Physical analyses of compost from composting plants in Brazil

Nowadays the composting process has shown itself to be an alternative in the treatment of municipal solid wastes by composting plants. However, although more than 50% of the waste generated by the Brazilian population is composed of matter susceptible to organic composting, this process is, still today, insufficiently developed in Brazil, due to low compost quality and lack of investments in the sector. The objective of this work was to use physical analyses to evaluate the quality of the compost produced at 14 operative composting plants in the Sao Paulo State in Brazil. For this purpose, size distribution and total inert content tests were done. The results were analyzed by grouping the plants according to their productive processes: plants with a rotating drum, plants with shredders or mills, and plants without treatment after the sorting conveyor belt. Compost quality was analyzed considering the limits imposed by the Brazilian Legislation and the European standards for inert contents. The size distribution tests showed the influence of the machinery after the sorting conveyer on the granule sizes as well as the inert content, which contributes to the presence of materials that reduce the quality of the final product. (C) 2007 Elsevier Ltd. All rights reserved.

POLYGLYCOLIC ACID TUBE ASSOCIATED WITH GM1 IN REGENERATION OF PERIPHERAL NERVES

Introduction: Nerve allografting is regarded as a treatment of choice in large neural tissue losses preventing repair by primary anastomosis. In these cases, a synthetic polyglycolic acid tube is an alternative for nerve grafting. On the other hand, several studies have emphasized the importance of neurotrophic factors on neural regeneration, including substances with potential to optimize neural regeneration, especially the GM1, an neurotrophic enhancer factor. Objective: to compare, in rats, the neural regeneration degree using histological analysis, regenerated myelinized axons count, and functional analysis with the use of neurotube and GM1. Methods: This assessment was performed by interposing allograft (group A), polyglycolic acid tube (group B) and polyglycolic acid tube associated to GM1 (group C) on 5-mm sciatic nerve defects. Results: Neuroma formation was found only on group A. Groups A and C showed similar histological patterns, except for the regenerated axons on group C, which were shown to be better organized and myelinized than in group A. Conclusion: on functional recovery, no statistically significant difference was found for the three groups, despite of qualitative and quantitative histological differences found.

HiPP: A Novel Hierarchical Point Placement Strategy and its Application to the Exploration of Document Collections

Point placement strategies aim at mapping data points represented in higher dimensions to bi-dimensional spaces and are frequently used to visualize relationships amongst data instances. They have been valuable tools for analysis and exploration of data sets of various kinds. Many conventional techniques, however, do not behave well when the number of dimensions is high, such as in the case of documents collections. Later approaches handle that shortcoming, but may cause too much clutter to allow flexible exploration to take place. In this work we present a novel hierarchical point placement technique that is capable of dealing with these problems. While good grouping and separation of data with high similarity is maintained without increasing computation cost, its hierarchical structure lends itself both to exploration in various levels of detail and to handling data in subsets, improving analysis capability and also allowing manipulation of larger data sets.

Study of environmental burden of lead in children using teeth as bioindicator

The south region of Sao Paulo city hosts the Guarapiranga dam, responsible for water supply to 25% of the city population. Their surroundings have been subject to intense and irregular occupation by people from very low socioeconomics classes. Measurements undertaken on sediment and particulate materials in the dam revealed concentrations of lead. copper, zinc and cadmium above internationally accepted limits. Epidemiological and toxicological studies undertaken by the World Health Organization in individuals exhibiting lead concentrations in blood, near or below the maximum recommended (10 mu g dl(-1)), surprisingly revealed that toxic effects are more intense in individuals belonging to low socioeconomics classes. Motivated by these facts, we aimed at the investigation of chronic incorporation of lead. as well as the use of our BIOKINETICS code, which is based on an accepted ICRP biokinetics model for lead, in order to extrapolate the results from teeth to other organs. The focus of our data taking was children from poor families, living in a small, restrict and allegedly contaminated area in Sao Paulo city. Thus, a total of 74 human teeth were collected. The average concentration of lead in teeth of children 5 to 10 years old was determined by means of a high-resolution inductively coupled plasma mass spectrometer (ICP-MS). For standardization of the measurements, an animal bone certified material (H-Animal Bone), from the International Atomic Energy Agency, was analyzed. The amount of lead in children living in the surroundings of the dam, was approximately 40% higher than those from the control region, and the average lead concentration was equal to 1.3 mu g g(-1) approximately. Grouping the results in terms of gender, tooth type and condition, it was concluded that a carious molar of boys is a much more efficient contamination pathway for lead, resulting in concentrations 70% higher than in the control region. We also inferred the average concentrations of lead in other organs of these children, by making use of our BIOKINETIC code. (C) 2008 Elsevier Ltd. All rights reserved.

The Aedes aegypti larval transcriptome: a comparative perspective with emphasis on trypsins and the domain structure of peritrophins

The genome sequence of Aedes aegypti was recently reported. A significant amount of Expressed Sequence Tags (ESTs) were sequenced to aid in the gene prediction process. In the present work we describe an integrated analysis of the genomic and EST data, focusing on genes with preferential expression in larvae (LG), adults (AG) and in both stages (SG). A total of 913 genes (5.4% of the transcript complement) are LG, including ion transporters and cuticle proteins that are important for ion homeostasis and defense. From a starting set of 245 genes encoding the trypsin domain, we identified 66 putative LG, AG, and SG trypsins by manual curation. Phylogenetic analyses showed that AG trypsins are divergent from their larval counterparts (LG), grouping with blood-induced trypsins from Anopheles gambiae and Simulium vittatum. These results support the hypothesis that blood-feeding arose only once, in the ancestral Culicomorpha. Peritrophins are proteins that interlock chitin fibrils to form the peritrophic membrane (PM) that compartmentalizes the food in the midgut. These proteins are recognized by having chitin-binding domains with 6 conserved Cys and may also present mucin-like domains (regions expected to be highly O-glycosylated). PM may be formed by a ring of cells (type 2, seen in Ae. aegypti larvae and Drosophila melanogaster) or by most midgut cells (type 1, found in Ae. aegypti adult and Tribolium castaneum). LG and D. melanogaster peritrophins have more complex domain structures than AG and T. castaneum peritrophins. Furthermore, mucin-like domains of peritrophins from T. castaneum (feeding on rough food) are lengthier than those of adult Ae. aegypti (blood-feeding). This suggests, for the first time, that type 1 and type 2 PM may have variable molecular architectures determined by different peritrophins and/or ancillary proteins, which may be partly modulated by diet.

A quantum chemical study on a set of non-imidazole H(3) antihistamine molecules

Molecular orbital calculations were carried out on a set of 28 non-imidazole H(3) antihistamine compounds using the Hartree-Fock method in order to investigate the possible relationships between electronic structural properties and binding affinity for H3 receptors (pK(i)). It was observed that the frontier effective-for-reaction molecular orbital (FERMO) energies were better correlated with pK(i) values than highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy values. Exploratory data analysis through hierarchical cluster (HCA) and principal component analysis (PCA) showed a separation of the compounds in two sets, one grouping the molecules with high pK(i) values, the other gathering low pK(i) value compounds. This separation was obtained with the use of the following descriptors: FERMO energies (epsilon(FERMO)), charges derived from the electrostatic potential on the nitrogen atom (N(1)), electronic density indexes for FERMO on the N(1) atom (Sigma((FERMO))c(i)(2)). and electrophilicity (omega`). These electronic descriptors were used to construct a quantitative structure-activity relationship (QSAR) model through the partial least-squares (PLS) method with three principal components. This model generated Q(2) = 0.88 and R(2) = 0.927 values obtained from a training set and external validation of 23 and 5 molecules, respectively. After the analysis of the PLS regression equation and the values for the selected electronic descriptors, it is suggested that high values of FERMO energies and of Sigma((FERMO))c(i)(2), together with low values of electrophilicity and pronounced negative charges on N(1) appear as desirable properties for the conception of new molecules which might have high binding affinity. 2010 Elsevier Inc. All rights reserved.