583 research outputs found

    Karst geomorphology of the “Canale di Pirro” polje, Apulia (Southern Italy).

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    In karst environment, a geomorphological map is a powerful instrument, which play a crucial role in understanding earth surface processes and landscape evolution. Furthermore, it could be very useful for speleological perspectives, natural resources exploitation and geo-hazards management (flood, sinkhole, subsidence, etc.), providing useful information that enhance the knowledge of the territory. In this work, we present a geomorphological map of the polje of “Canale di Pirro”, sited in the central part of Apulia Region, in Southern Italy, among the most interesting karst lands in the Mediterranean area. The map covers150km2withanelevationrangeof100-450ma.s.l.Thisareaisoneofthemostremarkablekarstlandforms in the region, characterized underground by a very interesting system of caves, that reaches the water table at a depth of -264 meters. The karst system, known as “Inghiottitoio di Masseria Rotolo”, following scuba-diving exploration below the watertable, has become with a depth of 324m, the deepest known cave in Apulia. The polje is bounded on both sides by tectonically-controlled ridges, showing an overall length of some 12 km. In ancient maps, dating back to the 16th century, the area is represented as crossed by a long river, called Cana. The map obtained derives from the integration of interpretation of aerial photographs, analysis of a digital elevation model and field surveys in order to obtain a correct distribution of landforms and fluvial processes, such as different varieties of karst depressions, conical hills, erosional gullies, alluvial fans and tectonic structures. It provides relevant information about the surface drainage processes, and for understanding, among other things, the groundwater circulation and the related recharge processes. This geomorphological map is part of a wider project, that combined geological, hydrogeological research and chemical analyses of the groundwater. It provides support to the ongoing studies of this part of Apulia region aimedto betterunderstand thegeological processes that originatedthe polje and its later evolution, and the related underground cave system. Further, it might also suggest possible improvements in land management and in the future choice of useful tools for the control of the quality and quantity of karst groundwater

    An integrated approach to elaborate 3-D geological and geotechnical models: a case study from the Daunia Sub-Apennine (Apulia, southern Italy).

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    In the Daunia Sub-Apennine (Apulia, southern Italy) slope instability processes due to rainfalls and earthquakes are widespread and cause significant damage to buildings and other structures, and, in some cases, loss of life. A detailed slope stability assessment requires information on the predisposing and triggering factors, and a good knowledge of the geological and environmental conditions as well. As concerns seismic-induced landslides, conventional methods used for slope stability analysis can be divided in: i) force-based pseudo-static methods, ii) displacement-based methods, and iii) stress-strain methods. Detailed representations of geological and geotechnical units as well as static and dynamic geotechnical characterization of materials have to be considered for the correct choice of the method for slope stability analysis, since these are fundamental for slope behaviour prediction and modelling. The purpose of this paper was to present a methodological approach for elaborating detailed 3-D geological and geotechnical models for areas very heterogeneous in terms of geological and soil properties. In the southern portion of the eastern Daunia Sub-Apennine, the outermost formations of the chain domain crop out. These are represented by the Cretaceous-Miocene and Pliocene wedge-top basin units, followed upwards, in the easternmost portion, by the Plio-Pleistocene foredeep units and by Quaternary filling deposits. A high susceptibility to slope failures for the area is testified by the large number of slope movements consisting in mud flows, roto-translational and composite landslides, and soil slips. Field variability of the slope movements from site to site for mechanisms, velocity, depth of rupture surfaces and volume of materials involved is due to the presence of structurally complex formations, characterised by very poor mechanical properties and high variability of their lithological and structural features. The construction of geological and geotechnical models able to represent realistic information is conditioned by the efficacy of the methods used for assessing the spatial lithofacies distribution and parametrization. The case study of Deliceto is here presented, where the 3-D geological model was built based on the results of stratigraphic correlations between core logs and 2-D geological sections. In-situ surveys were performed by means of classical geological and geomorphological methods, and continuous coring boreholes. Silty-clayey sandstone materials (Conglomerates and Sandstones of Castello Schiavo) crop out along the slopes and rest on clayey silts and marls of turbidite origin (Flysch di Faeto). The Flysch di Faeto Fm. is a structurally complex geological unit which consists of three main lithofacies: 1) silty clays; 2) silty marly clays 3) marls and shales. A series of geotechnical laboratory tests, carried out in accordance with international standards for the static and dynamic characterization of materials, made it possible to obtain a detailed 3-D geotechnical model. In particular, resonant column (RC), cyclic torsional shear (CTS) and standard and cyclic triaxial (TXC) tests were performed on the silty clayey geotechnical unit of the Flysch di Faeto Fm., because it is highly susceptible to geotechnical fatigue resulting from cyclic stresses. The results of the laboratory tests confirmed a variable post-cyclic degradation in the range 40-80% and 12-36%, respectively for the secant shear modulus (G) and the undrained cohesion (cu) associated with an increase between 2.92% and 19.90% for the damping ratio (D), demonstrating the heterogeneity of the material in terms of geological and geotechnical characteristics

    Droplets generated from toilets during urination as a possible vehicle of carbapenem-resistant Klebsiella pneumoniae

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    BACKGROUND: In the health care setting, infection control actions are fundamental for containing the dissemination of multidrug-resistant bacteria (MDR). Carbapenemase-producing Enterobacterales (CPE), especially Klebsiella pneumoniae (CR-KP), can spread among patients, although the dynamics of transmission are not fully known. Since CR-KP is present in wastewater and microorganisms are not completely removed from the toilet bowl by flushing, the risk of transmission in settings where toilets are shared should be addressed. We investigated whether urinating generates droplets that can be a vehicle for bacteria and explored the use of an innovative foam to control and eliminate this phenomenon. METHODS: To study droplet formation during urination, we set up an experiment in which different geometrical configurations of toilets could be reproduced and customized. To demonstrate that droplets can mobilize bacteria from the toilet bowl, a standard ceramic toilet was contaminated with a KPC-producing Klebsiella pneumoniae ST101 isolate. Then, we reproduced urination and attached culture dishes to the bottom of the toilet lid for bacterial colony recovery with and without foam. RESULTS: Rebound droplets invariably formed, irrespective of the geometrical configuration of the toilet. In microbiological experiments, we demonstrated that bacteria are always mobilized from the toilet bowl (mean value: 0.11 ± 0.05 CFU/cm2) and showed that a specific foam layer can completely suppress mobilization. CONCLUSIONS: Our study demonstrated that droplets generated from toilets during urination can be a hidden source of CR-KP transmission in settings where toilets are shared among colonized and noncolonized patients

    Linking surgical specimen length and examined lymph nodes in colorectal cancer patients.

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    AbstractAimThe number of examined lymph nodes (NLN) was associated with survival of stages II and III colorectal cancer (CRC) patients. Guidelines recommend examining at least 12 lymph nodes. This study investigated the influence of surgical specimen length on lymph node harvest and compliance with international guidelines.Materials and methodsThis population-based study included 4,724 cases of surgically treated CRC that were diagnosed from 2002 to 2008. Multivariate analyses were performed for the main study variables (age, gender, diagnosis at screening or in symptomatic patients, cancer site, staging, grading, number of positive nodes, neo-adjuvant treatment for rectal cancer, hospital were surgery was performed). Fractional polynomial models investigated the relationship between continuous variables and outcomes.ResultsThe NLN increased over time reaching ≥12 NLN in 64% of cases at the end of the study period. More NLN were associated with young age, right colon cancer, pT3–T4 disease, stages II and III and high grade. Fewer NLN were associated with short surgical specimen length and neo-adjuvant treatment in rectal cancer patients. Use of laparoscopy increased sharply over time.ConclusionsNLN increased over time in accordance with international guidelines. Surgical specimen length correlated with NLN which may determine therapeutic choices, particularly in stage II colon cancer. When harvested lymph nodes are under 10 in number and all are negative, chemotherapy is always recommended. As specimen lengths <20 cm were associated with a high risk of inadequate NLN counts, patients are at risk of over-treatment

    Osteoporosis prevention in postmenopausal female workers : Beneficial effects of silicon dietary supplementation on oxidative status. A pilot study

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    In the last years, the employment of ageing women is increased, and the well-being of these workers, together with the prevention of chronic disabling diseases, is an issue of great importance. Moreover, as postmenopausal ageing is associated with the loss of bone density and consequent increased fracture risk, promoting bone health in these women could be the best strategy for avoiding osteoporotic fractures. We aimed to evaluate the effects of 3-month supplementation with a commercial antioxidant product containing Silica on oxidative status and bone markers in a sample of Italian female workers. Subjects were menopausal and osteopenic women (N=29, age 59.34\ub16.37, mean BMI 26.19\ub14.01 kg/m2). At baseline (T0) and after three-month treatment (T1) bone mineral density (BMD) was evaluated by phalangeal osteosonogrammetry. Haematological, serum biochemical parameters, reactive oxygen species (ROS), total antioxidant capacity (TAC), oxydated low-density lipoproteins (oxLDL) and urinary cross-links pyridinoline (PYD) and deoxypyridinoline (DPD) were assessed. Parametric or non-parametric tests were performed at T0 and T1. To analyse the possible association between two variables a linear correlation test was performed. At T0, slightly high levels of ROS (86% of subjects), oxLDL (59%), Total Cholesterol (T-Chol) (90%) and LDL-Chol (59%) were observed, together with suboptimal or deficient 25-OH vitamin D (98%) concentrations. At T1, oxLDL levels and the ratio oxLDL/LDL-Chol significantly decreased (p&lt;0.01). At T0 significant negative correlations between BMD T-score and cross-links were observed (DPD/Crea: r=-0.57, p=0.001; PYD/ Crea: r=-0.45, p=0.01). At T1, a significant reduction (p=0.03) was observed only for DPD (\u3bcg/L) but not for cross-links normalized by creatinine amounts. In conclusion 3-months Silica supplementation improves significantly oxidative status and bone resorption markers in most postmenopausal female workers, representing a complementary treatment for early phases of BMD reduction

    Oxidative status in different settings and with different methodological approaches compared by Receiver Operating Characteristic curve analysis

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    Objectives: To test the performance of different analytical approaches in highlighting the occurrence of deregulated redox status in various physio-pathological situations. Design and methods: 35 light and 61 heavy smokers, 19 chronic renal failure, 59 kidney transplanted patients, and 87 healthy controls were retrospectively considered for the study. Serum oxidative stress and antioxidant status, assessed by spectrophotometric Reactive Oxygen Metabolites (d-ROMs) and Total Antioxidant Capacity (TAC) tests, respectively, were compared with plasma free (F-MDA) and total (T-MDA)malondialdehyde, both quantified by isotope-dilution-gas chromatography\u2013mass spectrometry (ID-GC\u2013MS). Sensitivity, specificity and cut-off points of T-MDA, F-MDA, d-ROMs and TAC were evaluated by both Receiver Operating Characteristic (ROC) analyses and area under the ROC curve (AUC). Results: Only T-MDA assay showed a clear absence of oxidative stress in controls and significant increase in all patients (AUC 1.00, sensitivity and specificity 100%). Accuracy was good for d-ROMs (AUC 0.87, sensitivity 72.8%, specificity 100%) and F-MDA (AUC 0.82, sensitivity 74.7%, specificity 83.9%), but not high enough for TAC to show in patients impaired antioxidant defense (AUC 0.66, sensitivity 52.0%, specificity 92.9%). Conclusions: This study reveals T-MDA as the best marker to detect oxidative stress, shows the ability of d-ROMs to identify modified oxidative status particularly in the presence of high damages, and evidences the poor TAC performance. d-ROMs and TAC assays could be useful for routine purposes; however, for an accurate clinical data evaluation, their comparison versus a \u201cgold standard method\u201d is required

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

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    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

    La autogestión de emociones y sentimientos para “ser buenas personas”

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    Teachers are often in classroom environmentswhere emotions emerge. In this article we present a teaching approach called “self-management of problems”, in which emotions and their management are addressed in class through the assembly. For example, when students are involved in making decisions and self-managing their problems, different points of view, consonances and dissonances emerge that bring out emotions such as empathy, anger orlove. In order to encourage active participation of students in their assemblies, it is essential for the student to manage some emotions such as shame or fear. We show the results of implementing a training proposal for Selfmanagement of problems for PE at a peri-urban school in Huércal de Almería (Spain), during the academic year 2011-2012. The analysis of what happens in the assemblies from an emotional perspective allows describing and identifying what happens in the process.Los docentes a menudo nos encontramos en clase situaciones en que las emociones emergen y su tratamiento se hace indispensable en el aula. En el presente artículo presentamos una propuesta denominada “autogestión de problemas” en clases de Primaria de Educación Física (EF), en la que las emociones y su gestión son abordadas en clase mediante la asamblea. Por ejemplo, cuando se involucra a los estudiantes a tomar de decisiones y a autogestionar sus problemas surgen diferentes puntos de vista, consonancias y disonancias que hacen aflorar emociones como la empatía, la rabia, el amor, pero también emergen otras cuyo tratamiento es imprescindibles para que se pueda favorecer la participación de todos en las asambleas, como son la vergüenza o el miedo. Mostramos los resultados de implementar una propuesta formativa de autogestión de problemas para EF del CEIP Buenavista (Huércal de Almería, curso 11-12) y el análisis de lo sucedido en las asambleas desde una mirada emocional que permita describir e identificar qué sucede en el proceso
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