36 resultados para Masefield, John, 1878-1967
Resumo:
Modificações na expressão gênica foram observadas nos sistemas esterase, leucina aminopeptidase e x-glicerofosfato desidrogenase, durante o desenvolvimento ontogenético de Anopheles albitarsis. A esterase revelou quatro regiões de atividade, sendo a esterase 1 detectada apenas em larvas de 4º estádio velhas e em pupas, as esterases 2 e 4 foram presentes durante todo o desenvolvimento, e a esterase 3 revelou-se praticamente apenas em larvas e raríssimas vezes em pupas. Também foram observadas quatro regiões de atividade na leucina aminopeptidase, durante a ontogenia. As LAP1 c LAP2 foram características de larvas, a LAP3 esteve presente somente em pupas e adultos e a LAP4 foi detectada nos três diferentes estágios. Uma única região foi observada para a x-glicerofosfato desidrogenase e a intensidade de sua atividade cresce à medida que se aproxima o estágio adulto.
Resumo:
There is considerable confusion in the literature regarding the systematic position and distribution of two pseudothelphusid crabs originally described as Potamocarcinus reflexifrons Ortmann, 1897 and Potamocarcinus reflexifrons fittkaui Bott, 1967, and now included in the genus Fredius Pretzman, 1965, as F. reflexifrons and F. fittkaui. Study of numerous specimens from recent collections, together with a critical analysis of the data published in the literature, shows that both taxa could be easily separated by gonopodal characters. The two species occupy discrete areas of distribution along the main axis of the Amazon River and in the upper Rio Negro Basin, respectively, with an overlap in the Atlantic Guianas. It is postulated that they originated from a common ancestor, through a process of vicariance, in the two areas observed at present. Permeability of barriers allowed their further occupancy of the Atlantic Guianas after the marine regressions in this area.
Resumo:
Os dados obtidos durante os anos de 1967 a 1971 (2 biênios: 1967/1968 e 1670/1971) no cafèzal da E.S.A. "Luiz de Queiroz", parte sombreada e parte a pleno sol, foram estudados no presente trabalho, complementando aqueles de sete biênios já descritos em trabalhos anteriores. Os resultados obtidos, analisados estatisticamente em relação à produção, porcentagem de broca, porcentagem de frutos verdes, de maduros e de sêcos, rendimento de café da roça, relação café beneficiado/café coco e peneira média, permitiram as conclusões seguintes, principalmente em relação aos biênios estudados: a. o lote sombreado, em relação a um dos lotes não sombreado, apresentou diferenças significativas quanto à produção, em favor para o sombreado; isso se deve provavelmente ao fato de as plantas de sombra estarem agora em decadência com muitas árvores mortas, favorecendo o lote sombreado pela luz e pela matéria orgânica acumulada; b. a porcentagem de broca continuou a ser, em geral, sempre maior nos lotes sombreados; c. as porcentagens de frutos verdes, de maduros e de sêcos dependem, em geral, do ano e da época da colheita.
Resumo:
Anopheles (Nyssorhynchus) albitarsis Lynch-Arribalzaga, 1878 shows morphological and behavioural variations which results in it being sometimes considered as a major malaria vector and at other times as playing no important role in epidemiology. With the aim of clarifying the taxonomy of the species, comparative morphological and isoenzymatic studies were made in populations from the type-locality, Baradero, Argentina and from 9 different localities inBrazil. Morphological studies consisted of the observation of eggs in scanning electron microscopy, of complete chaetotaxy of larvae and pupae and of the detailed drawing of male and female adults. Only Guajara-Mirim and Rio Branco populations, described previously as Anopheles deaneorum sp.n., showed morphological differences. Isoenzymes were studied using 4th instar larvae homogenate and agarosegel electrophoresis. Eleven enzymatic loci were analyzed. By calculation of Nei's Genetic Distance (D), the populations could be separated into 5 groups: i)Baradero, ii)Marajo, iii)Boa Vista, iv)Angra, Itaguai and Paraipaba and v)Guajara-Mirim and Rio Branco. These groups belong to 2 major clusters called I and II, separated by D = 0.345. In the I cluster are groups i, ii and iii and in II clusteriv and v. In I, D=0.246 separates i and ii from iii, while i is separated by D =0.181 from ii. In II, D = 0.223 between iv and v. Only the population of group vcould be distinguished morphologically from the others, leading to the description of an independent species An. deaneorum.
Resumo:
Searching and handling time of Chrysoperla externa (Hagen, 1861) (Neuroptera, Chrysopidae) larvae fed on Uroleucon ambrosiae (Thomas, 1878) (Hemiptera, Aphididae). The objective of this research was to determine the searching and handling times of three larval instars of C. externa fed on U. ambrosiae at densities of 30, 40 and 50 per vial, with the feeding of the larvae at the preceding instars being U. ambrosiae nymphs or Sitotroga cerealella (Olivier, 1819) eggs. The larvae were maintained at 25 ± 2 ºC, 70 ± 10% RH and a 14-h photophase. A completely randomized design in a 6 x 3 factorial scheme with 12 replicates was adopted. The shortest searching time was found for the 2nd and 3rd instar larvae of C. externa, and this parameter was variable depending on the feeding given to the larvae previously. The handling time was similar for the 1st, 2nd and 3rd instar larvae. The longest searching time was found at an aphid density of 30, as compared to densities of 40 and 50 prey, with which there were no significant differences. Prey density did not have any influence on handling time.
Resumo:
Feeding potential of Chrysoperla externa (Hagen) (Neuroptera, Chrysopidae) in different densities of Uroleucon ambrosiae (Thomas) (Hemiptera, Aphididae). The feeding potential of 2nd and 3rd instar larvae of Chrysoperla externa (Hagen, 1861) in relation to different densities of 30, 40 and 50 nymphs of Uroleucon ambrosiae (Thomas, 1878) at 3rd and 4th instars was evaluated. The treatments were individualized into 2.5 cm in diameter and 8.5 cm tall flat bottom glass vials and maintained in a controlled environmental chamber at 25±2 ºC temperature, 70±10% RH and 14 h photophase. A completely randomized experimental design with 10 replications was used. The consumption of the prey nymphs by the predator larvae was evaluated after 1, 2, 4, 8, 16 and 24 h from the beginning of the experiment and at every subsequent 24 h period until 2nd instar larvae molted or 3rd instar larvae pupated. Results have shown that for 2nd instar larvae, during the 1 h to 24 h period, there was a decreasing prey consumption at the 30 and 40 prey densities. However an increase in the consumption at the 50 prey density was observed. After this period, C. externa larvae presented a progressive increase on nymphs consumption as a function of the prey density. The same occurred with de 3rd instar predator larvae in all treatments. When daily mean consumption was evaluated the predator/prey ratio was 1:23, 1:27 and 1:33 for 2nd instar larvae and 1:27, 1:33 and 1:41 for 3rd instar larvae at 30, 40 and 50 nymph densities, respectively.
Resumo:
Em sintonia com os princípios democráticos inspirados pela filosofia educacional de John Dewey, Anísio Teixeira foi construindo ao longo das suas atividades na vida pública, o que neste artigo se chamou de ideário pedagógico municipalista. O artigo apresenta essa trajetória pública: Bahia (1924 - 1929); Distrito Federal (1931 - 1935); Bahia (1947 - 1951); Rio de Janeiro (1952 - 1961); Rio de Janeiro (1962 - 1968); Brasília (1963- 1964); Rio de Janeiro (1967 - 1970).
Resumo:
A résumé of the evolution of quantum chemistry methodologies is presented. The pioneering contributions of John A. Pople and Water Kohn, the 1998 Nobel Prize Laureates in Chemistry, to the development of quantum chemistry computational methods for studying the properties of molecules and their interaction is discussed.
Resumo:
John Locke é conhecido, sobretudo, por ser um dos fundadores do liberalismo. No entanto, pesquisas recentes apontam para novas interpretações do pensador inglês. No caminho dessa tendência, o objetivo deste texto é analisar os elementos republicanos na "Carta sobre a tolerância" de Locke.
Resumo:
RESUMO - (Fitossociologia de um remanescente de mata mesófila semidecídua urbana, Bosque John Kennedy, Araguari, MG, Brasil). Um estudo fitossociológico foi realizado no Bosque Municipal John Kennedy, município de Araguari, MG (48°11'19''W e 18°38'35''S). O bosque, com aproximadamente 11,2 ha, situa-se no perímetro urbano e é formado principalmente por uma mata mesófila semidecídua. No levantamento fitossociológico realizado, amostraram-se, em 1,2 ha, 1827 indivíduos, pertencentes a 46 famílias; 88 gêneros e 113 espécies, com um índice de diversidade de Shannon de H' = 3,75 nats/indivíduo. Os parâmetros fitossociológicos indicam as espécies mais importantes: Licania apetala, Micrandra elata, Copaifera langsdorffii, Astronium nelson-rosae e Alchornea glandulosa, e as famílias mais importantes: Chrysobalanaceae, Euphorbiaceae, Caesalpinaceae, Mimosaceae e Anacardiaceae. A ocorrência de algumas espécies incluidas entre as principais, caracteristicamente, pioneiras (Alchornea glandulosa e Piptocarpha macropoda), ou secundárias (Didymopanax macrocarpum e Maprounea guianensis), pode ser explicada pela existência de algumas áreas de clareiras, no interior dessa mata semidecídua, mas que, aparentemente, ainda não interferiram na estrutura da mata como um todo.
Resumo:
The paper has analyzed John R. Commons' contribution to the comprehension of Law and Economics relationship. In contrast to the orthodox economics, Commons has shown that the capitalist economic order emerges and functions regulated by laws and institutions. These approaches made possible to him to understand the nature of the modern capitalist wealth and the problems that time introduces in economic transactions.