Anfíbios Anuros do Distrito Federal

The frogs of the Federal District of Brazil are listed and discussed as to habit, biology and ecology. The F. D is situated 22° 54' 24" S. & 43° 10' 21" W Gr. and comprises 1.356 km². Its topography includes sea-shore, maritime scrub, lagoons, plains and marsh, open slopes, forested mountains and great heads of rock. Three thousand feet of altitude are attained at two points. Fifty two different frogs occur in the F.D. Three fifths of them live in open country. Two fifths of these have never been found above the plains; the others range higher but mostly in open country. Their environment offers conditions suitable for average tadpoles and adults. these frogs are more or less unspecialized. There are six genera and thirty species. Two thirds of the latter belong to the type genera of the large neotropical families Bufonidae, Leptodactylidae and Hylidae. Only in the maritime scrub formation are conditions somewhat different. Water for average tadpoles is provided by the lagoons. The xerophytism of the vegetation is, however, so marked that bromeliads growing on the ground provide almost the only appropriate shelter for adult tree-frogs used to sleeping upright on the vegetation. One large Hylid genus lives entirely in them. It is casque-headed and phragmotic, shutting the lumen of the leaf-cup with head used as a plug. Another large Hylid genus shows a lesser degree of the same specialization. (Lutz A & Lutz B, 1939 II). One genus with two species is entirely saxicolous; it lives on wet ledges of rock at all phases of its life history. (B. Lutz 1948). The other two fifths of the frogs from F. D. are montane forest forms. Their environment offers numerous and varied biotopes and is near optimum for adults. There is,however, hardly any standing water available for larvae. These frogs are ecologically diversified. They also show a general trend towards spawning in the adult biotipe, which leads to delayed hatching, semi-aquatic and terrestrial larvae and direct development. (B Lutz, 1948). The author interprets the morphological specialization of the casque-headed Hylids and the biological specialization of the montane forest forms as adaptive. Casque-headedness and phragmosis increase protection against blood-suckers and predators. The humidity of the rain forest permits eggs, embryos and larvae to develop, unharmed, outside their usual, aquatic, environment.

Can competition in the credit market be excessive?

We study how market power affects investment and welfare when banks choose between restricting loan sizes and monitoring, in order to alleviate an underlying moral hazard problem. The impact of market power on aggregate welfare is the result of two countervailing effects. An increase in banks' market power results in: (i) higher lending rates, which worsens the borrower's incentive problem and reduces investment by unmonitored firms, (ii) higher monitoring effort, which reduces the proportion of credit-constrained firms. Whenever the second effect dominates, it is optimal to provide banks with some degree of market power.

Taxation of banks: a theoretical framework

The goal of this paper is to develop a model of financial intermediation analyze the impact of various forms of taxation. The model considers in a unified framework various functions of banks: monitoring, transaction services and asset transformation. Particular attention is devoted to conditions for separability between deposits and loans. The analysis focuses on: (i) competition between banks and alternative financial arrangements (investment funds and organized security markets), (ii) regulation, and (iii) bank's monopoly power and risk taking behavior.

Investigações sôbre infecções por enterovírus no Distrito Federal

Os autores descrevem os resultados de investigações realizadas pelo Instituto Oswaldo Cruz, com material colhido pelo Serviço de Epidemiologia de Brasília, de casos paralíticos, durante um periódo de 13 meses (janeiro de 1964 a janeiro de 1965). De um total de 47 materiais examinados, foram isoladas 28 amostras de Polivírus do tipo 1, 4 do tipo 2 e duas não-pólio. Destas, uma mostrou-se patogênica para o camundongo recém-nascido, onde as lesões histopatológicas foram compatíveis com as reproduzidas por uma amostra do grupo Coxsackie A. A distribuição por idade dos pacientes sugere a necessidade de serem os grupos etários de até, no máximo, 4 anos de idade, os que devem ser fundamentalmente atingidos por campanhas de imunização contra a poliomielite, na região estudada.

An analysis of strategic paths through the decomposition of total factor productivity: the case of Spanish savings banks

The Spanish savings banks attracted quite a considerable amount of interest within the scientific arena, especially subsequent to the disappearance of the regulatory constraints during the second decade of the 1980s. Nonetheless, a lack of research identified with respect to mainstream paths given by strategic groups, and the analysis of the total factor productivity. Therefore, on the basis of the resource-based view of the firm and cluster analysis, we make use of changes in structure and performance ratios in order to identify the strategic groups extant in the sector. We attain a threeways division, which we link with different input-output specifications defining strategic paths. Consequently, on the basis of these three dissimilar approaches we compute and decompose a Hicks-Moorsteen total factor productivity index. Obtained results put forward an interesting interpretation under a multi-strategic approach, together with the setbacks of employing cluster analysis within a complex strategic environment. Moreover, we also propose an ex-post method of analysing the outcomes of the decomposed total factor productivity index that could be merged with non-traditional techniques of forming strategic groups, such as cognitive approaches.

Simuliidae of Goiás state and the Federal District (Brasília): 1. A description of Simulium (Chirostilbia) dekeyseri, new species

A new Brazilian simuliid species, Simulium (Chirostilbia) dekeyseri, is described from reared adults as well as larvas and pupae. This zoophilic species has only been recorded from localities in the Cerrado region of the Central Brazilian Plateu.

When do central banks prefer to intervene secretly?

Central banks often intervene secretly in the foreign exchange market. This secrecy seems to be at odds with the signalling channel. In this article we will analyse when a central bank intervening in the foreign exchange rate market purely through the signalling channel would prefer to act secretly or publicly. By using a microstructure model, we will show that the consistency of the intervention with fundamentals, the volume of noise trading, the weight given to the effectiveness of intervention and the degree of superior information held by the central bank will influence the decision to intervene secretly or publicly. Keywords: foreign exchange intervention, market microstructure. JEL Classifi…cation: D82, E58, F31, G14.

Mansonella ozzardi no Território Federal de Roraima, Brasil: distribuição e achado de um novo vetor na área do rio Surumu

Um inquérito hemoscópico, conduzido entre indígenas Makuxi, pertencentes a 15 localidades da região nordeste do Território Federal de Roraima, revelou a presença de microfilárias de Mansonella ozzardi em 3,2% das 652 pessoas examinadas. O número de microfilárias nos positivos era pequeno, não ultrapassando a 18 nas amostras de sangue(20mm3) colhidas. A baixa densidade na microfilaremia e a inexistência da infecção em menores de 15 anos sugerem que a filariose está sendo adquirida pelos indígenas fora de suas aldeias, provavelmente nos garimpos de ouro situados na parte alta do rio Maú. Simulium oyapockense s.l. ou Simulium roraimense - espécie muito espalhada no norte do Território - foi reconhecido como vetor de M. ozzardi na área do rio Surumu. As fêmeas desse simulídeo, embora capazes de suportar o desenvolvimento da filária até L3, não se infectam com facilidade. Assim, numa tentativa de infecção experimental, apenas 20,6% das fêmeas alimentadas sobre um voluntário (com 12mf/20mm3 de sangue colhido da polpa digital) exibiram estádios larvares de M. ozzardi (1-2 larvas somente por exemplar infectado). A alta prevalência em índios Sanumá e Mayongong, que vivem no lado oposto do Território, aponta para a existência, na área do rio Auaris, onde se localizam esses indígenas, de um outro vetor, muito mais eficiente do que S. oyapockense s.l.