114 research outputs found

    Evaporation-induced soil water flux to design suction drain for low-carbon ground stabilisation : experimental investigation and modelling

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    The suction drain is a novel concept for low-carbon temporary ground stabilisation in clayey soils alternative to jet grouting and ground freezing. Boreholes are drilled into the ground and air is injected to the borehole end through a delivery pipe. The air flowing through the gap between the pipe and the borehole surface backward towards the borehole entry removes water by evaporation and, hence, increases the undrained shear strength of the soil surrounding the drain. There are no studies that allow quantifying soil water evaporation generated by tangential airflow for the case of ‘wind tunnel’ only a few centimetres high over an evaporating surface a few meters long. This paper first presents an experimental investigation on water evaporation induced by air flow. A 3m long wet surface was subjected to tangential air flow into a 40mm gap. Tests were carried out by considering different air velocities and inlet air relative humidity. A model was then formulated to quantify the water evaporation rate for any length of the wet surface. The model parameters were calibrated against one experimental dataset and the model was then validated against an independent dataset. Finally, an empirical equation is proposed to estimate model parameters without the need of carrying out experimental tests. This is based on the vapour transfer coefficient established empirically for evaporation from open water (external air flow), which was found to remain valid for confined evaporation (internal air flow). The paper therefore provides a tool to estimate airflow-induced evaporation to successfully design the suction drains

    Suction drain as a low carbon ground improvement technique : proof-of-concept at the laboratory scale

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    The most common soil reinforcement methods used in tunnelling, such as jet grouting, fiberglass reinforcement and ground freezing, leave spoils into the ground and have high costs of implementation. On the other hand, preloading methods for soils improvement require long construction periods and limit the enhancement of the undrained shear strength to the applied surcharge load or vacuum load. This paper presents the concept of suction drain as an innovative technique for temporary stabilisation of geostructures in soft clayey soils, which overcomes the inconvenience of current soil reinforcement techniques and the limitation of the preloading. Based on suction generated in the ground by the evaporation from pre-drilled holes, the suction drain enables the enhancement of the undrained shear strength in soft clayey soils. The concept and its validation at mock-up scale level are presented in this study. The experimental investigation assessed the capacity of the suction drain to reduce the soil water content via soil water evaporation induced by forced ventilation. The mock-up scale test was then validated numerically via FEM modelling. Finally, the suction drain modelling was extended to an ideal case of tunnelling for assessing the potential impact of the suction drain on undrained shear strength and, hence, on tunnel face stability

    Irrigation with treated municipal wastewater on artichoke crop: assessment of soil and yield heavy metal content and human risk

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    Industrial and municipal wastewaters are often used for irrigating agricultural fields in arid and semi-arid countries, representing the most attractive option to alleviate pressure on fresh-water resources. However, the wastewater may contain various potentially toxic elements and organic matters with highly harmful effects on human and animal health. During two growing seasons of globe artichoke, the effects of irrigation with secondary (SWW) and tertiary (TWW) municipal wastewater on heavy metal soil and plant content were evaluated together with the consequent human risk from artichoke head consumption. The heavy metal contents (i.e., Al, Cd, Co, Cr, Cu, Fe, Ni, Pb, Zn, and Mn) of the irrigation water, soil, plant and yield were analyzed. Total and extractable heavy metals were quantified to determine the bioaccumulation factors, and the health risks to adults and children were determined according to hazard indices. The heavy metal contents of the artichoke heads harvested after SWW and TWW irrigation were lower than the international threshold values and low bioaccumulation factors suggested that these heavy metals did not accumulate in the edible part of the artichoke crop. The hazard indices based on the consumption of the artichoke heads remained <1.0 for both adults and children, thus indicating that the health risks involving the different heavy metals are not significant

    Qualitative characterisation of cultivated and wild edible plants: Mineral elements, phenols content and antioxidant capacity

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    This study investigated the qualitative characteristics of several edible wild herbaceous species, including those most consumed in Foggia Province (southern Italy). Analysis of qualitative characteristics was performed for the edible parts of 11 wild species (Beta vulgaris L., Foeniculum vulgare Miller, Centaurea solstitialis L., Cichorium intybus L., Scolymus hispanicus L., Sonchus oleraceus L., Borago officinalis L., Diplotaxis erucoides L., Diplotaxis tenuifolia (L.) DC, Sinapis arvensis L., Portulaca oleracea L.) and three cultivated species (C. intybus, B. officinalis, D. tenuifolia). The plants were collected from areas in the Foggia countryside, and the edible part of each species was analysed for dry matter, protein, cation and anion contents as well as total phenols and antioxidant activities. Among the cations, calcium was the most differentiated among species, ranging 784 mg kg-1 fresh weight (Fw) for B. vulgaris to 5886 mg kg-1 Fw for S. hispanicus. The nitrate contents were also highly variable, from 75 mg kg-1 Fw for C. intybus to 3874 mg kg-1 Fw for D. tenuifolia. Total polyphenols ranged from 1054 mg GAE mg kg-1 Fw for C. solstitialis to 3664 mg GAE mg kg-1 Fw for S. arvensis. Antioxidant activities ranged from 839 mg TE kg-1 Fw for B. vulgaris to 5658 mg TE kg-1 Fw for C. intybus. Significant differences were also noted between wild and cultivated plants in the qualitative parameters. Total polyphenols and antioxidant activity were higher in wild C. intybus and B. officinalis than in their cultivated counterparts. Multivariate analysis (cluster analysis and linear discriminant analysis) allowed integration of the ANOVA data to determine the qualitative characteristics of the wild species that contribute most to group differences. The results of the present study aims at improve the current knowledges about edible wild species as vegetable sources in the Mediterranean diet

    Prophylactic Treatment of Pediatric Migraine:Is There Anything New in the Last Decade?

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    Migraine is a frequent and very disabling disease, especially at pediatric age. Despite this, there are few controlled data on the prophylactic treatment of primary headaches in this category of age. Given that the recently introduced calcitonin gene-related peptide (CGRP) inhibitors (CGRP-r) are still limited to adulthood, there is no drug with exclusive indication for migraine treatment in pediatric age. This raises several limitations in terms of adherence and effectiveness of the therapy. Moreover, the scenario is complicated by placebo response, which is larger in children and adolescents than in adults and often leads to an improvement in the attack frequency even in absence of any active pharmacological treatment. Our aim was to investigate the real evidence concerning the prophylactic therapy of pediatric migraine by reviewing the clinical studies published between 2010 and 2019

    PCDH19 mutations in female patients from Southern Italy

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    AbstractPurposeMutations in PCDH19, encoding protocadherin 19 on chromosome X, cause familial epilepsy and mental retardation limited to females or Dravet-like syndrome. We wished to explore the causative role of PCDH19 gene (Xq22) in female patients with epilepsy, from Southern Italy.MethodsDirect sequencing of PCDH19 gene was conducted in 31 unrelated female patients with early onset (<1 year of age) epilepsy and a wide spectrum of phenotypes including febrile seizures, focal and generalized forms, with either sporadic or familial distribution.ResultsWe identified two de novo heterozygous novel mutations of PCDH19 gene (p.Arg550Pro, Ile508ProfsX59) in two of 31 unrelated female patients. We also identified a novel silent mutation p.Ser856=.ConclusionsThe present findings confirm that PCDH19 is a major causative gene for infantile onset familial or sporadic epilepsy in female patients with or without mental retardation

    Medication Overuse Withdrawal in Children and Adolescents Does Not Always Improve Headache:A Cross-Sectional Study

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    Background:MOH can be diagnosed in subjects with headache occurring 15 days/month in association with a regular medication overuse, but its existence is not universally accepted. ICHD-3 redefined criteria for MOH, removing the criterion associating drug suspension with headache course. The aim of our study was to compare the rate of patients diagnosed with medication overuse headache (MOH) according to ICHD-2 and ICHD-3 criteria, to verify the degree of concordance. The secondary aim was to verify if drug withdrawal was really associated with pain relief. Methods:In this cross-sectional study, we retrospectively analyzed a sample of 400 patients followed for primary chronic headache at the Headache Center of Bambino Gesu Children's Hospital. We then selected those presenting with a history of medication overuse, and we applied both ICHD-2 and ICHD-3 criteria to verify in which patients the criteria would identify a clinical diagnosis of MOH. Results:We identified 42 subjects (10.5%) with MOH; 23 of them (55%) presented a relief of headache withdrawing drug overuse. Regarding the applicability of the ICHD-2 criteria, 43% of patients (18/42) fulfilled all criteria, while all ICHD-3 diagnostic criteria were satisfied in 76% of patients (32/42). Eighteen patients (43%) satisfied both ICHD-2 and ICHD-3 criteria, while 10 patients (24%) did not satisfy either diagnostic criterion. Conclusions:Our study suggests that in children and adolescents, withdrawing medication overuse is not always associated with a clinical benefit. Therefore, though allowing a MOH diagnosis in a higher rate of patients as compared to ICHD-2, the application of ICHD-3 criteria does not guarantee a true a causal relationship between medication overuse and headache worsening

    Anxiety, Depression, and Body Weight in Children and Adolescents With Migraine

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    Background: There is a lack of studies that explore the possible association between body weight, psychological symptoms, and migraine severity in pediatric populations. The purpose of the study was to explore: (1) the association between body weight and the frequency of migraine attacks, (2) the possible differences in anxiety and depression symptoms according to the frequency of attacks and body weight, and (3) the possible mediating role of anxiety and/or depression in the association between body weight and frequency of migraine attacks in children.Methods: One hundred and eleven children/adolescents with migraine were included (47 boys and 64 girls; mean age 11.7; +/- 2.4 years). The patients were classified as: (1) high frequency patients, reporting from weekly to daily episodes and (2) low frequency patients, with &lt;= 3 episodes per month. According to their body mass index percentiles, the patients were divided in "Normal weight" (from &gt;= 5 to &lt;85 percentile), "Overweight" (from &gt;= 85 to &lt;95 percentile), and "Obese" (&gt;= 95 percentile). Given the low number of obese patients, the overweight and obese groups were considered together in the "Overweight" group. Anxiety and depression symptoms were assessed by the Self-Administered Psychiatric Scales for Children and Adolescents (SAFA).Results: Fifty-four patients were normal in weight (49.6%), while 56 patients (50.4%) were overweight. The overweight patients showed a higher frequency of migraine attacks (64.7%; p &lt; 0.05). Patients with a high frequency of attacks reported higher scores in all SAFA-Anxiety subscales (SAFA-A Tot: F = 15.107; p = 0.000). Overweight patients showed a significantly higher score in the "Separation anxiety" subscale (F = 7.855; p = 0.006). We found a mediating role between the overweight and high frequency for total anxiety (z = 2.11 +/- 0.03; p &lt; 0.05) and social anxiety (z = 2.04 +/- 0.03; p &lt; 0.05).Conclusions: Our results suggest that, among the children suffering from migraine, the overweight status is associated with a higher frequency of attacks and separation anxiety symptoms. In particular, our study provides the first evidence of the role of anxiety in linking overweight and the frequency of migraine attacks in children and adolescents

    From the New Diagnostic Criteria to COVID-19 Pandemic Passing Through the Placebo Effect. What Have We Learned in the Management of Pediatric Migrane Over the Past 5 Years?

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    In 2018, the Food and Drug Administration (FDA) approval of anti-calcitonin gene-related peptide (CGRP) therapies for the treatment of migraine represented a milestone for the management of the disease in adults. On the contrary, the novelties in the field of pediatric migraine are inserted in a different scenario and still concern: (1) diagnostic criteria of the international classification of headache disorders-3 (ICHD-3) that show numerous limits of applicability in the developmental age; (2) the release of the results of the Childhood and Adolescent Migraine Prevention (CHAMP) study that raised doubts about the usefulness of traditional drugs for the treatment of pediatric migraine; (3) the Coronavirus disease 2019 (COVID-19) pandemic has put the spotlight on the importance of managing the psychological factors associated with the disease. In this mini review we discuss the most relevant news in pediatric migraine over the last 5 years
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