973 resultados para Germanías, 1519-1523


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Background. Previous studies from our laboratory have shown that luminal perfusion with arginine vasopressin (AVP) stimulates distal tubule secretory potassium flux (J(K)) via V1 receptors (Am J Physiol 278: F809- F816, 2000). In the present work, we investigate the cell signaling mechanism of this process.Methods. In vivo stationary microperfusion was performed in rat cortical distal tubules and luminal K was measured using double K+ resin/reference microelectrodes.Results. In control conditions, J(K) was 0.71 +/- 0.05 nmol. cm(-2).second(-1); this process was inhibited (14%) by 10(-5) mol/L 8-bromo-cyclic adenosine monophosphate (cAMP), and increased by 35% with 10(-8) mol/L phorbol ester [phorbol 12-myristate 13-acetate (PMA), which activates protein kinase C (PKC)]. During luminal perfusion with 10(-11) mol/L AVP, J(K) increased to 0.88 +/- 0.08 nmol. cm(-2).seconds(-1). In the presence of 10(-11) mol/L AVP, J(K) was not affected by 10(-4) mol/L H89, a blocker of protein kinase A (PKA), but was inhibited (45%) by 10(-5) mol/L staurosporine, an inhibitor of PKC, and by 41% during perfusion with 5 x 10(-5) mol/L of the cell Ca2+ chelator bis (2-aminophenoxy) ethane-tetraacetic acid (BAPTA). In order to study the role of Ca2+-dependent K channels in the luminal hormonal action, the tubules were perfused with 5 mmol/L tetraethylammonium chloride (TEA) or 10(-7) mol/L iberiotoxin, in the presence of AVP, and JK was significantly reduced by both agents. Iberiotoxin reduced AVP-stimulated J(K) by 36.4%, and AVP-independent J(K) (after blocking V1 receptors) by only 16%.Conclusion. The results suggest that the luminal V1-receptor effect of AVP on J(K) was mediated by the phospholipase C (PLC)/ Ca2+/PKC signaling path and not by adenylate cyclase/cAMP/PKA, therefore probably acting on maxi-potassium channels.

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In 1997, the Amazon Basin experienced an exceptionally severe El Nino drought. We assessed effects of this rare event on mortality rates of trees in intact rainforest based on data from permanent plots. Long-term (5- to 13-year) mortality rates averaged only 1.12% per year prior to the drought. During the drought year, annual mortality jumped to 1.91% but abruptly fell back to 1.23% in the year following El Nino. Trees dying during the drought dirt not differ significantly in site or species composition from those that died previously, and there was no detectable effect of soil texture on mortality rates. These results suggest that intact Amazonian rainforests are relatively resistant to severe El Nino events.

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A research about arthropode fauna in laying hen excrement was carried out in a poultry house in the State of São Paulo, from January 2001 to December 2002. The objective was to verify the frequency of Diptera and Coleoptera collected by Berlese funil and flutuation methods, and to show correlation between the collect methods and sazonality possible in the currents seasons. A total of 29,499 insects were collected from seventy five collects, being 16,702 Diptera (six families) and 12,797 Coleoptera (four families). Some arthropodes presented direct relation with the collect method, the seasons of the years and the rainfall precipitation, with significant increase in the number of insects collected in certain periods of the year.

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Colegio Isabel was a project that aimed to "civilize" the indigenous children who lived in the Vale do Araguaia region, Goias Province, to educate national workers and, progressively, incorporate the lands owned by the Indians in the productive process. Colegio Isabel allowed its students a marginal integration in the society, assigning them functions that the so called "civilized" people considered degrading. The egress students lived an ambiguous and marginal life, regarding the original ethnic groups and the adopted society.

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Osseointegration was an innovative treatment in dentistry during the last 3 decades. The success of osseointegration is related to factors such as material biocompatibility, adequate quality of bone tissue that allows implantation, surgical technique, and macrostructure and microstructure of implant. The osseointegrated implants are successfully applied in dental clinic including oral and facial rehabilitations mainly for patients submitted to mutilating surgeries. However, patients submitted to radiation therapy present risks to treatment with implants owing to adverse effects on bone tissue. Nowadays, the literature suggests different therapies to improve the success of osseointegration such as hyperbaric oxygen therapy that aims to prepare bone and adjacent tissues to receive the implant. Therefore, the purpose of this study was to present a literature review concerning indications, contraindications, successes, and difficulties with hyperbaric oxygen therapy associated to maxillofacial implants.

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Pereira, GR, Leporace, G, Chagas, DV, Furtado, LFL, Praxedes, J, and Batista, LA. Influence of hip external rotation on hip adductor and rectus femoris myoelectric activity during a dynamic parallel squat. J Strength Cond Res 24(10): 27492754, 2010-This study sought to compare the myoelectric activity of the hip adductors (HAs) and rectus femoris (RF) when the hip was in a neutral position or externally rotated by 30 degrees or 50 degrees (H0, H30, and H50, respectively) during a parallel squat. Ten healthy subjects performed 10 repetitions of squats in each of the 3 hip positions and the myoelectric activities of the HAs and RF were recorded. The signal was then divided into categories representing concentric (C) and eccentric (E) contractions in the following ranges of motion: 0-30 degrees (C1 and E1), 30-60 degrees (C2 and E2), and 60-90 degrees (C3 and E3) of knee flexion. From those signals, an root mean square (RMS) value for each range of motion in each hip position was obtained. All values were normalized to those obtained during maximum voluntary isometric contraction. We found that HAs showed a significant increase in myoelectric activity during C3 and E3 in the H30 and H50 positions, as compared with H0. Meanwhile, RF activity did not significantly differ between hip positions. Both muscles showed higher activation during 60-90 degrees (C3 and E3) of knee flexion, as compared with 0-30 degrees (C1 and E1) and 30-60 degrees (C2 and E2). The results suggest that if the aim is to increase HA activity despite the low percentage of muscle activation, squats should be performed with 30 degrees of external rotation and at least 90 degrees of knee flexion.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Two fundamental processes usually arise in the production planning of many industries. The first one consists of deciding how many final products of each type have to be produced in each period of a planning horizon, the well-known lot sizing problem. The other process consists of cutting raw materials in stock in order to produce smaller parts used in the assembly of final products, the well-studied cutting stock problem. In this paper the decision variables of these two problems are dependent of each other in order to obtain a global optimum solution. Setups that are typically present in lot sizing problems are relaxed together with integer frequencies of cutting patterns in the cutting problem. Therefore, a large scale linear optimizations problem arises, which is exactly solved by a column generated technique. It is worth noting that this new combined problem still takes the trade-off between storage costs (for final products and the parts) and trim losses (in the cutting process). We present some sets of computational tests, analyzed over three different scenarios. These results show that, by combining the problems and using an exact method, it is possible to obtain significant gains when compared to the usual industrial practice, which solve them in sequence. (C) 2010 The Franklin Institute. Published by Elsevier Ltd. All rights reserved.

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In this study, the occurrence of Othonella araguaiana Mendes, a rare bivalve species is reported for the first time in the Pinzonella illusa biozone, Middle Permian Corumbatai Formation, in the State of São Paulo. This species was originally described in coeval rocks of the Estrada Nova Formation (= Corumbatai) from the Alto Araguaia and Alto Garcas regions, State of Mato Grosso. The specimens of O. araguaiana were found in the base of a bioclastic sandstone bed, a proximal tempestite, in the middle of the Corumbatai Formation, in the city of Rio Claro, São Paulo State. The silicified shells and internal molds are well preserved, showing impressions of muscle scars and other internal anatomic characters (e.g., hinge), never illustrated by previous authors. In his original description, Mendes (1963) called attention to the similarity between O. araguaiana and Terraia aequilateralis, a common veneroid of the Corumbatai Formation. Conversely, Runnegar and Newell (1971) suggested that O. araguaiana belongs to Megadesmidae, being a junior synonym of Plesiocyprinella carinata (the commonest megadesmid of the Passa Dois Group). Our study indicates that O. araguaiana is indeed a megadesmid, but is distinct from the P. carinata. The new occurrence of O. araguaiana demonstrates that a) the paleobiogeographic distribution of this species is wider than previously thought (that it was restricted to the northern part of Parana Basin, Mato Grosso State); b) the molluscan fauna of the Corumbatai Formation (P. illusa biozone) in the State of São Paulo is more diverse and dominated by megadesmids; and c) the composition of the molluscan fauna of the Corumbatai Formation in Alto GarYas, State of Mato Grosso, is essentially the same as that of the P. illusa biozone of the eastern margin of the Parana Basin.

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This is a report about the second occurrence and description of the third specimen of Stratiotosuchus maxhechti (Baurusuchidae, Crocodyliformes) from the Bauru Basin, Upper Cretaceous of southeastern Brazil. The material was found in the typical reddish, fine-grained sandstone from the Adamantina Formation, Bauru Group, Monte Alto County, São Paulo State. These strata are considered to be Campanian-Maastrichtian in age. It is the second skull of Stratiotosuchus maxhechti recovered where the choanal region and the skull-mandible articulation is preserved. The holotype of this species comes from the Adamantina Formation from southwestern São Paulo State, while this new specimen comes from its northern-central region, making possible biocbronological and paleoccological correlations among different geographically distant stratigraphic horizons within the Bauru Basin. The main osteologic contributions from this new specimen are the surangular taking part in the skull/mandible articulation and the presence of a relatively well-preserved choanal region, which are not seen in the holotype, furthering the knowledge of Stratiotosuchus maxhechti. Based on the features of this new specimen, an emended diagnosis is provided.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Some Upper Permian conchostracans from the Rio do Rasto Formation (Parana Basin, South Brazil) have very characteristic recurved growth lines at the dorsal margin. All previously described specimens were classified as Palaeolimnadiopsis subalata (Reed) Raymond. However, a re-analysis of these fossils and of additional recently- collected specimens demonstrated that not all can be included in a single species, nor only in the Family Palaeolimnadiopseidae. According to their shape and the size of the umbo, they are classified into three species. The sub-elliptic carapaces with small anterior umbo are maintained in Palaeolimnadiopsis subalata (Reed, 1929) Raymond, 1946. The sub-circular carapaces with small sub-central umbo correspond to the new species Palaeolimnadiopsis riorastensis. The small size of the umbo is a character of the Family Palaeolimnadiopseidae. The small elliptic valves with large anterior umbo are assigned to the new species Falsisca brasiliensis of the Family Perilimnadiidae, which is characterized by large umbos. Palaeolimnadiopsis has a wide chronostratigraphic distribution, but Falsisca is restricted to the Upper Permian-Lower Triassic of Europe and Asia. This interval is in agreement with the probable Late Permian age of the respective strata of the Rio do Rasto formation. Falsisca was not previously recorded in Gondwana.