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1.
Sci Total Environ ; 862: 160694, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36481154

RESUMO

This work pursues the hydro-geochemical and isotopic characterization of the complex groundwater system of the Gioia Tauro Plain, one of the most important industrialized and agricultural coastal areas of southern Italy. The anthropic pressure exposes the water resources at risk of depletion and quality degradation making the plain groundwater a system of high scientific and social interest. The plain is characterized by a shallow aquifer, mostly recharged by local rains and a deep aquifer apparently less influenced by local precipitation. Both aquifers are mainly Ca-HCO3 waters except for localized sectors where Na-HCO3, Na-Cl and Ca-SO4 waters are present. In deep aquifer, both prolonged interaction with sedimentary rocks, mainly deriving from the erosion of crystalline rocks, and direct cation exchange represent the primary factors controlling the formation of Na-HCO3 waters. Mixing processes between these waters and either connate brine and/or deep thermal waters contribute to the formation of isolated high salinity Na-Cl-rich waters. In shallow aquifer, inputs of N-rich sewage and agriculture-related contaminants, and SOx emissions in proximity of the harbor are responsible of the increasing nitrate and sulphate concentrations, respectively. The Cl/Br and NO3/Cl ratios highlight contamination mainly linked to agricultural activities and contribution of wastewater. Along the northern boundary, the warmest groundwater (Na-Cl[SO4]) were found close to a bend of the main strike-slip fault system, locally favouring the rising of B- and Li-rich deep waters, testifying the influence of geological-structural features on deep water circulation. Despite the high-water demand, a direct marine intrusion is localized in a very restricted area, where we observed an incipient groundwater-seawater mixing (seawater contribution ≤7 %). The qualitative and quantitative conditions of the shallow aquifer still have acceptable levels because of the relatively high recharge inflow. A reliable hydrogeochemical conceptual model, able to explain the compositional variability of the studied waters, is proposed.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Água Subterrânea/química , Água , Itália
2.
Sci Total Environ ; 806(Pt 1): 150345, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34563913

RESUMO

The concept of natural background level (NBL) aims at distinguishing the natural and anthropogenic contributions to concentrations of specific contaminants, as groundwater management and protection tools. This is usually defined as a unique value at a regional scale, even when the hydrogeological and geochemical features of a certain territory are far from homogeneous. The concentration of target contaminants is affected by multiple hydrogeochemical processes. This is the case of arsenic in the Calabria region, where concentrations are definitely variable in groundwater. To overcome the limitation of a traditional approach and to include the intrinsic hydrogeological and geochemical heterogeneity into the definition of the natural contribution to As content in groundwater, an integrated probabilistic approach to the NBL assessment combining aquifer-based preselection criteria and multivariate non-parametric geostatistics was proposed. In detail, different NBL values were selected, based on the aquifer type and/or hydrogeochemical features. Then, these aquifer-based NBL values of arsenic were used in the Probability Kriging method to map the probability of exceedance and to provide contamination risk management tools. This multivariate geostatistical approach that takes advantage of the physico-chemical variables used in the aquifer-based NBL values definition allowed mapping the probability of exceedance of As in a physically-based way. The hydrogeochemical diversity of the study area and all the processes affecting As concentrations in the aquifers have been considered too. As a result, the obtained map was characterized by a short-range and long-range variability due to local hydrogeochemical anomalies and water-rock interaction and/or atmospheric precipitation. By this approach, the NBL exceedance probability maps proved to be less "noisy", because the local hydrogeochemical conditions were filtered, and more capable of pointing out anthropogenic inputs or very anomalous natural contributions, which need to be investigated more in detail and properly managed.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Arsênio/análise , Monitoramento Ambiental , Itália , Probabilidade , Poluentes Químicos da Água/análise
3.
J Environ Manage ; 301: 113796, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34626951

RESUMO

Arsenic (As) is one of the most investigated elements worldwide due to its negative impact on the natural system. Its geochemical behavior depends on several geogenic processes, which can cause hazardous enrichment into natural waters, even in remote areas, far from anthropogenic sources. In this work the arsenic pollution issue has been addressed by studying water-rock interaction processes and applying reaction path modelling as a tool to understand the rock-to-water release of As and the fate of this natural pollutant in crystalline aquifers. In-depth geochemical characterization of several water samples discharging from crystalline aquifers was performed. The obtained data were used to fix the boundary conditions and validate the modelling outcomes. The performed modelling allowed to reconstruct the water-rock interaction processes which occur (i) in shallow and relatively shallow crystalline aquifers in which no As anomalies were observed and (ii) in As-rich areas, coupling reaction path modelling of granite dissolution with adsorption of dissolved As onto precipitating crystalline and amorphous Fe(III)-oxyhydroxides given the widespread presence of these phases in the studied environment. The results of the geochemical modelling are in agreement with the analytical data and reproduce them satisfactorily. The performed geochemical modelling is of high environmental significance because it is a flexible and powerful tool that correctly defines the water-rock interaction processes occurring in crystalline aquifers, providing valuable data to improve the knowledge on As behavior, not only in the study area, but also in similar geological settings worldwide. Therefore, the present research has broad future perspectives in the environmental field.


Assuntos
Arsênio , Poluentes Ambientais , Água Subterrânea , Poluentes Químicos da Água , Arsênio/análise , Monitoramento Ambiental , Compostos Férricos/análise , Poluentes Químicos da Água/análise
4.
Eur J Paediatr Neurol ; 35: 93-99, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34673402

RESUMO

Inborn errors of metabolism (IEM) are genetic disorders due to a defective metabolic pathway. The incidence of each disorder is variable and depends on the respective population. Some disorders such as urea cycle disorders (UCD) and organic acidurias, pose a high risk for a metabolic crisis culminating in a life-threatening event, especially during infections; thus, vaccines may play a crucial role in prevention. However, there are different triggers for decompensations including the notion that vaccines themselves can activate fever and malaise. Additionally, many of the IEM include immunodeficiency, placing the patients at an increased risk for infectious diseases and possibly a weaker response to immunizations. Since metabolic crises and vaccine regimens intersect in the first years of life, the question whether to vaccinate the child occupies parents and medical staff. Many metabolic experts hesitate to vaccinate IEM patients, disregarding the higher risk from the direct infections. In this paper we summarize the published data regarding the safety and recommendations for vaccinations in IEM patients, with reference to the risk for decompensations and to the immunogenic component.


Assuntos
Erros Inatos do Metabolismo , Distúrbios Congênitos do Ciclo da Ureia , Criança , Humanos , Incidência , Erros Inatos do Metabolismo/complicações , Pais , Vacinação
5.
Environ Sci Pollut Res Int ; 20(12): 8848-59, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23744159

RESUMO

Black crusts are recognized to have been, up to now, one of the major deterioration forms affecting the built heritage in urban areas. Their formation is demonstrated to occur mainly on carbonate building materials, whose interaction with an SO2-loaded atmosphere leads to the transformation of calcium carbonate (calcite) into calcium sulfate dihydrate (gypsum) which, together with embedded carbonaceous particles, consequently forms the black crusts on the stone surface. An analytical study was carried out on black crust samples collected from limestone monumental buildings and churches belonging to the European built Heritage, i.e., the Corner Palace in Venice (Italy), the Cathedral of St. Rombouts in Mechelen (Belgium), and the Church of St. Eustache in Paris (France). For a complete characterization of the black crusts, an approach integrating different and complementary techniques was used, including laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), Fourier transform infrared spectroscopy, optical and scanning electron microscopy. In particular, the application of LA-ICP-MS permitted to obtain a complete geochemical characterization in terms of trace elements of the black crusts from the inner parts to the external layers contributing to the identification of the major combustion sources responsible for the deterioration over time of the monuments under study. In addition, the obtained results revealed a relation between the height of sampling and the concentration of heavy metals and proved that the crust composition can be a marker to evaluate the variation of the fuels used over time.


Assuntos
Materiais de Construção/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Oligoelementos/análise , Arquitetura , Bélgica , Carbonato de Cálcio/análise , Sulfato de Cálcio/análise , Cultura , França , Itália , Microscopia Eletrônica de Varredura , Paris , Espectroscopia de Infravermelho com Transformada de Fourier
6.
J Nanosci Nanotechnol ; 11(10): 9196-201, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22400323

RESUMO

Luminescence spectra obtained by electron bombardment of carbon nanotubes bundles show an UV signal centered at about 380 nm. We show that these transitions are extrinsic to nanotubes, in the sense that they are not linked to any carbon compound or structure, but are caused by the residual catalyst material used in the growth process. A possible role of such luminescence attributable to impurities is also discussed. In fact our luminescence measurements, in association with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and X-ray photoelectron spectroscopy (XPS), permit us to assign these spectral bands to Zn and Al oxides. Our conclusions, supported by data in literature, and the comparison with the quantitative results obtained by LA-ICP-MS spectrometry (which detects ppm) allows us to define cathode-luminescence analysis as a good technique to control cleanness and purity of carbon nanotube samples.

7.
Haemophilia ; 15(1): 142-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18976255

RESUMO

Inherited coagulopathies are bleeding disorders, which require treatment for life. Keeping an updated registry on these diseases is crucial for planning care, documenting prevalence of diseases and evaluating effectiveness of resources. We have analysed data from 26 treatment centres on coagulopathies in Brazil. Information included socio-demographic data, diagnosis of coagulopathies, severity of haemophilias A and B, presence and quantification of inhibitors in haemophilia, type of von Willebrand disease (VWD) and infection status for viral diseases. On 1 July 2007, there were 10 982 patients with inherited coagulopathies in Brazil, of which 6881 (62.7%) corresponded to haemophilia A, 1291 (11.7%) to haemophilia B, 2333 (21.2%) to VWD, 258 (2.4%) to other coagulopathies and 219 (2.0%) to undiagnosed bleeding disorders. Haemophilia A and B inhibitors were present in 9.9% and 1.9% of the patients, respectively. Human immunodeficiency virus infection was present is 6.5%, 4.8% and 1% of patients with haemophilia A, B and VWD, respectively. Hepatitis C virus infection was present in 34.9%, 29.7% and 12% of patients with haemophilia A, B and VWD, respectively. Infection by hepatitis B and human T-cell leukemia-lymphoma virus was also reported. This is the first report on the registry of patients with inherited coagulopathies in Brazil, supposed to be the third largest population of patients with haemophilia.


Assuntos
Transtornos Herdados da Coagulação Sanguínea/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos Herdados da Coagulação Sanguínea/complicações , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HTLV-I/complicações , Infecções por HTLV-I/epidemiologia , Hemofilia A/epidemiologia , Hemofilia B/epidemiologia , Vacinas contra Hepatite B/provisão & distribuição , Hepatite B Crônica/complicações , Hepatite B Crônica/epidemiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prevalência , Sistema de Registros , Adulto Jovem , Doenças de von Willebrand/epidemiologia
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