Plasmid-based controls to detect rpoB mutations in Mycobacterium tuberculosis by quantitative polymerase chain reaction-high-resolution melting

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The effect of chain length on the melting temperature and size of dialkyldimethylammonium bromide vesicles

Differential scanning calorimetry (DSc) and dynamic light scattering (DLS) were used to obtain the gel to liquid-crystalline phase transition temperature (T-m) and the apparent hydrodynamic radius (R-h) of spontaneously formed cationic vesicles of dialkyldimethylammonium bromide salts (CnH2n+1)(2)(CH3)(2)N+center dot Br-, with varying chain lengths. The preparation of cationic vesicles from aqueous solution of these surfactants, for n = 12, 14, 16 and 18 (DDAB, DTDAB, DHDAB and DODAB, respectively), requires the knowledge of the surfactant gel to liquid-crystalline phase transition temperature, or melting temperature (T-m) since below this temperature these surfactants are poorly or not soluble in water. That series of cationic surfactants has been widely investigated as vesicle-forming surfactants, although C-12 and C-18, DDAB and DODAB are by far the most investigated from this series. The dependence of T-m of these surfactants on the number n of carbons in the surfactant tails is reported. The T-m obtained by DSC increases non-linearly with n, and the vesicle apparent radius R-h is about the same for DHDAB and DODAB, but much smaller for DDAB. (c) 2006 Elsevier B.V.. All rights reserved.

Statistical Model to DNA Melting

Um modelo estatístico para o DNA é estudado a fim de se obter informações sobre o comportamento de variáveis termodinâmicas. Atenção especial é dada à desnaturação térmica desta macromolécula.

Gross anatomical study of the aortic ARC branches of the paca (Agouti paca, Linnaeus, 1766)

Foi descrita a distribuição do arco aórtico de oito animais da espécie Agouti paca, sendo duas fêmeas adultas e seis filhotes jovens (3 machos e 3 fêmeas) que foram obtidos no Setor de Animais Silvestres da Faculdade de Ciências Agrárias e Veterinárias -- Campus de Jaboticabal. Após morte natural, seus vasos arteriais foram injetados com Neoprene latex 650 (Du Pont do Brasil S.A.) coloridos e colocados em uma solução de formalina a 10%. Depois de dissecados, notou-se que o arco aórtico desses animais emite a artéria subclávia e o tronco braquiocefálico. Este último dá origem à artéria carótida comum esquerda e a um tronco, do qual surgem a artéria carótida comum direita e a artéria subclávia direita. Estas emitem, em cada antímero, a artéria vertebral, a artéria tronco costocervical, a artéria cervical superficial, a artéria axilar e a artéria torácica interna. em apenas um animal a artéria carótida comum esquerda apresenta-se na forma de um sifão, logo após sua origem na artéria subclávia direita. Nos demais animais, a artéria carótida comum esquerda apresenta um trajeto retilíneo.

Mesozoic tectonic evolution of the south Orkney microcontinent, Scotia arc, Antarctica

The South Orkney Islands are the exposed part of a continental fragment on the southern limb of the Scotia are. The islands are to a large extent composed of metapelites and metagreywackes of probable Triassic sedimentary age. Deformation related to an accretionary wedge setting, with associated metamorphism from anchizone to the greenschist facies, are of Jurassic age (176-200 Ma). on Powell Island, in the centre of the archipelago, five phases of deformation are recognized. The first three, associated with the main metamorphism, are tentatively correlated with early Jurassic subduction along the Pacific margin of Gondwana. D-4 is a phase of middle to late Jurassic crustal extension associated with uplift. This extension phase may be related to opening of the Rocas Verdes basin in southern Chile, associated with the breakup of Gondwanaland. Upper Jurassic conglomerates cover the metamorphic rocks unconformably. D-5 is a phase of brittle extensional faulting probably associated with Cenozoic opening of the Powell basin west of the archipelago, and with development of the Scotia are.

Effects of a postweld heat treatment on a submerged arc welded ASTM A537 pressure vessel steel

Postweld heat treatment (PWHT) is frequently applied to steel pressure vessels, following the requirements of the ASME code (section VIII), which establishes the parameters of the PWHT based on the thickness and chemical composition of the welded section. This work shows the results of an analysis undertaken on a sample of ASTM A537 C1 steel subjected to qualifying welding procedure tests including PWHT (650 degreesC/5 h), the results obtained showed that this PWHT practice promoted a reduction in the mechanical properties of the base metal and the heat-affected zone (HAZ).

The Rondonian-San Ignacio Province in the SW Amazonian Craton: An overview

The Rondonian-San Ignacio Province (1.56-1.30 Ga) is a composite orogen created through successive accretion of arcs, ocean basin closure and final oblique microcontinent-continent collision. The effects of the collision are well preserved mostly in the Paragua Terrane (Bolivia and Mato Grosso regions) and in the Alto Guapore Belt and the Rio Negro-Juruena Province (Rondonia region), considering that the province was affected by later collision-related deformation and metamorphism during the Sunsas Orogeny (1.25-1.00 Ga). The Rondonian-San Ignacio Province comprises: (1) the Jauru Terrane (1.78-1.42 Ga) that hosts Paleoproterozoic basement (1.78-1.72 Ga), and the Cachoeirinha (1.56-1.52 Ga) and the Santa Helena (1.48-1.42 Ga) accretionary orogens, both developed in an Andean-type magmatic arc; (2) the Paragua Terrane (1.74-1.32 Ga) that hosts pre-San Ignacio units (>1640 Ma: Chiquitania Gneiss Complex, San Ignacio Schist Group and Lomas Manechis Granulitic Complex) and the Pensamiento Granitoid Complex (1.37-1.34 Ga) developed in an Andean-type magmatic arc; (3) the Rio Alegre Terrane (1.51-1.38 Ga) that includes units generated in a mid-ocean ridge and an intra-oceanic magmatic arc environments; and (4) the Alto Guapore Belt (<1.42-1.34 Ga) that hosts units developed in passive marginal basin and intra-oceanic arc settings. The collisional stage (1.34-1.32 Ga) is characterized by deformation, high-grade metamorphism, and partial melting during the metamorphic peak, which affected primarily the Chiquitania Gneiss Complex and Lomas Manechis Granulitic Complex in the Paragua Terrane, and the Colorado Complex and the Nova Mamore Metamorphic Suite in the Alto Guapore Belt. The Paragua Block is here considered as a crustal fragment probably displaced from its Rio Negro-Juruena crustal counterpart between 1.50 and 1.40 Ga. This period is characterized by extensive A-type and intra-plate granite magmatism represented by the Rio Crespo Intrusive Suite (ca. 1.50 Ga), Santo Antonio Intrusive Suite (1.40-1.36 Ga), and the Teotonio Intrusive Suite (1.38 Ga). Magmatism of these types also occur at the end of the Rondonian-San Ignacio Orogeny, and are represented by the Alto Candeias Intrusive Suite (1.34-1.36 Ga), and the Sao Lourenco-Caripunas Intrusive Suite (1.31-1.30 Ga). The cratonization of the province occurred between 1.30 and 1.25 Ga. (C) 2009 Elsevier Ltd. All rights reserved.

Unbalanced Three-Phase Induction Motors Starting and Arc Welding Machines Short-Circuit Modeling

Three-Phase Induction Motors (TIM) and Arc Welding Machines (AWM) are loads of special behavior widely used in industrial and commercial installations, and therefore may contribute significantly to the deterioration of the quality of energy supplied by utilities. This paper proposes a modeling in constant power of the unbalanced TIM starting using Genetic Algorithm (GA) and AWM short-circuit based on their statics characteristics curves. The proposed models are compared with the conventional models in the literature. The results showed the good performance of the proposed models, allowing a more precise analysis of the real requests of these loads.

Evidence for Neoproterozoic continental arc magmatism in the Santa Quitéria Batholith of Ceará State, NW Borborema Province, NE Brazil: Implications for the assembly of West Gondwana

Recent field investigations and geochronological studies of Neoproterozoic rocks in the northwestern part of the Borborema Province, Ceará State, NE Brazil provide important clues pertaining to the nature of convergence between the Borborema Province and the West African-São Luis craton during the assembly of West Gondwana. U-Pb zircon data indicate that the earliest evidence of convergent magmatism along the northwest margin of the Borborema Province occurred around 777 Ma, and was followed by the development of a large continental arc batholith (Santa Quitéria batholith) between ca. 665 and 591 Ma within the central part of Ceará State. These findings, along with supporting geophysical data, suggest that convergence between the Borborema Province and the West African-São Luis craton involved closure of an oceanic realm with subduction polarity to the southeast beneath the northwestern part of the province. Consequently, it seems likely that the Pharusian Ocean was continuous from the Hoggar Province in West Africa into South America during the late Neoproterozoic and additional data suggests that it may have even been connected with the Goianides Ocean of the Brasília Belt farther to the southwest.

U-Pb geochronology of the southern Brasília belt (SE-Brazil): Sedimentary provenance, Neoproterozoic orogeny and assembly of West Gondwana

The Brasília belt borders the western margin of the São Francisco Craton and records the history of ocean opening and closing related to the formation of West Gondwana. This study reports new U-Pb data from the southern sector of the belt in order to provide temporal limits for the deposition and ages of provenance of sediments accumulated in passive margin successions around the south and southwestern margins of the São Francisco Craton, and date the orogenic events leading to the amalgamation of West Gondwana. Ages of detrital zircons (by ID-TIMS and LA-MC-ICPMS) were obtained from metasedimentary units of the passive margin of the São Francisco Craton from the main tectonic domains of the belt: the internal allochthons (Araxá Group in the Áraxá and Passos Nappes), the external allochthons (Canastra Group, Serra da Boa Esperança Metasedimentary Sequence and Andrelândia Group) and the autochthonous or Cratonic Domain (Andrelândia Group). The patterns of provenance ages for these units are uniform and are characterised as follows: Archean- Paleoproterozoic ages (3.4-3.3, 3.1-2.7, and 2.5-2.4Ga); Paleoproterozoic ages attributed to the Transamazonian event (2.3-1.9Ga, with a peak at ca. 2.15Ga) and to the ca. 1.75Ga Espinhaço rifting of the São Francisco Craton; ages between 1.6 and 1.2Ga, with a peak at 1.3Ga, revealing an unexpected variety of Mesoproterozoic sources, still undetected in the São Francisco Craton; and ages between 0.9 and 1.0Ga related to the rifting event that led to the individualisation of the São Francisco paleo-continent and formation of its passive margins. An amphibolite intercalation in the Araxá Group yields a rutile age of ca. 0.9Ga and documents the occurrence of mafic magmatism coeval with sedimentation in the marginal basin. Detrital zircons from the autochthonous and parautochthonous Andrelândia Group, deposited on the southern margin of the São Francisco Craton, yielded a provenance pattern similar to that of the allochthonous units. This result implies that 1.6-1.2Ga source rocks must be present in the São Francisco Craton. They could be located either in the cratonic area, which is mostly covered by the Neoproterozoic epicontinental deposits of the Bambuí Group, or in the outer paleo-continental margin, buried under the allochthonous units of the Brasília belt. Crustal melting and generation of syntectonic crustal granites and migmatisation at ca. 630Ma mark the orogenic event that started with westward subduction of the São Francisco plate and ended with continental collision against the Paraná block (and Goiás terrane). Continuing collision led to the exhumation and cooling of the Araxá and Passos metamorphic nappes, as indicated by monazite ages of ca. 605Ma and mark the final stages of tectonometamorphic activity in the southern Brasília belt. Whilst continent-continent collision was proceeding on the western margin of the São Francisco Craton along the southern Brasília belt, eastward subduction in the East was generating the 634-599Ma Rio Negro magmatic arc which collided with the eastern São Francisco margin at 595-560Ma, much later than in the Brasília belt. Thus, the tectonic effects of the Ribeira belt reached the southernmost sector of the Brasília belt creating a zone of superposition. The thermal front of this event affected the proximal Andrelândia Group at ca. 588Ma, as indicated by monazite age. The participation of the Amazonian craton in the assembly of western Gondwana occurred at 545-500Ma in the Paraguay belt and ca. 500Ma in the Araguaia belt. This, together with the results presented in this work lead to the conclusion that the collision between the Paraná block and Goiás terrane with the São Francisco Craton along the Brasília belt preceded the accretion of the Amazonian craton by 50-100 million years. © 2003 Elsevier B.V. All rights reserved.

Os granitóides brasilianos da faixa de dobramentos paraguai, MS e MT

The Brazilian Granitic Province from southeastern Mato Grosso do Sul and Mato Grosso region, central western Brazil, can be divided into two major groups and/or magmatic events related to the evolution of the Paraguay Fold Belt. The southern portion crops out in Mato Grosso do Sul State and is constituted by the Taboco, Rio Negro, Coxim and Sonora massifs forming NE-SW oriented, elongated small intrusions. The north portion crops out in Mato Grosso State and is constituted by the São Vicente, Araguaiana and Lajinha batholiths. Lithogeochemical aspects of the northern granites point to Type-I granites ranging from K calc-alkaline to high-K, peraluminous to metaluminous in composition, generated in an environment of continental collision and/or post- collision decompression. The southern granites are Type-I, from K calc-alkaline to high-K, peraluminous to subordinate metalummous, in a syn-collision continental arc environment with the exception of some pre-collisional facies from the Rio Negro Massif. The southern granites have less SiO 2 and K 2O, and are less differentiated and evolved than granites from the northern region. The four southern granites can be grouped into two subordinate sets with the degree of differentiation increasing from South (Taboco and Rio Negro) to North (Coxim and Sonora). The granitic rocks are characterized by a magmatism generated by melting of material from the lower crust which suggests that in this province the formation from non-cogenetic magmas with diversified compositions and distinct degrees of fractioning reaching more steady consolidated environments at the end of the collisional event in the southeastern Amazonian Craton.

In vitro lingual bracket evaluation of indirect bonding with plasma arc, LED and halogen light

Authors - Magno AFF, Martins RP, Vaz LG, Martins LP Objectives - Evaluate the shear bond strength (SBS) and the adhesive remnant index (ARI) of indirect bonded lingual brackets using xenon plasma arc light, light-emitting diode (LED) and conventional quartz-tungsten-halogen light. Material and Methods - Lingual brackets were bonded indirectly to 60 premolars divided to three groups according to the curing light used: Group 1, plasma arc for 6 s; Group 2, LED for 10 s; and Group 3, halogen light for 40 s. After bonding, the specimens were subjected to a shear force until debonding. The debonding pattern was assessed and classified according to the ARI scores. The mean shear bond strengths were accessed by anova followed by the Student-Newman-Keuls test for multiple comparisons. ARI scores were assessed using the chi-square test. Results - The three groups showed significant differences (p < 0.001), with the averages of group 1 < group 2 < group 3. Groups showed no differences regarding ARI scores. Conclusion - Bonding lingual brackets indirectly with plasma arc, during 60% of the time used for the LED, produced lower SBS than obtained with the latter. Using LED during 25% of the time of the halogen light produced lower SBS than obtained with the latter. These differences did not influence the debonding pattern and are clinically acceptable according to the literature. © 2010 John Wiley & Sons A/S.

GRASP with evolutionary path-relinking for the capacitated arc routing problem

The Capacitated Arc Routing Problem (CARP) is a well-known NP-hard combinatorial optimization problem where, given an undirected graph, the objective is to find a minimum cost set of tours servicing a subset of required edges under vehicle capacity constraints. There are numerous applications for the CARP, such as street sweeping, garbage collection, mail delivery, school bus routing, and meter reading. A Greedy Randomized Adaptive Search Procedure (GRASP) with Path-Relinking (PR) is proposed and compared with other successful CARP metaheuristics. Some features of this GRASP with PR are (i) reactive parameter tuning, where the parameter value is stochastically selected biased in favor of those values which historically produced the best solutions in average; (ii) a statistical filter, which discard initial solutions if they are unlikely to improve the incumbent best solution; (iii) infeasible local search, where high-quality solutions, though infeasible, are used to explore the feasible/infeasible boundaries of the solution space; (iv) evolutionary PR, a recent trend where the pool of elite solutions is progressively improved by successive relinking of pairs of elite solutions. Computational tests were conducted using a set of 81 instances, and results reveal that the GRASP is very competitive, achieving the best overall deviation from lower bounds and the highest number of best solutions found. © 2011 Elsevier Ltd. All rights reserved.