945 resultados para Reactive species of oxygen
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Four new species of Anastrepha Schiner were collected in McPhail-type traps hung in trees in a natural reserve and in commercial papaya orchards in Linhares, Espirito Santo state, Brazil. They are described and named herein as follows: Anastrepha atlantica n. sp., Anastrepha glochin n. sp., Anastrepha linharensis n. sp. and Anastrepha martinsi n. sp. Only the latter was collected in traps hung in papaya orchards. The classification of these species in species groups of Anastrepha is also discussed.
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Gamasiphis paulista n. sp. is described based on specimens representing all postembryonic stages, collected from litter and soil in Piracicaba, State of Sao Paulo. This is the first species of Gamasiphis described from Brazil. A key is provided for the separation of species of this genus known from the Neotropical Region.
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Arrenoseius gaucho n. sp. is described from the State of Rio Grande do Sul, in southern Brazil, based on specimens collected on four plant species. A redescription of Arrenoseius tucumanensis (Sheals), the species most similar to A. gaucho n. sp., is provided based on the holotype.
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Proctolaelaps bulbosus n. sp. (Acari: Ascidae) is described from adult females and males of a laboratory colony derived from a collection from Cocos nucifera L. (Arecaceae) in northeastern Brazil. This species is distinguished from other Proctolaelaps species by the absence of the setae z3 and R3, knobbed seta Z5 and long spermatodactyl.
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Two new species of spider mites (Tetranychidae) found on Solanaceae in Peru are described: Tetranychus singularis n. sp. from Datura stramonium L. and T. amazonensis n. sp. from Solanum caricaefolium Rusby.
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This paper provides the description of Phaenocarpa neosilbae sp. n. (Braconidae: Alysiinae) reared from larvae of Neosilba perezi (Romero Ruppel, 1973) (Diptera: Lonchaeidae) in Brazil. Diagnostic characters are figured and the key to the Neotropical species of Phaenocarpa (Arouca Penteado-Dias, 2006) is modified to include the new species.
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A new species of eriophyoid mite, belonging in the genus Abacarus Keifer (Eriophyidae), causing damage to sugarcane, Saccharum officinarum L. (Poaceae), in Costa Rica is illustrated and described. Abacarus doctus n. sp. is the only eriophyoid species recorded so far with a tibial seta (l`) on the second pair of legs, an unexpected characteristic observed for the first time in the superfamily Eriophyoidea. Remarks on the phylogenetic and taxonomical aspects related to the presence of this seta are presented. Damage symptoms caused by this mite are presented as well as a key for Abacarus species described from sugarcane. In addition, the need to apply biosecurity procedures during sugarcane germplasm exchange to avoid dissemination of the new mite species is discussed.
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In this paper we present the description of five new species of tetranychid mites collected in south Tunisian oasis areas. These are: Bryobia alveolata sp. nov., Aplonobia crispipilis sp. nov., Petrobia (Petrobia) carthagensis sp. nov., Petrobia (Petrobia) pseudotetranychina sp. nov. and Tetranychus (Tetranychus) atriplexi sp. nov. The notion of dorsal tubercles used to separate the sub-genera Tetranychina from Petrobia sensu stricto and Mesotetranychus among the genus Petrobia is also discussed.
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Aeration and agitation are important variables to ensure effective oxygen transfer rate during aerobic bioprocesses: therefore, the knowledge of the volumetric mass transfer coefficient (k(L)a) is required. In view of selecting the optimum oxygen requirements for extractive fermentation in aqueous two-phase system (ATPS), the k(L)a values in a typical ATPS medium were compared in this work with those in distilled water and in a simple fermentation medium. in the absence of biomass. Aeration and agitation were selected as the independent variables using a 2(2) full factorial design. Both variables showed statistically significant effects on k(L)a, and the highest values of this parameter in both media for simple fermentation (241 s(-1)) and extractive fermentation with ATPS (70.3 s(-1)) were observed at the highest levels of aeration (5 vvm) and agitation (1200 rpm). The k(L)a values were then used to establish mathematical correlations of this response as a function of the process variables. The exponents of the power number (N(3)D(2)) and superficial gas velocity (V(s)) determined in distilled water (alpha = 0.39 and beta = 0.47, respectively) were in reasonable agreement with the ones reported in the literature for several aqueous systems and close to those determined for a simple fermentation medium (alpha=0.38 and beta=0.41). On the other hand, as expected by the increased viscosity in the presence of polyethylene glycol, their values were remarkably higher in a typical medium for extractive fermentation (alpha=0.50 and beta=1.0). A reasonable agreement was found between the experimental data of k(L)a for the three selected systems and the values predicted by the theoretical models, under a wide range of operational conditions. (C) 2009 Elsevier B.V. All rights reserved.
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By considering controversial discussions in the literature with regard to gland denomination in Indigofera species, as well as the taxonomic value of secretory structures in Leguminosae, we aim to morphologically detail glands that had been previously observed in I. microcarpa and I. sabulicola, and to investigate the occurrence of glands in vegetative and reproductive organs of other six Neotropical species that belong to the genus. Glands analyzed through scanning electronic microscopy (SEM) in combination with anatomic analyses correspond to secretory trichomes that Lire classified into seven types. Main variations in relation to types occurred with regard to head shape and peduncle size. Trichome heads were multicellular, with a thin cuticle. Hollow heads with conspicuous inner space characterized only one type (type I); the other trichome types had massive heads. Peduncles, which varied from biseriate to multiseriate, had thick, pecto-cellulosic cell walls. Trichomes were found on sterns, stipules, petioles, rachis, petiolules, leaflets, bracteoles, sepals, standards and fruits, more commonly along the margins. Each of the eight Indigofera species analyzed had at least two different trichome types out of the seven types that occurred in reproductive and vegetative organs of these taxa. Various types of secretory trichomes were found in I. campestris, I. lespedezioides, I. microcarpa, I. spicata. I. Suffruticosa and I. truxillensis. Stems and rachis were the vegetative organs in which a greater variety of trichomes occurred, and sepals were parts of reproductive organs with the same status. Five out of the seven secretory trichome types occurred on both vegetative and reproductive organs. Distribution and gland types differed between species and these gland distribution patterns can be used as diagnostic characters. Reports of glands in Indigofera campestris, I. hirsuta, I. lepedezioides, I. suffruticosa, I. spicata and I. truxillensis, their recognition as secretory trichomes. and the morphological variety of types found for such trichomes are novel data for Indigofera. (C) 2008 Elsevier GmbH. All rights reserved.
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LEITE, V. G., F. S. MARQUIAFAVEL, D. P. MORAES, AND S. P. TEIXEIRA (Departamento de Ciencias Farmaceuticas, Faculdade de Ciencias Farmaceuticas de Ribeirao Preto, Universidade de Sao Paulo (USP), Av. do Cafe, s/n, 14040-903 Ribeirao Preto, SP, Brazil). Fruit anatomy of Neotropical species of Indigofera (Leguminosae, Papilionoideae) with functional and taxonomic implications. J. Torrey Bot. Soc. 136: 203-211. 2009-This work reports on the fruit surface and anatomy of seven Neotropical species of Indigofera (I. campestris Bong. ex Benth., I. hirsuta L., I. lespedeziodes Kunth, I. microcarpa Desv., I. spicata Forssk., I. suffruticosa Mill., and I. truxillensis Kunth) to help species diagnosis and clarify the fruit type classification. Flowers and fruits at several stages of development were removed from living material, fixed, and examined with scanning electron (surface analyses) and light microscopies (histological analyses). Species showed differences in relation to the number of exocarp layers, secretory trichome morphology and distribution, presence of stomata, phenolic idioblast size and distribution in mesocarp, the number and arrangement of endocarp fibers, and the presence of it separation tissue. It is noteworthy that no separation tissue was observed in L microcarpa and I. suffruticosa, although they have dehiscent fruits, which indicates it delayed dehiscence. The present work confirms that fruit anatomical characters can be utilized as it tool for fruit type classification, especially in Indigofera, the third largest genus of Leguminosae.
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The Miconia genus, a plant widely used for medicine, occurs in tropical America and its extracts and isolated compounds have demonstrated antibiotic, antitumoral, analgesic and antimalarial activities. However, no study concerning its genotoxicity has been conducted and it is necessary to determine its potential mutagenic effects to develop products and chemicals from these extracts. This study assessed the cytotoxicity, mutagenicity and the protective effects of methanolic extracts from Miconia species on Chinese hamster lung fibroblast cell cultures (V79). The cytotoxicity was evaluated using a clonogenic assay. Cultures exposed to the extract of Miconia albicans up to a concentration of 30 mu g/mL, M. cabucu up to 40 mu g/mL, M. albicans up to 40 mu g/mL and M. stenostachya up to 60 mu g/mL exhibited a cytotoxic effect on the cells. The clonogenic assay used three non-cytotoxic concentrations (5, 10 and 20 mu g/mL) to evaluate mutagenicity and antimutagenicity of the extracts. Cultures were treated with these three extract concentrations (mutagenicity test) or the extract associated with doxorubicin (DXR) (antimutagenicity test) in three protocols (pre-, simultaneous and post-treatments). Distilled water and DXR were used as negative and positive controls, respectively. In the micronucleus (MN) test, a significant reduction was observed in MN frequency in cultures treated with DXR and extracts compared to those receiving only DXR; a significant reduction was also observed for the presence of mutagenicity in all treatments. This study confirmed the safe use of Miconia extracts at the concentrations tested and reinforced the therapeutic properties previously described for Miconia species by showing their protective effects on doxorubicin-induced mutagenicity. (C) 2010 Elsevier GmbH. All rights reserved.
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Colloidal PbS nanocrystals over-coated with CdS are prepared in aqueous solutions and exhibit strong photoluminescence with two distinct peaks in the visible regime. A photoluminescence peak is observed at 640 nm, which is attributed to the band edge recombination in the PbS nanocrystals, and another peak at 510 nm, which is above the band edge of the PbS nanocrystals. The two PL peaks are isolated by extracting separate species of nanocrystal based upon their surface morphology. Micro-emulsions of hexane:PVA are used to remove the species containing the PL peak at 640 nm from the solution, leaving a singular peak at 510 nm. We show conclusively that the double-peaked structure observed in the photoluminescence spectra of PbS nanocrystals over-coated with CdS is due to the presence of two distinctly different nanocrystal species.
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Marine invertebrate sperm proteins are particularly interesting because they are characterized by positive selection and are likely to be involved in prezyogotic isolation and, thus, speciation. Here, we present the first survey of inter and intraspecific variation of a bivalve sperm protein among a group of species that regularly hybridize in nature. M7 lysin is found in sperm acrosomes of mussels and dissolves the egg vitelline coat, permitting fertilization. We sequenced multiple alleles of the mature protein-coding region of M7 lysin from allopatric populations of mussels in the Mytilus edulis species group (M. edulis, M. galloprovincialis, and M. trossulus). A significant McDonald-Kreitman test showed an excess of fixed amino acid replacing substitutions between species, consistent with positive selection. In addition, Kolmogorov-Smirnov tests showed significant heterogeneity in polymorphism to divergence ratios for both synonymous variation and combined synonymous and non-synonymous variation within M. galloprovincialis. These results indicate that there has been adaptive evolution at M7 lysin and, furthermore, shows that positive selection on sperm proteins can occur even when post-zygotic reproductive isolation is incomplete.
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Two new genera and four new species of monorchiid digeneans are described from the Great Barrier Reef and Moreton Bay, Queensland. Provitellus turrum n. g., n. sp. from Pseudocaranx dentex and Trachinotus coppingeri is characterised by the presence of vitelline follicles in the forebody, a single testis, a unipartite terminal organ and filamented eggs. Ovipusillus mayu n. g., n. sp. from Gnathanodon speciosus is characterised by the presence of two testes, vitelline follicles overlapping the ventral sucker and a large, complex cirrus-sac that contains a coiled eversible ejaculatory duct joined by the pars prostatica halfway along its length. Paramonorcheides pseudocaranxi n. sp. from Pseudocaranx dentex differs from other species described in this genus in the longer flatter forebody, entire ovary and the well-developed cirrus-sac. Chrisomon gaigai n. sp. from Trachinotus coppingeri and T botla is characterised by the unflattened forebody and transversely oval pharynx. Chrisomon is redefined to include species of Lasiotocus with a vitellarium composed of clusters of tubular acini, creating the following new combinations: C. albulae n. comb. for L. albulae Overstreet, 1969, C. ulua n. comb, for L. ulua Yamaguti, 1970 and C. weke n. comb, for L. weke Yamaguti, 1970. The diagnosis of Lasiotocus is amended accordingly and the new combinations, L. polynemi n. comb. and L. sunderbanensis n. comb., are created for C.polynemi Dutta, Hafeezullah & Manna, 1994 and C. sunderbanensis Dutta, Hafeezullah B Manna, 1994, respectively. Extrapolation of our collection data suggests that there may be as many as 80 species of monorchiids infecting carangid fishes in Australia and 180 species infecting carangids in all oceans of the world. The latter figure greatly exceeds the number of monorchiids described from all host families to date.