29 research outputs found

    A numerical method for Mean Field Games on networks

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    We propose a numerical method for stationary Mean Field Games defined on a network. In this framework a correct approximation of the transition conditions at the vertices plays a crucial role. We prove existence, uniqueness and convergence of the scheme and we also propose a least squares method for the solution of the discrete system. Numerical experiments are carried out

    Reuse of Wasted Bread as Soil Amendment: Bioprocessing, Effects on Alkaline Soil and Escarole (Cichorium endivia) Production

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    In an era characterized by land degradation, climate change, and a growing population, ensuring high‐yield productions with limited resources is of utmost importance. In this context, the use of novel soil amendments and the exploitation of plant growth‐promoting microorganisms potential are considered promising tools for developing a more sustainable primary production. This study aimed at investigating the potential of bread, which represents a large portion of the global food waste, to be used as an organic soil amendment. A bioprocessed wasted bread, obtained by an enzymatic treatment coupled with fermentation, together with unprocessed wasted bread were used as amendments in a pot trial. An integrated analytical plan aimed at assessing i) the modification of the physicochemical properties of a typical Mediterranean alkaline agricultural soil, and ii) the plant growth‐promoting effect on escarole (Cichorium endivia var. Cuartana), used as indicator crop, was carried out. Compared to the unamended soils, the use of biomasses raised the soil organic content (up to 37%) and total nitrogen content (up to 40%). Moreover, the lower pH and the higher organic acid content, especially in bioprocessed wasted bread, determined a major availability of Mn, Fe, and Cu in amended soils. The escaroles from pots amended with raw and bioprocessed bread had a number of leaves, 1.7‐ and 1.4‐fold higher than plants cultivated on unamended pots, respectively, showing no apparent phytotoxicity and thus confirming the possible re‐utilization of such residual biomasses as agriculture amendments

    An ergodic problem for Mean Field Games: qualitative properties and numerical simulations

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    This paper is devoted to some qualitative descriptions and some numerical results for ergodic Mean Field Games systems which arise, e.g., in the homogenization with a small noise limit. We shall consider either power type potentials or logarithmic type ones. In both cases, we shall establish some qualitative properties of the effective Hamiltonian Hˉ\bar H and of the effective drift bˉ\bar b. In particular we shall provide two cases where the effective system keeps/looses the Mean Field Games structure, namely where PHˉ(P,α)\nabla_P \bar H(P,\alpha) coincides or not with bˉ(P,α)\bar b(P, \alpha). On the other hand, we shall provide some numerical tests validating the aforementioned qualitative properties of Hˉ\bar H and bˉ\bar b. In particular, we provide a numerical estimate of the discrepancy PHˉ(P,α)bˉ(P,α)\nabla_P \bar H(P,\alpha)-\bar b(P, \alpha)

    Influence of chemical and mineralogical soil properties on the adsorption of sulfamethoxazole and diclofenac in Mediterranean soils

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    Abstract Background The irrigation with treated wastewaters can be a way for the introduction of organic contaminants in soils. However, their adsorption onto soils can allow a control of their bioavailability and leaching. The adsorption is influenced by properties of contaminants (water solubility, chemical structure) and soils (organic matter content, pH, mineralogy). This study aimed to investigate the effect of mineralogical composition, organic matter content and others parameters of soils on the adsorption of sulfamethoxazole (SMX) and diclofenac (DCF), two contaminants of emerging concerns (CECs), in real cases (Altamura, Sibari and Noci soils). Results The isotherms data showed that the adsorption of the two CECs closely matched the Freundlich model, even if the DCF could also fit the linear one. The only exception was the adsorption of SMX on the soil of Sibari, for which Langmuir's model fitted better. In all cases, the Kd values were the highest for Altamura soil according mainly to its content of organic carbon. Positive correlations were found between Kd value of DCF and the soil organic carbon and Al oxyhydroxides content, suggesting their roles in its adsorption, while SMX showed only a slight positive correlation with the soil organic carbon content. Finally, between the two CECs studied, DCF was more adsorbed than SMX also because of the lower water solubility of the former. Conclusions The good interaction between DCF and soil organic carbon suggests the organic amendment of soils before the application of treated watewaters. The low adsorption of SMX onto soils suggests greater leaching of this compound which is, therefore, potentially more dangerous than DCF. For this reason, the application of a filtration system with appropriate adsorbent materials before the application of wastewater to soils should be expected. Graphical Abstrac

    Validation of a modified QuEChERS method for the extraction of multiple classes of pharmaceuticals from soils

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    Abstract Background The quick, easy, cheap, effective, rugged, and safe (QuEChERS) method can be employed for multi-residue analyses instead of traditional extraction methods due to its advantages in terms of extraction time and required equipment. A modified version of the QuEChERS method has been developed for quantifying eight pharmaceuticals belonging to different classes in three real soils with different chemical properties. Firstly, the soils have been polluted with all contaminants and the recoveries were determined by liquid chromatography tandem–mass spectrometry. Due to similar recoveries from the three soils, the validation of the method has been carried out only on a soil by determining linearity, recovery, precision, limit of detection (LOD) and limit of quantification (LOQ) values. A matrix-matched calibration for the soil has been adopted in order to avoid the matrix effect and three levels of fortification (50, 100 and 500 µg L−1) were used. Results The recovery of all pharmaceuticals, with the exception of tetracycline, from any soil was between 72 and 113%. In the validation procedure, recoveries of fortified samples ranged from 80 to 99%, the relative standard deviations ranged between 1.2 and 11.8%, and the LOQ between 20 and 36.9 μg kg−1. Conclusion The results of the present study confirmed the validity of the modified QuEChERS method for the extraction of pharmaceuticals from soils in the range 50–500 μg kg−1. Graphical Abstrac

    A Shared-Control Teleoperation Architecture for Nonprehensile Object Transportation

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    This article proposes a shared-control teleoperation architecture for robot manipulators transporting an object on a tray. Differently from many existing studies about remotely operated robots with firm grasping capabilities, we consider the case in which, in principle, the object can break its contact with the robot end-effector. The proposed shared-control approach automatically regulates the remote robot motion commanded by the user and the end-effector orientation to prevent the object from sliding over the tray. Furthermore, the human operator is provided with haptic cues informing about the discrepancy between the commanded and executed robot motion, which assist the operator throughout the task execution. We carried out trajectory tracking experiments employing an autonomous 7-degree-of-freedom (DoF) manipulator and compared the results obtained using the proposed approach with two different control schemes (i.e., constant tray orientation and no motion adjustment). We also carried out a human-subjects study involving 18 participants in which a 3-DoF haptic device was used to teleoperate the robot linear motion and display haptic cues to the operator. In all experiments, the results clearly show that our control approach outperforms the other solutions in terms of sliding prevention, robustness, commands tracking, and user’s preference

    Potential of native and bioprocessed brewers' spent grains as organic soil amendments

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    IntroductionThe use of novel soil amendments and the exploitation of plant growth-promoting microorganisms are considered promising tools for developing a more sustainable agriculture in times when ensuring high-yield productions with limited resources is essential. MethodsIn this study, the potential of brewers' spent grain (BSG), the major by-product of the brewing industry, as organic soil amendment, was investigated. Bioprocessed BSG, obtained by an enzymatic treatment coupled with fermentation, together with native BSG, were used as amendments in a pot-trial. An integrated analytical approach aimed at assessing the modification of the physicochemical properties of a typical Mediterranean alkaline agricultural soil, and the plant growth-promoting effect on escarole (Cichorium endivia var. Cuartana), was carried out. ResultsThe use of biomasses led to soil organic content and total nitrogen content up to 72 and 42% higher, compared to the unamended soils. Moreover, the lower pH and the higher organic acids content doubled phosphorus availability. Although the number of leaves per plant in escaroles from pots amended with native and bioprocessed BSG did not show any difference compared to plants cultivated on unamended pots, the average fresh weight per escarole head, was higher in pots amended with bioprocessed BSG. DiscussionHence, the results collected so far encourage BSG application for agricultural purpose, while solving the problem of disposing of such abundant side stream.Peer reviewe

    Intermittent theta-burst stimulation rescues dopamine-dependent corticostriatal synaptic plasticity and motor behavior in experimental parkinsonism. Possible role of glial activity.

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    Background: Recent studies support the therapeutic utility of repetitive transcranial magnetic stimulation in Parkinson's disease (PD), whose progression is correlated with loss of corticostriatal long-term potentiation and long-term depression. Glial cell activation is also a feature of PD that is gaining increasing attention in the field because astrocytes play a role in chronic neuroinflammatory responses but are also able to manage dopamine (DA) levels. Methods: Intermittent theta-burst stimulation protocol was applied to study the effect of therapeutic neuromodulation on striatal DA levels measured by means of in vivo microdialysis in 6-hydroxydopamine-hemilesioned rats. Effects on corticostriatal synaptic plasticity were studied through in vitro intracellular and whole-cell patch clamp recordings while stepping test and CatWalk were used to test motor behavior. Immunohistochemical analyses were performed to analyze morphological changes in neurons and glial cells. Results: Acute theta-burst stimulation induced an increase in striatal DA levels in hemiparkinsonian rats, 80 minutes post-treatment, correlated with full recovery of plasticity and amelioration of motor performances. With the same timing, immediate early gene activation was restricted to striatal spiny neurons. Intense astrocytic and microglial responses were also significantly reduced 80 minutes following theta-burst stimulation. Conclusion: Taken together, these results provide a first glimpse on physiological adaptations that occur in the parkinsonian striatum following intermittent theta-burst stimulation and may help to disclose the real potential of this technique in treating PD and preventing DA replacement therapy-associated disturbances

    Iron homeostasis alterations and erectile dysfunction: A new issue in erectile disfunction treatment?

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    To the Editor, Erectile dysfunction (ED) is one of the most prevalent conditions affecting men globally, with significant psychological and social consequences. The prevalence varies across different populations, and it is estimated around 50% in men aged between 40 to 70. The etiology of ED is multifactorial, involving a complex crosstalk between psychological, hormonal, neurogenic, vascular, and structural factors. Recently, the role of iron homeostasis (IH) is emerging. [...

    Understanding Factors Associated With Psychomotor Subtypes of Delirium in Older Inpatients With Dementia

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