54 research outputs found

    Geoelectrical Surveys for Characterization of the Coastal Saltwater Intrusion in Metapontum Forest Reserve (Southern Italy)

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    A geoelectrical survey was carried out in the Metapontum Forest Reserve located along the Ionian coast of the Basilicata region (Southern Italy). In this work we used the method of two-dimensional electrical resistivity tomography for obtaining high-resolution electrical images in the investigated site. In particular, three electrical resistivity tomography, all orthogonal to the coastline, in the investigated area were carried out. To complete and integrate the geophysical data, soil and groundwater samplings, seventeen and five, respectively, were analyzed using chemical physical techniques. Geoelectrical survey, supported by laboratory analysis of soil and water samples have revealed the presence of a process of saltwater in coastal Forest Reserve of Metapontum, which have caused the decline of the existing pine forest with the consequent erosion and desertification problems. The results have disclosed the way to identify and discriminate large areas affected by intensive soil salinization and high resolution electrical images of the subsurface electrical resistivity plays a key role in delineating the saltwater intrusion front in coastal areas. Furthermore, our integrated study represents a contribution to the future programs for the protection, planning, and management of the terrestrial and marine resources in this coastal area

    Efficient and accurate calculation of dispersion relations for intrinsically unstable premixed flames

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    Premixed flames are susceptible to hydrodynamic and thermodiffusive instabilities that wrinkle the flame front and lead to complex multiscale patterns. They strongly impact the flame propagation and dynamics, increasing the speed of a laminar flame by several folds, easily as large as a factor of five for lean hydrogen flames at high pressure. The dispersion relation, which represents the growth rate of the different harmonic components of the perturbation of the flame front for different wavelengths, is useful to understand the dynamics during the linear phase of flame instabilities. In this work, an efficient and accurate approach based on a Fourier analysis of flame wrinkling is proposed to calculate the dispersion relation. Differently from the typical approach based on perturbing the flame with a single wavelength, the flame is perturbed with a spectrum of sine waves and their growth is followed with a spectral analysis. With the present method, the full dispersion relation is computed with a single simulation; this is significantly more efficient computationally than running a series of simulations with a single-wavelength perturbation for each point of the dispersion relation. It is shown that the presented approach is accurate and also solves an issue encountered when a single perturbation is imposed to compute the growth rate of large wavelengths. Several numerical and initialisation parameters, including resolution, domain size, and amplitude of the initial perturbation, are studied systematically and assessed

    Pulmonary delivery of Interleukin 7 provides efficient and safe delivery to the aging immune system

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    Age-associated atrophy of the thymus with coincident reduction in thymopoeisis, decline in thymic output, and subsequent immune dysfunction has been reversed by the use of interleukin-7 (IL-7). In the earlier studies and in clinical trials, delivery of IL-7 has been by multiple injections over several days to maintain effective activity levels in the tissues. This is unlikely to meet with high compliance rates in future clinical use, and so we tested alternate routes of delivery using a technique involving tagging IL-7 with fluorescent dye that emits in the near-infrared region and whose fluorescence can be visualized within the tissues of live animals. We have shown that intratracheal instillation, enabling transfer through the lungs, provides an effective route for delivering IL-7 into the bloodstream and from there into the tissues in older animals. Delivery is rapid and widespread tissue distribution is seen. Comparison of administration either subcutaneously or by instillation reveals that IL-7 delivery by the pulmonary route provides significantly greater transmission to lymphoid tissues when compared with injection. In functional assessment studies, pulmonary administration led to significantly improved intrathymic T cell development in older animals when compared with IL-7 delivered by injection. Furthermore, in these older animals, delivery of IL-7 by intratracheal instillation was not accompanied by any apparent adverse events when compared with controls receiving saline vehicle by instillation or animals receiving IL-7 by subcutaneous injection

    Sensorineural hearing loss in newborns hospitalized in neonatal intensive care unit: an observational study

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    Children hospitalized in Neonatal Intensive Care Units (NICU) present an increased risk for Sensorineural Hearing Loss (SNHL) due to prematurity, hypoxia-ischemia, hyperventilation, low birth weight and the use of ototoxic drugs. The aim of this study was to assess the prevalence of SNHL in newborns hospitalized in a NICU using Transient Evoked Otoacoustic Emissions (TEOAE) and Automated Auditory Brainstem Responses (A-ABR) and analyze the associated risk factors. A sample of 153 newborns hospitalized in NICU underwent TEOAE, A-ABR and clinical ABR to evaluate the presence of hearing deficits. Prevalence of SNHL was calculated and odds ratio for specific risk factors was measured. One-hundred fifteen babies (86.7%) presented normal hearing at TEOAE and A-ABR. Fifteen children had a REFER response at TEOAE and a PASS response at A-ABR. Twenty-five children (16.3%) had a REFER A-ABR and were addressed to clinical ABR. A diagnosis of SNHL was made in 12 (7.8%) newborns. An increased risk of SNHL was observed in preterm children <28 weeks (p=0.0135), in children with neurological disorders (p=0.02), that underwent surgery (p=0.0002), affected from premature retinopathy (p=0.0006), craniofacial malformation (p=0.007) and that had sepsis (p=0.04). Additional risk factors for SNHL in our sample were a maternal disease during pregnancy (p=0.0011), cesarean delivery (p<0.0001) and a twin pregnancy (p<0.0001). SNHL in newborns is correlated with hospitalization in NICU. An accurate hearing screening associated to a rigorous clinical medical collection of data is necessary to promptly identify cases of SNHL in children with a special attention to those hospitalized in NICU and plan proper intervention

    Intermittent antegrade warm cardioplegia reduces oxidative stress and improves metabolism of the ischemic-reperfused human myocardium

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    AbstractThe aim of this study was to compare the effect of intermittent antegrade warm blood cardioplegia and intermittent antegrade cold blood cardioplegia on myocardial metabolism and free radical generation of the ischemic-reperfused human myocardium. Thirty patients undergoing mitral valve procedures were randomly allocated to two groups: group 1 (15 patients) received warm blood cardioplegia and group 2 (15 patients), cold blood cardioplegia. Myocardial metabolism was assessed before aortic clamping, 1 minute after crossclamp removal, and after 20 minutes of reperfusion, by collecting blood simultaneously from the radial artery and coronary sinus. All samples were analyzed for lactate, creatine kinase, reduced and oxidized glutathione, ascorbic acid, fluorescent products of lipid peroxidation, and leukocyte activation (elastase). In all patients, early reperfusion was associated with significant coronary sinus lactate release. In group 2, but not in group 1, significant coronary sinus release of reduced and oxidized glutathione, fluorescent products of lipid peroxidation, and creatine kinase was also found; moreover, arterial-coronary sinus difference of ascorbic acid content was increased only in group 2, suggesting a transmyocardial consumption of this antioxidant vitamin. After 20 minutes of reperfusion, coronary sinus lactate release was no longer present in group 1, whereas significant production was still evident in group 2. In this group, significant coronary sinus release of fluorescent products of lipoperoxidation and reduced and oxidized glutathione was also observed at this time. No significant release of elastase from the coronary sinus was noted in the two groups throughout the study. The left ventricular stroke work index measured at the end of the study indicated a better functional recovery in group 1 than in group 2. In conclusion, intermittent antegrade warm blood cardioplegia protects the myocardium from ischemia-reperfusion injury better than intermittent antegrade cold blood cardioplegia; this phenomenon may be partly due to the decreased tissue oxidant burden mediated by intermittent warm blood cardioplegia. (J THORAC CARDIOVASC SURG 1995;109:787-95

    Transport Infrastructure Surveillance and Monitoring by Electromagnetic Sensing: The ISTIMES Project

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    The ISTIMES project, funded by the European Commission in the frame of a joint Call “ICT and Security” of the Seventh Framework Programme, is presented and preliminary research results are discussed. The main objective of the ISTIMES project is to design, assess and promote an Information and Communication Technologies (ICT)-based system, exploiting distributed and local sensors, for non-destructive electromagnetic monitoring of critical transport infrastructures. The integration of electromagnetic technologies with new ICT information and telecommunications systems enables remotely controlled monitoring and surveillance and real time data imaging of the critical transport infrastructures. The project exploits different non-invasive imaging technologies based on electromagnetic sensing (optic fiber sensors, Synthetic Aperture Radar satellite platform based, hyperspectral spectroscopy, Infrared thermography, Ground Penetrating Radar-, low-frequency geophysical techniques, Ground based systems for displacement monitoring). In this paper, we show the preliminary results arising from the GPR and infrared thermographic measurements carried out on the Musmeci bridge in Potenza, located in a highly seismic area of the Apennine chain (Southern Italy) and representing one of the test beds of the project

    MIKiS: the ESO-VLT Multi-Instrument Kinematic Survey of Galactic Globular Clusters

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    Globular clusters are collisional systems, where stars of different masses orbit and mutually interact. They are the best "natural laboratories" in the Universe for studying multi-body dynamics and their (reciprocal) effects on stellar evolution. Although these objects have been studied since the very beginning of modern astrophysics, little is known observationally about their internal kinematics, thus preventing a complete understanding of their dynamical state, and of their formation and evolutionary history. We present the first results from the Very Large Telescope (VLT) Multi- Instrument Kinematic Survey of Galactic globular clusters (MIKiS), which is specifically designed to provide line-of-sight velocities of hundreds of individual stars over the entire radial extension of a selected sample of clusters. The survey allows the first kinematical exploration of the innermost regions of high-density globular clusters. When combined with proper motion measurements, it will provide the full 3D view in velocity-space for each system. Long- running open issues, such as the accurate shapes of the velocity dispersion profiles, the existence of systemic rotation and orbital anisotropy (and thus the level of relaxation), and the controversial presence of intermediate-mass black holes in star clusters can finally be addressed, impacting our understanding of the formation and evolutionary processes of globular clusters and their interactions with the Galactic tidal field. <P /

    Efficacy and Safety of Artificial Tears Containing Lipidure and Hypromellose for the Treatment of Moderate Dry Eye Disease in Contact Lens Wearers

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    Background and Objectives: Dry eye disease (DED) affects 5–50% of the global population and deeply influences everyday life activities. This study compared the efficacy, tolerability, and safety of novel Respilac artificial tears containing lipidure and hypromellose (HPMC) with the widely used Nextal artificial tears, which are also HPMC-based, for the treatment of moderate DED in contact lenses (CL) wearers. Materials and Methods: In a prospective, single-center, randomized investigation, 30 patients aged ≄18 years, diagnosed with moderate DED, and wearing CL were randomly assigned to the Respilac (n = 15) or Nextal group (n = 15). Patients self-administrated one drop of Respilac or Nextal in both eyes three times daily for 21 days. Changes in the endpoint (visual analogue scale (VAS) score for ocular tolerability, symptom assessment in dry eye (SANDE) score, non-invasive first break-up time (NIF-BUT) results, tear analysis value, meibography results, and CL tolerability results were assessed, comparing treatment groups and time-point evaluations. Adverse events (AEs) were also recorded and evaluated. Results: VAS scores decreased with time (p \u3c 0.001) in both groups, showing no statistically significant difference among them (p = 0.13). Improvements were also detected from screening to end-of-treatment, which were indicated by the SANDE scores for severity and frequency (p \u3c 0.001) and by tear analysis results (p \u3c 0.001) with no observed difference between the Nextal and Respilac arms. NIF-BUT, meibography, and CL tolerability values were shown to be non-significantly affected by treatment and time. There were no AEs detected in this study cohort. Conclusions: Respilac was confirmed to be effective, safe, and well-tolerated. Lipidure-based ophthalmic solution was shown not to be inferior to the currently used Nextal, however, showing improvements in DED symptoms. Within the existing literature, our study is one of the first to report that MPC plus HPMC-containing eye drops are an effective option for the treatment of moderate dry eye disease and desiccation damage prevention in contact lens wearers
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