Mutagenic Activity of Indigofera truxillensis and I. suffruticosa Aerial Parts

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

Evaluation of WC-10Ni thermal spraying coating by HVOF on the fatigue and corrosion AISI 4340 steel

Shot peening is a surface process widely used to improve the fatigue strength of materials, through compressive residual stresses induced in their surface layers. Considering mechanical components for high responsible applications, wear and corrosion control is currently accomplished by the use of coated materials.In the case of chrome plating or hard anodizing, lower fatigue strength in comparison to uncoated parts are associated to high residual tensile stresses and microcracks density. Under constant or variable amplitude loading microcracks will propagate and cross the interface coating substrate without impediment.The aim of the present study is to analyze the influence of WC-10Ni coating applied by HVOF process on the axial fatigue strength of AISI 4340 steel. The shot peening effect on the fatigue performance of coated AISI 4340 steel was also evaluated. The fractured fatigue specimens were investigated using a scanning electron microscope in order to obtain information about the crack initiation points. (C) 2010 Published by Elsevier Ltd.

Aerial stem and leaf morphoanatomy of some species of Smilax

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

Fermentation and nutritive value of silage and hay made from the aerial part of cassava (Manihot esculenta Crantz)

A mandioca, apesar de ser nativa do Brasil, ainda é sub-utilizada principalmente quando a questão é o aproveitamento da sua parte aérea. Com o objetivo de estudar o potencial da mandioca para alimentação animal, o presente trabalho avaliou as características da parte aérea da planta quando submetida os processos de ensilagem e fenação. Os tratamentos consistiram de: parte aérea ensilada sem emurchecimento (PAS); parte aérea ensilada após 24 horas de emurchecimento (PAE) e parte aérea fenada (PAF). As análises químicas foram realizadas a fim de avaliar os parâmetros que determinam o valor nutritivo da silagem e do feno. O emurchecimento elevou o teor de matéria seca de 25% no material in natura para 27.7%, sem alterar o teor de carboidratos solúveis (33.3 e 35.5% de MS na PAS e PAE respectivamente), bem como o poder tampão (204 mmol kg-1 MS na PAS e 195 mmol kg-1 MS na PAE). Nem o pH (3.57 na silagem in natura e 3.60 na PAE) nem os teores de NIDA (11.32% do nitrogênio total na MS na PAS e 9.99% do nitrogênio total na MS na PAE) diferiram entre as silagens, mas o NIDA foi maior na forragem fenada (15.39%). Contudo, o emurchecimento provocou aumento no nitrogênio amoniacal (de 6.5% do nitrogênio total na MS da PAS para 13.0 do nitrogênio total na MS da PAE). Os teores de ácidos graxos voláteis não sofreram alterações com o emurchecimento. O processo de ensilagem reduziu os teores de ácido cianídrico livre (HCN), sem, contudo, alterar a cianidrina.

Acaricidal activity of ethanolic extract from aerial parts of Tagetes patula L. (Asteraceae) against larvae and engorged adult females of Rhipicephalus sanguineus (Latreille, 1806)

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

Influence of spraying parameters on the electrochemical behaviour of HVOF thermally sprayed stainless steel coatings in 3.4% NaCl

Stainless steel coatings obtained by High Velocity Oxygen Fuel (HVOF) were characterized using optical (OM) and scanning electron microscopy (SEM), electron probe micro-analysis, X-ray diffraction (XRD), open-circuit potential (E-OC) measurements, electrochemical impedance spectroscopy (EIS) and polarisation tests. Differences among coated steels were mainly related with the gun-substrate distance parameter (310 nm for samples A and B and 260 min for C and D). The open-circuit potential values measured for all the samples after 18 h of immersion in aerated and unstirred 3.4% NaCl solution were: - 0.334, - 0.360, - 0.379 and - 0.412 V vs. Ag/AgCl,KClsat. for samples A to D, respectively. For EIS measurements, Nyquist plots showed higher capacitive semi-circle for samples sprayed at longer distance, indicating higher corrosion resistance in NaCl solution. (c) 2005 Elsevier B.V. All rights reserved.

Influência do extrato pirolenhoso na calda de pulverização sobre o teor foliar de nutrientes em limoeiro 'Cravo'

Com o objetivo de avaliar o efeito da presença do extrato pirolenhoso (EP) na calda de pulverização sobre o teor foliar de nutrientes de limoeiro 'Cravo' (Citrus limonia Osbeck), foi desenvolvido um experimento com seis tratamentos e quatro repetições, em blocos ao acaso, em ambiente protegido. Os tratamentos constituíram da pulverização das soluções: T0 = água; T1 = solução de micronutrientes sem EP; T2 = solução de micronutrientes + EP (1cm³ dm-3); T3 = solução de micronutrientes + EP (2 cm³ dm-3); T4 = solução de micronutrientes + EP (5cm³ dm-3); T5 = solução de micronutrientes + EP (10 cm³ dm-3). A solução de micronutrientes foi preparada com sulfatos de Cu, Fe, Mn, Zn (250 mg dm-3 do elemento) e ácido bórico (42,5 mg dm-3 de B). As plantas foram cultivadas em tubetes cônicos de 0,280 dm³, com substrato sem a adição de micronutrientes na formulação. As soluções foram pulverizadas uma única vez, aos 140 dias após o plantio (DAP), momento em que as plantas apresentavam aproximadamente 20 cm de altura. Ao final do experimento (160 DAP), quantificaram-se a massa seca e os teores de macro e micronutrientes da parte aérea e sistema radicular. A presença do extrato pirolenhoso na solução de micronutrientes não interferiu na concentração foliar de B, Fe e Zn em mudas de limoeiro 'Cravo'. Entretanto, na concentração de 10 cm³ dm-3, aumentou a concentração foliar de Cu e Mn. Observou-se também que as plantas pulverizadas com soluções contendo EP (1 a 10 cm³ dm-3) + micronutrientes apresentaram menor teor de Fe e maior teor de Ca no sistema radicular.

PhotoLin: a program to identify and analyze linear structures in aerial photographs, satellite images and maps

A computer program, PhotoLin, written for an IBM-PC-compatible microcomputer is described which detects linear features in aerial photographs, satellite images and topographic maps. The program accepts images saved to PCX files as input and applies noise correction and smoothing filters and thinning routines. The output consists of a skeleton containing the median lines of linear features which can be represented on a map. The branches of the skeleton can be broken into sections of constant length for which the mean orientations are obtained for the preparation of rose diagrams. (C) 2001 Elsevier B.V. Ltd. All rights reserved.

Automatic absolute orientation of scanned aerial photographs

Image orientation is a basic problem in Digital Photogrammetry. While interior and relative orientations were succesfully automated, the same can not be said about absolute orientation. This process can be automated by using an approach based on relational matching and a heuristic that uses the analytical relation between straight features in the object space and its homologous in the image space. A build-in self-diagnosis is also used in this method, that is based on the implementation of data snooping statistic test in the process of spatial resection, using the Iterated Extended Kalman Filtering (IEKF). The aim of this paper is to present the basic principles of the proposed approach and results based on real data.

Iridoids from the aerial parts of Verbena littoralis (Verbenaceae)

The iridoids, 6S-hydroxy-8S-methyl-4-methylene-hexahydro-cyclopenta[c]pyran-3-one and 6S,9S-dihydroxy-8S-methyl-4methylene-hexahydro-cyclopenta[c]pyran-3-one, were isolated from the aerial parts of Verbena littoralis. Their structures and stereochemistry were elucidated by means of NMR spectral data analysis. Both compounds showed moderate in vitro activity against gram positive and negative bacteria as well as moderate in vivo intestinal peristaltic action in mouse. The iridoids also showed moderate free radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) as well as antioxidant activity, the latter being evidenced by redox properties measured using EICD-HPLC. (C) 2004 Elsevier Ltd. All rights reserved.

Pathogenicity of Curtobacterium flaccumfaciens pv. flaccumfaciens to several plant species

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

Dental implants: Surface modification of cp-Ti using plasma spraying and the deposition of hydroxyapatite

The commercial pure titanium (cp-Ti) is currently being used with great success in dental implants. In this work we investigate how the cp-Ti implants can be improved by modifying the metal surface morphology, on which a synthetic material with properties similar to that of the inorganic part of the bone, is deposited to facilitate the bone/implant bonding. This synthetic material is the hydroxyapatite, HA, a calcium-phosphate ceramic. The surface modification consists in the application of a titanium oxide (TiO2) layer, using the thermal aspersion - plasma spray technique, with posterior deposition of HA, using the biomimetic method. The X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray (EDX) and Diffuse Reflectance Infrared Fourier Transform (DRIFT) techniques have been used for characterizing phases, microstructures and morphologies of the coatings. The TiO2 deposit shows a mixture of anatase, rutilo and TiO2-x phases, and a porous and laminar morphology, which facilitate the HA deposition. After the thermal treatment, the previously amorphous structured HA coating, shows a porous homogeneous morphology with particle size of about 2-2.5 μm, with crystallinity and composition similar to that of the biological HA.

Automatic extraction of road seeds from high-resolution aerial images

This article presents an automatic methodology for extraction of road seeds from high-resolution aerial images. The method is based on a set of four road objects and another set of connection rules among road objects. Each road object is a local representation of an approximately straight road fragment and its construction is based on a combination of polygons describing all relevant image edges, according to some rules embodying road knowledge. Each one of the road seeds is composed by a sequence of connected road objects, in which each sequence of this type can be geometrically structured as a chain of contiguous quadrilaterals. Experiments carried out with high-resolution aerial images showed that the proposed methodology is very promising in extracting road seeds. This article presents the fundamentals of the method and the experimental results, as well.