irregular rods. The new species are compared with the allies, showing a close relation with Caribbean fauna, but possessing worthy differences. These similarities have raised misidentifications.
Resumo:
Gold plated surfaces are widely applied in several technical and decorative fields. The two main issues regarding the discussion on the field of precious metal coatings concern the increase in the use of thinner gold layers and 'Ni free' substrates. In order to ensure the quality of the final products, the effects of the plated surfaces on their performance require thorough and accurate research. In this paper, the corrosion resistance of gold plated nickel, copper and bronze was investigated by electrochemical methods specifically potentiodynamic polarisation and electrochemical impedance spectroscopy in phosphate buffered saline. The cytotoxicity of the gold plated substrates was also evaluated and compared. The results showed that the substrate related to the best corrosion resistance and cytotoxicity among the tested ones was bronze, and the one with the lowest performance was nickel.
Resumo:
The deep-water molluscs collected during the expedition MD55 off SE Brazil have been gradually studied in some previous papers. The present one is focused on samples belonging to caenogastropod taxa Xenophoridae Troschel, 1852, Cypraeoidea Rafinesque, 1815, mitriforms and Terebridae Morch, 1852. Regarding the Xenophoridae, Onustus aquitanus n. sp. is a new species, collected off the littoral of Espirito Santo and Rio de Janeiro, Brazil, 430-637 m depth (continental slope). The main characters of the species include the small size (c. 20 mm), the proportionally wide shell, the white colour, the short peripheral flange, the oblique riblets weakly developed and a brown multispiral protoconch. This appears to be the smallest living species of the family, resembling in this aspect fossil species. In respect to the Cypraeoidea, the following results were obtained: family Cypraeidae Rafinesque, 1815: Erosaria acicularis (Gmelin, 1791) and Luria cinerea (Gmelin, 1791) had the deepest record, respectively 607-620 m and 295-940 m, although the samples were all dead, eroded shells. Family Lamellariidae d'Orbigny, 1841: a total of three lots were collected, provisionally identified as Lamellaria spp. as the samples consist of only vestigial shells; possibly each lot represents a different species. Family Pediculariidae Gray, 1853: a sample of Pedicularia tibia Simone, 2005 was found, expanding the range c. 1000 km southwards, from Ceara to Espirito Santo. Family Ovulidae Fleming, 1822: Pseudosimnia lacrima n. sp., collected off Espirito Santo, 607-620 m depth, is described here and is mainly characterised by its strong biconic outline, small size (c. 7 mm), and a thick peripheral callus. Family Triviidae Troschel, 1863: Cleotrivia antillarum (Schilder, 1922) is recorded for the first time as deep as 620 m, and its distribution expanded from Rio Grande do Norte to Espirito Santo; Dolichupis akangus n. sp. with rounded outline and c. 15 transverse ribs; D. pingius n. sp. with the outer lip expanded posteriorly and c. 10 ribs. In respect to the mitriform neogastropods, the following species are emphasised: family Costellariidae MacDonald, 1860: Vexillum sp., 607-620 m depth; Turricostellaria amphissa n. sp., 295 m depth; T. jukyry n. sp.; T. apyrahi n. sp., both 790-1575 m depth; T. ovir n. sp., 1200 m depth; Nodicostellaria crassa (Simone, 1995), 240-600 m depth, with extension northwards of the range up to Espirito Santo; Austromitra decresca n. sp., 60-105 m depth. Family Mitridae Swainson, 1829: Subcancilla joapyra n. sp., 295 m depth; S. cf. straminea (Adams, 1853), 607-620 m depth. Family Volutomitridae Gray, 1854: Microvoluta corona n. sp., 1500-1575 m depth. Family Mitromorphidae Casey, 1904: Mitromorpha sama n. sp., 607-940 m depth; M. mirim n. sp., 60105 m depth. Regarding the conoidean Terebridae, this paper is a complement of a previous study. It deals with a new species Terebra assu Simone n. sp., from the Abrolhos Bank, 295 m depth, characterised by its narrow outline, yellowish colour, weak sculpture on the last whorls, and a proportionally broad, paucispiral protoconch. A second finding of Terebra alagoensis Lima, Tenorio & Barros, 2007 expands the geographic range from Alagoas to north Espirito Santo. A discussion on the systematics of the "complex Terebra doellojuradoi" in South American coast is also provided, highlighting the improbability of synonymy between T. leptapsis Simone, 1999 and T doellojuradoi Carcelles, 1953. Differences in size, sculpture, spire angulation, aperture, and mainly in protoconch, indicate specific separations. The presently studied terebrids belong to the "complex Terebra doellojuradoi", which encompasses closely related, deep-water, small species, possessing a relatively high degree of endemicity.
Resumo:
Occurrence of Zoophthora radicans infecting nymphs and adults of Thaumastocoris peregrinus Carpintero and Dellape, 2006 is reported in Brazil. This is a new record of host for this fungal species and the first fungal pathogen associated with this pest worldwide. Infection of Z. radicans on T. peregrinus populations on commercial Eucalyptus plantation (Eucalyptus spp.) reached up to 100%, and low insect densities were associated with high levels of fungal infection in three out of seven plots. This pathogen seems to be virulent against T. peregrinus and may play an important role in population regulations of this invasive pest through naturally induced epizootics. (c) 2012 Elsevier Inc. All rights reserved.
Resumo:
The patination of copper is known for its complexity and heterogeneous formation. For a deeper investigation, a locally resolved surface analysis was considered. An exact determination of the accessed area and a potentiostatic control in a three-electrode configuration was reached with the use of the electrochemical microcell technique, which enables local electrochemical measurement such as local electrochemical impedance spectroscopy and cyclic voltammetry. Such a technique provides a unique way for performing the investigation of heterogeneities on electrode surfaces. The local electrochemical measurements on the artificially patinated surface have allowed distinguishing areas of different reactivity even when the analysis of the surface revealed a homogenous chemical composition of patina. Local measurements with the electrochemical microcell showed the presence of small defects on the patina layer that can be modelled by considering a hemispherical diffusion process at small active areas surrounded by larger less reactive domains.
Resumo:
A sample of Pulmonata collected in Santa Maria da Vitória, interior of Bahia, Brazil, in Caatinga semi-arid environment, is studied taxonomically. From the five species, four are revealed as new, including a new genus. The new taxa are the Bulimulidae (1) Kora corallina gen. et sp. n. characterized by the elongated shell with aperture somewhat dislocated from the shell axis, and an oblique tooth in middle level of inner lip; (2) Spixia coltrorum, mainly characterized by an uneven spire, delicate sculpture and peristome with 4 equidistant teeth; (3) Anostoma tessa, mainly characterized by a broad spire and well-developed anal canal; and the Megalobulimidae (4) Megalobulimus amandus, mainly characterized by pointed protoconch sculptured by dense quantity of axial cords. Rhinus suturalis is the only previously known species, but its geographic distribution is expanded southwards to Bahia state. A discussion with respect to necessity for improving the study on the malacofauna from the interior region of the Brazilian Northeast and the importance for preservation of the Caatinga biome is also provided.
Resumo:
INTRODUÇÃO: A trombose de veia porta foi considerada contraindicação ao transplante de fígado no passado em razão da elevada morbi-mortalidade. Diversos avanços permitiram melhora dos resultados. OBJETIVO: Revisão dos avanços e das estratégias cirúrgicas utilizadas para realização do transplante de fígado na vigência de trombose de veia porta. MÉTODO: Revisão da literatura nas bases de dados Medline, Scielo, Lilacs cruzando os descritores: portal vein thrombosis, liver transplantation, vascular complications, jump graft, graft failure, multivisceral transplant. Foram estudados a epidemiologia, fatores de risco, classificação, diagnóstico, estratégias cirúrgicas e resultados. CONCLUSÃO: A trombose de veia porta deixou de ser contraindicação para o transplante hepático. O cirurgião dispõe atualmente de uma série de estratégias para realização do transplante, variando conforme o grau da trombose. Apesar de implicar em maior morbidade e taxas de re-trombose, os resultados do transplante na presença de trombose portal são semelhantes aos observados nas séries habituais.
Resumo:
Rationale: The excessive intake of vitamin A in the form of vitamin concentrate, supplement or vitamin-rich liver can result in hypervitaminosis A in man and animals. Although osteopathologies resulting from chronic vitamin A intoxication in cats are well characterized, no information is available concerning feline hypervitaminosis A-induced liver disease. Clinical summary: We report the first case of hepatic stellate cell lipidosis and hepatic fibrosis in a domestic cat that had been fed a diet based on raw beef liver. Radiographic examination revealed exostoses and ankylosis between vertebrae C1 and T7, compatible with deforming cervical spondylosis. Necropsy showed a slightly enlarged and light yellow to bronze liver. Microscopic and ultrastructural analyses of liver tissues revealed diffuse and severe liver fibrosis associated with hepatic stellate cell hyperplasia and hypertrophy. These cells showed immunopositive staining for α-smooth muscle actin and desmin markers. The necropsy findings of chronic liver disease coupled with osteopathology supported the diagnosis of hypervitaminosis A. Practical relevance: As in human hepatology, if there is dietary evidence to support increased intake of vitamin A, then hypervitaminosis A should be considered in the differential diagnosis of chronic liver disease in cats.