Highly stabilized alpha-NiCo(OH)(2) nanomaterials for high performance device application

Improving the charge capacity, electrochemical reversibility and stability of anode materials are main challenges for the development of Ni-based rechargeable batteries and devices. The combination of cobalt, as additive, and electrode material nanostructuration revealed a very promising approach for this purpose. The new alpha-NiCo mixed hydroxide based electrodes exhibited high specific charge/discharge capacity (355-714 C g(-1)) and outstanding structural stability, withstanding up to 700 redox cycles without any significant phase transformation, as confirmed by cyclic voltammetry, electrochemical quartz crystal microbalance and X-ray diffractometry. In short, the nanostructured alpha-NiCo mixed hydroxide materials possess superior electrochemical properties and stability, being strong candidates for application in high performance batteries and devices. (C) 2012 Elsevier B.V. All rights reserved.

Genetic diversity of the Brazilian Creole cattle Pe-duro assessed by microsatellites and mitochondrial DNA

The objective of this study was to describe the genetic diversity and structure of the largest Pe-duro population by assessing variation at ten autosomal microsatellite (STR) loci and mitochondrial DNA (mtDNA) sequences. The mean expected heterozygosity was 0.755, the mean observed heterozygosity was 0.600 and significant inbreeding coefficient (Fis) and deviations from the Hardy-Weinberg equilibrium in most of analyzed loci demonstrate the impact of inbreeding and homozygosis on this population. A more in-depth genetic analysis could be achieved by expanding the STR list. The analysis of mtDNA provided evidence of ancestral African taurine haplotypes in Pe-duro and excluded maternal Zebuine introgression. In this report, the main Pe-duro population is genetically portrayed by sampling approximately 40% of it. As this herd represents the core of the Pe-duro conservation program, these findings are of outstanding value for the management and preservation of this Brazilian 'native' cattle breed.

Impactos Operacionais das Alterações no Contrato Futuro de Milho da BM&F-Bovespa na Mitigação de Risco

O mercado de milho possui importante participação no cenário agropecuário nacional, pela relevância dentro da indústria de carnes. Destacam-se as estratégias de comercialização do grão, em especial as relacionadas à mitigação do risco de preço com o uso de contratos futuros. Objetiva-se identificar e interpretar os efeitos causados pela modificação no contrato futuro do milho negociado na BM&F-Bovespa, que em setembro de 2008 passou de entrega física para liquidação financeira, sobre o desempenho do mercado futuro do grão comercializado. Avaliam-se a liquidez dos contratos, a volatilidade dos preços futuros e físico do milho, bem como a convergência da base. Identificaram-se como possíveis efeitos da alteração contratual o aumento da liquidez do contrato futuro de milho e a redução da volatilidade dos preços, além da melhoria na convergência da base. Os resultados alinham-se com a teoria e evidenciam impacto positivo da implementação da liquidação financeira no contrato futuro de milho.

Conservative approach to restore the first molar with extensive destruction: a 30-month follow-up

The available options for restoring multiple surface cavities are: amalgam, composite resin, or indirect restorations. Adhesive system and intradentinal pin-retained composite resin restorations should have a similar performance to pin-retained amalgam, regarding resistance to support occlusal forces. Polymerization shrinkage is a major concern when performing direct posterior composite resin restorations and the incremental insertion technique can provide less stress and outstanding margin behavior. Intradentinal pins can potentially enhance composite resin's retention, while reducing gaps caused by polymerization shrinkage. This article reports a clinical case involving an extensive restoration on a posterior tooth with cusp loss that was successfully treated using an intradentinal pin and direct nano-hybrid composite resin restoration.

Quatro Desenhos de Frank Lloyd Wright

O objetivo deste trabalho é discutir aspectos do processo de projeto e sua representação gráfica, num momento em que softwares de projeto 3D vem se tornando hegemônicos na prática do arquiteto e no ensino de arquitetura, em contraponto às práticas de desenho em prancheta. Os motivos e circunstâncias não são objeto do trabalho, cujo foco está numa prática de projeto e representação gráfica 2D, mas que tem muito a contribuir para o debate do quadro acima: os desenhos de projeto de Frank Lloyd Wright. Casos de estudo: quatro pranchas desenhadas por FLLW. É importante notar que, no vasto quadro da historiografia wrightiana, análises e interpretações originais, pioneiras, da arquitetura vem surgindo nas últimas décadas, mas ainda há poucos textos sobre desenhos e representação gráfica do arquiteto. Este constitui uma primeira aproximação do autor acerca de tema que oferece abrangente potencial. São exemplos em que, na relação imagem-objeto, a representação bidimensional constrói o projeto tridimensional. A arquitetura emerge como experimentação sem cair na especulação formal. Demonstram uma prática mais lenta, reflexiva e laboriosa do que a oferecida pelos software 3D atuais – mas onde cada traço, textura e grafismo implica um significado de espaço e materialidade.

Influence of the substitutional solute on the mechanical properties of Ti-Nb binary alloys for biomedical use

Titanium alloys are widely used in the manufacture of biomedical implants because they possess an excellent combination of physical properties and outstanding biocompatibility. Today, the most widely used alloy is Ti-6Al-4V, but some studies have reported adverse effects with the long-term presence of Al and V in the body, without mentioning that the elasticity modulus value of this alloy is far superior to the bone. Thus, there is a need to develop new Ti-based alloys without Al and V that have a lower modulus, greater biocompatibility, and similar mechanical strength. In this paper, we investigated the effect of Nb as a substitutional solute on the mechanical properties of Ti-Nb alloys, prepared in an arc-melting furnace and characterized by density, X-ray diffraction, optical microscopy, hardness and elasticity modulus measurements. The X-ray and microscopy measurements show a predominance of the α phase. The microhardness values showed a tendency to increase with the concentration of niobium in the alloy. Regarding the elasticity modulus, it was observed a nonlinear behavior with respect to the concentration of niobium. This behavior is associated with the presence of the α phase.

Genetic diversity of the Brazilian Creole cattle Pé-duro assessed by microsatellites and mitochondrial DNA

The objective of this study was to describe the genetic diversity and structure of the largest Pé-duro population by assessing variation at ten autosomal microsatellite (STR) loci and mitochondrial DNA (mtDNA) sequences. The mean expected heterozygosity was 0.755, the mean observed heterozygosity was 0.600 and significant inbreeding coefficient (Fis) and deviations from the Hardy-Weinberg equilibrium in most of analyzed loci demonstrate the impact of inbreeding and homozygosis on this population. A more in-depth genetic analysis could be achieved by expanding the STR list. The analysis of mtDNA provided evidence of ancestral African taurine haplotypes in Pé-duro and excluded maternal Zebuine introgression. In this report, the main Pé-duro population is genetically portrayed by sampling approximately 40% of it. As this herd represents the core of the Pé-duro conservation program, these findings are of outstanding value for the management and preservation of this Brazilian 'native' cattle breed.

P2Y1 receptors expressed by C1 neurons determine peripheral chemoreceptor modulation of breathing, sympathetic activity, and blood pressure

Catecholaminergic C1 cells of the rostral ventrolateral medulla (RVLM) are key determinants of the sympathoexcitatory response to peripheral chemoreceptor activation. Overactivation of this reflex is thought to contribute to increased sympathetic activity and hypertension; however, molecular mechanisms linking peripheral chemoreceptor drive to hypertension remain poorly understood. We have recently determined that activation of P2Y1 receptors in the RVLM mimicked effects of peripheral chemoreceptor activation. Therefore, we hypothesize that P2Y1 receptors regulate peripheral chemoreceptor drive in this region. Here, we determine whether P2Y1 receptors are expressed by C1 neurons in the RVLM and contribute to peripheral chemoreceptor control of breathing, sympathetic activity, and blood pressure. We found that injection of a specific P2Y1 receptor agonist (MRS2365) into the RVLM of anesthetized adult rats increased phrenic nerve activity (≈55%), sympathetic nerve activity (38±6%), and blood pressure (23±1 mm Hg), whereas application of a specific P2Y1 receptor antagonist (MRS2179) decreased peripheral chemoreceptor–mediated activation of phrenic nerve activity, sympathetic nerve activity, and blood pressure. To establish that P2Y1 receptors are expressed by C1 cells, we determine in the brain slice preparation using cell-attached recording techniques that cells responsive to MRS2365 are immunoreactive for tyrosine hydroxylase (a marker of C1 cells), and we determine in vivo that C1-lesioned animals do not respond to RVLM injection of MRS2365. These data identify P2Y1 receptors as key determinants of peripheral chemoreceptor regulation of breathing, sympathetic nerve activity, and blood pressure.