Human case of West Nile neuroinvasive disease in Portugal, 2015.

A case of West Nile virus (WNV) infection was reported in the Algarve region, Portugal, in the first week of September 2015. WNV is known to circulate in Portugal, with occasional reports in horses and birds (2004 to 2011) and very sporadically human cases (in 2004 and in 2010). Here we present the clinical and laboratory aspects related to the first human case of West Nile neuroinvasive disease reported in Portugal.

Metals quantification in e-cigarettes liquids by Total Reflection X-ray Spectrometry.

Electronic cigarettes (e-cig) have gained popularity around the world and its health risks demands more research. This study aims at characterizing e-cig liquids (e-liquids) and its constituents by Total Reflection X-ray Spectrometry (TXRF). The internal standard method was the quantification procedure employed. The spectrometer's performance was evaluated with one certified reference material and spiked samples. It was possible to quantify K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, and Pb in the e-liquids. Concentrations above the limit for potable water were found in 10 out of 38 samples. Principal component analysis was useful for identifying toxic samples. TXRF is a promising technique for e-liquids evaluation due to its simplicity and performance.

Separating selenium species by diffusion in Brazilian bentonite: a mathematical modeling approach.

Bentonite was applied in diffusive studies for selenium, an emerging contaminant. The planar source method was used to determine the apparent and effective diffusion coefficients and assess the mobility of the selenium species. A double Gaussian function described the results. Different diffusion coefficients were associated with different mobilities, and consequently, to the coexistence of two selenium species: selenite and selenate. Apparent diffusion coefficients were higher for selenate, around 10- 10 m2 s- 1, than for selenite, around 10- 12 m2 s- 1. Results from sequential extraction and distribution coefficient justified selenate's greater mobility than selenite. Since the increase in redox potential from 448 to 511 mV may be associated with selenite oxidation in an interconversion process, the diffusion in bentonite demonstrates that applications in geological barriers deserve attention regarding the mobilization of selenium species. Interconversions can mobilize selenium, as reduced species can shift to more oxidized and mobile species, enhancing environmental contamination.

Determination of metal content in industrial powder ink and paint thickness over steel plates using X-Ray Fluorescence.

The Energy Dispersive X-Ray Fluorescence (EDXRF) is a well stablished technique that may be used in quality control of industrial processes. In this study, it was proposed an analysis of a two commercial powder inks widely used in the industry. The goals were to determine the composition of the ink by quantifying its inorganics elements by EDXRF, and check if the amount of toxic elements matches with Restriction of Certain Hazardous Substances (RoHS) and with "Norma Brasileira" (NBR) regulations. Moreover, to build Partial Least Squares Regression (PLSR) models to predict the thickness of the ink layer applied over steel plates using EDXRF data. Evaluating the quantitative results, it was found that some samples presented toxic elements, such as Cr and Pb. The PLSR results ranged from 54 µm to 97 µm with an average relative deviation of 1% compared to the conventional method used for thickness determination (magnetic method). The results show that EDXRF is a reliable alternative technique to determine the metal elements on the powder ink composition. Furthermore, a (PLSR) model can be used to determine the thickness of the ink applied over steel plates.

Characterization of Cu2O/TiO2NTs nanomaterials using EDXRF, XRD and DRS for photocatalytic applications.

TiO2 nanotube arrays (TiO2NTs) were decorated with Cu2O nanoparticles by pulse electrochemical deposition. The Cu2O nanoparticles were uniformly distributed onto TiO2NTs surface and with diameter varying between 50 and 200 nm. The effects of the independent variables on the photocatalytic response were simultaneously assessed by a multivariate statistical design. Energy-Dispersive X-Ray Fluorescence, X-Ray Diffraction, FEG-SEM and Diffuse Reflectance Spectroscopy were employed to Cu2O/TiO2NTs characterization. The Cu2O films obtained on TiO2NTs surface were crystalline. DRS analysis confirmed that the modification of TiO2NTs with Cu2O nanoparticles improved the quantum efficiency of the material. The Cu2O/TiO2NTs photoelectrode shows an intense absorption peak in the visible region decreasing the band gap energy from 3.20eV for TiO2NTs to 2.96 eV for Cu2O/TiO2NTs.

Sorption-desorption of antimony species onto calcined hydrotalcite: Surface structure and control of competitive anions.

Calcined hydrotalcite can be applied to remove anionic contaminants from aqueous systems such as antimony species due to its great anion exchange capacity and high surface area. Hence, this study evaluated antimonite and antimonate sorption-desorption processes onto calcined hydrotalcite in the presence of nitrate, sulfate and phosphate. Sorption and desorption experiments of antimonite and antimonate were carried out in batch equilibrium and the post-sorption solids were analyzed by X-ray fluorescence (EDXRF). Sorption data were better fitted by dual-mode Langmuir-Freundlich model (R2>0.99) and desorption data by Langmuir model. High maximum sorption capacities were found for the calcined hydrotalcite, ranging from 617 to 790meqkg-1. The competing anions strongly affected the antimony sorption. EDXRF analysis and mathematical modelling showed that sulfate and phosphate presented higher effect on antimonite and antimonate sorption, respectively. High values for sorption efficiency (SE=99%) and sorption capacity were attributed to the sorbent small particles and the large surface area. Positive hysteresis indexes and low mobilization factors (MF>3%) suggest very low desorption capacity to antimony species from LDH. These calcined hydrotalcite characteristics are desirable for sorption of antimony species from aqueous solutions.

Sorption and desorption of silver ions by bentonite clays.

Anthropogenic activities have increased the concentration of metal species in the environment. The toxicity of silver ions to aquatic and terrestrial organisms has required monitoring by analytical methods, besides actions to promote its control as pollutant. Sorption and desorption processes are directly related to the mobility and availability of metal ions in the environment. In this context, clay minerals can be used for pre-concentration, removal and recovery of silver ions from aqueous solution. Herein, two bentonite clays (BaVC-1 and SWy-2) were characterised and applied to investigate the sorption and desorption of silver ions. Isotherms were fitted to the dual-mode Langmuir-Freundlich model to qualify and quantify sorption sites and evaluate the mobilisation process. The maximum sorption capacity was 743 and 849 meq kg-1 for BaVC-1 and SWy-2, respectively. Hysteresis index (HI) and mobilisation factor (MF) suggest that the desorption of silver ions in BaVC-1 is about four times more conducive compared to that in SWy-2, although both materials have demonstrated a great potential for Ag+ pre-concentration from aqueous solutions.

Sorption-desorption of selenite and selenate on Mg-Al layered double hydroxide in competition with nitrate, sulfate and phosphate.

Selenate and selenite are considered emerging contaminants and pose a risk to living organisms. Since selenium anion species are at low concentration in aquatic environments, materials for its retention are required to enable monitoring. Herein, hydrotalcite was calcined and characterised to investigate sorption and desorption of selenite and selenate in competition with nitrate, sulfate and phosphate. Sorption experiments were carried out in batch system and desorption by sequential dilution. Selenite and selenate concentration remaining after N desorption steps was determined by mass balance. The isotherms were adjusted to the dual-mode Langmuir-Freundlich model (R2 > 0.99). Maximum sorption capacity ranged from 494 to 563 meq kg-1 for selenite and from 609 to 659 meq kg-1 for selenate. Sulfate and phosphate ions showed greater competitive effect on the sorption of selenate and selenite, respectively. Low mobilization factors and high sorption efficiency (MF<3%; SE ≈ 100%) indicated that calcined hydrotalcite has the wanted characteristics for retention of relevant selenium anion species in aqueous media.

Boutonneuse fever and climate variability.

Researchers have long appreciated the role of climate in vector-borne diseases, including the resurgence of boutonneuse fever (BF). Portugal usually is classified as having temperate Mediterranean climate. In this new century, in analyzing the data from the Meteorology Institute, this pattern has changed and an accentuated variability in climate is being observed. BF (febre escaro nodular) is endemic and high season is from late spring and summer. The brown dog tick Rhipicephalus sanguineus. is the vector and reservoir of Rickettsia conorii complex strains: R. conorii Malish and Israeli spotted fever strain. To assess the influence of climate change in BF seasonality our aim was to compare the human sera samples received at CEVDI-INSA for laboratory diagnosis of MSF for 5 months per year from October to February, ("off-season") from 2000 to 2005. Of 1,299 sera samples in persons with suspected clinical diagnosis of MSF, 45 (3.4%) were considered positive cases and the number of positive cases has doubled in the last 2 years. BF epidemiology clearly appears to be associated with climate change, especially with low precipitation values. Physicians should be aware of increasing off-season BF cases.

[Toscana virus in the Portuguese population: serosurvey and clinical cases]. / Vírus Toscana na população Portuguesa: vigilância sero-epidemiológica e casos clínicos.

Toscana virus (Phlebovirus genus, Bunyaviridae family) is a neurotropic virus which circulates in the Mediterranean Basin. Although Portugal has been the second country where its presence was reported, the existence of this virus in our country has been referred only sporadically, and there is a lack of knowledge regarding the prevalence of antibodies in the population. Thus, the objective of this study was to analyse the prevalence of antibodies anti-Toscana virus in the human population in our country. Sero-epidemiological investigations were performed with indirect immunofluorescence assay (IFA) and enzyme linked immunosorbent assay (ELISA) tests. The study population consisted of a control population (blood donors, n=150), a population considered at risk (n=236) and a population of individuals with symptoms and laboratory diagnostic request for vector-borne viruses. The latter population was divided into two groups: those individuals with neurological symptoms (n=165) and those without neurological symptoms (n=373). We tested sera from a total of 924 individuals. The seroprevalence of IgG antibodies in the control population was 2%. In the population considered at risk, the prevalence was 3.4%. In the population with central nervous system disease, we detected a seroprevalence of 4.2%. For the same type of antibodies and in subjects without central nervous system disease, the prevalence was 1.3%. Five cases of recent infection (3%) were detected in the population with neurological signs. Those infections have been acquired in the districts of Faro, Coimbra, Aveiro and Lisbon. The associated clinical diagnoses were meningitis, meningoencephalitis and rash. The observed seroprevalences were, in general, lower than reported in other endemic countries. Only 5 of the 29 sera which gave positive results by IFA and ELISA were confirmed by plaque reduction neutralization tests with the Italian strain ISS.Phl.3. This can indicate the presence of more than one Toscana virus serotype circulating in Portugal and emphasizes the need for more research about this etiological agent in our country.

Elementary chemical analysis in leaves infected by fumagina by X-Ray fluorescence technique

Energy Dispersion X-Ray Fluorescence Technique (EDXRF) was employed to study the effects of the fumagina disease on the elementary chemical composition of the leaves. The experimental set up consisted of a Mo X-ray tube (Ksubµ = 17.44 keV) with Zr filter and a Si (Li) detector. The measurements were performed with the infected and healthy leaves of citric plants. The elements Ti, Mn, Fe, Cu and Zn were quantified, with an average DL of 69, 12, 8, 4 and 4 µg.g-1 respectively. The obtained concentration for Fe varied from 44 to 192 µg.g-1 in healthy leaves and from 363 to 704 µg.g-1 in infected leaves with fumagina .

Foi empregada a técnica de fluorescência de raios X por dispersão de energia (EDXRF), para estudar os efeitos da doença fumagina na composição química elementar de folhas. O arranjo experimental consistiu de um tubo de raios X com anodo de Mo (Kµ = 17.44 keV) com filtro de Zr e um detector de Si(Li). As medidas foram realizadas com folhas de plantas cítricas infectadas e sadias. Foram quantificados os elementos Ti, Mn, Fe, Cu e Zn, com um limite de detecção médio de 69, 12, 8, 4 e 4 µg.g-1 respectivamente. As concentrações obtidas para o Fe variaram de 44 a 192 µg.g-1 em amostras de folhas sadias e de 363 a 704 µg g-1 para as folhas infectadas com fumagina.