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Background: To determine the health needs non-nationals, information on disease occurrence is fundamental. Goals: The goal of this study was to assess the clinical and behavioral characteristics of non-Italians with a new sexually transmitted infection (STI). Methods: Data were taken from Italy’s National STI Surveillance System (1991–1999). Results: Of the 61,798 STI cases reported from January 1991 to December 1999, 6847 (11.2%) were diagnosed among non-Italians, 47.1% of whom were Africans. Being a non-Italian patient with an STI was associated with male gender (adjusted odds ratio [AOR], 1.19; 95% confidence interval [CI], 1.11–1.27), youngest age (AOR, 1.71; 95% CI, 1.43–2.04), no formal education (AOR, 20.25; 95% CI, 17.51– 23.42), and having contracted the STI abroad (AOR, 13.98; 95% CI, 12.59 –15.54). The HIV-1 prevalence among non-Italian patients with STIs was 5.5% (95% CI, 4.9 – 6.2), with large differences by continent of origin. The highest prevalence was found among European injecting drug users (54.1%; 95% CI, 37.1–70.1), South American homosexual men (41.6%; 95% CI, 32.0 –51.8), and heterosexuals from Sub-Saharan Africa (8.9%; 95% CI, 7.2–10.8). Conclusions: Non-Italian patients with STIs seem to consist mainly of migrants, and STI transmission patterns differ from those among Italians; this information is important for developing targeted STI prevention efforts. THE MASSIVE MOVEMENT ALONG the modern migration routes represents one of the most important determinants of human health and of modifications in social status worldwide. In addition to the health implications for the migrants themselves, migration has an impact on the healthcare systems of the countries that host these persons. 1 So that these countries can better assess and satisfy the health needs of migrants, and of non-nationals in general, it is necessary to have adequate information on disease occurrence among these populations. Although such data should ideally be provided by national health surveillance systems or large multisite studies, this is rarely the case, and few national health statistics anywhere distinguish between disease cases among non-nationals and those found in the native population. 2

We describe the synthesis of porous spherical nanoaggregates derived by the controlled growth of zeolite LTA on a poliamidoamine (Pamam) dendrimer acting as nano-template. The presence of a strong condensed cationic Na+charge all around the dendrimers, which is responsible for the intense electrostatic inter-particle interaction potential, stimulate the condensed growth of the zeolitic phase onto the dendrimer substrate. Moreover, the screening produced by the zeolite grown on the dendrimer surface promote the entanglement process between the primary units with the formation of large porous clusters. The main features of the self-assembly process has been characterised by means of different techniques such as Small Angle X-ray Scattering (SAXS), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Energy Dispersive X-ray (EDX) microprobe spectroscopy. The finding of our results may open new perspectives in the synthesis of organic–inorganic nanostructured materials based on mesoporous frameworks with new characteristics and properties.

The ElectroSpray Ionization (ESI) developed by Fenn et al. [1] allows to bring large organic molecules (proteins, enzymes etc) as intact and isolated units in the gas phase. The technique is based on the use of a low-concentration solution of the molecule of interest flowing in a small capillary held at high voltage (typically a few kV) with respect to a grounded counter electrode placed some 10-15 mm away. On the tip of the emitter, the surface tension of the liquid cannot support the formed charge and therefore the liquid forms the so-called 'Taylor cone' inside which a Coulomb explosion creates a spray of charged droplets. The size of the droplets continue decreasing as the solvent evaporates by releasing a gas of molecular ions. The ESI process usually takes place in the air (Figure 1a) and then the jet can be transported into a vacuum chamber for the analysis. Originally developed for protein studies with mass spectrometry, ESI was then used with other types of systems (polymers, Nanoparticles, bacteria ...) as well as for different applications, as 'soft-landing' deposition. In these cases, the apparatus combines electrostatic transport and filter devices, to select the ions of interest and guide them towards either a spectrometer for the analysis or a surface for the deposition. Such a device is under construction at the CNR-ISM Montelibretti. Presently, it consists of i) a heated capillary to transport the charged species in vacuum and ii) a first differential pumping stage equipped with an octupole ion guide, see Figure 1b. A vacuum chamber housing a quadrupole mass spectrometer (QMS) for mass-over-charge, m/z, selection of the charged species, followed by a quadrupolar deflector to direct them towards a deposition chamber is being designed and will soon be commissioned. All in all, an in-vacuum 'soft-landing' deposition apparatus opens-up the unique possibility to perform m/z selected deposition in UHV condition of large biomolecular species [2], with control over the kinetic energy of the deposited species. On the other hand it is a quite complex and costly set-up, suffering severe limitations due to the low fluency of the m/z selected species. The main long term goal of the project is to increase the intensity of the ESI beam by mean of a customised, home-made, apparatus in order to make 'soft landing' a competitive technique for nanotechnology applications such as the production of biosensors and organic devices.

The solubilization of HAuCl4 in toluene within optically active reverse micelles and lamellar structures formed by (1R,2S)-Dodecyl(2-hydroxy-1-methyl-2-phenylethyl)- dimethylammonium bromide (DMEB) has allowed us to evidence the complex phenomenology accompanying the confinement of Au salt within these nanostructures. Together with a chloride/bromide exchange process occurring in the first coordination sphere of an Au ion, UV−vis and electronic circular dichroism (ECD) spectra reveal the appearance of an induced dichroic signal attributable to Au complexes entrapped in the hydrophilic domain of the DMEB chiral nanostructures. Interestingly, change of the effective oxidation state and coordination geometry of the gold ion confined in DMEB nanostructures has been inferred by an analysis of the Au and Br X-ray Absorption Fine Spectroscopy (X-ray Absorbition Near Edge Spectroscopy and Extended X-ray Absorption Fine Spectroscopy) signals. Remarkably, bromine, not covalently bonded to the organic part, acts as the vector that transfers the chirality information on the DMEB to the gold complexes. Structural information on the HAuCl4 solubilized in DMEB reverse micelles dispersed in toluene, obtained by SAXS, indicate the formation of elongated clusters consisting of Au complexes stabilized by DMEB, confirming that the chirality transfer occurs in the micellar core of the DMEB and persists in the solid composites obtained by slow evaporation of the solvent.

The dynamic features of bis(2-ethylhexyl)phosphoric acid (HDEHP)/n-octylamine (NOA) mixtures have been investigated as a function of the NOA mole fraction and temperature by (1)H NMR spectroscopy and rheometry. All data consistently suggest a composition-induced glass-forming behavior. The microscopic factors responsible for this behavior have been highlighted and have been explained in terms of driving forces given by HDEHP-to-NOA proton transfer, the tendency of the resulting species to establish H bonds and to spatially segregate the alkyl chains. The study sheds light on the molecular mechanism responsible for the peculiar behavior of transport properties in such systems and furnishes basic knowledge to be used to design novel materials with planned physicochemical properties.

Structural and dynamical properties of bis(2-ethylhexyl)phosphoric acid (HDEHP)/N-methyl formamide (NMF) liquid mixtures in the whole composition range have been investigated by Fourier Transform Infrared spectroscopy (FT-IR), X-rays Diffraction (XRD), and AC complex impedance spectroscopy. Driven by hydrogen bond interactions among HDEHP PO(4)H group and NMF CO and NH groups, and also by steric effects among the HDEHP alkyl chains, the system microstructure is mainly characterized by the coexistence of spatially separated hydrophilic and hydrophobic nanodomains showing local organization and short-range order. The evolution of this structural feature with system composition has been highlighted by FT-IR and XRD. On the other hand, the thermally activated proton mobility within these hydrophilic domains, as pointed out by AC complex impedance measurements, emphasizes the occurrence of a percolating behaviour characterized by percolation threshold at zero. Due to fast proton conduction across the interconnected network formed by the polar groups, some samples showed very high room-temperature conductivity up to 10(-3) S cm(-1).

The complex permittivity of FeCl 3 /AOT/CCl 4 microemulsions in the 1–10 5 Hz frequency range has been measured by the conventional AC complex impedance technique. Measurements as a function of the volume fraction of the dispersed phase (FeCl 3 + AOT) and temperature at fixed salt-to-AOT molar ratio ( R , R = 0.5) show that the entrapment of FeCl 3 clusters significantly enhances the local permittivity of the AOT reverse micelles and the number density of charge carriers resulting from the peculiar state of the confined inorganic salt. An estimate of the apparent static permittivity of the FeCl 3 ionic clusters entrapped in the core of AOT reverse micelles gives the very high and quite surprisingly value of about 237. Moreover, a thorough analysis of conductivity data and of their temperature dependence strongly supports the hypothesis that the charge transport in these systems is mainly sustained by a mechanism of hopping consisting in the continuous jumping of charged species within supra-micellar aggregates of AOT reverse micelles whose aggregation is driven by fluctuating opposite charges on contacting micelles.

Gold nanoparticle/surfactant composites have been synthesized by a novel reduction reaction in the confined space of dry sodium bis(2- ethylhexyl)sulfosuccinate (AOT) or lecithin reversed micelles dispersed in n-heptane and cyclohexane, respectively. The reaction was carried out by adding an opportune amount of anhydrous hydrazine/tetrahydrofuran solution to a suspension of HAuCl4-containing dry reversed micelles dispersed in organic solvent. UV–vis investigation ascertained the formation of stable metal gold nanoparticles and the analysis of FT-IR spectra highlighted the formation of an oriented surfactant monolayer at the nanoparticle surface. Simple evaporation under vacuum of the organic solvent leads to the preparation of very interesting gold nanoparticle/surfactant liquid crystal composites. Such nanocomposites, characterized by WAXS and SAXS, showed the presence of small (radius∼14 A° ) and stable gold nanoparticles dispersed in the surfactant matrix. It has been also emphasized that a simple washing process with ethanol is a suitable method to eliminate the excess of surfactant leaving a novel nanomaterial constituted by gold nanoparticles coated by a monolayer of opportunely oriented surfactant molecules. © 2005 Elsevier B.V. All rights reserved.

This work focuses on the dynamic phenomena emerging in self-assembled transient intermolecular networks formed when two different surfactants are mixed. In particular, the relaxation processes in liquid mixtures composed by bis(2-ethylhexyl)amine (BEEA) and octanoic acid (OA) in the whole composition range has been investigated by dielectric spectroscopy and Brillouin spectroscopy. A thorough analysis of all the experimental data consistently suggests that, mainly driven by acid-base interactions arising when the two surfactants are mixed, supra-molecular aggregates formation causes the slowing down of molecular dynamics. This, in turn, reflects to longer-range relaxations. These changes have been found to be composition-dependent, involving strong departures of the mixture physico-chemical properties from an ideal behaviour, and reflecting the structural and dynamical features of local structures. In particular, the peculiar dynamic processes occurring in these local inter-molecular structures, have been found to be the factors responsible for the observed and quite surprising increase of direct-current conductivity which occurs when two different (and pretty non-conductive) surfactants are mixed. The discovery can be used not only to design novel materials for application purposes but also to shed more light on the basic principles regulating charge migration in structured liquid systems.

A novel approach to synthesize Au/TiO2 nanostructures with interesting optical properties is presented and discussed. It is based on the nanoparticle “cold” or “hot” nanosoldering occurring when two water suspensions of Au and TiO2 nanoparticles are merely mixed at room temperature or laser irradiated after mixing. Thanks to the high fraction and mutual reactivity of surface species, immediately after the mixing process, the encounters between Au and TiO2 nanoparticles in liquid phase are enough for “cold” nanosoldering of gold nanoparticles onto TiO2 nanoparticles to occur. The optical characterizations show that this fast process (timescale less than 1 min) is followed by a slower process, attributable to some change of the Au nanoparticles. This latter process is significantly accelerated by the 532 nm laser light illumination. The structural and optical properties of “cold” and “hot” nanosoldered Au–TiO2 nanoparticles were investigated by TEM, UV–vis and fluorescence spectroscopies. Interesting optical limiting response was detected at laser fluences above 0.8 J/cm2. The nature of the nonlinear effect was investigated by the Z-scan technique, determining both the nonlinear absorption coefficient and the refraction index. Such interesting non-linear optical properties are worth to be tailored for specific applications.

Structural and dynamic features of bis(2-ethylhexyl) phosphoric acid (HDEHP)-n-octylamine (NOA) mixtures as a function of the NOA mole fraction (X-NOA) have been investigated by SAXS, WAXS, IR, dielectric spectroscopy and polarized optical microscopy. In the 0