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Retention in care is a key feature of the cascade of continuum of care, playing an important role in achieving therapeutic success and being crucial for reduction of HIV transmission. The aim of this study was to evaluate the rate of retention in care in a large referral centre in the North of Italy and to identify predictors associated with failed retention. All new HIV-infected subjects were consecutive enrolled from 1 January 2008 to 31 December 2014. Demographics, immune-virological status, hepatitis co-infection and timing of initiation of combined antiretroviral therapy (cART) data were collected at baseline and at the time of last observation. Failed retention in care was defined as lack of laboratory data, clinical visits and drug dispensation for more than 6 months from the last visit. Cox regression analysis was used. Multivariate analysis of variables with P<0.05 in univariate analysis was performed. We enrolled 269 patients (mean age 46.1 years). Males were 197 (73%), Italian 219 (81%) with mean length of disease of 5.1 years. cART was prescribed for 257 patients (95%). The rate of retention in care was 78.4% and the rate of virological suppression was 75%. Predictors of being loss to follow-up were foreign origin (P = 0.048), CD4+ count <200/mmc (P = 0.001) and not being treated for HIV infection (P = 0.0004). Predictors of cART efficacy were shorter duration of HIV infection and baseline HIV-RNA <100 000 copies/ml. These findings underline the necessity to improve retention in care by identifying groups at increased risk of being loss to follow-up. Retention in care of vulnerable population is crucial to reach 90-90-90 UNAIDS endpoint.
Biomimetic Method has been widely used to prepare calcium phosphate coatings on Ti and its alloys. This modification is based on a Synthetic/simulated Body Fluid (BSF) which facilitates the mimicking of the biological process in order to provide hard tissue repairs. The formation of HA and other calcium phosphates under biological medium and SBF occurs in the presence of Ca2+ and PO43- ions, as well as essential ions such as: Mg2+, HCO3-, K+ and Na+. Ti-15Mo alloy samples were irradiated by pulsed Yb: YAG pulsed laser beam under air and atmospheric pressure. Sequentially, calcium phosphate coatings were deposited on the irradiated surfaces by the biomimetic method. The biomimetic calcium phosphates-based surfaces were submitted to heat treatment conditions at 350°C and 600°C. The present study correlates two conditions of fluency (1,91 and 5,54 J.cm-2) as established have a sufficient energy to promote ablation on the laser beam irradiated surfaces. Likewise, it has been demonstrated the processes of fusion and fast solidification from the laser beam irradiation, under ambient atmosphere, inducing the formation of stoichiometric TiO2 and non-stoichiometric titanium oxides, including Ti3O5, TiO, Ti3O and Ti6O with different oxide percentages depending on the fluency applied. Besides that, laser modification has allowed a clean and reproducible process, providing no traces of contamination, an important feature for clinical applications. The physico-chemical and morphological analysis indicated the formation of a multiphase coatings depending on the heat treatment temperature performed to 350 °C (ACP1 and 2, HAD, HA phases) and 600 °C (HAD, HA and β-TCP phases). It is worth noting that multiphasic bioceramic systems has been gaining attention for biomedical applications. Thus, the laser beam irradiation associated to bioactive coatings of calcium phosphates of biological interest have shown to be promising and economically feasible for use in dental and orthopedic implants.
Coleoid specimens from the Jurassic of northern Chile are included in two different species of Trachyteuthis, i.e., T. covacevichi Fuchs and Schultze, 2008 and T. chilensis n. sp., and in a new genus and a new species, Pseudoteudopsis perezi n. gen. n. sp. The specimens described and figured are from two different areas in northern Chile. Those referred to Pseudoteudopsis perezi n. gen. n. sp. came from a locality north of Calama and are associated with ammonites indicating the lower Callovian uppermost bodenbenderi to lowermost proximum zones (≈ gracilis Standard Zone) of the Andean ammonite zonation. Those described as T. covacevichi and T. chilensis n. sp. came from the Cordillera de Domeyko, northeast of Taltal, and are associated with ammonites indicating the middle Oxfordian transversarium Zone.
Yield responses of a grain amaranth accession to different irrigation strategies were evaluated in Naples, Italy. Field experiments were carried out to evaluate the quantitative and qualitative response of amaranth under combined abiotic stresses (salinity and drought) in a Mediterranean environment of South Italy affected by problems due to groundwater salinization from seawater intrusion.
A comparison was made in 2009 and 2010 between a fully irrigated treatment (1·00), with the restitution of all of the water necessary to replenish to field capacity the soil layer explored by roots (0·00–0·36 m), and two treatments with restitution of 0·50 and 0·25 of the water volume used for the fully irrigated treatment. The three levels of irrigation volume were combined with two levels of salinity, either fresh or salt water, with electrical conductivity (EC) of the irrigation water of 0·64 and 22 dS/m respectively, in a factorial experiment thus harbouring six treatments in a randomized complete block design. The results showed good adaptation of amaranth to drought. It was possible to obtain high yields even if groundwater with infiltrated seawater was used for irrigation (50% yield reduction when the EC of soil saturated paste extract (ECe) was 13·97 dS/m). A reduction of 50% in the volume of irrigation did not cause a significant reduction in yield, whether using fresh or saline water, compared to the treatment fully irrigated with fresh water. The chemical composition of amaranth seeds, however, was significantly affected by the treatments. Starch and ash content decreased with increasing drought while protein content was increased by both salt and drought.
In view of the increased presence of salinity and drought stress in the Mediterranean area and the scarce information on amaranth response to salt and water stress, the aim of the present work is evaluation of the quantitative and qualitative response of amaranth grown in a Mediterranean environment of South Italy under combined drought and salinity stress.
A first attempt to differentiate goethite- and hematite-based natural materials, used for several purposes during the Late Palaeolithic in the Lessini Mountains (Italy), is here proposed. All raw materials were collected from known geological sites within a distance of about 20 km from archaeological excavations (Tagliente and Fumane caves) where ochre fragments were found. X-ray powder diffraction allowed the mineralogical composition of samples collected from carbonate and volcanic geological host and parent rocks to be inferred; in addition, a preliminary distinction based on the different mineral assemblages, on the presence of distinctive mineral phases and on the degree of crystallinity of some compounds such as hematite, became possible. The acquired data thus represent a sort of preliminary inventory for provenance studies on archaeological samples originating in the same region, for which ancillary micro-analytical and geochemical techniques are planned.
The extracellular Ca-sensing receptor (CaSR) is a sensor for a number of key nutrients within the body, including Ca ions (Ca2+) and l-amino acids. The CaSR is expressed in a number of specialised cells within the gastrointestinal (GI) tract, and much work has been done to examine CaSR's role as a nutrient sensor in this system. This review article examines two emerging roles for the CaSR within the GI tract – as a mediator of kokumi taste modulation in taste cells and as a regulator of dietary hormone release in response to l-amino acids in the intestine.
We utilized the new high-order (250-378 mode) Magellan Adaptive Optics system (MagAO) to obtain very high-resolution science in the visible with MagAO's VisAO CCD camera. In the good-median seeing conditions of Magellan (0.5–0.7″) we find MagAO delivers individual short exposure images as good as 19 mas optical resolution. Due to telescope vibrations, long exposure (60s) r' (0.63μm) images are slightly coarser at FWHM = 23-29 mas (Strehl ~ 28%) with bright (R < 9 mag) guide stars. These are the highest resolution filled-aperture images published to date. Images of the young (~ 1 Myr) Orion Trapezium θ1 Ori A, B, and C cluster members were obtained with VisAO. In particular, the 32 mas binary θ1 Ori C1C2 was easily resolved in non-interferometric images for the first time. Relative positions of the bright trapezium binary stars were measured with ~ 0.6–5 mas accuracy. In the second commissioning run we were able to correct 378 modes and achieved good contrasts (Strehl>20% on young transition disks at Hα). We discuss the contrasts achieved at Hα and the possibility of detecting low mass (~ 1–5 Mjup) planets (past 5AU) with our new SAPPHIRES survey with MagAO at Hα.
The Magellan Adaptive Optics (MagAO) system saw first light in November 2012 at Las Campanas Observatory (LCO) on the 6.5m Clay telescope. Here we present an introduction to MagAO's visible wavelength diffraction limited imager, VisAO. VisAO delivers Strehl ratios greater than 30% from 0.62 microns (r') through 1 micron, where Strehl is even higher, and achieved resolutions as small as 20 milli-arcseconds. We took advantage of the excellent performance of MagAO/VisAO to conduct high contrast observations of an exoplanet in the optical. With VisAO, we are, for the first time, able to begin characterizing exoplanet atmospheres in the optical from the ground.
We present the first ground-based adaptive optics images of a silhouette disk. This disk, Orion 218-354, is seen in silhouette against the bright nebular background of Orion, and was resolved using the new Magellan Adaptive Secondary AO system and its VisAO camera in Simultaneous Differential Imaging (SDI) mode. PSF subtraction of Orion 218-354 reveals a disk ~1″ (400 AU) in radius, with the degree of absorption increasing steadily towards the center of the disk. By virtue of the central star being unsaturated, these data probe inward to a much smaller radius than previous HST images. Our data present a different picture than previous observers had hypothesized, namely that the disk is likely optically thin at Hα at least as far inward as ~20AU. In addition to being among the first high-resolution AO images taken in the optical on a large telescope, these data reveal the power of SDI imaging to illuminate disk structure, and speak to a bright future for visible AO imaging. Analysis of the results described briefly here can be found in full detail in Follette et al. (2013).
MagAO is the newly-commissioned adaptive optics (AO) instrument on the Magellan Clay telescope at Las Companas Observatory, Chile. MagAO has two co-mounted science cameras: VisAO for visible-light direct and spectral-differential imaging; and Clio for near to thermal IR direct imaging, non-redundant-mask interference, and prism spectroscopy. We demonstrate MagAO's simultaneous visible and infrared AO performance via direct images of exoplanet Beta Pictoris b. The planet was detected in 5 passbands from 0.9–5μm. Here we show the infrared images; the visible observations are presented in Males et al. 2013. MagAO is the first AO system to offer good performance with extensive coverage across the O/IR spectrum and thus offers an unprecedented opportunity to study the spectral energy distributions of directly-imaged extrasolar planetary atmospheres.
To determine (i) the extent of malnutrition and the risk factors for severe malnutrition in Guinea Bissau, a post-conflict country experiencing long-term consequences of civil war; and (ii) the feasibility and effectiveness of a short-term intervention characterized by outpatient treatment with locally produced food for the treatment of severe malnutrition during the rainy season.
Design and setting
Social, clinical, nutritional information were collected for children reaching the paediatric outpatient clinic of the Hospital ‘Comunità di Sant’Egidio’ in Bissau, Guinea Bissau, from 1 July to 12 August 2003. Severely malnourished children (weight-for-age <−3sd) in poor health status were admitted for daily nutritional and pharmacological treatment until complete recovery. Social and health indicators were analysed to define risk factors of severe malnutrition.
In total, 2642 children were visited (age range: 1 month–17 years). Fever, cough and dermatological problems were the main reasons for access. Social data outlined poor housing conditions: 86·4 % used water from unprotected wells, 97·3 % did not have a bathroom at home, 78·2 % lived in a mud house. Weight-for-age was <−2sd in 23·0 % of the children and <−3sd in 10·3 %; thirty-seven children (1·4 %) were severely malnourished and admitted for day care. All recovered with a weight gain of 4·45 g/kg per d, none died or relapsed after 1 year. Severely malnourished children were mainly infants, part of large families and had illiterate mothers.
Short-term interventions performed in post-conflict countries during seasons of high burden of disease and malnutrition are feasible and successful at low cost; day-care treatment of severe malnutrition with locally produced food is an option that can be tested in other settings.
The scanning electron microscope (SEM) is commonly used to obtain images of a wide variety of samples within a wide range of magnification factors from the order of 10 up to about 105×. This technique is usually applied, but not limited to, the investigation of conductive samples. This is because the interaction of the scanning beam with the sample generates a net charge on the sample surface. Thus, if the sample is conductive, the charge can be quickly disposed of to ground, away from the beam spot. If the sample in non-conductive, the sample becomes locally charged, giving rise to a distortion of the primary beam. In certain conditions, the charge stored on the sample is able to reflect back the incoming electrons, much like an electrostatic mirror.
A characterisation of a low pressure SF6 discharge was undertaken, by means of plasma diagnostics, including radiofrequency electrical probes, Langmuir probes and optical emission spectroscopy. Chemical kinetics modeling of the discharge was performed too. This was aimed to the understanding of a reported transition in the plasma induced surface modification on poly(ethylene terephthalate) (PET) fibres by SF6 plasma treatment which can be characterized as a striking wettability modification reverse displayed by plasma treated fibres as the SF6 pressure in the discharge exceeds a threshold value. Here we have investigated the modification also on different polymeric surface such as that of a PET film and of cellulose (paper). We point out that the observed transition could be understood as a switch between an increased surface hydrophilicity, induced by plasma treatment at low pressure, which produces also surface etching and activation, and an increased surface hydrophobicity, imparted by plasma treatment at higher pressures, due to extended surface fluorination.
Upper Paleozoic Cephalopoda of west-central Patagonia are revised, based on reexamination of all available specimens and of most localities in Chubut Province, Argentina. Nautiloidea Orthocerida are represented by Sueroceras irregulare Riccardi and Sabattini, S.? chubutense (Closs), Sueroceras sp., and Mooreoceras zalazarense Sabattini and Riccardi and Pseudorthoceratidae gen. and sp. indeterminate; Nautilida by Amosiceras reticulatum new genus and species; and Ammonoidea Goniatitida by Glaphyrites taboadai new species and Glaphyrites sp. This fauna belongs to the Cisuralian Sueroceras irregulare and Mooreoceras zalazarense assemblage zones.
We have studied the characteristics of a plasma reactor for the promotion of chemical
reactions aimed to hydrogen reforming from gaseous hydrocarbons. A plasma
torch-like electrode configuration was powered by a limited current, high voltage DC
source. Using as process gas an argon/methane mixture at atmospheric pressure, we
have produced an intermittent spark discharge which has been investigated at
different operating parameters. Experimental information on the discharge have been
used to perform a numerical simulation of the plasma chemical kinetics. The
evolution of the gas-phase composition during and after the interaction in the
discharge region was calculated under different operating conditions. The results have
been used to predict the hydrogen production yield in the experiments and to study the
role played by the different discharge parameters in order to determine the optimal
interaction between plasma and gas mixture.
We describe the scientific rationale and the preliminary optomechanical design for a 2 m class telescope designed to achieve ground layer correction over a ≈15 arcmin Field of View (FoV) to be located at the Dome-C site. The proposed science case is the detection of microlensing events in and by globular clusters and nearby galaxies that, for a high probability of success, requires exceptional seeing (≈0.2 arcsec or better) and a large target density (the centre of a globular cluster with a corresponding telescope FoV of ≈15 arcmin). This approach can capitalise on some of the unique qualities already observed above the Dome-C site, namely that the atmospheric turbulence is largely limited to a ground layer of small thickness only, a relatively low Greenwood frequency and uniterrupted sky coverage during the winter months for objects such as the globular cluster 47-Tuc. Further to the central science case of microlensing the telescope could provide a technological testbed for future telescopes and, given the unique atmospheric properties witnessed already during previous site testing compaigns, has the chance to provide a large amount of data (based on accurate and continuous light curves lasting several months) for fields of research outside that of microlensing. Details of the specific concepts of adaptive optics to be adopted for this telescope are outlined.