41 research outputs found

    Reactive and mixing processes governing ammonium and nitrate coexistence in a polluted coastal aquifer

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    A comprehensive hydrochemical, stable isotope and microbial analyses characterisation has been performed to evaluate the sources of groundwater, nitrogen pollution and degradation processes occurring in an industrial polluted coastal aquifer in the framework of a complex hydrodynamic system. The coexistence of ammonium and nitrate has been observed in almost all the investigated monitoring wells, reaching maximum values of 100 and 200 mg/L for both species. Chloride and potassium concentration coupled with groundwater stable isotopes data show the influence of local and urban recharge and the occurrence of seawater intrusion in areas near the coastline. ή15N–NH4+ values ranging between −4.9 and +14.9% suggest that different processes such as partial nitrification of ammonium, probably anammox activities and sorption, are occurring at the site. The isotope data for NH4+also showed the existence of the remnant of an old fertilizer plume in the downgradient area. The nitrate isotope data ranging between +9 and +46% and +6 and +26% for ή15N–NO3−and ή18O–NO3−, respectively, suggest that nitrate content is attenuated by denitrification and probably annamox. The fast groundwater flow field is one of the reasons for the coexistence of NH4+and NO3− in groundwater, since both compounds can penetrate the reducing zone of the aquifer. The influence of leakage of sewage pipelines on the aquifer cannot be discerned due to the complexities of the nitrogen attenuation processes, also influenced by pumping activities

    Groundwater flow and geochemical modeling of the Acque Albule thermal basin (Central Italy): a conceptual model for evaluating influences of human exploitation on flowpath and thermal resource availability

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    Although the Acque Albule Basin has been studied since the middle of the 19th century, a comprehensive geologic conceptual model of the area has not yet been developed. The natural setting has been heavily modified by anthropic activities. Rapid evolution during the last 25 years has caused many interferences, which have led to a drastic increase of the hazards and linked risks, mainly related to water resource overexploitation and subsidence. The implementation of an exhaustive framework has become mandatory for environmental and management purposes. Starting from a critical review of previous studies, hydrogeologic and hydrogeochemical surveys and related numerical modeling have been carried out in order to achieve a quantitative understanding of the active phenomena and processes. Several hydrogeologic issues have been addressed concerning aquifer recharge areas and the different flowpaths of groundwater in respect to their division into a shallow and a deep circuit. Account has been taken of the groundwater chemistry as a function of water—rock interactions and mixing processes with uprising fluids. Different scenarios of groundwater flow in the Acque Albule aquifer have been built, using previously available piezometric measurements and the hydrodynamic parameters determined by in situ tests. These results led to the formulation of an updated hydrogeologic conceptual model to be further implemented, in which past, present and future anthropic instances and the potential of natural resources of the area have been included and taken into account. A sound conceptual model must rely on the design and development of a logical geo-database in which information is stored, updated and processed. This operational framework can result in a useful tool for land management, surveys planning and design, hazard and risk evaluation, identification of best practices and economic development of the area

    Multi-isotopic regional-scale screening on drinking groundwater in Lombardy Region (Italy)

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    Groundwater represents the main and safest source of water that supply, for drinking purposes, numerous urban and rural communities all over the world. A deep knowledge of aquifer systems in terms of quality, vulnerability and renewability is fundamental to preserve groundwater resources. Thanks to the contribution of different members of Water Alliance in synergy with Sapienza University, during November 2019 a multi-isotopic analysis at regional scale on groundwater tapped for drinking purposes in a wide area of Lombardy Region, has been carried out. The study aimed to improve knowledge about recharge mechanisms, groundwater relative age and impact of human activities on groundwater quality Each Water Alliance supplier selected wells and springs for a total of 121 samples, catching different aquifer groups and distributed from North to South. Groundwater stable isotope analyses were performed on all the monitoring points, instead tritium, nitrogen isotopes (15N and 18O in nitrates), sulphate isotopes (34S and18O) and 13C isotope in Dissolved Inorganic Carbon (DIC), were analysed in selected monitoring wells basing on previous data and major ions concentrations results. Therefore, results confirmed the key role of multi-isotopic approach in defining aquifer recharge processes, relative groundwater age and origin of pollutants, offering a useful tool to point out local issues which can be deeply investigated by each water supplier

    Molecules implicated in glucose homeostasis are differentially expressed in the trachea of lean and obese Zucker rats

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    Recent studies indicate that the processes mediated by the (T1R2/T1R3) glucose/sugar receptor of gustatory cells in the tongue, and hormones like leptin and ghrelin contribute to the regulation of glucose homeostasis. Altered plasma levels of leptin and ghrelin are associated with obesity both in humans and rodents. In the present study, we evaluated the ultrastructure of the mucosa, and the expression of molecules implicated in the regulation of glucose homeostasis (GLUT2, SGLT1, T1R3, ghrelin and its receptor) in the trachea of an animal model of obesity (Zucker rats). We found that the tracheal epithelium of obese animals was characterized by the presence of poorly differentiated cells. Ciliated and secretory cells were the cell lineages with greatest loss of differentiation. Severe epithelial alterations were associated with marked deposit of extracellular matrix in the lamina propria. The expression pattern of GLUT2 and SGLT1 glucose transporters was similar in the trachea of both the Zucker rat genotypes, whereas that of T1R3 was reduced in ciliated cells of obese rats. A different immunolocalization for ghrelin was also found in the trachea of obese rats. In conclusion, the tracheal morphological alterations in obese animals seem to compromise the expression of molecules involved in the homeostasis of glucose

    Redox Dependent Arsenic Occurrence and Partitioning in an Industrial Coastal Aquifer: Evidence from High Spatial Resolution Characterization of Groundwater and Sediments

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    Superlative levels of arsenic (As) in groundwater and sediment often result from industrial pollution, as is the case for a coastal aquifer in Southern Italy, with a fertilizer plant atop. Understanding conditions under which As is mobilized from the sediments, the source of that As, is necessary for developing eective remediation plans. Here, we examine hydrogeological and geochemical factors that aect groundwater As concentrations in a contaminated coastal aquifer. Groundwater has been subject to pump-and-treat at a massive scale for more than 15 years and is still ongoing. Nevertheless, As concentrations (0.01 to 100 mg/L) that are four orders of magnitude more than Italian drinking water standard of 10 g/L are still present in groundwater collected from about 50 monitoring wells over three years (2011, 2016, and 2018). As was quantiïŹed in three dierent locations by sequential extractions of 29 sediment cores in 2018 (depth 2.5 m to 16.5 m b.g.l.), combined with groundwater As composition, the aqueous and solid partitioning of As were evaluated by partition coecient (Kd) in order to infer the evolution of the contaminant plumes. Most sediment As is found in easily extractable and/or adsorbed on amorphous iron oxides/hydroxides fractions based on sequential extractions. The study shows that As contamination persists, even after many years of active remediation due to the partitioning to sediment solids. This implies that the choice of remediation techniques requires an improved understanding of the biogeochemical As-cycling and high spatial resolution characterization of both aqueous and solid phases for sites of interes

    Bitter tastants and artificial sweeteners activate a subset of epithelial cells in acute tissue slices of the rat trachea

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    Bitter and sweet receptors (T2Rs and T1Rs) are expressed in many extra-oral tissues including upper and lower airways. To investigate if bitter tastants and artificial sweeteners could activate physiological responses in tracheal epithelial cells we performed confocal Ca2+ imaging recordings on acute tracheal slices. We stimulated the cells with denatonium benzoate, a T2R agonist, and with the artificial sweeteners sucralose, saccharin and acesulfame-K. To test cell viability we measured responses to ATP. We found that 39% of the epithelial cells responding to ATP also responded to bitter stimulation with denatonium benzoate. Moreover, artificial sweeteners activated different percentages of the cells, ranging from 5% for sucralose to 26% for saccharin, and 27% for acesulfame-K. By using carbenoxolone, a gap junction blocker, we excluded that responses were mainly mediated by Ca2+ waves through cell-to-cell junctions. Pharmacological experiments showed that both denatonium and artificial sweeteners induced a PLC-mediated release of Ca2+ from internal stores. In addition, bitter tastants and artificial sweeteners activated a partially overlapping subpopulation of tracheal epithelial cells. Our results provide new evidence that a subset of ATP-responsive tracheal epithelial cells from rat are activated by both bitter tastants and artificial sweeteners

    Relationship between rainfall and water table in a coastal aquifer: the case study of Castelporziano presidential estate

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    This study is focused on the analysis of seasonal and annual variability in groundwater levels of the coastal aquifer of Castelporziano Presidential Estate, a protected area of 59 Km2 located in the periphery of Rome. A comparison with the local trends of rainfall at “Castello” gauging station at different time scales (monthly, seasonal and annual) has been carried out. The results highlight differences between the coastal area and eastern and northern sector of the Estate. Indeed, the seasonal effect due to local meteoric recharge is direct and regular during the year in the coastal area in respect to the eastern and northern sectors of the Estate. Moreover, annual steady regime and multi-year trend of groundwater levels suggest the contribution from the adjacent volcanic aquifer of Albani Hills. In the latter case, the regional circulation of groundwater is affected by the effects of intense withdrawals. The maintenance of the monitoring network will allow to define the flow paths of the groundwater that characterize the coastal aquifer of Castelporziano

    Hyperthermic superparamagnetic nanoparticles modulate adipocyte metabolism

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    Adipocytes are the principal cellular component in adipose tissue and their excessive hyperplasia or hypertrophy is actively involved in regulating physiologic and pathologic processes such as inflammation, cardiovascular disease, obesity and tumour. The main depot of energy in adipocytes is represented by lipid droplets, intracellular organelles that play fundamental roles in regulation of metabolic processes. An accumulation of such droplets could be a potential biomarker of disease caused by metabolic dysregulation. Recent studies have demonstrated that heat shock is associated with alteration in energy metabolism: the aim of this study is to modulate the energy metabolism of the adipocytes via controlled administration of thermal energy to reduce the number of lipid droplets. We have investigated the effect of controlled heating of adipocytes using an alternating magnetic field (AMF) on samples loaded with superparamagnetic nanoparticles (MNP) as heating agent

    Regenerative potential of the Bichat fat pad determined by the quantification of multilineage differentiating stress enduring cells

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    Published studies regarding Bichat fat pad focused, quite exclusively, on the implant of this adipose depot for different facial portions reconstruction. The regenerative components of Bichat fat pad were poorly investigated. The present study aimed to describe by an ultrastructural approach the Bichat fat pad, providing novel data at the ultrastructural and cellular level. This data sets improve the knowledge about the usefulness of the Bichat fat pad in regenerative and reconstructive surgery. Bichat fat pads were harvested form eight patients subjected to maxillofacial, dental and aesthetic surgeries. Biopsies were used for the isolation of mesenchymal cell compartment and for ultrastructural analysis. Respectively, Bichat fat pads were either digested and placed in culture for the characterization of mesenchymal stem cells (MSCs) or, were fixed in glutaraldehyde 2% and processed for transmission or scanning electron microscopy. Collected data showed very interesting features regarding the cellular composition of the Bichat fat pad and, in particular, experiments aimed to characterized the MSCs showed the presence of a sub-population of MSCs characterized by the expression of specific markers that allow to classify them as multilineage differentiating stress enduring cells.  This data set allows to collect novel information about regenerative potential of Bichat fat pad that could explain the success of its employment in reconstructive and regenerative medicine

    Rehabilitation and biomarkers of stroke recovery: study protocol for a randomized controlled trial

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    Background: Stroke is a leading cause of disability. Nonetheless, the care pathway for stroke rehabilitation takes partially into account the needs of chronic patients. This is due in part to the lack of evidence about the mechanisms of recovery after stroke, together with the poor knowledge of related and influencing factors. Here we report on the study protocol \u201cRehabilitation and Biomarkers of Stroke Recovery,\u201d which consists of 7 work-packages and mainly aim to investigate the effects of long-term neurorehabilitation on stroke patients and to define a related profile of (clinical-biological, imaging, neurophysiological, and genetic-molecular) biomarkers of long-term recovery after stroke. The work-package 1 will represent the main part of this protocol and aims to compare the long-term effects of intensive self-rehabilitation vs. usual (rehabilitation) care for stroke. Methods: We planned to include a total of 134 adult subacute stroke patients (no more than 3 months since onset) suffering from multidomain disability as a consequence of first-ever unilateral ischemic stroke. Eligible participants will be randomly assigned to one of the following groups: intensive self-rehabilitation (based on the principles of \u201cGuided Self-Rehabilitation Contract\u201d) vs. usual care (routine practice). Treatment will last 1 year, and patients will be evaluated every 3 months according to their clinical presentation. The following outcomes will be considered in the main work-package: Fugl-Meyer assessment, Cognitive Oxford Screen Barthel Index, structural and functional neuroimaging, cortical excitability, and motor and somatosensory evoked potentials. Discussion: This trial will deal with the effects of an intensive self-management rehabilitation protocol and a related set of biomarkers. It will also investigate the role of training intensity on long-term recovery after stroke. In addition, it will define a set of biomarkers related to post-stroke recovery and neurorehabilitation outcome in order to detect patients with greater potential and define long-term individualized rehabilitation programs. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT04323501
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