Química e sociedade: um projeto brasileiro para o ensino de química por meio de temas CTS

L'objectiu d'aquest article és presentar el model curricular del llibre de text Química i societat que inclou temes CTS. Es presenta la història del projecte adreçat a l'ensenyament secundari i les característiques innovadores d'aquest material didàctic. Un dels seus aspectes innovadors és la discussió de temes sociocientífics. El model curricular del projecte possibilita un tractament més ampli de temes CTS i ha estat adoptat per professors que busquen un ensenyament de la química per a la ciutadania.The aim of the paper is to present the curriculum model in the textbook Chemistry and society, with the inclusion of STS theme. It presents the historical project of the high school textbook and innovative features of the didactic material. One of them is the focus on discussion of the socio-scientific issues. The curriculum model has given more possibilities for a wide approach of the STS theme, and it has been adopted by teachers who have sought a chemistry education for citizenshi

Genome of Herbaspirillum seropedicae Strain SmR1, a Specialized Diazotrophic Endophyte of Tropical Grasses

The molecular mechanisms of plant recognition, colonization, and nutrient exchange between diazotrophic endophytes and plants are scarcely known. Herbaspirillum seropedicae is an endophytic bacterium capable of colonizing intercellular spaces of grasses such as rice and sugar cane. The genome of H. seropedicae strain SmR1 was sequenced and annotated by The Paraná State Genome Programme—GENOPAR. The genome is composed of a circular chromosome of 5,513,887 bp and contains a total of 4,804 genes. The genome sequence revealed that H. seropedicae is a highly versatile microorganism with capacity to metabolize a wide range of carbon and nitrogen sources and with possession of four distinct terminal oxidases. The genome contains a multitude of protein secretion systems, including type I, type II, type III, type V, and type VI secretion systems, and type IV pili, suggesting a high potential to interact with host plants. H. seropedicae is able to synthesize indole acetic acid as reflected by the four IAA biosynthetic pathways present. A gene coding for ACC deaminase, which may be involved in modulating the associated plant ethylene-signaling pathway, is also present. Genes for hemagglutinins/hemolysins/adhesins were found and may play a role in plant cell surface adhesion. These features may endow H. seropedicae with the ability to establish an endophytic life-style in a large number of plant species

The complete genome sequence of Chromobacterium violaceum reveals remarkable and exploitable bacterial adaptability

Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals (i) extensive alternative pathways for energy generation, (ii) ≈500 ORFs for transport-related proteins, (iii) complex and extensive systems for stress adaptation and motility, and (iv) wide-spread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for the detoxification of xenobiotics that may have biotechnological applications

Improvements on ICA mixture models for image pre-processing and segmentation

Today several different unsupervised classification algorithms are commonly used to cluster similar patterns in a data set based only on its statistical properties. Specially in image data applications, self-organizing methods for unsupervised classification have been successfully applied for clustering pixels or group of pixels in order to perform segmentation tasks. The first important contribution of this paper refers to the development of a self-organizing method for data classification, named Enhanced Independent Component Analysis Mixture Model (EICAMM), which was built by proposing some modifications in the Independent Component Analysis Mixture Model (ICAMM). Such improvements were proposed by considering some of the model limitations as well as by analyzing how it should be improved in order to become more efficient. Moreover, a pre-processing methodology was also proposed, which is based on combining the Sparse Code Shrinkage (SCS) for image denoising and the Sobel edge detector. In the experiments of this work, the EICAMM and other self-organizing models were applied for segmenting images in their original and pre-processed versions. A comparative analysis showed satisfactory and competitive image segmentation results obtained by the proposals presented herein. (C) 2008 Published by Elsevier B.V

Integration of virtual pheromones for mapping/exploration of environments by using multiple robots

Abstract-The multiple robot coordination strategies have several advantages when compared to strategies based on a single robot, in terms of flexibility, gain of information and reduction of map building time. In this paper, a local pheromone map integration method is proposed based on the inter-robot observations, considering a method for the environment exploration named the Inverse Ant System-Based Surveillance System strategy (IAS-SS). Simulation results show that the map integration method is efficient, the trials are performed considering a variable number of robots in an indoor environment. Results obtained from several experiments confirm that the integration process is effective and suitable to execute the control of the access to pheromones in a virtual way

Lipid Characterization Of Embryo Zones By Silica Plate Laser Desorption Ionization Mass Spectrometry Imaging (sp-ldi-msi).

Lipid pathways play important biological roles in mammalian embryology, directing early developmental pathways to differentiation. Phospholipids and triglycerides, among others, are the main composing lipids of zona pellucida in several embryo species. Lipid analysis in embryos by mass spectrometry usually requires sample preparation and/or matrix application. This novel approach using silica plate laser desorption/ionization mass spectrometry imaging (SP-LDI-MSI) allows direct single-cell imaging and embryo region discrimination with no matrix coating. Its application is herein described for two- and eight-cell embryos. Lipid biomarkers for blastomere and intact zona pellucida are reported and corroborated by both fragmentation reactions (MS/MS) and images. Results obtained in this work are understood to be of great use for further developments on in vitro bovine fertilization. Since much of the processes can be monitored by characteristic biomarkers, it is now possible to precisely identify cell division errors during early embryo stages, as well as evaluate pre-implantation conditions.80796-10

Evaluation of the hepatotoxicity of Abarema cochliacarpos extracts in mice Mus musculus

Abarema cochliacarpos (Gomes) Barneby & J.W. Grimes, Fabaceae, is a native species of Brazil popularly known as "barbatimão", frequently found along the north coast of the state of Bahia. Local communities make an infusion from its stem bark, which is used to treat several diseases. This study aimed to evaluate the hepatotoxicity of A. cochliacarpos extracts in mice Mus musculus. The bark infusion and hydroalcoholic extract were administered nasogastrically into two groups of eight animals (four male and four female each). After 45 days all mice were killed and the livers were collected for further histological analysis. Hepatic steatosis, congestion of the hepatic vessels and medicinal plantspresence of macrophages and lymphocytes infiltrates in the liver, were observed in both steatosis group of animals, additionally animals that received the stem bark infusion presented an accumulation of pigments. None of the animals belonging to the negative control group showed any of the symptoms described above. In conclusion, the hydroalcoholic extract and infusion of A. cochliacarpos stem bark were proven to cause intoxication in mice. The hepatotoxicity of the infusion was more aggressive in females. Further studies are necessary to isolate compounds responsible for the toxic characteristics of A. cochliacarpos