Atmospheric corrosion of reference metals in Antarctic sites

This paper presents the results obtained at three Antarctic test sites participating in the “Ibero-American Map of Atmospheric Corrosiveness” (MICAT), a project on atmospheric corrosion carried out during the period 1988–1994 at some 70 sites distributed across 12 countries of the Latin-American region, Spain and Portugal. The three Antarctic sites are located near the coastline.The singular climatic characteristics of Antarctic regions are related with the purity of the air, the absence of rainfall and the formation of ice on the metallic surface during an important part of the exposure time. However, electrochemical activity is possible below ice layers. This situation affects the structure and morphology of corrosion product films and the resulting corrosion rates of metallic surfaces.     

A new robust algorithmic for multi-camera calibration with a 1D object under general motions without prior knowledge of any camera intrinsic parameter

In computer vision, camera calibration is a necessary process when the retrieval of information such as angles and distances is required. This paper addresses the multi-camera calibration problem with a single dimension calibration pattern under general motions. Currently, the known algorithms for solving this problem are based on the estimation of vanishing points. However, this estimate is very susceptible to noise, making the methods unsuitable for practical applications. Instead, this paper presents a new calibration algorithm, where the cameras are divided into binocular sets. The fundamental matrix of each binocular set is then estimated, allowing to perform a projective calibration of each camera. Then, the calibration is updated for the Euclidean space, ending the process. The calibration is possible without imposing any restrictions on the movement of the pattern and without any prior information about the cameras or motion. Experiments on synthetic and real images validate the new method and show that its accuracy makes it suitable also for practical applications.     

Long-term atmospheric corrosion of mild steel

A great deal of information is available on the atmospheric corrosion of mild steel in the short, mid and even long term, but studies of the structure and morphology of corrosion layers are less abundant and generally deal with those formed in just a few years. The present study assesses the structure and morphology of corrosion product layers formed on mild steel after 13 years of exposure in five Spanish atmospheres of different types: rural, urban, industrial and marine (mild and severe). The corrosion layers have been characterised by X-ray diffraction (XRD) and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Long-term corrosion is seen to be more severe in the industrial and marine atmospheres, and less so in the rural and urban atmospheres. In all cases the corrosion rate is seen to decrease with exposure time, stabilising after the first 4–6 years of exposure. The most relevant aspects to be noted are (a) the great compaction of the rust layers formed in the rural and urban atmospheres, (b) the formation of hematite and ferrihydrite phases (not commonly found) in the industrial and marine atmospheres, respectively and (c) identification of the typical morphological structures of lepidocrocite (sandy crystals and flowery plates), goethite (cotton balls structures) and akaganeite (cotton balls structures and cigar-shaped crystals).     

Selective attention and distractor frequency in naming performance: Comment on Dhooge and Hartsuiker (2010).

E. Dhooge and R. J. Hartsuiker (2010) reported experiments showing that picture naming takes longer with low- than high-frequency distractor words, replicating M. Miozzo and A. Caramazza (2003). In addition, they showed that this distractor-frequency effect disappears when distractors are masked or preexposed. These findings were taken to refute models like WEAVER++ (A. Roelofs, 2003) in which words are selected by competition. However, Dhooge and Hartsuiker do not take into account that according to this model, picture-word interference taps not only into word production but also into attentional processes. Here, the authors indicate that WEAVER++ contains an attentional mechanism that accounts for the distractor-frequency effect (A. Roelofs, 2005). Moreover, the authors demonstrate that the model accounts for the influence of masking and preexposure, and does so in a simpler way than the response exclusion through self-monitoring account advanced by Dhooge and Hartsuiker. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Use of somatostatin analogue scintigraphy in the localization of recurrent medullary thyroid carcinoma

Detection of recurrence of medullary thyroid carcinoma (MTC) remains a diagnostic problem. Increased serum tumour marker levels frequently indicate recurrence while conventional imaging techniques (CIT) are non-diagnostic. In this study, we performed indium-111 octreotide scintigraphy and CIT in a series of 20 patients with MTC presenting with elevated serum tumour markers after surgery. 111In-octreotide whole-body studies detected 15 pathological uptake foci in 11 of the 20 patients studied and CIT detected 17 lesions in 11 of the 20 patients. Ten patients underwent reoperation, five of them with positive 111In-octreotide scintigraphy and CIT and two with positive isotopic exploration and negative CIT. Surgical findings demonstrated that the results of isotopic study and CIT had been false-positive for MTC in one case (sarcoidosis). The six patients with true-positive 111In-octreotide studies had significantly higher basal calcitonin (CT) and carcinoembryonic antigen (CEA) levels than the patients with negative isotopic studies. The expression of somatostatin receptor (SSTR) subtypes by PC-PCR could be investigated in four cases with a positive isotopic study. Among the three cases with a true-positive study, SSTR2, the SSTR subtype that preferentially binds to the somatostatin analogue octreotide, was detected in two, SSTR5 was demonstrated in the three, and SSTR3 was detected in one. No subtype of SSTR was detected in the case with a final diagnosis of sarcoidosis. We conclude that 111In-octreotide has limited sensitivity in detecting recurrence in patients with MTC, although its sensitivity may improve with high serum CT levels. This radionuclide imaging technique should be employed when conventional imaging techniques are negative or inconclusive or when the presence of somatostatin receptors may provide the basis for treatment with somatostatin analogues.     

Corrosion behaviour of highly alloyed stainless steels in mixed chloride and fluoride aqueous solutions

Laboratory weight loss and cyclic potentiodynamic polarization corrosion tests were performed on two types of corrosion resistant alloys, a duplex alloy (ferritic-austenitic stainless steel) and two austenitic stainless steels, in mixtures of chloride (3000, 9000 and 15000 ppm) and fluoride (4800 and 15000 ppm) ions at pH 3. Two temperatures were tested, 60 and 70°C. The electrochemical results indicate that the duplex stainless steel presents high corrosion resistance. Weight loss results show low corrosion rates of the two types of stainless steels after 60 days exposure. Sonic pits-crevices were found under the corrosion crust deposits on the duplex stainless steel.     

Proline Fingerprint in Intrinsically Disordered Proteins

NMR spectroscopy is one of the main techniques used for high‐resolution studies of intrinsically disordered proteins (IDPs), permitting mapping of the structural and dynamic features of all the amino acids constituting the polypeptide at atomic resolution. Only proline residues are less straightforward to characterize because they lack any amide proton, thus rendering them not directly visible in the commonly used 2D ¹H,¹⁵N correlation experiments. However, proline residues are highly abundant in IDPs and can mediate important functions. In this work we present an easy and effective way to obtain fingerprints of proline residues in IDPs at high resolution.     

Synthesis of polyesters as binders for deinkable inks. II. Kinetics and mechanism of polyesterification between o-phthalic anhydride and neopentyl glycol in bulk at 200°C

The kinetics of the polyesterification in bulk at 200°C between o-phthalic anhydride and neopentyl glycol (2,2-dimethyl-1,3-propanediol) in a nonequimolecular ratio and in the absence of an external catalyst was investigated. The formation of the monoester and two dimeric compounds by uncatalyzed heating of o-phthalic anhydride with neopentyl glycol was virtually complete after dissolution of the anhydride. The data were analyzed statistically by a mathematical method due to Fradet and Maréchal for the estimation of the orders of reaction. This statistical adjustment of the data analysis supports the assumption that the kinetics of polyesterification in the absence of both the solvent and catalyst may be fitted to several orders of reaction over all the conversion. At first, our experimental data may be fitted to 3, or , or 2, etc., overall orders. The results establish that the overall kinetic order of the polyesterification depend upon the goodness of the experimental results and cannot be only selected by means of a correlation coefficient. If this last criterium is adopted, the polyesterification at low, medium, as well as at high conversions may be 3 as the most probable one, order one with respect to acid group concentration, and order two with respect to alcoholic group concentration, in agreement with Flory's predictions. A mechanism consistent with the most plausible kinetic results (I_m,n = 0.9990 and m, n = 1, 2) is proposed. It consists of a dimerization of the alcoholic groups followed by an attack of the acid to the dimer. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 2409–2431, 1997     

Buying and distribution of drugs: perceptions of officers of a network of primary health care in the interior of the state of Sao Paulo

The study present analyse the process to buy and distribution of medicaments for the Basic Unit of Health in municipal district of state S?o Paulo. To achieve some general considerations about the National Politic of Medicaments in Brazil, to emphasize feature relative the its structuration in the Unique System of Health.