Estratigrafia de sequências do intervalo aptiano ao albino na Bacia do Araripe, NE do Brasil

This study has as a main objective to make a detailed stratigraphic analysis of the Aptian-Albian interval in the east part of Araripe Basin, NE of Brazil which correspond, litostratigraphically, to Rio Da Batateira, Crato, Ipubi and Romualdo formations. The stratigraphic analysis was based on three different stages, the 1D, 2D and 3D analysis; these ones were adapted to the sequence stratigraphy concepts in order to create a chronostratigraphic framework for the study area within the basin. The database used in the present study contains field and well information, wells that belong to Santana Project, carried out by the Ministério de Minas e Energia- DNPM- CPRM from 1977 to 1978. The analysis 1D, which was done separately for each well and outcrop allowed the recognition of 13 sedimentary facies, mainly divided based on predominant litologies and sedimentary structures. Such facies are lithologically represented by pebble, sandstones, claystones, margas and evaporates; these facies are associated in order to characterize different depositional systems, that integrate from the continental environment (fluvial system and lacustre), paralic system (delta system and lagunar) to the marine environment (shelfenvironment). The first one, the fluvial system was divided into two subtypes: meandering fluvial system, characterized by fill channel and floodplain deposits; the facies of this system are associated vertically according to the textural thinning upward cycles (dirting-up trend pattern in well logs). Lacustrine environment is mainly related with the lithotypes of the Crato Formation, it shows a good distribution within the basin, been composed by green claystone deposits and calcareous laminated. Deltaic System represented by prodelta and delta front deposits which coarsening upward tendency. Lagunar system is characterised by the presence of anhydrite and gypsum deposits besides the black claystone deposits with vegetal fragments which do not contain a fauna typically marine. The marine platform system is composed by successions of black and gray claystone with fossiliferous fauna of Dinoflagellates (Spiniferites Mantell, Subtilisphaera Jain e Subtilisphaera Millipied genre) typical of this kind of depositional system. The sedimentary facies described are vertically arranged in cycles with progradational patterns which form textural coersening upward cycles and retrogradational, represented by textural thinning dowward cycles. Based in these cycles, in their stack pattern and the vertical change between these patterns, the systems tracks and the depositional sequences were recognized. The Low System Track (LST) and High System Track (HST) are composed by cycles with progradational stack pattern, whereas the Trangessive System Track (TST) is composed by retrogradational stack pattern cycles. The 2D stratigraphic analysis was done through the carrying out of two stratigraphic sections. For the selection of the datum the deepest maximum flooding surface was chosen, inside the Sequence 1, the execution of these sections allowed to understand the behaviour of six depositional systems along the study area, which were interpreted as cycles of second order or supercycles (cycles between 3 and 10 Ma), according to the Vail, et al (1977) classification. The Sequence 1, the oldest of the six identified is composed by the low, transgressive and high systems tracks. The first two system tracks are formed exclusively by fluvial deposits of the Rio da Batateira Formation whereas the third one includes deltaic and lacustrine deposits of the Crato Formation. The sequences 2 and 3 are formed by the transgressive systems tracks (lake spreading phase) and the highstand system track (lake backward phase). The TST of these sequences are formed by lacustrine deposits whereas HST contains deltaic deposits, indicating high rates of sedimentary supply at the time of it s deposition. The sequence 4 is composed by LST, TST and HST, The TST4 shows a significant fall of the lake base level, this track was developed in conditions of low relation between the creation rate of space of accommodation and the sedimentary influx. The TST4 marks the third phase of expansion of the lacustrine system in the section after the basin´s rift, the lacustrine system established in the previous track starts a backward phase in conditions that the sedimentary supply rate exceeds the creation rate of space accommodation. The sequence 5 was developed in two different phases, the first one is related with the latest expansion stage of the lake, (TST5), the basal track of this sequence. In this phase the base level of the lake rose considerably. The second phase (related to the TST5) indicates the end of the lacustrine domain in the Araripe Basin and the change to lagunar system ant tidal flat, with great portions in the supratidal. These systems were formed by restricted lagoons, with shallow level of water and with intermittent connections with the sea. This, was the phase when the Araripe Basin recorded the most several arid conditions of the whole interval studied, Aptian Albian, conditions that allow the formation of evaporitic deposits. The sequence 6 began its deposition after a significant fall of the sea (LST6). The sequence 6 is without any doubtlessly, the sequence that has deposits that prove the effective entrance of the sea into the Araripe Basin. The TST6, end of this sequence, represents the moment which the sea reaches its maximum level during the Aptian Albian time. The stratigraphic analysis of the Aptian Albian interval made possible the understanding that the main control in the development of the depositional sequences recognized in the Araripe Basin were the variations of the local base level, which are controlled itself by the climate changes

O graben de Palestina: contribuição à estratigrafia e estrutura do estágio rifte na bacia do Araripe, nordeste do Brasil

The Palestina Graben is one of the NE-trending asymmetric grabens of the Araripe Basin. This basin rests on the precambrian terrains of the Transversal Zone, Borborema Province, immediately to the south of the Patos Lineament. It is part of the Interior Basins province of Northeastern Brazil, being related to the fragmentation of the Gondwana supercontinent and the opening of the South Atlantic ocean. The Palestina Graben trends NE-SW and presents an asymmetric geometry, controled by the NW extensional eocretaceous strain. The graben borders display distinct geometries. The SE border is a flexural margin, characterized by the non conformity of the eopaleozoic Mauriti Formation (the oldest unit of the basin) overlying the crystalline basement, but also affected by normal faults with small displacements. On the opposite, the NW border is continuous and rectilinear, being marked by normal faults with major displacements, that control the general tilting of the layers to the NW. In this sense, the Mauriti Formation is overlain by the Brejo Santo, Missão Velha (which also occurs in the Brejo Santo-Mauriti horst, to the NW of the fault border) and Abaiara formations, the latter restricted to the graben. The interpretation of available gravity data and a seismic line indicates that the main fault has a variable dip slip component, defining two deeper portions within the graben, in which the sedimentary column can reach thicknesses of up to 2 km. Regarding to the stratigraphy of Araripe Basin in the study area, the sedimentary package includes three distinct tectonosequences. The Paleozoic Syneclisis Tectonosequence is composed by the Mauriti Formation, deposited by a braided fluvial system. The Jurassic Tectonosequence, whose tectonic setting is still debatable (initial stage of the Neocomian rift, or a pre-rift syneclisis ?), is represented by the Brejo Santo Formation, originated in a distal floodplain related to ephemeral drainages. The Rift Tectonosequence, of neocomian age, includes the Missão Velha Formation, whose lower section is related to a braided to meandering fluvial system, outlining the Rift Initiation Tectonic Systems Tract. The upper section of the Missão Velha Formation is separated from the latter by a major unconformity. This interval was originated by a braided fluvial system, overlain by the Abaiara Formation, a deltaic system fed by a meandering fluvial system. Both sections correspond to the Rift Climax Tectonic Systems Tract. In the area, NE-trending normal to oblique faults are associated with NW transfer faults, while ENE to E-W faults display dominant strike slip kinematics. Both NE and E-W fault sets exhibit clear heritage from the basement structures (in particular, shear zones), which must have been reactivated during the eocretaceous rifting. Faults with EW trends display a dominant sinistral shear sense, commonly found along reactivated segments of the Patos Lineament and satellyte structures. Usually subordinate, dextral directional movements, occur in faults striking NNW to NE. Within this framework bearing to the Palestina Graben, classical models with orthogonal extension or pull-apart style deserve some caution in their application. The Palestina Graben is not limited, in its extremeties, by E-W transcurrent zones (as it should be in the case of the pull-apart geometry), suggesting a model close to the classic style of orthogonal opening. At the same time, others, adjacent depocenters (like the Abaiara-Jenipapeiro semi-graben) display a transtensional style. The control by the basement structures explains such differences

Study of the evolution of the placenta and fetal pancreas in the pathophysiology of growth retardation intrauterine due to restricted maternal diet

CONTEXTO: O retardo do crescimento intra-uterino (RCIU) continua sendo importante problema em perinatologia neste final de século. A natureza do agente etiológico, o período da gestação em que ocorreu o insulto e a sua duração influenciam o tipo de RCIU. OBJETIVO: Estudar a fisiopatologia do retardo de crescimento intrauterino (RCIU) em ratas, decorrente da restrição protéico-calórica materna, em relação à evolução do pâncreas fetal e placenta entre o 18o e 21o dias de prenhez. TIPO DE ESTUDO: Ensaio clínico randomizado em animal de laboratório. PARTICIPANTES: 41 ratas prenhes, normoglicêmicas, da raça Wistar. INTERVENÇÃO: Constituíram-se seis grupos experimentais: controle, com dieta ad libitum e cesárea, respectivamente, no 18º e 21º dias; grupos dieta restritiva a 25% introduzida no 1o dia da prenhez e cesárea no 18o e 21o dias; grupos com a mesma restrição, porém iniciada no 3o dia, com cesárea no 18o e 21o dias. VARIÁVEIS ESTUDADAS: Os recém-nascidos foram classificados, em relação à média mais ou menos um desvio padrão do grupo controle, em peso pequeno (PIP), adequado (AIP) e grande (GIP) para a idade de prenhez; as placentas foram pesadas e processadas para estudo histopatológico, incluindo morfologia e histoquímica, e os pâncreas fetais, para estudo morfológico. RESULTADOS: A desnutrição protéico-calórica materna causou RCIU após o 18o dia da prenhez. Antes desse período não ocorreu RCIU, porque a desnutrição materna diminuiu o número da prole e a placenta tornou-se vicariante. A restrição alimentar não interferiu com a morfologia do pâncreas fetal, e o estudo imunohistoquímico da placenta mostrou que, quando a restrição é introduzida no 1o dia de prenhez, os estoques de glicogênio também não sofrem alterações, diminuindo entre o 18o e 21o dias, como na prenhez normal. A restrição no 3o dia cursou com baixas concentrações de glicogênio placentário no 18o dia e desaparecimento no 21o dia. CONCLUSÃO: A fisiopatologia do RCIU, decorrente da restrição protéico-calórica materna em ratas, está relacionada com menor peso placentário e baixos estoques de glicogênio placentário.

Promotion of hepatocarcinogenesis by hexachlorobenzene in energy-restricted rats

The interaction between dietary energy restriction and low dose of the fungicide hexachlorobenzene (HCB) was evaluated in a rat liver medium-term bioassay for carcinogenesis. Male Wistar rats were fed a control or a 50% energy-restricted diet, both added or not with 50 ppm HCB, for 6 weeks. HCB exposure or energy restriction separately did not exert any influence on the development of glutathione S-transferase placental form (GST-P+) foci of hepatocytes. Simultaneous HCB exposure and energy restriction induced a significant increase in liver centrilobular hypertrophy and GST-P+ foci development. Our findings suggest that energy restriction increases liver response to low dose of HCB, unmasking the promoting potential of this fungicide. (C) 2000 Elsevier B.V. Ireland Ltd. All rights reserved.

Performance, incidence of metabolic disturbances and endocrine variables of food-restricted male broiler chickens

1. This experiment was carried out to evaluate the productive and physiological consequences of a slight but long term food restriction of male broiler chickens from 2 commercial strains.2. Cobb-500 and Ross chickens were submitted to a 20% food restriction from 8 to 21 d of age. Strain, food programme and their interactive effects were analysed in terms of consequences upon performance, mortality, incidence of sudden death syndrome (SDS) and ascites syndrome (AS), index of right cardiac hypertrophy and plasma concentrations of hormones related to metabolism and growth (T-3, T-4, T-3:T-4 ratio, IGF-I and GH).3. Although some catch-up growth was observed by refeeding previously restricted birds after 22 d of rearing, food restriction decreased (P less than or equal to 0.05) body weight at market age (42 d) irrespective of the strain, but improved (P less than or equal to 0.05) food conversion.4. The incidence of mortality was not high in non-restricted birds but SDS and AS caused more than 50% of deaths. Hypertrophic cardiac index was observed in chickens of both strains after 4 weeks of age and was higher in ad libitum fed birds.5. During the period of food restriction, plasma T-3 and IGF-I concentrations decreased whereas plasma T-4 and GH concentrations increased compared to those of the age-matched ad libitum fed counterparts. During the subsequent ad libitum feeding period, few differences in circulating hormone concentrations were observed, except for the higher mean CH litres in previously food-restricted chickens at 35 d of age.6. These results indicate that even a non-severe food restriction negatively affects body weight of 42-d-old male broilers but these are benefits with improved food efficiency and diminished mortality from metabolic disturbances. The hormone results suggest that the degree of food restriction applied was not severe because there was a very fast adaptive response with small and transient alterations in T-3, T-4 and GH plasma concentrations during the period of compensatory growth.

Exercise training increases myocardial inotropic response in food restricted rats

This study evaluated the effects of exercise training on myocardial function and ultrastructure of rats submitted to different levels of food restriction (FR). Male Wistar-Kyoto rats, 60 days old, were submitted to free access to food, light FR (20%), severe FR (50%) and/or to swimming training (one hour per day with 5% of load, five days per week for 90 days). Myocardial function was evaluated by left ventricular papillary muscle under basal condition (calcium 1.25 mM), and after extracellular calcium elevation to 5.2 mM and isoproterenol (I PM) addition. The ultrastructure of the myocardium was examined in the papillary muscle. The training effectiveness was verified by improvement of myocardial metabolic enzyme activities. Both 20% and 50% food restriction protocols presented minor body and ventricular weights gain. The 20%-FR, in sedentary or trained rats, did not alter myocardial function or ultrastructure. The 50%-FR, in sedentary rats, caused myocardial dysfunction under basal condition, decreased response to inotropic stimulation, and promoted myocardial ultrastructural damage. The 50%-FR, in exercised rats, increased myocardial dysfunction under basal condition but increased response to inotropic stimulation although there was myocardial ultrastructural damage. In conclusion, the exercise training in severe restriction caused marked myocardial dysfunction at basal condition but increased myocardial response to inotropic stimulation. (c) 2005 Elsevier B.V.. All rights reserved.

Growth and photosynthetic down-regulation in Coffea arabica in response to restricted root volume

Coffee (Coffea arabica L.) plants were grown in small (3-L), medium (10-L) and large (24-L) pots for 115 or 165 d after transplanting (DAT), which allowed different degrees of root restriction. Effects of altered source : sink ratio were evaluated in order to explore possible stomatal and non-stomatal mechanisms of photosynthetic down-regulation. Increasing root restriction brought about large and general reductions in plant growth associated with a rising root : shoot ratio. Treatments did not affect leaf water potential or leaf nutrient status, with the exception of N content, which dropped significantly with increasing root restriction even though an adequate N supply was available. Photosynthesis was severely reduced when plants were grown in small pots; this was largely associated with non-stomatal factors, such as decreased Rubisco activity. At 165DAT contents of hexose, sucrose, and amino acids decreased in plants grown in smaller pots, while those of starch and hexose-P increased in plants grown in smaller pots. Photosynthetic rates were negatively correlated with the ratio of hexose to free amino acids, but not with hexose content. Activities of acid invertase, sucrose synthase, sucrose-P synthase, fructose-1,6- bisphosphatase, ADP-glucose pyrophosphorylase, starch phosphorylase, glyceraldehyde-3-P dehydrogenase, PPi : fructose-6-P 1-phosphotransferase and NADP : glyceraldehyde-3-P dehydrogenase all decreased with severe root restriction. Glycerate-3-P : Pi and glucose-6-P : fructose-6-P ratios decreased accordingly. Photosynthetic down-regulation was unlikely to have been associated directly with an end-product limitation, but rather with decreases in Rubisco. Such a down-regulation was largely a result of N deficiency caused by growing coffee plants in small pots.

Time-place learning in food-restricted Nile tilapia

Time-place learning based on food association was investigated in eight food-restricted Nile tilapias. Each fish was individually housed for 10 days in an experimental tank for adjustments to laboratory conditions, and fed daily in excess. Feeding was then interrupted for 17 days. Training was then started, based on a food-restricted regime in a tank divided into three interconnected compartments. Daily food was offered in one compartment (left or right side) of the tank in the morning and on the opposite side in the afternoon, for a continuous 30-day period. Frequency of choices on the right side was measured on days 10, 20 and 30 (during these test days, fish were not fed). Following this 30-day conditioning period, the Nile tilapias were able to switch sides at the correct period of the day to get food, suggesting that food restriction facilitates time-place learning discrimination. (C) 2007 Elsevier B.V. All rights reserved.

Messenger ribonucleic acid abundance of intestinal enzymes and transporters in feed-restricted and refed chickens at different ages

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Allozyme differentiation of two populations of the genus Neoplecostomus Eigenmann & Eigenmann, 1888 (Teleostei, Loricariidae) from the upper Paraná River basin, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Survey for Foot-and-mouth Disease in the Endangered Marsh Deer (Blastocerus dichotomus) from Marshlands of the Parana River Basin, Brazil

Habitat fragmentation and diseases have resulted in a decline of the marsh deer (Blastocerus (dichotomus) throughout its South American range. Our objectives were to determine whether marsh deer intended for translocation from a region of the Rio Parana Basin had been infected previously by foot-and-mouth disease virus (FMDV) and whether they were carrying virus We captured marsh deer from June to October 1998 and collected blood from 108 animals and esophageal-pharyngeal fluid from 53 Serum was tested for antibodies against three FMDV serotypes (O, A, and C) by liquid-phase-blocking sandwich enzyme-linked immunosorbent assay (ELISA) Esophageal-pharyngeal fluid was tested for FMDV RNA by reverse transcription polymerase chain reaction (RT-PCR) and inoculation into three successive baby hamster kidney (BHK-21) cell subcultures, followed by RT-PCR of cultures We detected low log(10) titers (range 1 0-1 5) to FM DV subtype A(24) Cruzeiro in 19 of 108 sampled marsh deer, but failed to isolate FMDV or detect FMDV RNA in any samples we conclude that marsh deer from our study site were unlikely to carry FMDV, however, as a preventive measure, the 19 animals with titers for FMDV were not sent to FMDV-free Brazilian states

Biochemical evidence of a possible new species of Neoplecostomus (Teleostei : Loricariidae) from the upper Rio Parana basin, Brazil

Neoplecostomus paranensis Langeam, 1990, from the upper Rio Parana, is the only Neoplecostomus species described in this basin and is distinguished from its congeners by the lack or reduction of the adipose fin. Neoplecostomus specimens with a normal and always present adipose fin were caught in the Rio Corumba, upper Rio Parana basin. In the present study two samples of populations, one from a tributary of Rio Paranapanema (identified as a typical N. paranensis) and the other from the Rio Corumba were compared through allozyme electrophoresis. Six diagnostic loci were found, Acp-A, Adh-A, Est-A, Gpi-A, Ldh-A and Ldh-B. In addition, the locus Gpi-B showed significant differences between allelic frequencies for the two samples. Nei's genetic identity between the populations was 0.731. The expressive genetic divergence together with the presence of an adipose fin show that the sample from the Rio Corumba is distinct from N. paranensis and probably represents a new species. (C) 2003 Published by Elsevier Ltd.

A new Moenkhausia Eigenmann, 1903 (Ostariophysi: Characiformes) from Chapada Diamantina, rio Paraguaçu Basin, Bahia, Northeastern Brazil

Moenkhausia diamantina, nova espécie, é descrita de tributário do rio Paraguaçu, BA, nordeste do Brasil. Esta espécie é distinguida das demais congêneres por caracteres relacionados ao padrão de coloração do corpo, pela presença de escamas na linha mediana pré-dorsal e número de raios da nadadeira anal.

Expression of renin-angiotensin system signalling compounds in maternal protein-restricted rats: effect on renal sodium excretion and blood pressure

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Deep barcode divergence in Brazilian freshwater fishes: the case of the Sao Francisco River basin

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)