68 research outputs found

    MONITORING AND CHARACTERIZATION OF A SPRING IN A FRACTURED SANDSTONE SLAB

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    Fractured sandstone by tectonic and gravity actions could be classified as aquitard or aquifer according to the number and aperture of the fractures inside the rock mass. This kind of rock mass outcrops not frequently and sparsely in the Apennine and Alps chains. In the Emilian Apennines, which is mainly composed by sedimentary rocks (rich in clay), this type of rock is part of the Epiligurian Succession that outcrops for a 20 percent of the chain. The paper aims to highlight the first results of the semi-continuous water flow monitoring (discharge, electrical conductivity and temperature) and stable isotopic monitoring (delta18O and delta2H) of the spring that represents the drainage point of a vertical fractures system. This network joint characterizes the vertical scarp of a sandstone slab with thickness of 100 meters. The results show that the spring flow rate, the water electrical conductivity, temperature and isotopic values are influenced by the rainfall distribution pattern. Consequently during every rainfall event the spring discharge and water electrical conductivity increase, while the water temperature decreases and isotopic values become more negative. The new infiltrate water reachs the spring with a delay of 10-60 hours. The discharge variability index is around 270 percent. The fractured system is characterized by replacement effect of the preexistent groundwater. During the infiltration event, dissolution phenomena are observed along the wall of the fractures. A preliminary groundwater budget calculation highlights that only a potential infiltration coefficient higher that 75 percent is admitted to justify the total annual volume discharge from the fractures

    Estimating the Isotopic Altitude Gradient for Hydrogeological Studies in Mountainous Areas: Are the Low-Yield Springs Suitable? Insights from the Northern Apennines of Italy

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    Several prior studies investigated the use of stable isotopes of water in hydrogeological applications, most on a local scale and often involving the isotopic gradient (evaluated by exploiting the so-called altitude effect), calculated on the basis of rainwater isotopes. A few times, this gradient has been obtained using the stable isotopic contents of low-yield springs in a limited time series. Despite the fact that this method has been recognized by the hydrogeological community, marked differences have been observed with respect to the mean stable isotopes content of groundwater and rainwater. The present investigation compares the stable isotopic signatures of 23 low-yield springs discharging along two transects from the Tyrrhenian sea to the Po Plain of Italy, evaluates the different isotopic gradients and assesses their distribution in relation to some climatic and topographic conditions. Stable isotopes of water show that groundwater in the study area is recharged by precipitation and that the precipitation regime in the eastern portion of the study area is strongly controlled by a shadow effect caused by the Alps chain on the air masses from central Europe. Stable isotopes (in particular the d18O and deuterium excess (d-excess) contents together with the obtained isotopic gradients) allow us to identify in the study area an opposite oriented orographic effect and a different provenance of the air masses. When the windward slope is located on the Tyrrhenian side, the precipitation shows a predominant oceanic origin; when the windward slope moves to the Adriatic side, the precipitation is characterized by a continental origin. The main results of this study confirm the usefulness of low-yield springs and the need for a highly detailed survey-scale hydrological investigation in the mountainous context

    Stochastic approach to hydraulic barrier design: an example in northeastern Italy

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    Volatile organic compounds, groundwater contamination, multi-layered aquifer syste

    A wireless crackmeters network for the analysis of rock falls at the Pietra di Bismantova natural heritage site (Northern Apennines, Italy)

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    The Pietra di Bismantova (Northern Apennines, Italy) is a large calcareous sandstone rock slab which is distinctively bordered by sub-vertical cliffs that are affected by rock falls, a risk for people visiting the area and for key assets located at the foot of this natural heritage site. A wireless sensor network based on wireless nodes, crack meters and thermometers has been made operative in January 2015 in order to study the response of fractures to changing environmental conditions and support the spatial and temporal zonation of rock fall hazard in this natural heritage site. Results from the first eight months of monitoring show that intense snowfall and low temperatures can determine short-term pulses of fracture opening while the increase of temperature throughout summer determines long-term fracture closing trends. Moreover, as soon as February 2015 one of the crack meters monitored the rapid trend of crack opening that occurred prior to the failure of a large rock slab of about 200 cubic meters

    Identification of miRNAs of Strongyloides stercoralis L1 and iL3 larvae isolated from human stool

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    Strongyloidiasis is a neglected tropical disease caused by the soil-transmitted nematode by Strongyloides stercoralis, that affects approximately 600 million people worldwide. In immunosuppressed individuals disseminated strongyloidiasis can rapidly lead to fatal outcomes. There is no gold standard for diagnosing strongyloidiasis, and infections are frequently misdiagnosed. A better understanding of the molecular biology of this parasite can be useful for example for the discovery of potential new biomarkers. Interestingly, recent evidence showed the presence of small RNAs in Strongyloididae, but no data was provided for S. stercoralis. In this study, we present the first identification of miRNAs of both L1 and iL3 larval stages of S. stercoralis. For our purpose, the aims were: (i) to analyse the miRNome of L1 and iL3 S. stercoralis and to identify potential miRNAs of this nematode, (ii) to obtain the mRNAs profiles in these two larval stages and (iii) to predict potential miRNA target sites in mRNA sequences. Total RNA was isolated from L1 and iL3 collected from the stool of 5 infected individuals. For the miRNAs analysis, we used miRDeep2 software and a pipeline of bio-informatic tools to construct a catalog of a total of 385 sequences. Among these, 53% were common to S. ratti, 19% to S. papillosus, 1% to Caenorhabditis elegans and 44% were novel. Using a differential analysis between the larval stages, we observed 6 suggestive modulated miRNAs (STR-MIR-34A-3P, STR-MIR-8397-3P, STR-MIR-34B-3P and STR-MIR-34C-3P expressed more in iL3, and STR-MIR-7880H-5P and STR-MIR-7880M-5P expressed more in L1). Along with this analysis, we obtained also the mRNAs profiles in the same samples of larvae. Multiple testing found 81 statistically significant mRNAs of the total 1553 obtained (FDR < 0.05; 32 genes expressed more in L1 than iL3; 49 genes expressed more in L3 than iL1). Finally, we found 33 predicted mRNA targets of the modulated miRNAs, providing relevant data for a further validation to better understand the role of these small molecules in the larval stages and their valuein clinical diagnostics

    Calcium-stimulated calcitonin test for the diagnosis of medullary thyroid cancer. results of a multicenter study and comparison between different assays

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    Background: A basal serum calcitonin (Ct) increase >100 pg/mL in patients with a thyroid nodule is consistent with the diagnosis of medullary thyroid cancer (MTC). In cases where the CT test have a slight to moderate increase, the calcium gluconate stimulation test is helpful to increase diagnostic accuracy. However, reliable cut-offs for calcium-stimulated Ct are still lacking. The aim of this study was to evaluate the sex-specific calcium-stimulated Ct cutoffs for the diagnosis of MTC in a multicenter series. A comparison between different Ct assays has been also performed. Methods: 90 subjects undergone calcium-stimulated Ct for a suspected MTC in 5 Endocrine Units between 2010-2021 were retrospectively analyzed. Serum Ct concentrations were assessed by immunoradiometric (IRMA) or chemiluminescence (CLIA) assays. Results: MTC was diagnosed in 37 (41.1%) and excluded in 53 (58.9%) patients. The best calcium-stimulated Ct cut-off to identify MTC was 611 pg/mL in males (AUC =0.90, 95% CI (0.76;1) and 445 pg/mL in females (AUC=0.79, 95% CI (0.66;0.91). Logistic regression analysis showed that both basal (OR 1.01, P=0.003) and peak Ct after stimulation (OR 1.07, P=0.007) were significantly associated with MTC, together with sex (OR=0.06, P<0.001). The "Ct assay" variable was also considered in the logistic regression model, but it was not significantly associated with MTC (OR=0.93, P=0.919). Conclusions: This study indicates that calcium test could be helpful to identify patients with early-stage MTC and those without MTC. A Ct value of 611 pg/mL in males and 445 pg/mL in females are proposed as the optimal Ct cut-offs at the stimulation test

    Colorectal Cancer Stage at Diagnosis Before vs During the COVID-19 Pandemic in Italy

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    IMPORTANCE Delays in screening programs and the reluctance of patients to seek medical attention because of the outbreak of SARS-CoV-2 could be associated with the risk of more advanced colorectal cancers at diagnosis. OBJECTIVE To evaluate whether the SARS-CoV-2 pandemic was associated with more advanced oncologic stage and change in clinical presentation for patients with colorectal cancer. DESIGN, SETTING, AND PARTICIPANTS This retrospective, multicenter cohort study included all 17 938 adult patients who underwent surgery for colorectal cancer from March 1, 2020, to December 31, 2021 (pandemic period), and from January 1, 2018, to February 29, 2020 (prepandemic period), in 81 participating centers in Italy, including tertiary centers and community hospitals. Follow-up was 30 days from surgery. EXPOSURES Any type of surgical procedure for colorectal cancer, including explorative surgery, palliative procedures, and atypical or segmental resections. MAIN OUTCOMES AND MEASURES The primary outcome was advanced stage of colorectal cancer at diagnosis. Secondary outcomes were distant metastasis, T4 stage, aggressive biology (defined as cancer with at least 1 of the following characteristics: signet ring cells, mucinous tumor, budding, lymphovascular invasion, perineural invasion, and lymphangitis), stenotic lesion, emergency surgery, and palliative surgery. The independent association between the pandemic period and the outcomes was assessed using multivariate random-effects logistic regression, with hospital as the cluster variable. RESULTS A total of 17 938 patients (10 007 men [55.8%]; mean [SD] age, 70.6 [12.2] years) underwent surgery for colorectal cancer: 7796 (43.5%) during the pandemic period and 10 142 (56.5%) during the prepandemic period. Logistic regression indicated that the pandemic period was significantly associated with an increased rate of advanced-stage colorectal cancer (odds ratio [OR], 1.07; 95%CI, 1.01-1.13; P = .03), aggressive biology (OR, 1.32; 95%CI, 1.15-1.53; P < .001), and stenotic lesions (OR, 1.15; 95%CI, 1.01-1.31; P = .03). CONCLUSIONS AND RELEVANCE This cohort study suggests a significant association between the SARS-CoV-2 pandemic and the risk of a more advanced oncologic stage at diagnosis among patients undergoing surgery for colorectal cancer and might indicate a potential reduction of survival for these patients
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