Sdo1p,the yeast orthologue of Shwachman–Bodian–Diamond syndrome protein,binds RNA and interacts with nuclear rRNA‐processing factors

The Shwachman–Bodian–Diamond syndrome protein (SBDS) is a member of a highly conserved protein family of not well understood function, with putative orthologues found in different organisms ranging from Archaea, yeast and plants to vertebrate animals. The yeast orthologue of SBDS, Sdo1p, has been previously identified in association with the 60S ribosomal subunit and is proposed to participate in ribosomal recycling. Here we show that Sdo1p interacts with nucleolar rRNA processing factors and ribosomal proteins, indicating that it might bind the pre‐60S complex and remain associated with it during processing and transport to the cytoplasm. Corroborating the protein interaction data, Sdo1p localizes to the nucleus and cytoplasm and co‐immunoprecipitates precursors of 60S and 40S subunits, as well as the mature rRNAs. Sdo1p binds RNA directly, suggesting that it may associate with the ribosomal subunits also through RNA interaction. Copyright © 2009 John Wiley & Sons, Ltd.     

Study of MIG/MAG welding procedures for application of coatings of Inconel 625 nickel alloy on ASTM A387 Gr.11 structural steel

This work aims to study welding techniques applied to repair of components made of ASTM A387 Gr.11 steel, widely used in the oil and gas industry. Due to the working conditions, it is necessary to use materials having good strength and corrosion resistance. UNS N06625 Ni-based alloy (Inconel 625) was used as the filler metal. The MIG/MAG welding process was used to apply the temper bead welding technique with two layers. The methodology of this study was divided in stages, in the first one, exploratory trials were carried out to define the relevance of the studied control factors. In the second step, hardness and microstructure criteria were applied for defining the best heat input relations for the application of the double-layer technique. The double-layer technique was effective in improving the properties of the microstructure in heat-affected zone coatings, intense grain refinement was found. There was also a reduction in microhardness and hardness measurements. Both used shielding gases (Ar + 25% He and Ar + 4% CO2) have achieved heat input relations with positive deviations. In all these relations the heat input of the second layer is greater than the heat input of the first layer.     

Interaction between proton exchange membrane fuel cells and power converters for AC integration

New aspects about steady-state and transient behaviours are considered in the relationships among the model variables for fuel cell (FC) stacks that are of great interest in the scientific environment. In this way, the most important variables are voltage, current, power, heat from cooling system, membrane temperature and hydrogen pressure. The transient model aims at reproducing FC variations of its internal resistance under distinct current levels. This current effect modifies the time response during load turning on/off conditions. Results from a modified FC model are presented and comparisons with real data are made. Additionally, these results are included in an analysis about the electrical interaction between FCs and converters as a cause of great concern among power electronics designers. As the number of such converters has significantly increased in the last few years, FC generation systems are steadily calling attention for operational problems related to their efficiency, stability and durability when DC/DC converters are connected across its terminals. Therefore design proceedings of a DC/DC converter associated to 'T' filters to avoid fast current transitions caused by converter connection across the FC stack terminals are included. To deliver the energy produced by the FC system to the grid, it is presented, also, an analysis of a DC-AC converter used to improve power quality when the FC is, simultaneously, supplying load and grid.     

Effects of heating on protein quality of soybean flour devoid of Kunitz inhibitor and lectin

The effects of autoclaving on protein quality of soybean flours prepared from a conventional soybean (CSB) and an isoline lacking Kunitz inhibitor and lectin (KFLF) were studied. The heating was efficient in the urease, trypsin inhibitors and lectin inactivation, being 15 min sufficient to reduce more than 90% of these compounds and provide protein solubility over 80%. The results of PER, NPR and weight gain showed that heating equally improved the nutritional quality of both soybean flours, although higher autoclaving time was required for KFLF. No significant improvement was observed on NPU and in vivo digestibility of the diets containing KFLF at any heating time. As these later results were similar to those obtained with diets containing CSB, they show the importance of the heating to improve the nutritional value and show that other components rather than trypsin inhibitors and lectins impair the nutritive value of raw soybean.     

Diagnosis of hypovitaminosis A and nutritional anemia status in the population of Vale do Jequitinhonha, Minas Gerais, Brazil

A survey was carried out with the purpose of evaluating the nutritional status of the population of Jequitinhonha Valley in regard to vitamin A deficiency and iron-deficiency anemia. A Program--"Programa de Combate à Hipovitaminose A e à Anemia Nutricional Ferropriva em Bols?es de Probreza de Minas Gerais"--is being implanted by the Instituto Nacional de Alimentac?o e Nutri?ao (INAN) aiming to the prevention of such deficiencies. A random sample of 2,357 children from the towns: Turmalina, Minas Novas and Capelinha (Vale do Jequitinhonha), Minas Gerais (1,604 living in the urban and 753 in the rural areas) was submitted to an eye examination. Blood was drawn from a random subsample of these children (157 from the urban area and 107 from the rural area), in oder to detect possible nutritional problems. The following results were observed (preschool and school children, respectively): 1. Hemoglobin: 23.9% and 20% of the population in the urban area, 34.6 and 18.2% in the rural area, had low and deficient values, respectively. 2. Hematocrit: 1.5 and 2.2% of the population in the urban area, 17.3 and 5.5% in the rural area, had low values. 3. Vitamin A: 8.9 and 4.4% of the population in the urban area, 5.8 and 0% in the rural area, had deficient values (less than 10 micrograms/dl); 26.9 and 31.1% in the urban area, 26.9 and 23.6% in the rural area, had low values (10-20 micrograms/dl). These results show the occurrence of nutritional anemia and vitamin A deficiency in the observed children. As to the eye examination this was performed in 2,357 children. A high incidence of conjunctival xerosis (3.16 and 6.04% in the urban area, 7.7 and 12.6% in the rural area, in preschool and school children, respectively), was detected. Five cases of conjunctival xerosis with Bitot spot (0.2%), corneal xerosis (0.08%) and kerotomalacia (0.04%) were observed. The therapeutic effect of 200,000 UI of oral vitamin A was more efficient in preschool children (90.3% of positive reactions) than in school children (25.9% of positive reactions). The causes of the different reactions are now under study.