Inorganic-Organic Nanocomposite Assembly Using Collagen as a Template and Sodium Tripolyphosphate as a Biomimetic Analog of Matrix Phosphoprotein

Nanocomposites created with polycarboxylic acid alone as a stabilization agent for prenucleation clusters-derived amorphous calcium phosphate exhibit nonperiodic apatite deposition. In the present study, we report the use of inorganic polyphosphate as a biomimetic analog of matrix phosphoprotein for directing poly(acrylic acid)-stabilized amorphous nano-precursor phases to assemble into periodic apatite-collagen nanocomposites. The sorption and desorption characteristics of sodium tripolyphosphate to type I collagen were examined. Periodic nanocomposite assembly with collagen as a template was demonstrated with TEM and SEM using a Portland cement-based resin composite and a phosphate-containing simulated body fluid. Apatite was detected within the collagen at 24 h and became more distinct at 48 h, with prenucleation clusters attaching to the collagen fibril surface during the initial infiltration stage. Apatite-collagen nanocomposites at 72 h were heavily mineralized with periodically arranged intrafibrillar apatite platelets. Defect-containing nanocomposites caused by desorption of TPP from collagen fibrils were observed in regions lacking the inorganic phase.

Neoproterozoic tectonic and magmatic episodes in the NW sector of Borborema Province, NE Brazil, during assembly of Western Gondwana

The Medio Coreau domain of NE Brazil is located along the northwest margin of Borborema Province, the western branch of a Brasiliano/Pan-African collisional belt that formed during the assembly of Western Gondwana. The early Paleoproterozoic basement of the Medio Coreau domain is composed of migmatitic gneisses and juvenile granulites, overlain by late Paleoproterozoic and Neoproterozoic rocks intruded by syn- to post-tectonic Brasiliano granitoids. According to integrated structural and geochronological data (U-Pb zircon and monazite ages), the Neoproterozoic tectonic evolution of the Medio Coreau is characterized by low-angle thrusting and transcurrent deformation. U-Pb geochronological data from plutons intruded during this compressional regime indicate the collisional evolution began at approximately 622 Ma and continued until about 591 Ma. The continuation of convergence until approximately 560 Ma resulted in the formation of NE-SW and E-W shear zones within the Borborema Province and adjoining West African provinces. The final stage of the ductile tectonism was characterized by uplift and high-angle fault generation between approximately 560 and 545 Ma. The last tectonic event was an extensional phase, resulting in the formation of the Jaibaras graben and intrusion of post-orogenic granites at around 532 Ma. (c) 2007 Elsevier Ltd. All rights reserved.

Evidence for Neoproterozoic continental arc magmatism in the Santa Quit��ria Batholith of Cear�� 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, Cear�� State, NE Brazil provide important clues pertaining to the nature of convergence between the Borborema Province and the West African-S��o 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 Quit��ria batholith) between ca. 665 and 591 Ma within the central part of Cear�� State. These findings, along with supporting geophysical data, suggest that convergence between the Borborema Province and the West African-S��o 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 Bras��lia Belt farther to the southwest.

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

The Bras��lia belt borders the western margin of the S��o 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 S��o 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 S��o Francisco Craton from the main tectonic domains of the belt: the internal allochthons (Arax�� Group in the ��rax�� and Passos Nappes), the external allochthons (Canastra Group, Serra da Boa Esperan��a Metasedimentary Sequence and Andrel��ndia Group) and the autochthonous or Cratonic Domain (Andrel��ndia 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 Espinha��o rifting of the S��o 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 S��o Francisco Craton; and ages between 0.9 and 1.0Ga related to the rifting event that led to the individualisation of the S��o Francisco paleo-continent and formation of its passive margins. An amphibolite intercalation in the Arax�� 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 Andrel��ndia Group, deposited on the southern margin of the S��o 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 S��o Francisco Craton. They could be located either in the cratonic area, which is mostly covered by the Neoproterozoic epicontinental deposits of the Bambu�� Group, or in the outer paleo-continental margin, buried under the allochthonous units of the Bras��lia 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 S��o Francisco plate and ended with continental collision against the Paran�� block (and Goi��s terrane). Continuing collision led to the exhumation and cooling of the Arax�� and Passos metamorphic nappes, as indicated by monazite ages of ca. 605Ma and mark the final stages of tectonometamorphic activity in the southern Bras��lia belt. Whilst continent-continent collision was proceeding on the western margin of the S��o Francisco Craton along the southern Bras��lia belt, eastward subduction in the East was generating the 634-599Ma Rio Negro magmatic arc which collided with the eastern S��o Francisco margin at 595-560Ma, much later than in the Bras��lia belt. Thus, the tectonic effects of the Ribeira belt reached the southernmost sector of the Bras��lia belt creating a zone of superposition. The thermal front of this event affected the proximal Andrel��ndia 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 Paran�� block and Goi��s terrane with the S��o Francisco Craton along the Bras��lia belt preceded the accretion of the Amazonian craton by 50-100 million years. �� 2003 Elsevier B.V. All rights reserved.

Trait contributions to fish community assembly emerge from trophic interactions in an individual-based model

Community ecology seeks to understand and predict the characteristics of communities that can develop under different environmental conditions, but most theory has been built on analytical models that are limited in the diversity of species traits that can be considered simultaneously. We address that limitation with an individual-based model to simulate assembly of fish communities characterized by life history and trophic interactions with multiple physiological tradeoffs as constraints on species performance. Simulation experiments were carried out to evaluate the distribution of 6 life history and 4 feeding traits along gradients of resource productivity and prey accessibility. These experiments revealed that traits differ greatly in importance for species sorting along the gradients. Body growth rate emerged as a key factor distinguishing community types and defining patterns of community stability and coexistence, followed by egg size and maximum body size. Dominance by fast-growing, relatively large, and fecund species occurred more frequently in cases where functional responses were saturated (i.e. high productivity and/or prey accessibility). Such dominance was associated with large biomass fluctuations and priority effects, which prevented richness from increasing with productivity and may have limited selection on secondary traits, such as spawning strategies and relative size at maturation. Our results illustrate that the distribution of species traits and the consequences for community dynamics are intimately linked and strictly dependent on how the benefits and costs of these traits are balanced across different conditions. �� 2012 Elsevier B.V.

Fast assembly of non-thiolated DNA on gold surface at lower pH

In a typical protocol for attaching DNA to a gold electrode, thiolated DNA is incubated with the electrode at neutral pH overnight. Here we report fast adsorption of non-thiolated DNA oligomers on gold electrodes at acidic pH (i.e., pH ~3.0). The peak-to-peak potential difference and the redox peak currents in typical cyclic voltammetry of [Fe(CN)6]3- are investigated to monitor the attachment. Compared with incubation at neutral pH, the lower pH can significantly promote the adsorption processes, enabling efficient adsorption even in 30min. The adsorption rate is DNA concentration-dependent, while the ionic strength shows no influence. Moreover, the adsorption is base-discriminative, with a preferred order of A>C���G, T, which is attributed to the protonation of A and C at low pH and their higher binding affinity to gold surface. The immobilized DNA is functional and can hybridize with its complementary DNA but not a random DNA. This work is promising to provide a useful time-saving strategy for DNA assembly on gold electrodes, allowing fast fabrication of DNA-based biosensors and devices. �� 2013 Elsevier Inc.

The behavior of brazilian senators: analyzing the exchange of votes inside the fixed committees during the 52nd legislature

Using the method of Social Networks Analysis, we���ll try to see if politicians swap votes between them seeking support for their projects, to this end, we���ll first map the behavior, activities and contacts of the Senators of the Brazilian Federative Republic within all the fixed committees which had some vote during the 52nd Legislature, then we can see the most popular and central Senators to each committee. After this analysis we wish to answer the following question: did logrolling exist in the Brazilian Senate? Previously the empirical analysis and response to the problems posed, we���ll present the necessary theoretical introduction understood by reviewing the literature on relevant subjects, whether they are purely theoretical with respect to the exchange of support, or analytical about the Brazilian political system.

A instala����o do servi��o de inspe����o escolar na Prov��ncia de S��o Paulo (1835-1887)

This article discusses the establishment of the school inspection service in the Province of Sao Paulo between the implementation of the Provincial Legislature in 1835 and the last years of the monarchy. In this work, were taken as sources - the Collection of Laws and Decrees of the Province of S��o Paulo (1835-1889); Speeches of the Presidents of the Province given annually at the opening of the Assembly of S���o Paulo (1835-1889), and the reports of the General Inspectors presented to the President of the Province (1851-1889). To give theoretical support to this analysis, we used the categories of Weberian bureaucratic organization.

Self-assembly in aqueous solution of amphiphilic graft copolymers from oxidized carboxymethylcellulose

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

De novo transcriptome assembly for a non-model species, the blood-sucking bug Triatoma brasiliensis, a vector of Chagas disease

High throughput sequencing (HTS) provides new research opportunities for work on non-model organisms, such as differential expression studies between populations exposed to different environmental conditions. However, such transcriptomic studies first require the production of a reference assembly. The choice of sampling procedure, sequencing strategy and assembly workflow is crucial. To develop a reliable reference transcriptome for Triatoma brasiliensis, the major Chagas disease vector in Northeastern Brazil, different de novo assembly protocols were generated using various datasets and software. Both 454 and Illumina sequencing technologies were applied on RNA extracted from antennae and mouthparts from single or pooled individuals. The 454 library yielded 278 Mb. Fifteen Illumina libraries were constructed and yielded nearly 360 million RNA-seq single reads and 46 million RNA-seq paired-end reads for nearly 45 Gb. For the 454 reads, we used three assemblers, Newbler, CAP3 and/or MIRA and for the Illumina reads, the Trinity assembler. Ten assembly workflows were compared using these programs separately or in combination. To compare the assemblies obtained, quantitative and qualitative criteria were used, including contig length, N50, contig number and the percentage of chimeric contigs. Completeness of the assemblies was estimated using the CEGMA pipeline. The best assembly (57,657 contigs, completeness of 80 %, < 1 % chimeric contigs) was a hybrid assembly leading to recommend the use of (1) a single individual with large representation of biological tissues, (2) merging both long reads and short paired-end Illumina reads, (3) several assemblers in order to combine the specific advantages of each.

Metagenomic assembly and draft genome sequence of an Uncharacterized prevotella sp. from Nelore rumen

Prevotella is one of the most abundant genera in bovine rumen, although no genome has yet been assembled by a metagenomics approach applied to Brazilian Nelore. We report the draft genome sequence of Prevotella sp., comprising 2,971,040��bp, obtained using the Illumina sequencing platform. This genome includes 127 contigs and presents a low 48% GC.