Influencia de la Laguna de Aveiro en los contenidos de metales pesados en la plataforma continental adyacente (Portugal)

A chemical analysis of Al, Ca, Fe, Mg, Cu, Pb, Zn, Cr, Co, Ni and Cd was carried out in 22 surface sediment samples of the continental shelf and upper slope between Espinho and Aveiro (Portugal). To reduce the disturbing effects of grain size, all samples were size-normalized by wet sieving (<63 µm). The fine fraction was digested with concentrated acids and analyzed by flame atomic absorption spectrometry. The Al and heavy metal concentrations displayed a similar distribution pattern, decreasing seaward. Exceptions to this general pattern are Ca, Mg and Pb distributions. The Ca contents are related to carbonated biogenic particles that are very abundant in the outer shelf. Multivariate statistical analysis was applied to all data to assess the behaviour and sources of each element analyzed. The results from factor analysis showed that terrigenous supply (from Aveiro Lagoon flow, coastal erosion and littoral drift), grain size (clay) sorting and anthropogenic influences from Aveiro Lagoon are the major factors controlling spatial variations of chemical elements in the continental shelf between Espinho and Aveiro. Unusually high contents of Pb were found in the middle shelf off Furadouro, but we could not determine the possible source of this contamination.Se realizaron análisis químicos de Al, Ca, Fe, Mg, Pb, Zn, Cr, Co, Ni y Cd en 22 muestras de sedimento superficial de la plataforma y vertiente continental entre Espinho y Aveiro (Portugal). Para reducir el efecto de la granulometría del sedimento, se normalizó el tamaño de las muestras mediante tamizado (<63 µm). Se procedió a la digestión de la fracción fina con ácidos concentrados y se analizó mediante espectrometría de absorción atómica con llama. Las concentraciones de Al y metales pesados muestran un patrón de distribución similar, disminuyendo hacia la vertiente. Las excepciones a este patrón general son las distribuciones de Ca, Mg y Pb. El contenido de Ca está relacionado con las partículas biogénicas carbonatadas que son muy abundantes en la plataforma externa. Con el objetivo de determinar el comportamiento y el origen de cada uno de los elementos analizados, se aplicaron técnicas de análisis estadístico multivariante. Los resultados obtenidos muestran que los principales factores que controlan las variaciones espaciales de los elementos químicos en la plataforma continental entre Espinho y Aveiro son los sedimentos terrígenos procedentes de la Laguna de Aveiro, de la erosión costera y de la deriva litoral; el tamaño de grano (tamaño arcillas); y la influencia antropogénica en la Laguna de Aveiro. En la plataforma media, a la altura de Furadouro, se encontraron valores elevados de Pb, aunque no hemos podido determinar la posible fuente de esta contaminación

Caracterización química y mineral ógica de los sedimentos de los canales de Mira, Ílhavo y Ovar de la Laguna de Aveiro (Portugal)

The paleoenvironmental reconstruction of Aveiro Lagoon is being carried out based on the sedimentological, paleoecological, geochemical and mineralogical characterization of sediment samples collected systematically in the lagoon. This paper presents results concerning the changes in the chemical and mineralogical composition of the fine fraction (<63 μm) and the clay fraction (<2 μm) in sediment samples from Aveiro Lagoon, mainly collected from the lower intertidal plain and subtidal deposits located along the Mira, Ílhavo and Ovar channels. A zonography of the lagoon was established based on the parameters analyzed. The results show that the surface and near-surface sediments of Aveiro Lagoon trap relatively large quantities of trace metals, such as Cu, Pb, Co, Ni, Cd, Zn, Fe, Mn and Cr, considered to be partially adsorbed, particularly on silty and clayey particles, and co-precipitated on Fe and Mn oxyhydroxide forms precipitated in the topmost layers of sediments. Series of statistically significant relationships were established between trace metal concentrations and clay content and semi-quantitatively determined clay mineral species in the sediments.La reconstrucción paleoambiental de la Laguna de Aveiro se está realizando mediante la caracterización sedimentológica, paleoecológica, geoquímica y mineralógica de muestras de sedimento recogidas sistemáticamente en la misma. Este artículo presenta resultados relativos a las variaciones en la composición química y mineralógica de las fracciones fina (<63 μm) y arcillosa (<2 μm) de las muestras de sedimento de la Laguna de Aveiro, recogidas principalmente en las planicies intermareales bajas y depósitos submareales de los canales de Mira, Ílhavo y Ovar. Estos parámetros fueron utilizados para caracterizar los sedimentos de cada uno de los canales estudiados de la Laguna de Aveiro. Los sedimentos superficiales y subsuperficiales de esta laguna retienen cantidades relativamente elevadas de elementos vestigiales como Cu, Pb, Co, Ni, Cd, Zn, Fe, Mn y Cr, los cuales se consideran principalmente adsorbidos en partículas fangosas y arcillosas y en óxidos de Fe y Mn. Con base en los parámetros analizados se puede establecer una zonografía de la laguna. Se han encontrado relaciones entre las concentraciones de elementos vestigiales y el contenido de arcilla y las especies minerales de las arcillas en los sedimentos

A Dimensional Reduction Algorithm and Software for Acyclically Dependent Constraints

For discrete equations of motion with acyclic equality constraints and within the context of the null-space method, an original Algorithm is introduced. By first permuting and then topologically ordering the degrees-of-freedom in the constraint gradient matrix, the saddle point problem can be solved with a sparse triangular system for the constraint equations. In this work, we show that saddle problems resulting from constrained (nonlinear) mechanical problems can always be set in this form, with constraint pivots being selected a priori. Given n discrete motion equations and m equality constraints, the original square sparse (n+m)2 ( n + m ) 2 system is replaced by a sparse system (n−m)2 ( n − m ) 2 and a sparse triangular solve with m2 coefficients and n – m right-hand sides. This triangular solve, which involves three sparse matrices (in existing literature only two of the three matrices are sparse), is here discussed in detail. Seven sparse operations are addressed (five standard and two nonstandard) in addition to some specific ad-hoc operations. Algorithms, source code and examples are presented in this work

Influence of Aveiro Lagoon heavy metal contents in the adjacent continental shelf (Portugal)

A chemical analysis of Al, Ca, Fe, Mg, Cu, Pb, Zn, Cr, Co, Ni and Cd was carried out in 22 surface sediment samples of the continental shelf and upper slope between Espinho and Aveiro (Portugal). To reduce the disturbing effects of grain size, all samples were size-normalized by wet sieving (< 63 mu m). The fine fraction was digested with concentrated acids and analyzed by flame atomic absorption spectrometry. The Al and heavy metal concentrations displayed a similar distribution pattern, decreasing seaward. Exceptions to this general pattern are Ca, Mg and Pb distributions. The Ca contents are related to carbonated biogenic particles that are very abundant in the outer shelf. Multivariate statistical analysis was applied to all data to assess the behaviour and sources of each element analyzed. The results from factor analysis showed that terrigenous supply (from Aveiro Lagoon flow, coastal erosion and littoral drift), grain size (clay) sorting and anthropogenic influences from Aveiro Lagoon are the major factors controlling spatial variations of chemical elements in the continental shelf between Espinho and Aveiro. Unusually high contents of Pb were found in the middle shelf off Furadouro, but we could not determine the possible source of this contamination.info:eu-repo/semantics/publishedVersio

Overhydration prevalence in peritoneal dialysis - A 2 year longitudinal analysis

Hypervolemia is a major concern in dialysis patients, and is associated with increased cardiovascular risk and death. Cross sectional analysis have previously demonstrated that peritoneal dialysis (PD) patients are not more overhydrated when compared to haemodialysiś ones. This study was designed to evaluate longitudinal trends in hydration status and corporal composition in a PD population.Pedro Ventura Aguiar, by Abbott laboratory for conferences presentation

Geochemical beach sediments studies: a contribution to a standard definition useful for public health

The purpose of this work is to define a regional background for the elements quantified to identified local anthropogenic contamination, particulary the contribution of Porto and Aveiro urban areas, and highlight the quality of beach and dune sediments. The results of geochemical analysis point to higher concentration of heavy metals (e.g. Pb, Co, Cr and Ni) than the concentration registered in the area used to define the geochemical background and in current sediments from the continental areas that drained to the coastal sector studied. The higher heavy metals content point to urban contaminations and put the focus in the future on the importance of coupling geochemical of sediments and standard water micro-biological studies to reach environmental quality standards required to obtain the European Blue Flag

From Light Chain Deposition to Multiple Myeloma - Case Report and Literature Review

Monoclonal gammopathies consist of a broad spectrum of diseases, ranging from asymptomatic monoclonal gammopathy of undetermined significance to multiple myeloma (MM). Multiple myeloma is a malignant plasma cell disorder and accounts for 10% of all hematological malignancies and 1% of all malignancies. Differential diagnosis may be challenging, considering the variety of clinical entities with similar behavior. About 15 -20% of MM only secretes monoclonal light chains, called light chain MM, which is associated with poorer outcome. Two intermediate concepts were recently introduced, monoclonal gammopathy of renal significance (MGRS) and a wider concept of mono clonal gammopathy of clinical significance (MGCS). The former behaves as a clonal proliferative disorder with associated nephrotoxicity, but does not have the hematological criteria for MM, while MGCS expands this concept to other organs. A subtype of MGCS is monoclonal immunoglobulin deposition disease, a multisystemic disorder characterized by light or heavy chain deposition of monoclonal immunoglobulin in various organs and encompasses three clinical entities: Light -Chain, Light - and Heavy -Chain, and Heavy -Chain Deposition Disease (LCDD, LHCDD and HCDD, respectively). We describe an unusual case of LCDD in which MM was subsequently considered although the proposed criteria are not met. We demon strate the variability of clinical -pathological presentation of LCDD, requiring a rapid decision -making, particularly in terms of kidney and survival outcomesinfo:eu-repo/semantics/publishedVersio