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Abstract

The aim of this study was to make a comparison between the results obtained by cytologies and by the detection and genotyping of human papillomavirus (HPV) DNA in the screening of cervical cancer. In this study, there were 994 samples used from human females. These were obtained from liquid-based preparations. The samples were analyzed by cytological technique and by the detection of HPV DNA using the PapilloCheck® Test. The HPV was detected in 28% of the samples. Most of the cytology lesions appeared in HPV positive samples and, within these, the most serious injuries occurred mostly in samples with multiple HPV infections. The results indicate that, in general, there is a correlation between the detection of HPV DNA and cytology. However, there were some cases that emphasize the limitations of both diagnosis methods (27% cases with viral HPV DNA positive and normal cytologies and about 2% of cytological lesions detected in samples HPV negatives). It is possible to conclude that none of the two techniques is enough by itself and should be applied together in order to increase the accuracy of cervical cancer screening.

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Abstract  

The thermal behavior of four unusual lignocellulose fibers — namely Caroa, Curaua, Piassava and Sponge gourd — is described. Caroa and Curaua fibers showed a more homogeneous thermal degradation, with a single peak dominating in the DTG curve. Piassava and Sponge gourd showed two separated peaks, revealing the more pronounced amounts of hemicellulose present at these fibers. All four fibers are, however, thermally stable up to temperatures of around 200°C. The activation energies for the thermal degradation of the fibers were similar, except for the Caroa fiber. The lower activation energy associated to this fiber was attributed to its higher hemicellulose to cellulose ratio.

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Abstract  

A simple and efficient method to isolate228Ra from natural thorium oxalate was developed. It consists in the coprecipitation of radium by hydrolysis of saturated solutions of ammonium thoroxalate followed by ion-exchange chromatography on Amberlite IR-120. The final product is carrier-free and pure enough for the preparation of thin sources for alpha and conversion electrons spectrometry. The radium coprecipitation utilized in the first step of this method, could be used to separate thorium from most of its radioactive daughters, decreasing the hazards of manipulation of large quantities of thorium.

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Abstract  

Oxamniquine polymeric prodrug with potential antischistosomal activity was prepared using dextran T-70 as a carrier, which was analysed by 1HNMR, 13C NMR and IR spectroscopy. The formation of the oxamniquine salt was confirmed by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) which showed a different thermal behaviour when compared to the physical mixture.

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Abstract

The effect of several fiber surface treatments upon the dynamic mechanical behavior of piassava fiber-reinforced composites was evaluated. In the light of the experimental results obtained the critical volume fraction for the fibers to effectively perform as reinforcement was established. The results show that all treatments performed (mercerization, acetylation, and mercerization + acetylation) enhance the fiber/matrix adhesion, but some treatments also affect the fiber's integrity. At the elastic region the storage modulus of the composites fabricated with treated fibers was higher than that of the untreated fiber-reinforced composite. However, only the composite manufactured with 10 wt% mercerized fibers showed a statistically significant increase of the storage modulus. Above T g the storage modulus was primarily governed by the volume fraction of fibers. Therefore, raw and treated fiber composites had essentially the same behavior.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Almeida, C. Ramos, A. Marques, A. Silva, M. Freitas, M. Farinha, M. Reis, and A. Marques

Abstract  

The objective of this paper was to assess the air pollution and the main sources of Air Particulate Matter in the Setúbal urban/industrial area, Portugal. PM2.5 and PM2.5–10 were sampled in Nuclepore filters and lichens transplants were exposed during 9 months. The levels of elements in these two matrixes were measured by INAA and PIXE. A large data base was created and source apportionment was performed by using Principal Component Analysis. The results showed that the main sources of fine particles were anthropogenic and were related with traffic and local industry. There was an important contribution of natural sources, mainly for the coarse fraction, associated with the sea and the soil. Lichens characterization and mapping showed that different site-specific characteristics controlled the spatial distribution of different elements. This study showed that biomonitoring is an effective complementary method to traditional sampling systems.

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Abstract  

Harbour activities such as loading, unloading and transport of materials may be an important source of Atmospheric Particulate Matter (APM). Depending on the materials, the type of operation and the meteorological conditions, these activities may have an impact on the levels of APM around harbour areas. The aim of this work was to characterize the emissions of dust providing from operations associated with phosphorite handling in harbours. Phosphorite is a non-detrital sedimentary rock which contains high amounts of phosphate bearing minerals and is used for the production of phosphorous based fertilizers. When handled in harbours frequently cause visual and environment impacts due to its physical and chemical characteristics. The techniques Instrumental Neutron Activation Analysis and Particle Induced X-ray Emission were applied as sensitive analytical tools for the determination of heavy metals and rare earth elements in phosphorite and in the APM sampled in the harbour during the unloading operations. Results showed that manipulation of phosphorite during harbour operations resulted in high emissions of particles, principally from the coarse fraction. These emissions were enriched in rare earth elements and heavy metals and were very affected by the provenience of the phosphorite.

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Thermal study of cyclopalladated complexes of the type [Pd2(dmba)2X2(bpe)]

(X=NO- 3, Cl-, N- 3, NCO-, NCS-; bpe=trans-1,2-bis(4-pyridyl)ethylene)

Journal of Thermal Analysis and Calorimetry
Authors: E. T. de Almeida, A. M. Santana, A. V. G. Netto, Claudia Torres, and A. E. Mauro

The synthesis, characterization and thermal analysis of the novel cyclometallated compounds [Pd2(dmba)2Cl2(μ-bpe)] (1), [Pd2(dmba)2(N3)2(μ-bpe)] (2), [Pd2(dmba)2(NCO)2(μ-bpe)] (3), [Pd2(dmba)2(SCN)2(μ-bpe)] (4), [Pd2(dmba)2(NO3)2(μ-bpe)] (5) (bpe=trans-1,2-bis(4-pyridyl)ethylene; dmba=N,N-dimethylbenzylamine) are described. The thermal stability of [Pd2(dmba)2X2(μ-bpe)] complexes varies in the sequence 1>4>3>2>5. The final residues of the thermal decompositions were characterized as metallic palladium by X-ray powder diffraction.

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Abstract  

The growing concern about air quality in harbours is a result of the high impact of the operations on human health and environment. Harbour activities such loading, unloading and transport of dusty materials are important emission sources of Atmospheric particulate matter (APM). The assessment of these fugitive emissions is a difficult task because they depend on the materials, the type of operation and the meteorological scenarios. The main objectives of this work were (1) to evaluate if the techniques k0-based Instrumental neutron activation analysis (k0-INAA) and Particle induced X-ray emission (PIXE) are suitable techniques to assess fugitive emissions in harbours and (2) to estimate the impact of harbour activities on APM levels and composition. Several experimental campaigns were carried out in a Portuguese harbour, during unloading operations of fertilizer and phosphorite provided from Syria and Morocco. PM2.5 and PM2.5–10 were collected, in polycarbonate filters, by Gent samplers. The techniques k0-INAA and PIXE were applied as sensitive analytical tools to perform a complete chemical characterization of the collected samples. Results showed that manipulation of these materials during harbour operations resulted in high emissions of particles, principally from the coarse fraction. These emissions were very affected by the granulometry and nature of the handled materials. Fertilizer emissions were characterized by high concentration of Ca, P, K, Cr, Br and Zn, whereas phosphorite handling contributed principally for the increase of Ca, P and Cr levels.

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Abstract  

In 2006, elementary schools of inner-city Lisbon, Portugal were given questionnaires to identify respiratory problems. In 1,175 children aged 5–10 years, 27.7% reported rhinitis, 2.5% reported hay fever and 25.9% reported asthma symptoms. April and August were the months with higher incidence of rhinitis, with a considerable difference nonetheless (10.5% and 2.3%, respectively.). The former trends are addressed here by using meteorological data, PM2.5, and its elemental speciation. Mann-Whitney U-tests were applied to the data sets. Significantly higher values were found for humidity, K+, NH4 +, Sb and Zn in April, and for temperature, Cl, Mg2+ and Na+ in August. Commuter and heavy-duty traffic may contribute to rhinitis episodes.

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