Effect of B4C, TiB2 and ZrSiO4 ceramic particles on mechanical properties of aluminium matrix composites: Experimental investigation and predictive modelling

This paper focuses on the influence of processing temperature and inclusion of micron-sized B4C, TiB2 and ZrSiO4 on the mechanical performance of aluminium matrix composites fabricated through stir casting. The ceramic/aluminium composite could withstand greater external loads, due to interfacial ceramic/aluminium bonding effect on the movement of grain and twin boundaries. Based on experimental results, the tensile strength and hardness of ceramic reinforced composite are significantly increased. The maximum improvement is achieved through adding ZrSiO4 and TiB2, which has led to 52% and 125% increase in tensile strength and hardness, respectively. To predict the effect of incorporating ceramic reinforcements on the mechanical properties of composites, experimental data of mechanical tests are used to create 3 models named Levenberg-Marquardt Algorithm (LMA) neural networks. The results show that the LMA- neural networks models have a high level of accuracy in the prediction of mechanical properties for ceramic reinforced-aluminium matrix composites.

Working on a Lathe in the Carpentry Department of the New York Trade School

A student or teacher at the New York Trade School is shown working on a lathe in the Carpentry Department. Black and white photograph credited to the New York City Works Progress Administration.

City Of Toronto’S Approach On Implementing The New Federal Wastewater Effluent Regulations Using A GIS-Based Hydrologic And Hydraulic Model

Canada releases over 150 billion litres of untreated and undertreated wastewater into the water environment every year1. To clean up urban wastewater, new Federal Wastewater Systems Effluent Regulations (WSER) on establishing national baseline effluent quality standards that are achievable through secondary wastewater treatment were enacted on July 18, 2012. With respect to the wastewater from the combined sewer overflows (CSO), the Regulations require the municipalities to report the annual quantity and frequency of effluent discharges. The City of Toronto currently has about 300 CSO locations within an area of approximately 16,550 hectares. The total sewer length of the CSO area is about 3,450 km and the number of sewer manholes is about 51,100. A system-wide monitoring of all CSO locations has never been undertaken due to the cost and practicality. Instead, the City has relied on estimation methods and modelling approaches in the past to allow funds that would otherwise be used for monitoring to be applied to the reduction of the impacts of the CSOs. To fulfill the WSER requirements, the City is now undertaking a study in which GIS-based hydrologic and hydraulic modelling is the approach. Results show the usefulness of this for 1) determining the flows contributing to the combined sewer system in the local and trunk sewers for dry weather flow, wet weather flow, and snowmelt conditions; 2) assessing hydraulic grade line and surface water depth in all the local and trunk sewers under heavy rain events; 3) analysis of local and trunk sewer capacities for future growth; and 4) reporting of the annual quantity and frequency of CSOs as per the requirements in the new Regulations. This modelling approach has also allowed funds to be applied toward reducing and ultimately eliminating the adverse impacts of CSOs rather than expending resources on unnecessary and costly monitoring.

The new Brazilian bankruptcy law and its impacts on the credit market

No início de 2005, uma nova Lei de Falências foi aprovada pelo Congresso Nacional, entrando em meados de junho do mesmo ano. A nova legislação ampliou o grau de proteção ao credor em muitos aspectos. Este artigo busca investigar algumas das consequências empíricas dessa nova lei sobre o mercado de crédito, utilizado dados de firmas argentinas, brasileiras, chilenas e mexicanas para estimar dois modelos para dados em painel: o primeiro com tendências específicas para cada firma e o outro com tendência macro comum às firmas de um mesmo país. A estimação dos dois modelos produziu resultados similares. Foram encontrados impactos significativos sobre a oferta de crédito, o custo da dívida e a oferta de crédito segurado, não-segurado e de longo prazo. Não foram encontrados impactos sobre o total de dívida de curto prazo.

Avanços e desafios na gestão municipal do SUS: um retrato das contratações de pessoas e serviços no Estado de São Paulo

O papel dos municípios na garantia da provisão de serviços de saúde no âmbito do Sistema Único de Saúde é crescente, sendo cada vez mais necessário repensar novas formas de financiamento e apoio para fortalecer uma gestão mais eficiente e racional. Esse trabalho vem no sentido de identificar como os municípios estão garantindo essa provisão, dentro de um cenário de restrição orçamentária imposto pelos limites com despesas de pessoal. A metodologia conta com uma primeira abordagem exploratória dos gastos municipais, que revelaram impactos, sendo o principal o aumento das despesas com terceiros após a aprovação da Lei de Responsabilidade Fiscal. A partir dessa análise foi elaborada uma amostra representativa dos municípios do Estado de São Paulo, para detectar como eles conduzem a execução da política de saúde, por meio de entrevistas e de levantamento de informações sobre as formas de contratação de pessoas e serviços no âmbito municipal, ambas recolhidas junto a gestores municipais. Os resultados reforçam a necessidade de investimentos que contemplem as desigualdades intermunicipais e o questionamento no estabelecimento de limites iguais em realidades totalmente desiguais.

Shiitake (lentinula edodes) production on a sterilized bagasse substrate enriched with rice bran and sugarcane molasses

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

Encoding mechanisms based on fast oscillations in the retina of the cat and their dependencies on anesthesia

Processing in the visual system starts in the retina. Its complex network of cells with different properties enables for parallel encoding and transmission of visual information to the lateral geniculate nucleus (LGN) and to the cortex. In the retina, it has been shown that responses are often accompanied by fast synchronous oscillations (30 - 90 Hz) in a stimulus-dependent manner. Studies in the frog, rabbit, cat and monkey, have shown strong oscillatory responses to large stimuli which probably encode global stimulus properties, such as size and continuity (Neuenschwander and Singer, 1996; Ishikane et al., 2005). Moreover, simultaneous recordings from different levels in the visual system have demonstrated that the oscillatory patterning of retinal ganglion cell responses are transmitted to the cortex via the LGN (Castelo-Branco et al., 1998). Overall these results suggest that feedforward synchronous oscillations contribute to visual encoding. In the present study on the LGN of the anesthetized cat, we further investigate the role of retinal oscillations in visual processing by applying complex stimuli, such as natural visual scenes, light spots of varying size and contrast, and flickering checkerboards. This is a necessary step for understanding encoding mechanisms in more naturalistic conditions, as currently most data on retinal oscillations have been limited to simple, flashed and stationary stimuli. Correlation analysis of spiking responses confirmed previous results showing that oscillatory responses in the retina (observed here from the LGN responses) largely depend on the size and stationarity of the stimulus. For natural scenes (gray-level and binary movies) oscillations appeared only for brief moments probably when receptive fields were dominated by large continuous, flat-contrast surfaces. Moreover, oscillatory responses to a circle stimulus could be broken with an annular mask indicating that synchronization arises from relatively local interactions among populations of activated cells in the retina. A surprising finding in this study was that retinal oscillations are highly dependent on halothane anesthesia levels. In the absence of halothane, oscillatory activity vanished independent of the characteristics of the stimuli. The same results were obtained for isoflurane, which has similar pharmacological properties. These new and unexpected findings question whether feedfoward oscillations in the early visual system are simply due to an imbalance between excitation and inhibition in the retinal networks generated by the halogenated anesthetics. Further studies in awake behaving animals are necessary to extend these conclusions

On the Phase Transformation in Mechanically Alloyed Ni-Nb and Ni-Ta and Ni-Nb-Ta Powders

This paper reports on the phase transformation during the preparation of Ni-25Nb, Ni-25Ta, Ni-20Nb-5Ta and Ni-15Nb-10Ta (at-%) powders by high-energy ball milling from elemental powders. The milling process was performed in a planetary ball milling using stainless steel balls and vials, rotary speed of 300rpm, and a ball-to-powder of 10:1. To minimize contamination and spontaneous ignition the powders were handled under argon atmosphere in a glove box. The milled powders were characterized by means of X-ray diffraction techniques. Results indicated that the Ni atoms were preferentially dissolved into the Nb (and/or Ta) lattice at the initial milling times, which contributed to change the relative intensity on the diffraction peaks. After the dissolution of Nb (and/or Ta) into the Ni lattice, the Ni peaks were moved to the direction of lower diffraction angles in Ni-25Nb, Ni-25Ta, Ni-20Nb-5Ta, Ni-15Nb-10Ta powders, indicating that the mechanical alloying was achieved.

Fast-forward/fast-backward substitutions on vector computers

This paper deals with approaches for sparse matrix substitutions using vector processing. Many publications have used the W-matrix method to solve the forward/backward substitutions on vector computer. Recently a different approach has been presented using dependency-based substitution algorithm (DBSA). In this paper the focus is on new algorithms able to explore the sparsity of the vectors. The efficiency is tested using linear systems from power systems with 118, 320, 725 and 1729 buses. The tests were performed on a CRAY Y MP2E/232. The speedups for a fast-forward/fast-backward using a 1729-bus system are near 19 and 14 for real and complex arithmetic operations, respectively. When forward/backward is employed the speedups are about 8 and 6 to perform the same simulations.

Effect of single nucleotide polymorphisms of CAPN1 and CAST genes on meat traits in Nellore beef cattle (Bos indicus) and in their crosses with Bos taurus

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

Effects of dietary trace mineral sources and levels fed to layers in their second laying cycle on the quality of eggs stored at different temperatures and for different periods

This study aimed at evaluating the effects of trace mineral levels and sources supplemented to diets fed to semi-heavy layers in their second laying cycle on the quality of eggs stored for 14 days at different temperatures. The experimental diets consisted of the inclusion of inorganic trace minerals (T1 - control: 100% ITM) and five supplementation levels of organic trace minerals (carboaminophopho chelates) (110, 100, 90, 80, and 70% OTM). Trace mineral inclusion levels (mg/kg feed) were: T1: control - 100% ITM: Zn (54), Fe (54), Mn (72), Cu (10), I (0.61) Se (0.3); T2 - 110% OTM: Zn (59.4), Fe (59.4), Mn (79.2), Cu (11.88), I (1.21) Se (0.59); T3 - 100%: OTM: Zn (54), Fe (54), Mn (72), Cu (10.8), I (1.10) Se (0.54); T4 - 90% OTM: Zn (48.6), Fe (48.6), Mn (64.8), Cu (9.72), I (0.99) Se (0.49); T5 - 80% OTM: Zn (43.2), Fe (43.2), Mn (57.6), Cu (8.64), I (0.88), Se (0.43); T6 - 70% OTM: Zn (37.8), Fe (37.8), Mn (50.4), Cu (7.56), I (0.77) Se (0.38). A completely randomized experimental design in a split-plot arrangement with 60 treatments of four replicates each was applied. The combination of six diets versus storage temperature (room or under refrigeration) was randomized in plots, whereas the sub-plots consisted of storage times (0, 3, 7, 10, and 14 days). Data were submitted to analysis of variance of a model in slip-plots in time using the software package SAS (2000) at 5% probability level. It was concluded that 70% OTM supplementation can be used with no damage to egg quality, independently from storage temperature or time. The quality of refrigerated eggs stored up to 14 days is better than those stored at room temperature.

Effects of intravenous glucose infusion and nutritional balance on serum concentrations of nonesterified fatty acids, glucose, insulin, and progesterone in nonlactating dairy cows

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