Abstract: The Lower Cretaceous (Aptian-Albian) sedimentary rocks of the Araripe Plateau, northeast interior of Brazil, are truncated by a regional unconformity. This erosional unconformity, observed during field work and later recognized in cores, is here described for the first time. This erosion gave rise to partial dissolution of the evaporitic rocks (gypsum and anhydrite) of the Araripina Formation, originating a karst topography, Following this episode of karst formation, a calcrete layer developed. The calcrete is composed of calcareous and siliceous laminar crusts capping algal shales. The presence of associated karst and calcrete registers a climatic fluctuation between wet and dry periods in the basin.

Abstract: We apply a Position Space Renormalization Group approach to the Ising Hamiltonian in a square lattice with first (J 1 ) and second (J 2 ) neighbour exchange interactions. The full phase diagram is obtained with three distinct ordered phases: ferro (F), antiferro (AF) and superantiferromagnetic (SAF). In particular, in the last one, the competing interactions J 1 and J 2 Application, d'une approche de groupe de renormalisation dans l'espace direct a un hamiltonien d'Ising avec interactions de proches (J 1 ) et seconds (J 2 ) voisins. Obtention du diagramme de phases complet avec 3 phases ordonnees: ferromagnetique, antiferromagnetique et superantiferromagnetique. Dans cette 3eme phase, role crucial des interactions concurrentes J 1 >0 et J 2 <0, entrainant une degenerescence d'ordre 2 des etats fondamentaux (attracteur avec bifurcation d'ordre 2). Caractere non universel de la transition superantiferromagnetique-paramagnetique

Abstract: The Araripe Basin in northeastern Brazil contain a 700 m-thick succession of JurassIc-Cretaceous strata. The 200 m-thick Lower Cretaceous is widely known for its fish-bearing concretions and gypsum deposits. Detailed field studies and core analyses provided data for revision of the Lower Cretaceous stratigraphy in the Araripe Basin. A regional disconfonnity within the Lower Cretaceous succession is described here for the flrst time. This surface divides the Aptian-Albian succession into two parts : 1. a lower sequence of black shale, laminated carbonate, algal mat carbonates, and evaporites in ascending stratigraphic order; and 2. an overlying sequence containing concretionary shale, limestone, and sandstone. These two stratigraphic divisions are herein defined as the Araripina Formation (new name) and the Santana Formation (revised), respectively. The expression of the disconformity varies across the basin. ln the southwest it is marked by caves formed in the gypsum and a karstic topography. Toward s the northeast, a 50 cm-thick layer of laminar calcareous and siliceous calcrete crust mark s th e disconformity surface.

Abstract: Marx’s thoughts about money and its role in capitalist economies are scattered throughout his works. In particular, they constitute a major part of the 3rd volume of Capital and of the Grundrisse. In these two works, Marx presents the foundations for a theory of money that is very dose to Keynes’s views. In the paper this similarity is shown through the systematization of Marx’s monetary theory along (post) Keynesian lines. Thc demand for money is shown to be rooted not only in the transactions motive but also in the liquidity properties of money. These properties become important in capitalist economies characterized by market uncertainty. Both Marx and Keynes use the concept of money to break Say’s law. An essential difference between the two authors is shown to relate to the measure-of-value function of money and ways to reconcile them on this issue are developed.

Abstract: A 3% efficiency, crossed-field type, N2 laser (337.1 nm) has been developed, based on very low inductance circuits (coaxial configuration) and a careful selection of their resonance frequencies.

Abstract: Solutions to increasing environmental problems in Latin America require professionals trained in the interdisciplinary area of environmental sciences. However, such training is difficult to achieve in a traditional discipline-oriented curriculum. This paper describes a graduate field course taught in Brazil that uses the system concept and the geochemical cycle as unifying paradigms to study environments that range from rock outcrops and rain forests to mangroves and aquaculture experiments. The course emphasizes acquiring the techniques of integrated observation, using such intellectual tools as operational definitions, measurement scales, and a priori hypotheses. The overall objective is to help students learn how to analyze diverse environmental systems, a necessary first step for comprehensive land use management.

Abstract: The Green's-function method in the random-phase approximation is applied to calculate the magnetization of the (111) surface planes on both sides of an interface between two semi-infinite Heisenberg ferromagnets with a face-centered-cubic structure. Both bulk systems are chosen with anisotropic exchange interactions. When there is an appreciable difference in the transition temperatures of both sides, one finds that the stronger ferromagnet induces a permanent magnetization in the weaker one, which can be sustained at temperatures higher than the transition temperature of the latter. Several branches of surface magnons are also found.

Abstract: A retrospective study was carried out on the type of habitual diet consumed in the Niteroi (Rio de Janeiro) city Two groups of subjects were integrated: the Experimental Group, formed by patients with neoplasms of the large intestine and rectum, and the Control Group, formed by individuals with no gastrointestinal disorders The information obtained through direct inquiry, strongly suggests that cancer of the colon and rectum may be related to the high proportion of fat and low proportion of dietary fiber found in the diets of the patients studied

Abstract: Observation chez un homme de 30 ans. Le diagnostic est fait par biopsie ganglionnaire, les auteurs commentent le diagnostic differentiel d'avec la tuberculose pulmonaire et les hemopathies, et discutent la pathogenie de l'epanchement

Abstract: The electroencephalographic (EEG) findings observed in nine patients with post-anoxic myoclonic encephalopathy are reported. The tracings showed typical myoclonus potencial in some, and characteristic diffuse brain injury in others. In two of our cases the spike and wave complex was faster than in the others. Our EEG tracings are similar to those studied by Gastaut and Remond in 1952.

Abstract: Before exploring the specific subject of this chapter, I would like to briefly survey the cultural background, not only of Brazil but of Latin America in general, in which the study of semiotics has emerged. Portuguese and Spanish colonization, imposed upon an indigenous population and then mixed with African Negro blood, gave rise to a Latin American civilization still known throughout the world as underdeveloped and belonging economically to the Third World. Although Brazil has problems quite different from its Spanish American neighbors, the basic sociocultural aspects have been the same, varying only according to the political moment. Over the centuries cultural models from Europe were also imposed upon Latin America, often via the colonizing power which had interpreted the models according to its own needs.

Abstract: The surface magnetization and electron concentration are calculated for a tight-binding, single-orbital model of a transition metal in the Hartree-Fock approximation, for a (111) surface in the f.c.c. structure and a (100) surface in a s.c. one. Local Green’s functions at the surface plane and in the bulk are expressed as continued fractions through the transfer matrix approach. Self-consistency plus constraints of local charge neutrality and equality of surface and bulk chemical potentials determine the surface intra-atomic HubbardUs and chemical shift Δe of surface orbitals. The self-consistent equations were solved graphically by recourse to the integrated density of states for bulk or surface. The method is applied to systems with parameters adequate for Ni and Fe.

Abstract: A case of a young man with myoclonus in his right side after cerebral hypoxia is reported. This patient had cerebral hypoxia caused by injury in his left common carotid artery. After a few hours he had generalized convulsive seizures of tonic-clonic type and also a septic shock. As consciousness was regained, he developped action and intention myoclonus in his right-side. The EEG showed difuse typical myoclonus potentials. Clonazepan 8mg daily was used with good results. This is the first reference in the medical literature of the unilateral localization in the Lance-Adams syndrome. The authors think that in this case two abnormalities contributed to the cerebral anoxia: the common carotid artery injury and the sepctic shock.