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This study provides the first micro‐thermometric data of fluid inclusions (FIs) in mafic loose (disaggregated) xenocrysts and ultramafic xenoliths in explosive products of the melilitite‐carbonatite Mt. Vulture volcano (southern Italy). Pure CO2late stage FIs hosted in rock‐forming minerals of wehrlite xenoliths and clinopyroxene xenocrysts were trapped at the local crust‐mantle boundary (32 km). In contrast, trapping pressures within the loose olivine xenocrysts are from 3.2 to 4.5 kbar (8–13 km). Considering the ongoing degassing of mantle‐derived CO2rich gases, together with seismic evidences of the presence of low amount of melts at depth, and the tectonic control of the past volcanic activity, our study opens new perspective about the hazardous nature of the “quiescent” melilitite‐carbonatite volcanoes. The study of fluid inclusions (FIs) (small amount of fluid trapped within minerals) provides important information on variable environments and magmatological processes in which the host minerals were formed. Investigation of the FIs with respect to their composition, trapping pressure and temperature, allow us to constrain magma ascent history. To understand the last explosive volcanic activity of Mt. Vulture volcano (southern Italy), we investigated FIs in mafic minerals and mantle fragments brought to the surface by a melilitite‐carbonatite magma. Our results show the presence of CO2‐rich FIs with trapping pressure corresponding to a depth of 32 km in mantle fragments, and a shallower depth (8–13 km) in mafic mineral. Estimates on magma ascent rate show rapid ascent dynamics to the surface. Our study emphasizes the importance of a multidisciplinary approach that combine geochemistry and petrology to investigate a volcanic system even if the volcano is considered “quiescent,” as is the case of Mt. Vulture volcano, where mantle degassing is still ongoing. Micro‐thermometric analyses show the occurrence of high‐density CO2‐rich fluid inclusions hosted by minerals within wehrlite xenolithsAscent rate between melilitite‐carbonatite (≈20 m/s) and kimberlite (≈45 m/s) magma is comparableMelilitite‐carbonatite volcanoes can be hazardous even after long time of quiescence (>105years) Micro‐thermometric analyses show the occurrence of high‐density CO2‐rich fluid inclusions hosted by minerals within wehrlite xenoliths Ascent rate between melilitite‐carbonatite (≈20 m/s) and kimberlite (≈45 m/s) magma is comparable Melilitite‐carbonatite volcanoes can be hazardous even after long time of quiescence (>105years)

Hepatitis C virus (HCV) variability is mainly attributed to the ability of the virus to respond to host immune pressure, acting as a driving force for the evolution of quasispecies. This study was aimed at studying the changes in HVR-1 heterogeneity and the evolution of HCV quasispecies in HIV/HCV-coinfected patients according to the pattern of response to highly active antiretroviral therapy (HAART).Sixteen HIV/HCV-coinfected patients harbouring HCV genotype 1 and who had been on HAART for at least 1 year, 8 showing increasing CD4+T-cell counts (immunological responders) and 8 showing a stable or decreasing CD4+T-cell counts (immunological non-responders), were selected from a prospective cohort study.After 1 year of HAART, 11 patients showed HIV viral load <2.6 log10cp/ml (virological responders), and 5 showed HIV viral load above this value (virological non-responders). Plasma samples, collected before starting therapy and after 1 year of HAART, underwent clonal sequence analysis for HVR-1 region of HCV. Non-synonymous/synonymous substitutions ratio (Ka/Ks), aminoacidic complexity (normalized Shannon entropy) and diversity (p-distance), were considered as parameters of quasispecies heterogeneity. After 1 year of HAART, heterogeneity of HVR-1 quasispecies significantly decreased in virological non-responders, whereas the heterogeneity tended to increase in virological responders. The differences in the evolution were less stringent, when considering immunological response. On the other hand, profound qualitative modifications of HVR-1 quasispecies were observed only in patients with both immunological and virological HAART response.On the whole, these findings suggest that, in patients undergoing HAART, the extent of HCV variability and the evolution of HVR-1 quasispecies is influenced by the pattern of response to antiretroviral therapy.

The prognostic role of GB virus type C (GBV-C) viraemia in HIV-infected subjects treated with highly active antiretroviral therapy (HAART) is still undefined, The aim of this analysis is to assess the relationship between GBV-C infection and response to antiretroviral therapy among HIV-infected subjects initiating HAART when antiretroviral-naive.A prospective, observational study of 400 HIV-infected patients with measurements of GBV-C RNA, hepatitis C virus (HCV) antibodies and HCV RNA determined from plasma stored prior to HAART initiation, Time to virological (achieving HIV RNA =500 copies/ml) and immunological success (a CD4+ count increase of =200cells/µl), and the time to virological relapse (confirmed HIV RNA >500 copies/ml) were assessed by Kaplan-Meier methods and Cox proportional hazard regression model.Of the subjects, 117 (29.3%) were GBV-C positive and, overall, 351 (87.8%) patients achieved virological success, After controlling for a number of confounders including HCV RNA, GBV-C viraemic patients experienced a significantly lower risk of HIV rebound than those who were GBV-C negative [relative hazard (RH)=0.56, 95% CI: 0.34–0.93, P=0.03], Conversely, the probability of achieving initial virological success or CD4+ count response after HAART did not differ between GBV-C-negative and -positive subjects, These results suggest that GBV-C coinfection may play a role in determining the rate of HIV rebound possibly by competing with HIV replication after HIV load has been successfully suppressed by HAART.

We examined the impact of a lamivudine-containing highly active antiretroviral therapy (HAART) regimen on 164 hepatitis B virus/HIV co-infected individuals starting their first HAART. Lamivudine-treated patients (accounting for 73% of the study population) showed a significantly lower level of alanine aminotransferase over follow-up [–81.1 mU/ml mean difference; 95% confidence intervals (95% CI): –30.3; –131.7, P=0.003] and a significantly reduced risk of liver-related morbidity/mortality [Relative hazard (RH)=0.07; 95% CI: 0.01–0.38, P=0.002] than those starting a lamivudine sparing-regimen.

High level HIV-1 drug resistance in recently infected treatment-naive individuals correlates with sub-optimal virological responses to highly active antiretroviral therapy (HAART). To determine whether genotypic HIV-1 drug resistance in chronic naive patients, as interpreted by various systems, could predict the virological outcomes of HAART, isolates from patients enrolled in a prospective observational cohort (ICoNA) prior to treatment start were genotyped. Genotypic susceptibility scores (GSS) assigned to the initial HAART regimens using the interpretations of pre-therapy resistance mutations by 13 systems were related to virological outcomes. Of 415 patients, 42 (10%) had at least one major resistance mutation. According to the different interpretations, 1.9–20.5% of patients had some level of resistance to at least one drug in the initial regimen. In multivariable analysis, GSS from two systems significantly predicted the time to virological success: Rega 5.5, for each unit increase in GSS adjusted relative hazard (RH) 1.86 [95% confidence intervals (95% CI): 1.15–3.02] and hivresistanceWeb v3, RH 1.87 (95% CI: 1.00–3.48). With three other systems, GSS showed a trend towards a significant prediction of success: Retrogram 1.6, RH 2.33 (95% CI: 0.98–5.53), Menéndez 2002, RH 2.36 (95% CI: 0.97–5.72) and Stanford hivdb, RH 2.06 (95% CI: 0.94–4.49). Genotypic resistance testing coupled with adequate interpretation in chronic naive patients can usefully identify those at risk of sub-optimal virological response to HAART.

It is demonstrated that the growth of the mixing zone generated by Rayleigh–Taylor instability can be greatly retarded by the application of rotation, at least for low Atwood number flows for which the Boussinesq approximation is valid. This result is analysed in terms of the effect of the Coriolis force on the vortex rings that propel the bubbles of fluid in the mixing zone.

Laboratory experiments have shown that monopolar isolated vortices in a rotating flow undergo instabilities that result in the formation of multipolar vortex states such as dipoles and tripoles. In some cases the instability is entirely two-dimensional, with the vortices taking the form of vortex columns aligned along the direction of the ambient rotation at all times. In other cases, the vortex first passes through a highly turbulent three-dimensional state before eventually reorganizing into vortex columns. Through a series of three-dimensional numerical simulations, the roles that centrifugal instability, barotropic instability, and the bottom Ekman boundary layer play in these instabilities are investigated. Evidence is presented that the centrifugal instability can trigger the barotropic instabilities by the enhancement of vorticity gradients. It is shown that the bottom Ekman layer is not essential to these instabilities but can strongly modify their evolution.

Laboratory observations and numerical experiments have shown that a variety of compound vortices can emerge in two-dimensional flow due to the instability of isolated circular vortices. The simple geometrical features of these compound vortices suggest that their description may take a simple form if an appropriately chosen set of functions is used. We employ a set which is complete on the infinite plane for vorticity distributions with finite total enstrophy. Through projection of the vorticity equation (Galerkin method) and subsequent truncation we derive a dynamical system which is used to model the observed behaviour in as simple as possible a fashion. It is found that at relatively low-order truncations the observed behaviour is qualitatively captured by the dynamical system. We determine what the necessary ingredients are for saturation of instabilities at finite amplitude in terms of wave–wave interactions and feedback between various azimuthal components of the vorticity field.

The authors, after general consideration of family planning programs, present a study of 22 714 women, who, in the decade 1983–1993, required contraceptive protection from the Family Planning Centers in the region of Vigevano (Italy). The authors underline the importance of a protocol used before beginning treatment to help prevent women receiving methods carrying too great a health risk. The results show a very high prevalence of oral contraception, increasing in recent years with the introduction of triphasic pills, while use of intrauterine contraception seems to be declining. Other conventional methods, such as barrier (diaphragm and condom) and ‘natural’ methods, had a low incidence in the sample studied. The reasons for these behaviors are analyzed and the relative trends discussed.

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The nonlinear stability properties of stationary exact nonzonal solutions for inviscid ilow over topography are examined within a barotropic model in spherical geometry. For stationary solutions, such that the potential vorticity is proportional to the streamfunction, necessary and sufficient conditions for nonlinear stability are established. For a truncated system with rhomboidal truncation wave number J these are that the solid body rotation component of the zonal wind ui be negative, corresponding to westward flow, as J → ∞. These results are established by using the methods of statistical mechanics. The sufficient condition for stability is also established by applying Arnol'd's method.The results are illustrated by numerical calculations. The stationary solutions are perturbed by disturbances in the streamfunction fields or by small changes in the topographic height; the climatic states for the system are obtained directly using statistical mechanics methods. The nonlinear stability properties of the stationary solutions are obtained by comparing the stationary solution with the climate, which for inviscid flow is shown to be unique.Stationary flows for which ui is eastward, are found to be unstable even in the limit as the streamfunction perturbation or change in the topographic height vanish. Large amplitude transient waves are generated which break the time invariance symmetry of the initial stationary flows. In contrast, for stationary flows with westward ui, the climate is identical to the initial flow in the limit as the initial streamfuncton perturbation or the change in the topographic height vanishes.The linear instability characteristics of the stationary solutions are also obtained by solving a linear eigenvalue problem. The difficulties in establishing the stability properties of more general exact solutions, where the streamfunction is a general differentiable function of the potential vorticity, within numerical spectral models are discussed.

A vortex approaching a no-slip wall ‘rebounds’ due to the creation of vorticity at the wall in a viscous boundary layer. Here it is demonstrated that a purely inviscid mechanism can also produce vortex rebound from a slip wall. In inviscid vortex rebound, vortex tube stretching generates the necessary vorticity to allow rebound, eliminating the need for viscous vorticity generation. This vortex stretching mechanism is demonstrated through numerical simulations and laboratory experiments on dipole-vortex rebound from a boundary. In an application to oceanography, numerical simulations of both quasi-geostrophic and shallow water dynamics are used to show that the β-effect at an eastern boundary can produce this inviscid rebound. Through a series of numerical experiments in which the strength of the β-effect is varied, a formula for predicting the point of separation of the vortices from the boundary in a dipole–coast collision is deduced. Through simulations, the flux of vorticity and fluid away from the boundary is measured as a function of β and initial angle of incidence. It is found that, in contrast to viscous vortex rebound, which typically does not produce a flux of material away from the boundary farther than a distance comparable to the initial vortex radius, the β-induced rebound does carry fluid far from the coast. Laboratory experiments in a rotating tank are used to show that a sloping bottom can also provide an inviscid mechanism for dipole-vortex rebound from the wall of the tank under certain conditions. A relation determining the conditions under which inviscid or viscous processes will dominate in the rebound of the dipole from a boundary is obtained.

Numerical experiments are used to study the evolution of perturbed vortex tubes in a rotating environment in order to better understand the process of two-dimensionalization of unsteady rotating flows. We specifically consider non-axisymmetric perturbations to columnar vortices aligned along the axis of rotation. The basic unperturbed vortex is chosen to have a Gaussian cross-sectional vorticity distribution. The experiments cover a parameter space in which both the strength of the initial perturbation and the Rossby number are varied. The Rossby number is defined here as the ratio of the maximum amplitude of vorticity in the Gaussian vorticity profile to twice the ambient rotation rate. For small perturbations and small Rossby numbers, both cyclones and anticyclones behave similarly, relaxing rapidly back toward two-dimensional columnar vortices. For large perturbations and small Rossby numbers, a rapid instability occurs for both cyclones and anticyclones in which antiparallel vorticity is created. The tubes break up and then re-form again into columnar vortices parallel to the rotation axis (i.e. into a quasi-two-dimensional flow) through nonlinear processes. For Rossby numbers greater than 1, even small perturbations result in the complete breakdown of the anticyclonic vortex through centrifugal instability, while cyclones remain stable. For a range of Rossby numbers greater than 1, after the breakdown of the anticyclone, a new weaker anticyclone forms, with a small-scale background vorticity of spectral shape given approximately by the −5/3 energy spectral law.

It is now widely accepted that one of the major issues for the future deep sub-micron integrated circuit (IC) technologies regarding yield, device performance and stability and device and product reliability, is the mechanical stress built up in the layers and substrate. It is therefore important to give a quantitative account of these stresses and this can only be achieved by disposing of reliable, performant (as to spatial resolution) and quantitative techniques for the local stress determination in the substrate, of adequate and dedicated process simulation tools and of sensitive methods to analyse the stress effects on device performance.The only experimental technique presently available which allows the strain field distribution in sub-micron CMOS devices is the convergent beam electron diffraction technique of the transmission electron microscopy. Its sensitivity is of the order of 10-4and its spatial resolution is of 1 nm if a TEM/FEG is employed.

In the last years great interest has been devolved to evaluate the role of B-cell dysfunction in the etiology of AIDS-related Non-Hodgkin Lymphoma (NHL) by directly measuring serum-based markers of B-cell stimulation. Serum free light chains (sFLC) has been proposed as sensitive markers of AIDS-related NHL. Role of sFLC in HL in HIV-infected people has not been completely assessed, and the influence of cART on this marker remains unknown. We evaluated the prognostic value of sFLC to predict the risk of AIDS-related NHL and HD in HIV-infected patients.The design was a case-control study nested within ICONA. Of 6500 participants enrolled from 1997 to 2007, 86 patients with incident lymphoma were proposed as cases. Information on cancers was obtained prospectively by using medical record review. 46 of 86 patients with lymphoma (NHL =30; HD=16) were included as cases (n=46) because they had no other co-morbidity and a plasma sample available stored before diagnosis of lymphoma. A total of 138 sample-cases were matched 1:1 to lymphoma-free sample-controls (matching for sex, age, distance from diagnosis/selection stratified as 0–2, 2–5, and >5 years). All samples were assessed for quantitative levels of sFLC. Serum or plasma samples stored at -80C were analyzed for quantitative levels of κ and λ sFLC in the Chemistry Laboratory of INMI “L. Spallanzani” in Rome. sFCL concentrations were determined by using the quantitative FLC assay (Freelite; The Binding Site, Birmingham, UK) performed on a Dare-Behring BNII Nephelometer. The assay separately measures κ sFLC (normal range, 0.37 to 1.94 mg/dl) and λ sFLC (normal range, 0.57 to 2.63 mg/dl). A conditional logistic regression was used to identify predictors of lymphoma.The κ and λ and κ+λ sFLC values were significantly higher in patient with lymphoma than in controls (p=0.008, 0.002, 0.003 respectively). In multivariate analysis sFLC strongly predicted the risk of lymphoma in a dose dependent manner, independently from CD4 count and effective therapy. Longer duration with a suppressed viremia was independently associated with a lower risk of lymphoma. Same results were found for the subgroup of subjects with HD and that with NHD.Elevated sFLC was a strong and sensitive marker of risk of development of NHL and HD in HIV-infected individuals. Decreasing lymphoma risk was independently associated with increasing cumulative time spent with HIV viremia < 400 cp/ml. This could reflect the detrimental effects on immune status associated with absence of treatment or incompletely effective HAART or other disturbances of immune function such as chronic immune activation and the direct effects of HIV on B-cells. Subjects with sFLC >50% of normal threshold at most recent samples (0-3 years) showed an increased risk of lymphoma than subjects with the same levels of sFLC at an earlier sample. Our results seems indicate a weak association between elevated sFLC and risk of death/relapse among subjects with lymphomas.No relevant conflicts of interest to declare.

Abstract 3089

Treatment of aucubin (I) with Hg(II) acetate (II) gives the organo‐mercury compound (III) which undergoes reductive demercuration, forming isoeucommiol (IV) or a mixture of (IV) and 3‐epi‐isoeucommiol (VII).

Staphylococcal endocarditis is a condition affecting intravenous drug abusers at increasing rates, and its treatment is still controversial. We used, successfully, high doses of rifampicin, associated with an aminoglycoside, for the treatment of two heroin addicts. In the first we found a left-sided endocarditis with metastatic abscesses in brain, both kidneys, liver and spleen; in the other the finding of bilateral lung abscesses was related to embolic episodes from a diseased tricuspid valve. Since the isolated strains of Staphylococcus aureus were tolerant to methicillin, we used oral rifampicin (20 mg/kg/day) plus an aminoglycoside (amikacin in the former and gentamicin in the latter), after in-vitro testing had proved these combinations to be effective. We achieved, in both cases stable bactericidal concentrations in the serum and a lasting clinical recovery.