1,189 research outputs found

    Integrated geophysical and geological investigations applied to sedimentary rock mass characterization

    Get PDF
    The Salento Peninsula (south-eastern Italy) is characterized by sedimentary rocks. The carbonatic nature of the rocks means they are affected by karst phenomena, forming such features as sinkholes, collapsed dolines and caverns, as a result of chemical leaching of carbonates by percolating water. The instability of these phenomena often produces land subsidence problems. The importance of these events is increasing due to growing urbanization, numerous quarries affecting both the subsoil and the surface, and an important coastline characterized by cliffs. This paper focuses on geological and geophysical methods for the characterization of soft sedimentary rock, and presents the results of a study carried out in an urban area of Salento. Taking the Q system derived by Barton (2002) as the starting point for the rock mass classification, a new approach and a modification of the Barton method are proposed. The new equation proposed for the classification of sedimentary rock mass (Qsrm) takes account of the permeability of the rock masses, the geometry of the exposed rock face and their types (for example, quarry face, coastal cliff or cavity), the nature of the lithotypes that constitute the exposed sequence, and their structure and texture. This study revises the correlation between Vp and Q derived by Barton (2002), deriving a new empirical equation correlating P-wave velocities and Qsrm values in soft sedimentary rock. We also present a case history in which stratigraphical surveys, Electrical Resistivity Tomography (ERT), and seismic surveys were applied to in situ investigations of subsidence phenomena in an urban area to estimate rock mass quality. Our work shows that in the analysis of ground safety it is important to establish the rock mass quality of the subsurface structures; geophysical exploration can thus play a key role in the assessment of subsidence risk

    Gut microbiota composition and frailty in elderly patients with Chronic Kidney Disease

    Get PDF
    Background Frailty is common in older patients affected by chronic kidney disease (CKD). Since gut microbiota (gMB) may contribute to frailty, we explored possible associations between gMB and frailty in CKD. Methods We studied 64 CKD patients (stage 3b-4), categorized as frail (F, 38) and not frail (NF, 26) according to Fried criteria, and 15 controls (C), all older than 65 years. In CKD we assessed serum C-reactive protein, blood neutrophil/lymphocyte ratio, Malnutrition-inflammation Score (MIS); gMB was studied by denaturing gel gradient electrophoresis (DGGE), high-throughput sequencing (16S r-RNA gene), and quantitative real-time PCR (RT-PCR). Results No differences in alpha diversity between CKD and C and between F and NF patients emerged, but high-throughput sequencing showed significantly higher abundance of potentially noxious bacteria (Citrobacter, Coprobacillus, etc) and lower abundance of saccharolytic and butyrate-producing bacteria (Prevotella spp., Faecalibacterium prausnitzii, Roseburia spp.), in CKD respect to C. Mogibacteriaceae family and Oscillospira genus abundance was positively related to inflammatory indices in the whole CKD cohort, while that of Akkermansia, Ruminococcus and Eubacterium genera was negatively related. Compared with NF, in F there was a higher abundance of some bacteria (Mogibacteriacee, Coriobacteriacee, Eggerthella, etc), many of which have been described as more abundant in other diseases. Conclusions These results suggest that inflammation and frailty could be associated to gMB modifications in CKD

    Visuo-tactile stimulation, but not type of movement, modulates pain during the vision of a moving virtual limb

    Get PDF
    Aims: Evidence has revealed a relationship between pain and the observation of limb movement, but it is unknown whether different types of movements have diverse modulating effects. In this immersive virtual reality study we explored the effect of the vision of different virtual arm movements (arm vs. wrist) on pain threshold from heat applied to the wrist. Patients & Methods: Forty healthy participants underwent four conditions in virtual reality while heat pain thresholds were measured. Visuo-tactile stimulation was used to attempt to modulate the feeling of virtual limb ownership. Results: Effects on pain threshold were present for type of stimulation but not type of movement. Conclusions: The type of observed movement does not appear to influence pain modulation, at least not during acute pain states

    Hydro‐stratigraphic conditions and human activity leading to development of a sinkhole cluster in a Mediterranean water ecosystem

    Get PDF
    Salento Peninsula (Apulia, southern Italy) is characterised by many active sinkholes, which represent the main geological hazard. The stretch of coastline between the village of Casalabate and Le Cesine wildlife reserve is highly affected, with a system of dunes separating the low beach from extensive wetlands, which were subject to uncontrolled urban development after reclamation. The overall morphology is characterized by flat topography, whilst from a hydrogeological standpoint, the mixing of inland freshwater with advancing brackish water favours the higher aggressivity with respect to soluble rocks, and the development of enhanced dissolution (hyperkarst). The relict landscapes within the protected areas still allow for the recognition of actively occurring sinkholes, which cause damage to houses, the road network and infrastructures. In this article the case of Aquatina di Frigole is described, where in the last 15 years numerous sinkholes have formed, with the processes still in rapid evolution. Detailed surveys allow for to identification of the mechanisms of sinkhole formation (suffusion sinkholes), the deriving cluster, and the main hydrogeological links among the different water bodies in the area. Acquatina di Frigole provides an excellent natural laboratory to observe development and evolution of sinkholes, and their relationships with the stratigraphic and hydrogeological elements

    Time variations in the deep underground muon flux measured by MACRO

    Full text link
    More than 30 million of high-energy muons collected with the MACRO detector at the underground Gran Sasso Laboratory have been used to search for flux variations of different natures. Two kinds of studies were carried out: search for periodic variations and for the occurrence of clusters of events. Different analysis methods, including Lomb-Scargle spectral analysis and Scan Test statistics have been applied to the data.Comment: 6 pages, 4 EPS figures. Talk given at the 29th ICRC, Pune, India, 3-10 August 200

    The Trigger and Data Acquisition System for the KM3NeT-Italy neutrino telescope

    Get PDF
    KM3NeT-Italy is an INFN project that will develop the central part of a submarine cubic-kilometer neutrino telescope in the Ionian Sea, at about 80 km from the Sicilian coast (Italy). It will use hundreds of distributed optical modules to measure the Cherenkov light emitted by high-energy muons, whose signal-to-noise ratio is quite disfavoured. In this contribution the Trigger and Data Acquisition System (TriDAS) developed for the KM3NeT-Italy detector is presented. The "all data to shore" approach is adopted to reduce the complexity of the submarine detector: at the shore station the TriDAS collects, processes and filters all the data coming from the detector, storing triggered events to a permanent storage for subsequent analysis. Due to the large optical background in the sea from 40K decays and bioluminescence, the throughput from the sea can range up to 30 Gbps. This puts strong constraints on the performances of the TriDAS processes and the related network infrastructure

    A case study on the application of the MSFD to Mediterranean coastal systems: the Po plume, as a transitional water system in the Northern Adriatic basin.

    Get PDF
    1 - In the frame of the Marine Strategy Framework Directive (MSFD) of the European Community, in order to assess the Good Environmental Status (GES) of the marine coastal and estuarine waters, the eutrophication descriptors include several aspects of the phytoplankton communities (such as composition, abundance and biomass). 2 - Two oceanographic campaigns were carried out in the area off the Po River plume, where a highly dynamic frontal zone separates an inshore and an offshore system. The coupling of size structure and diagnostic pigments of phytoplankton communities in relation to different environmental contexts are tested as an expedite and informative tool to assess water quality sensu MSFD. 3 - The Po plume creates a very dynamic frontal zone, resulting in strong trophic gradients within a relatively small area. 4 - The spatio-temporal variability of salinity in coastal waters and in transitional waters plays a pivotal role in structuring phytoplankton communities. 5 - The dynamics of forcing factors drive changes in cell-size structure, in the functional group composition as well as a shift in size within the same functional group. 6 - The combination of phytoplankton size-structure and chemotaxonomic compositions is proposed as an expedite tool for investigating, at the appropriate scales, the ecology of transitional water systems

    BAFF/APRIL pathway in Sjögren syndrome and systemic lupus erythematosus: relationship with chronic inflammation and disease activity

    Get PDF
    Objectives: BAFF and APRIL belong to the tumor necrosis factor (TNF) superfamily and are crucial for the survival, maturation, and differentiation of B cells. Aim of the study is to evaluate BAFF and APRIL in patients affected by Sjögren syndrome (SS) and systemic lupus erythematosus (SLE). Methods: Sixty patients, (40 SLE, 20 SS) and 20 healthy subjects were enrolled in this study. All subjects were evaluated for laboratory data (ESR, CRP, immunoglobulin G, A and M, complement fragments C3 and C4, LDH, beta2microglobulin, serum levels of rheumatoid factor), autoantibodies (ANA; ENA-SSA, -SSB, -Sm) and lymphocytes subpopulations. For patients, disease activity and damage indexes were assessed with the use of SLEDAI and SLICC and SSDAI and SSDDI for SLE and SS, respectively. BAFF and APRIL were determined by commercial sandwich ELISA kit (R&D Systems, Bender MedSystem). Statistical analysis has been performed with software Prism (Graphpad Instat, version 5.00). Results: APRIL levels were higher among SLE and SS patients compared to controls (p<0.0001, and p0.0001, respectively). BAFF levels in SLE were significantly higher than in SS (p<0.0001). We found higher BAFF levels in SLE and SS compared to controls (p<0.0001). Among SLE patients APRIL correlated with SLEDAI (r 0.3, p 0.04), SLICC (r 0.5,p 0.001), ESR (r 0.3, p 0.005) and CRP (r 0.4, p 0.02). Among SS patients APRIL correlated with SSDAI (r 0.4, p 0.02), SSDDI (r 0.4, p0.01), IgG (r 0.5, p0.01), ESR (r 0.6, p 0.01), CRP (r 0.6, p 0.02) and CD19 B lymphocytes absolute count (r 0.4, p 0.04); BAFF correlated with SSDDI (r 0.7, p 0.004) and CD19 B lymphocytes absolute count (r 0.5, p 0.04). Conclusions: In this study we showed a correlation between disease activity, damage indexes and BAFF/APRIL levels in SLE and SS patients suggesting a role in the strong activation of the immune system in patients with active disease

    Estimation of soil moisture from UAS platforms using RGB and thermal imaging sensors in arid and semi-arid regions

    Get PDF
    Soil moisture (SM) is a connective hydrological variable between the Earth’s surface and atmosphere and affects various climatological processes. Surface soil moisture (SSM) is a key component for addressing energy and water exchanges and can be estimated using different techniques, such as in situ and remote sensing (RS) measurements. Discrete, costly and prolonged, in situ measurements are rarely capable in demonstration of moisture fluctuations. On the other hand, current high spatial resolution satellite sensors lack the spectral resolution required for many quantitative RS applications, which is critical for heterogeneous covers. RS-based unmanned aerial systems (UASs) represent an option to fill the gap between these techniques, providing low-cost approaches to meet the critical requirements of spatial, spectral and temporal resolutions. In the present study, SM was estimated through a UAS equipped with a thermal imaging sensor. To this aim, in October 2018, two airborne campaigns during day and night were carried out with the thermal sensor for the estimation of the apparent thermal inertia (ATI) over an agricultural field in Iran. Simultaneously, SM measurements were obtained in 40 sample points in the different parts of the study area. Results showed a good correlation (R2=0.81) between the estimated and observed SM in the field. This study demonstrates the potential of UASs in providing high-resolution thermal imagery with the aim to monitor SM over bare and scarcely vegetated soils. A case study based in a wide agricultural field in Iran was considered, where SM monitoring is even more critical due to the arid and semi-arid climate, the lack of adequate SM measuring stations, and the poor quality of the available data
    corecore