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The objective of this study was to investigate correlates of risk for having microalbuminuria in individuals with one or more cardiovascular risk factors.The study involved 1919 individuals who attended general practice settings, were aged 55 to 75 yr, and did not have a history of cardiovascular events or diabetes but had one or more cardiovascular risk factors. A tree-based regression technique and multivariate analysis were used to identify distinct, homogeneous subgroups of patients with different likelihood of having microalbuminuria; interaction between correlates of microalbuminuria and risk for microalbuminuria was also investigated.The prevalence of microalbuminuria was 5.9%. Patients who did not have hypertension and had postload glycemia140 mg/dl showed the lowest prevalence of microalbuminuria (1.9%) and represented the reference class. The likelihood of microalbuminuria was seven times higher in men with hypertension and homeostatic model assessment levels in the upper tertile and four times higher in women with the same characteristics. Individuals with hypertension and lower homeostatic model assessment levels and normotensive individuals with postload glycemiaor = 140 mg/dl had a more than three-fold increased likelihood of having microalbuminuria. Treatment with statins was associated with a 54% reduction in the likelihood of having microalbuminuria, whereas levels of triglycerides150 mg/dl and fibrinogen levels in the upper tertile were associated with a significantly higher risk for microalbuminuria.The likelihood of having microalbuminuria in a population-based study of elderly individuals is strongly related to the interaction between the components of the metabolic syndrome, particularly hypertension, insulin resistance, and impaired glucose tolerance.

The analytical capabilities of laser ablation (LA)-ICP-AAS in determining Li, Be and B at trace levels in geological samples have been tested on a series of glass reference materials and natural samples. The LA-ICP-MS instrument used consisted of a sector-field ICP-MS coupled with a laser ablation microprobe operating at either 266 or 213 nm wavelength. Reference glasses from NIST (SRM 612, 614 and 616) and MPI-DING (KL2-G, MOB-G, StHs6/80-G, GOR128-G, GOR132-G, T1-G and ATHO-G) were selected to develop the analytical method and to assess the best instrumental configuration. A series of calcic amphiboles with different Li, Be and B concentrations were also analysed using both LA-ICP-MS and SIMS to test the applicability of the method to natural minerals. Results indicated that with a spot size of 40 mu m the agreement between measured and reference values of Li, Be and B is generally better than 10% for NIST SRM 612 and 20% for NIST SRM 614. Average reproducibility at the 2s level was 10% for Li, 20% for Be and 15% for B. Limits of detection were approximately 100 ng g(-1) for Be and B and 200 ng g(-1) for Li. These results were confirmed by analyses carried out on natural amphiboles and compared well in terms of precision and accuracy with those commonly achieved by SIMS.

The backarc Patagonia mantle underwent pervasive regional re-crystallisation that left only remnants of the pre-existing mantle. Anhydrous xenoliths (dominantly lherzolites and harzburgites, few dunites) are predominant. Xenoliths containing hydrous phases (lherzolites and harzburgites, rare wehrlites) abundantly occur only at G. Gregores. Bulk-rock and clinopyroxene trace element patterns range from predominant LREE-depleted, LILE-enriched and variably Nb-depleted, to LREE-enriched patterns, with negative Zr, Hf and Ti spikes when amphibole is present. V-shaped trace element patterns are found only in rare non-recrystallised xenoliths. Trace element abundances in potential melts calculated from clinopyroxene are similar to arc magmas, but in southern Patagonia fade eastwards to E-MORB-like compositions. Trace element characteristics of bulk-rock and pyroxenes are interpreted as the consequence of two processes: (1) melting in the region of thermal inversion of the wedge, triggered by infiltration of hydrous components; (2) reactive porous flow of the melts into the overlaying mantle. The component triggering melting is inferred to be slab-derived in the western occurrences and a garnet-facies, asthenosphere-derived melt in the eastern occurrences as a consequence of wedge thickening. Differences between northern and southern Patagonia are interpreted to be due to variable contribution of slab components to the wedge. Compared to the southern region, slab-derived melts are tentatively attributed to the subduction of older and colder segments of the Nazca plate in the North.

Serpentinised spinel harzburgites to orthopyroxene-rich spinel dunites recovered during the Ocean Drilling Program (ODP) Leg 195 on top of the South Chamorro Seamount (southern sector of the Mariana forearc, West Pacific Ocean), along with additional spinel harzburgites from Conical and Torishima Seamounts (northern Mariana and Izu-Bonin forearc, respectively), previously collected during the ODP Leg 125, have been investigated to shed light on the nature and evolution of forearc mantle in the intra-oceanic supra-subduction environment. All the samples show a marked heterogeneity in terms of petrographic, mineralogical and geochemical features that suggests a complex, multistage evolution involving, at variable extent, partial melting, reactive porous flow melt migration and subsolidus metamorphic re-equilibration under decreasing T and open system conditions. Geochemical evidence of the interaction between peridotites and various melts/fluids is the ubiquitous enrichment in highly incompatible elements, such as Large Ion Lithophile Elements (LILE). As for the high-T evolution of these peridotites, a three-stages-model is proposed, involving: 1) a former depletion event, during which the IBM forearc peridotites experienced 20-25% polybaric fractional melting during adiabatic upwelling; 2) a second depletion event characterised by a marked impoverishment in modal orthopyroxene, related to the upraise migration of ultra-depleted melts; 3) a late interaction between a relatively small volume of residual melts and the refractory mantle sequence. Oxidation state of the mantle minerals meanly decreases from north (Torishima Seamount) to south (South Chamorro), according to significant different contributions coming from the subducted Pacific Plate. In particular, the absence of a marked oxidation in South Chamorro peridotites suggests that the percolating melts during Stage 2 had not significant slab-derived component. This observation lead us to conclude that a thermal anomaly in the western Pacific mantle rather than the injection of hydrous components must be the “engine” determining the extreme depletion of the oceanic forearc peridotites and the arc formation. In this frame, it is proposed that IBM peridotites during Stage 1 underwent decompression partial melting and contributed to arc volcanism as actual mantle source. Successively, they were emplaced at relatively shallow levels (Stage 2), constituting the top of a strongly refractory mantle column and being percolated by melts produced by plumbing sources of the arc volcanism.

Partition coefficients (Min/L D ) for a series of geochemically relevant elements have been calculated from combined EMP/LA-ICP-HRMS analyses of plagioclase, alkali feldspar, Ti-magnetite, biotite, apatite, and trachytic/trachyphonolitic melt pairs in selected Campi Flegrei rocks. Pl/L D and Kfs/L D values are generally very low for most of the trace-elements but Sr, Ba, and Eu. Kfs/L D for the latter elements record a systematic increase as the melt composition changes from trachyte to trachyphonolite, likely due to increasing structural compliance of the sanidine in the trachyphonolites related to larger Na/K values. Conversely, Kfs/L D values for transitional, highly charged incompatible elements (e.g., LREE) decrease from trachyte to trachyphonolite, possibly in response to the decrease of melt polymerization. Min/L D values for titanomagnetite generally decrease with the increasing melt evolution, the highest values being those measured for Ti, V, and Sc. Ti, Ba, Sc, Rb, Nb, Ta, and V are compatible in biotite in equilibrium with trachytic melt, whereas Cs, Sr, and Pb are incompatible and REE are strongly incompatible, as supported by the extremely low Bt/L D Y (0.003–0.008). Partition coefficients for apatite and trachyphonolitic glass pairs are high for Sr, REE (particularly MREE), and Y, large for Th, U, and V, generally low for HFSE, and variable for other LILE. The comparison of measured Min/L D values for Campi Flegrei trachytes/trachyphonolites with other sets of partition coefficients reported in literature for evolved systems suggests that a reliable data set for magma evolution modeling requires: (1) a thorough preliminary selection of natural samples; (2) the adoption of accurate microanalytical techniques; (3) the direct measurement of Min/L D values for each specific melt composition.