319 results on '"Picarelli P"'
Search Results
2. Deep Quadratic Hedging
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Gnoatto, Alessandro, Lavagnini, Silvia, and Picarelli, Athena
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Quantitative Finance - Computational Finance ,Mathematics - Numerical Analysis ,Mathematics - Probability ,Quantitative Finance - Mathematical Finance ,93E20, 65M75, 68T07, 60H10 - Abstract
We present a novel computational approach for quadratic hedging in a high-dimensional incomplete market. This covers both mean-variance hedging and local risk minimization. In the first case, the solution is linked to a system of BSDEs, one of which being a backward stochastic Riccati equation (BSRE); in the second case, the solution is related to the F\"olmer-Schweizer decomposition and is also linked to a BSDE. We apply (recursively) a deep neural network-based BSDE solver. Thanks to this approach, we solve high-dimensional quadratic hedging problems, providing the entire hedging strategies paths, which, in alternative, would require to solve high dimensional PDEs. We test our approach with a classical Heston model and with a multi-dimensional generalization of it., Comment: 43 pages
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- 2022
3. A deep solver for BSDEs with jumps
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Andersson, Kristoffer, Gnoatto, Alessandro, Patacca, Marco, and Picarelli, Athena
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Mathematics - Probability ,Mathematics - Numerical Analysis ,Mathematics - Optimization and Control ,Quantitative Finance - Computational Finance ,Quantitative Finance - Pricing of Securities ,93E20, 65M75, 68T07, 60H10 - Abstract
The aim of this work is to propose an extension of the deep solver by Han, Jentzen, E (2018) to the case of forward backward stochastic differential equations (FBSDEs) with jumps. As in the aforementioned solver, starting from a discretized version of the FBSDE and parametrizing the (high dimensional) control processes by means of a family of artificial neural networks (ANNs), the FBSDE is viewed as a model-based reinforcement learning problem and the ANN parameters are fitted so as to minimize a prescribed loss function. We take into account both finite and infinite jump activity by introducing, in the latter case, an approximation with finitely many jumps of the forward process. We successfully apply our algorithm to option pricing problems in low and high dimension and discuss the applicability in the context of counterparty credit risk., Comment: 33 pages. Update of the algorithm
- Published
- 2022
4. The impact of resveratrol on the outcome of the in vitro fertilization: an exploratory randomized placebo-controlled trial
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A. Conforti, G. G. Iorio, R. Di Girolamo, M. Y. Rovetto, S. Picarelli, F. Cariati, R. Gentile, A. D’Amato, O. Gliozheni, B. Fioretti, and C. Alviggi
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Ovarian sensitivity ,FORT ,FOI ,FSH ,POSEIDON ,Hypo-response ,Gynecology and obstetrics ,RG1-991 - Abstract
Abstract Background Resveratrol is a natural polyphenolic compound present in plants and red wine with many potential health benefits. This compound has various anti-inflammatory and anti-tumor properties and can improve cellular mitochondrial activity. This trial was designed to evaluate the effect on the outcome of IVF of Resveratrol supplementation in women > 35 years with good ovarian reserve (AMH > 1.2 ng/ml). Women were randomized to receive or placebo or Resveratrol (150 mg per day) for three months preceding the ovarian stimulation (OS). All patients were stimulated with a starting dose of recombinant FSH ranging between 150 and 300 IU according to age and ovarian reserve. GnRH antagonist flexible protocol was adopted for pituitary suppression. Triggering was performed with urinary hCG (10.000 IU). Results The study was conducted between January 2019 and December 2022 with aa total of 37 cases and 33 controls were recruited. No statistically significant differences in the number of oocytes retrieved, biochemical pregnancy, clinical pregnancy and live birth rates were observed between women treated with resveratrol and control group. A statistically significant increase in the follicle output rate (FORT) and follicle-to oocyte index (FOI) was observed in women treated with resveratrol-based nutraceutical (0.92 versus 0.77 [p = 0.02], and 0.77 versus 0.64 [p = 0.006], respectively). Conclusions Preliminary results from this study indicate that pre-treatment with resveratrol may improve ovarian sensitivity to exogenous FSH, which in turn may decrease the risk of hypo-response to OS in advanced reproductive age women.
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- 2024
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5. The Red Flysch Formation in Southern Apennines: Lithological and Structural Features and Challenges in Geotechnical Characterization and Modelling
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d’Onofrio, A., Picarelli, L., Santo, A., and Urciuoli, G.
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- 2023
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6. Athlete’s ECG Made Easy: A Practical Guide to Surviving Everyday Clinical Practice
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Valerio Fanale, Andrea Segreti, Chiara Fossati, Giuseppe Di Gioia, Federica Coletti, Simone Pasquale Crispino, Francesco Picarelli, Raffaele Antonelli Incalzi, Rocco Papalia, Fabio Pigozzi, and Francesco Grigioni
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Athlete ,Athlete’s heart ,ECG pattern ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Electrocardiogram modifications in athletes are common and usually reflect structural and electrical heart adaptations to regular physical training, known as the athlete’s heart. However, these electrical modifications sometimes overlap with electrocardiogram findings that are characteristic of various heart diseases. A missed or incorrect diagnosis can significantly impact a young athlete’s life and potentially have fatal consequences during exercise, such as sudden cardiac death, which is the leading cause of death in athletes. Therefore, it is crucial to correctly distinguish between expected exercise-related electrocardiogram changes in an athlete and several electrocardiogram abnormalities that may indicate underlying heart disease. This review aims to serve as a practical guide for cardiologists and sports clinicians, helping to define normal and physiology-induced electrocardiogram findings from those borderlines or pathological, and indicating when further investigations are necessary. Therefore, the possible athlete’s electrocardiogram findings, including rhythm or myocardial adaptation, will be analyzed here, focusing mainly on the differentiation from pathological findings.
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- 2024
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7. On the set of robust sustainable thresholds for uncertain control systems
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Gajardo, Pedro, Hermosilla, Cristopher, and Picarelli, Athena
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Mathematics - Optimization and Control ,Mathematics - Dynamical Systems - Abstract
In natural resource management, or more generally in the study of sustainability issues, often the objective is to maintain the state of a given system within a desirable configuration, typically established in terms of standards or thresholds. For instance, in fisheries management, the procedure of designing policies may include keeping the spawning stock biomass over a critical threshold and also ensuring minimal catches. Given a controlled dynamical system in discrete-time, representing the evolution of some natural resources under the action of controls and uncertainties, and an initial endowment of the resources, the aim of this paper is to characterize the set of robust sustainable thresholds, that is, the thresholds for which there exists some control path, along with its corresponding state trajectory, satisfying for all possible uncertainty scenarios, prescribed mixed constraints parametrized by such thresholds. This set provides useful information to users and decision-makers, illustrating the trade-offs between constraints and it is strongly related to the robust viability, one of the key concepts in viability theory, discipline that study the consistency between a controlled dynamical system and given constraints. Specifically, we are concerned with characterizing the weak and strong Pareto fronts of the set of robust sustainable thresholds, providing a practical method for computing such objects based on optimal control theory and a level-set approach. A numerical example, relying on renewable resource management, is shown to demonstrate the proposed method.
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- 2021
8. Life Cycle Assessment of Electricity Production from Different Biomass Sources in Italy
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Amalia Zucaro, Giuliana Ansanelli, Antonietta Cerbone, Antonio Picarelli, Caterina Rinaldi, Tiziana Beltrani, Silvia Sbaffoni, and Gabriella Fiorentino
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environmental impacts ,Italian LCA database ,bioenergy ,electricity mix ,biogas ,solid biomass ,Technology - Abstract
The European Union is targeting climate neutrality by 2050, with a focus on enhancing energy efficiency, expanding renewable energy sources, and reducing emissions. Within Italy’s electricity mix, bioenergy sources, namely biogas, solid biomass, and bioliquids, play a crucial territorial role. A comparative analysis was conducted through Life Cycle Assessment (LCA), utilizing national data from the ARCADIA project, to assess the environmental sustainability of the investigated bioenergy chains and identify the most convenient ones. The study revealed that, among the bioenergy sources, solid biomass emerges as the most environmentally friendly option since it does not rely on dedicated crops. Conversely, biogas shows the highest environmental impact, demonstrating less favorable performance across nine out of the sixteen evaluated impact categories. The LCA underscores that the cultivation of dedicated energy crops significantly contributes to environmental burdens associated with electricity generation, affecting both biogas and bioliquids performance. The cultivation process needs water and chemical fertilizers, leading to adverse environmental effects. These findings highlight the importance of prioritizing residual biomass for energy generation over dedicated crops. Utilizing forestry and agro-industrial residues, municipal solid waste, and used cooking oils presents numerous advantages, including environmental preservation, resource conservation and recovery, as well as waste reduction.
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- 2024
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9. Deep xVA solver -- A neural network based counterparty credit risk management framework
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Gnoatto, Alessandro, Picarelli, Athena, and Reisinger, Christoph
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Quantitative Finance - Mathematical Finance ,Quantitative Finance - Computational Finance ,Quantitative Finance - Pricing of Securities ,Quantitative Finance - Risk Management - Abstract
In this paper, we present a novel computational framework for portfolio-wide risk management problems, where the presence of a potentially large number of risk factors makes traditional numerical techniques ineffective. The new method utilises a coupled system of BSDEs for the valuation adjustments (xVA) and solves these by a recursive application of a neural network based BSDE solver. This not only makes the computation of xVA for high-dimensional problems feasible, but also produces hedge ratios and dynamic risk measures for xVA, and allows simulations of the collateral account., Comment: 35 pages. Accepted on SIAM Journal on Financial Mathematics
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- 2020
10. Duality-based a posteriori error estimates for some approximation schemes for optimal investment problems
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Picarelli, Athena and Reisinger, Christoph
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Mathematics - Optimization and Control - Abstract
We consider a Markov chain approximation scheme for utility maximization problems in continuous time, which uses, in turn, a piecewise constant policy approximation, Euler-Maruyama time stepping, and a Gauss-Hermite approximation of the Gaussian increments. The error estimates previously derived in Picarelli and Reisinger (2019) are asymmetric between lower and upper bounds due to the control approximation and improve on known results in the literature in the lower case only. In the present paper, we use duality results to obtain a posteriori upper error bounds which are empirically of the same order as the lower bounds. The theoretical results are confirmed by our numerical tests.
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- 2020
11. Current Perspectives in Liver Transplantation for Perihilar Cholangiocarcinoma
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Francesco Giovinazzo, Marco Maria Pascale, Francesca Cardella, Matteo Picarelli, Serena Molica, Francesca Zotta, Annamaria Martullo, George Clarke, Francesco Frongillo, Antonio Grieco, and Salvatore Agnes
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cholangiocarcinoma ,liver transplantation ,biliary tumour ,review ,bile duct neoplasm ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Cholangiocarcinoma (CCA) encompasses all malignant neoplasms arising from the epithelial cells of the biliary tree. About 40% of CCAs are perihilar, involving the bile ducts distal to the second-order biliary branches and proximal to the cystic duct implant. About two-thirds of pCCAs are considered unresectable at the time of diagnosis or exploration. When resective surgery is deemed unfeasible, liver transplantation (LT) could be an effective alternative. The overall survival rates after LT at 1 and 3 years are 91% and 81%, respectively. The overall five-year survival rate after transplantation is 73% (79% for patients with underlying PSC and 63% for de novo pCCA). Multicenter case series reported a 5-year disease-free survival rate of ~65%. However, different protocols, including neoadjuvant therapy, have been proposed. The scarcity of organ availability represents a crucial limiting factor in recommending LT preferentially in treating pCCA. Living donor transplantations and marginal cadaveric allografts have proven to be exciting options to overcome organ shortage. Management of jaundice and cholangitis is still challenging for these patients and could impact LT listing. Whether to adopt surgical resection or LT as standard-of-care in pCCA is still a matter of debate, and more prospective studies are needed.
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- 2023
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12. A simplified procedure to assess the effects of climate change on landslide hazard in a small area of the Southern Apennines in Italy
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Rianna, Guido, Comegna, Luca, Reder, Alfredo, Urciuoli, Gianfranco, and Picarelli, Luciano
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- 2023
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13. Proactive Islanding of the Power Grid to Mitigate High-Impact Low-Frequency Events
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Biswas, Shuchismita, Bernabeu, Emanuel, and Picarelli, David
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Electrical Engineering and Systems Science - Systems and Control - Abstract
This paper proposes a methodology for enhancing power systems resiliency by proactively splitting an interconnected grid into small self-sustaining islands in preparation for extreme events. The idea is to posture the system so that cascading outages can be bound within affected areas, preventing the propagation of disturbances to the rest of the system. This mitigation strategy will prove especially useful when advance notification of a threat is available but its nature not well understood. In our method, islands are determined using a constrained hierarchical spectral clustering technique. We further check the viability of the resultant islands using steady-state AC power flow. The performance of the approach is illustrated using a detailed PSS/E model of the heavily meshed transmission network operated by PJM Interconnection in the eastern USA. Representative cases from different seasons show that variations in power flow patterns influence island configuration.
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- 2019
14. Optimal management of pumped hydroelectric production with state constrained optimal control
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Picarelli, Athena and Vargiolu, Tiziano
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Mathematics - Optimization and Control ,Quantitative Finance - Mathematical Finance - Abstract
We present a novel technique to solve the problem of managing optimally a pumped hydroelectric storage system. This technique relies on representing the system as a stochastic optimal control problem with state constraints, these latter corresponding to the finite volume of the reservoirs. Following the recent level-set approach presented in O. Bokanowski, A. Picarelli, H. Zidani, "State-constrained stochastic optimal control problems via reachability approach", SIAM J. Control and Optim. 54 (5) (2016), we transform the original constrained problem in an auxiliary unconstrained one in augmented state and control spaces, obtained by introducing an exact penalization of the original state constraints. The latter problem is fully treatable by classical dynamic programming arguments.
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- 2019
15. Improved order 1/4 convergence for piecewise constant policy approximation of stochastic control problems
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Jakobsen, Espen R., Picarelli, Athena, and Reisinger, Christoph
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Mathematics - Probability - Abstract
In N.V. Krylov, Approximating value functions for controlled degenerate diffusion processes by using piece-wise constant policies, Electron. J. Probab., 4(2), 1999, it is proved under standard assumptions that the value functions of controlled diffusion processes can be approximated with order 1/6 error by those with controls which are constant on uniform time intervals. In this note we refine the proof and show that the provable rate can be improved to 1/4, which is optimal in our setting. Moreover, we demonstrate the improvements this implies for error estimates derived by similar techniques for approximation schemes, bringing these in line with the best available results from the PDE literature.
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- 2019
16. Crafting Utopias Through Fashion in Ghana and Senegal
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Enrica Picarelli
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african fashion ,decolonial design ,africanfuturism ,ghana ,senegal ,Fine Arts ,Visual arts ,N1-9211 - Abstract
This article introduces two case studies of ethical fashion from Senegal and Ghana: the Africanfuturist brand Selly Raby Kane, based in Dakar, and the Slum Studio collective operating off Kantamanto Market in Accra. Both engage critically with the global politics of clothing, developing place-sensitive and art-inspired responses informed by decolonial approaches to expressive meaning to the multiple threats engendered by the global fashion system.
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- 2022
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17. Coeliac disease in the COVID-19 pandemic: does HLA have a protective effect?
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N. Greco, A. Meacci, B. Mora, A. Vestri, and A. Picarelli
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human leukocyte antigen (hla) ,autoimmune disease ,coeliac disease ,sars-cov-2 ,covid-19 ,Medicine - Abstract
Background The coronavirus disease 2019 (COVID-19), an acute respiratory disease caused by a novel coronavirus (SARS-CoV-2), is emerging as a worldwide public health emergency. Several scientific contributions reported the potential relevance of human leukocyte antigen (HLA) polymorphism and susceptibility to viruses, such as SARS-CoV. In our study, we examined a population of coeliac subjects presenting the HLA haplotype DQ2 and/or DQ8. Our aim was to evaluate whether HLA DQ2 and/or DQ8 haplotype play a role in SARS-CoV-2-infection. The aim was also to evaluate the difficulty in following the gluten-free diet due to all the adversities produced by the pandemic, such as the food supply disruption, and the difficulties in managing the clinical follow-up. Methods 191 consecutive coeliac patients completed a questionnaire on their current clinical status, psychological effects, and management of the gluten-free diet experienced during the COVID-19 pandemic and questions regarding possible SARS-CoV-2 infection. Results Out of the 191 patients who participated in the study, 42 were full-blown coeliac and 149 were in remission. From the answers provided, 84.8% of patients declared that they no longer consider themselves vulnerable to COVID-19 as they suffer from coeliac disease; 94.2% of patients did not encounter any difficulties in managing the gluten-free diet or in acquiring specific foods and 64.9% of patients in our study underwent diagnostic testing for SARS-CoV-2. Out of this number, 31.5% did so due to contacts with subjects affected by COVID-19, 26.6% for work related reasons, 11.3% due to flu-like symptoms and 30.6% for other reasons. Only 5.8% of the enrolled patients received a diagnosis of COVID-19. Out of all the patients in our population who were diagnosed with COVID-19, 94.8% developed no symptoms and none of them needed hospitalization or intensive care. Conclusion The hypothesis that the HLADQ2 and/or DQ8 haplotype plays a protective role against SARS-CoV-2 infection, as against other viral infections, is intriguingly suggestive.KEY MESSAGES COVID-19 as a public health emergency; SARS-CoV-2 and possible complications in coeliac disease; Role of HLA DQ2 and/or DQ8 in SARS-CoV-2 infection.
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- 2022
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18. The preoperative neutrophil-to-lymphocyte ratio predictive value for survival in patients with brain metastasis
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Helder Picarelli, Vitor Nagai Yamaki, Davi Jorge Fontoura Solla, Iuri Santana Neville, Alexandra Gomes dos Santos, Bruno Spindola Amaral Garcia de Freitas, Calvin Diep, Wellingson Silva Paiva, Manoel Jacobsen Teixeira, and Eberval Gadelha Figueiredo
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Brain Neoplasms ,Survival Analysis ,Biomarkers ,Neoplasias Encefálicas ,Análise de Sobrevida ,Biomarcadores ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Background The neutrophil-to-lymphocyte (NLR), monocyte-to-lymphocyte (MLR), platelet-to-lymphocyte ratio (PLR), and red blood cell distribution width (RDW) have been previously studied as predictors of survival in different malignancies.
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- 2022
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19. A complex slope deformation case—history
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Picarelli, L., Santo, A., Di Crescenzo, G., Vassallo, R., Urciuoli, G., Silvestri, F., and Olivares, L.
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- 2022
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20. Probabilistic error analysis for some approximation schemes to optimal control problems
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Picarelli, Athena and Reisinger, Christoph
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Mathematics - Optimization and Control - Abstract
We introduce a class of numerical schemes for optimal control problems based on a novel Markov chain approximation, which uses, in turn, a piecewise constant policy approximation, Euler-Maruyama time stepping, and a Gauss-Hermite approximation of the Gaussian increments. We provide lower error bounds of order arbitrarily close to 1/2 in time and 1/3 in space for Lipschitz viscosity solutions, coupling probabilistic arguments with regularization techniques as introduced by Krylov. The corresponding order of the upper bounds is 1/4 in time and 1/5 in space. For sufficiently regular solutions, the order is 1 in both time and space for both bounds. Finally, we propose techniques for further improving the accuracy of the individual components of the approximation.
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- 2018
21. A level-set approach for stochastic optimal control problems under controlled-loss constraints
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Bouveret, Geraldine and Picarelli, Athena
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Mathematics - Optimization and Control - Abstract
We study a family of optimal control problems under a set of controlled-loss constraints holding at different deterministic dates. The characterization of the associated value function by a Hamilton-Jacobi-Bellman equation usually calls for additional strong assumptions on the dynamics of the processes involved and the set of constraints. To treat this problem in absence of those assumptions, we first convert it into a state-constrained stochastic target problem and then apply a level-set approach. With this approach, the state constraints can be managed through an exact penalization technique.
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- 2018
22. Stability and convergence of second order backward differentiation schemes for parabolic Hamilton-Jacobi-Bellman equations
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Bokanowski, Olivier, Picarelli, Athena, and Reisinger, Christoph
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Mathematics - Numerical Analysis - Abstract
We study a second order BDF (Backward Differentiation Formula) scheme for the numerical approximation of parabolic HJB (Hamilton-Jacobi-Bellman) equations. The scheme under consideration is implicit, non-monotone, and second order accurate in time and space. The lack of monotonicity prevents the use of well-known convergence results for solutions in the viscosity sense. In this work, we establish rigorous stability results in a general nonlinear setting as well as convergence results for some particular cases with additional regularity assumptions. While most results are presented for one-dimensional, linear parabolic and non-linear HJB equations, some results are also extended to multiple dimensions and to Isaacs equations. Numerical tests are included to validate the method.
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- 2018
23. The “landslides best paper award” 2004–2020
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Picarelli, Luciano, Arbanas, Zeljko, and Sassa, Kyoji
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- 2023
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24. Some regularity and convergence results for parabolic Hamilton-Jacobi-Bellman equations in bounded domains
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Picarelli, Athena, Reisinger, Christoph, and Arto, Julen Rotaetxe
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Mathematics - Numerical Analysis - Abstract
We study the approximation of parabolic Hamilton-Jacobi-Bellman (HJB) equations in bounded domains with strong Dirichlet boundary conditions. We work under the assumption of the existence of a sufficiently regular barrier function for the problem to obtain well-posedness and regularity of a related switching system and the convergence of its components to the HJB equation. In particular, we show existence of a viscosity solution to the switching system by a novel construction of sub- and supersolutions and application of Perron's method. Error bounds for monotone schemes for the HJB equation are then derived from estimates near the boundary, where the standard regularisation procedure for viscosity solutions is not applicable, and are found to be of the same order as known results for the whole space. We deduce error bounds for some common finite difference and truncated semi-Lagrangian schemes.
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- 2017
25. Early discontinuation of DTG/ABC/3TC and BIC/TAF/FTC single-tablet regimens: a real-life multicenter cohort study
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Filippo Lagi, Annarita Botta, Arturo Ciccullo, Chiara Picarelli, Massimiliano Fabbiani, Simona di Giambenedetto, Vanni Borghi, Cristina Mussini, Alessandro Bartoloni, and Gaetana Sterrantino
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dtg/abc/3tc ,bic/taf/ftc ,str ,early discontinuation ,cohort study ,switch ,Infectious and parasitic diseases ,RC109-216 - Abstract
Background: Data regarding the efficacy and tolerability of DTG/ABC/3TC/and BIC/TAF/FTC in switching strategies are still scarce. The rates and reasons of early discontinuation within 24 weeks from the switch to dolutegravir (DTG) or bictegravir (BIC) single-tablet regimens (STRs) were compared. Methods: This is a multicenter cohort study. Persons living with HIV (PLWH) with HIV-1 RNA 60 and having switched from a regimen without ABC. Conclusions: PLWH who received DTG or BIC do not show differences in VF or EDAC rates. However, EDAEs is more frequent with DTG especially in the over-sixties and in those who come from regimens without abacavir.
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- 2021
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26. Debt and Private Investment: Does the EU Suffer from a Debt Overhang?
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Vanlaer, Willem, Picarelli, Mattia, and Marneffe, Wim
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- 2021
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27. High-order filtered schemes for time-dependent second order HJB equations
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Bokanowski, Olivier, Picarelli, Athena, and Reisinger, Christoph
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Mathematics - Numerical Analysis ,Mathematics - Optimization and Control ,65M06, 91G80 - Abstract
In this paper, we present and analyse a class of "filtered" numerical schemes for second order Hamilton-Jacobi-Bellman equations. Our approach follows the ideas introduced in B.D. Froese and A.M. Oberman, Convergent filtered schemes for the Monge-Amp\`ere partial differential equation, SIAM J. Numer. Anal., 51(1):423--444, 2013, and more recently applied by other authors to stationary or time-dependent first order Hamilton-Jacobi equations. For high order approximation schemes (where "high" stands for greater than one), the inevitable loss of monotonicity prevents the use of the classical theoretical results for convergence to viscosity solutions. The work introduces a suitable local modification of these schemes by "filtering" them with a monotone scheme, such that they can be proven convergent and still show an overall high order behaviour for smooth enough solutions. We give theoretical proofs of these claims and illustrate the behaviour with numerical tests from mathematical finance, focussing also on the use of backward difference formulae (BDF) for constructing the high order schemes., Comment: 27 pages, 16 figures, 4 tables
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- 2016
28. Investigating Perampanel Antiepileptic Drug by DFT Calculations and SERS with Custom Spinning Cell
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Nicolò Simone Villa, Chiara Picarelli, Federica Iacoe, Chiara Giuseppina Zanchi, Paolo M. Ossi, Andrea Lucotti, and Matteo Tommasini
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quantitative SERS ,spinning cell ,therapeutic drug monitoring ,noise reduction ,Organic chemistry ,QD241-441 - Abstract
SERS, a clinical practice where medical doctors can monitor the drug concentration in biological fluids, has been proposed as a viable approach to therapeutic drug monitoring (TDM) of the antiepileptic drug Perampanel. The adoption of an acidic environment during the SERS experiments was found to be effective in enhancing the spectroscopic signal. In this work, we combine SERS experiments, conducted with a custom spinning cell in controlled acidic conditions, with DFT calculations aimed at investigating the possible protonated forms of Perampanel. The DFT-simulated Raman spectra of protonated Perampanel accounts for most of the observed SERS signals, thus explaining the effective role of protonation of the analyte. Our results suggest protonation as a viable approach to fostering SERS of alkaline drugs.
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- 2023
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29. Sustainable Luxury in South Africa: The Twyg Platform
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Enrica Picarelli
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slow fashion ,sustainable fashion ,digital fashion studies ,south africa ,ethical luxury ,Fine Arts ,Visual arts ,N1-9211 - Abstract
This article investigates the digitisation of ethical luxury in South Africa, focusing on the case study of the media company Twyg. Twyg’s online platform and social media accounts, particularly Instagram, participate in the production and circulation of a discourse on developmental fashion informed by principles of circularity and respect for diversity. The article discusses the communication strategy that Twyg employs to construct a positive discourse around luxury brands as drivers of a specific South African model of sustainability that pursues quality and craftsmanship, while preserving a local circular economy. The article is based on the author’s interviews with Twyg’s founder, Jackie May, and on cultural analysis of the materials published on the platform and Instagram channel. The discussion on sustainability builds on luxury studies, slow fashion studies, and the current debate on decolonialism, making a contribution to the literature on digital luxury in the global South. In particular, it expands the study of small independent actors, offering a reading that complements the more mainstream focus on big brands and international stakeholders.
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- 2021
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30. The hysteretic response of a shallow pyroclastic deposit
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L. Comegna, E. Damiano, R. Greco, L. Olivares, and L. Picarelli
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Environmental sciences ,GE1-350 ,Geology ,QE1-996.5 - Abstract
In the last decades, in Campania (southern Italy), steep slopes mantled by loose air-fall pyroclastic soils have been the seat of shallow, fast, rainfall-induced landslides. The occurrence of such events has been the result of the combination of critical rainstorms and of unfavourable initial conditions determined by antecedent infiltration, evaporation, and drainage processes. In order to understand the nature of the phenomena at hand and to clarify the role of all influencing factors, an automatic monitoring station has been installed in an area already subject to a recent killer flowslide (December, 1999). The paper reports data collected in 2011 about volumetric water content and suction (used to investigate the soil water retention features) and rainfall depth and temperature (providing the boundary conditions). In particular, the installation at the same depths of tensiometers and time domain reflectometry (TDR) sensors allowed us to recognise the hysteretic nature of the wetting and drying soil response to weather forcing and its influence on the slope stability conditions. The data reported in the paper are freely available at https://doi.org/10.5281/zenodo.4281166 (Comegna et al., 2020).
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- 2021
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31. New Insights and Evidence on 'Food Intolerances': Non-Celiac Gluten Sensitivity and Nickel Allergic Contact Mucositis
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Nicoletta Greco, Annalinda Pisano, Laura Mezzatesta, Marta Pettinelli, Arianna Meacci, Maria Gemma Pignataro, Carla Giordano, and Antonio Picarelli
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irritable bowel syndrome (IBS) ,celiac disease ,food intolerance ,nickel allergy ,allergic contact dermatitis (ACD) ,non-celiac gluten sensitivity (NCGS) ,Nutrition. Foods and food supply ,TX341-641 - Abstract
The clinical examination of patients often includes the observation of the existence of a close relationship between the ingestion of certain foods and the appearance of various symptoms. Until now, the occurrence of these events has been loosely defined as food intolerance. Instead, these conditions should be more properly defined as adverse food reactions (AFRs), which can consist of the presentation of a wide variety of symptoms which are commonly identified as irritable bowel syndrome (IBS). In addition, systemic manifestations such as neurological, dermatological, joint, and respiratory disorders may also occur in affected patients. Although the etiology and pathogenesis of some of them are already known, others, such as non-celiac gluten sensitivity and adverse reactions to nickel-containing foods, are not yet fully defined. The study aimed to evaluate the relationship between the ingestion of some foods and the appearance of some symptoms and clinical improvements and detectable immunohistochemical alterations after a specific exclusion diet. One hundred and six consecutive patients suffering from meteorism, dyspepsia, and nausea following the ingestion of foods containing gluten or nickel were subjected to the GSRS questionnaire which was modified according to the “Salerno experts’ criteria”. All patients underwent detection of IgA antibodies to tissue transglutaminase, oral mucosal patch tests with gluten and nickel (OMPT), and EGDS, including biopsies. Our data show that GSRS and OMPT, the use of APERIO CS2 software, and the endothelial marker CD34 could be suggested as useful tools in the diagnostic procedure of these new pathologies. Larger, multi-center clinical trials could be helpful in defining these emerging clinical problems.
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- 2023
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32. Stability and convergence of second order backward differentiation schemes for parabolic Hamilton–Jacobi–Bellman equations
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Bokanowski, Olivier, Picarelli, Athena, and Reisinger, Christoph
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- 2021
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33. Inflow Aggregation and Run-of-the-River Inflow Energy for Reducing Dimensionality in the Long-Term Generation Scheduling Problem
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Guilherme Luiz Minetto Fredo, Erlon Cristian Finardi, Paulo Vitor Larroyd, and Lucas Borges Picarelli
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Inflow modeling ,hydro production function ,the long-term generation scheduling problem ,stochastic dual dynamic programming ,run-of-the-river inflow energy ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
The long-term generation scheduling (LTGS) problem aims to build an operating policy over a multi-year planning horizon, correlating thermal generation and deficit costs with water storage. The LTGS is modeled as a linear multistage stochastic program, whose state-of-art solution is the stochastic dual dynamic programming (SDDP). One critical challenge is to represent the time-dependency of river inflows accurately. Despite recent advances, modeling simplifications are needed to allow the LTGS computational tractability via SDDP since it is necessary to increase the state space to include the time-dependent variables properly. Thus, most works simplify the hydro production function (HPF) to represent the inflows in detail to overcome this negative aspect. However, the literature lacks this trade-off, i.e., finding a balance between stochastic inflow modeling and HPF representation. Thus, this paper proposes an alternative approach to analyzing this trade-off, using the inflow aggregation and run-of-the-river energy inflow instead of individual inflow in SDDP. The proposed approach drastically reduces the number of state variables in SDDP, allowing a detailed HPF representation in the LTGS. We employ a one-sided confidence interval for expected cost estimation to show that our approach provides better performance than the individualized inflows. The analysis is performed in several large-scale computational instances using a power system with 53 geographically widespread hydro plants. The numerical results demonstrate that inflow aggregation provides, on average, a 4 % reduction on the operating cost, whereas for the run-of-the-river inflow energy, the reduction is, on average, 2 %.
- Published
- 2021
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34. Irritable bowel syndrome with diarrhea: is colonoscopy mandatory? Opportunistic use of colon mucosal organ culture to diagnose celiac disease.
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Picarelli, Antonio, Greco, Nicoletta, Meacci, Arianna, Angelucci, Cecilia, Pontone, Stefano, and Donato, Giuseppe
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- 2024
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35. Atypical Virchow-Robin Spaces Mimicking Cystic Primary Brain Tumor – Clinical Report and Literature Review
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Helder Picarelli, Thales Bhering Nepomuceno, Yuri Casal, Vitor Nagai Yamaki, Manoel Jacobsen Teixeira, and Eberval Gadelha Figueiredo
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virchow-robin space ,enlarged perivascular space ,atypical virchow-robin space ,cystic brain tumor ,Medicine ,Surgery ,RD1-811 - Abstract
The Virchow-Robin spaces (VRSs), which are often incidentally observed in modern structural neuroimaging examinations, are small cystic cavities that usually surround the small arteries and arterioles at the level of basal ganglia, the anterior perforated substance and the thalamic-mesencephalic junction. Typically, they have similar physicochemical characteristics to cerebral spinal fluid (CSF) and there is no contrast enhancement on brain CT and MRI images. Its real meaning is unknown, although some contemporary studies have suggested that it might be related to certain traumatic brain injury or several other central nervous system (CNS) disorders, as degenerative diseases. Occasionally, some wide and atypical VRS may be mistaken for primary cystic brain tumors, especially in the context of large and symptomatic lesions, multiple clustered cysts, cortical lesions and if there is adjacent reactive gliosis. The present paper reports four patients who were affected by atypical VRS mimicking brain tumors that required imaging follow-up or even a biopsy to confirm the diagnosis or to indicate the correct approach. Although it is not so unusual, one of them occurred concomitantly and adjacent to a diffuse glioma (co-deleted 1p19q, WHO-GII).
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- 2020
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36. A Diffuse Leptomeningeal Glioneural Tumor Case Producing Hydrocephalus and Polyradiculopathy
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Helder Picarelli, Thales Bhering Nepomuceno, Renan Ribeiro Ribeiro, Vitor Nagai Yamaki, and Eberval Gadelha Figueiredo
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leptomeningeal glioneuronal tumor ,polyradiculopathy ,hydrocephalus ,oligodendroglial-like leptomeningeal tumor of childhood ,pcv chemotherapy ,Medicine ,Surgery ,RD1-811 - Abstract
The present report describes the case of a male 17-year-old patient who progressively developed a hydrocephalus and polyradiculopathy due to involvement of central nervous system (CNS) by a diffuse leptomeningeal glioneuronal tumor (DLGNT). The tumor had partial remission in response to the treatment with radiotherapy plus procarbazine, lomustine, and vincristine (PCV) chemotherapy, and the patient had improvement in function and pain levels. The current knowledge about DLGNT, including its clinical manifestations, imaging findings, histological characteristics, and treatment are revised and discussed in the present paper.
- Published
- 2020
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37. Technical note: The beneficial role of a natural permeable layer in slope stabilization by drainage trenches
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G. Urciuoli, L. Comegna, M. Pirone, and L. Picarelli
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Technology ,Environmental technology. Sanitary engineering ,TD1-1066 ,Geography. Anthropology. Recreation ,Environmental sciences ,GE1-350 - Abstract
Slope stabilization through drainage trenches is a classic approach in geotechnical engineering. Considering the low hydraulic conductivity of the soils in which this measure is usually adopted, a major constraint to the use of trenches is the time required to obtain a significant pore pressure decrease, here called time lag. In fact, especially when the slope safety factor is small, the use of drainage trenches may be a risky approach due to the probability that slope deformations will damage the system well before it will become fully operative.However, this paper shows that the presence of persistent permeable natural soil layers can provide a significant benefit by increasing drainage efficiency and reducing time lag. As a matter of fact, any permeable layer that is intercepted by trenches may operate as part of the global hydraulic system, reducing the drainage paths.A simplified approach to designing a drainage system that accounts for the presence of a persistent permeable layer is proposed. This approach, which can exploit solutions available in the literature for parallel drainage trenches, has been validated by numerical analyses.
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- 2020
- Full Text
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38. Inflammatory Bowel Diseases and Gut Microbiota
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Yuri Haneishi, Yuma Furuya, Mayu Hasegawa, Antonio Picarelli, Mauro Rossi, and Junki Miyamoto
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inflammatory bowel disease ,gut microbiota ,probiotics ,fecal microbiota transplantation ,immunity ,inflammation ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Inflammatory bowel disease (IBD) is an inflammatory disease of the gastrointestinal tract, the incidence of which has rapidly increased worldwide, especially in developing and Western countries. Recent research has suggested that genetic factors, the environment, microbiota, and immune responses are involved in the pathogenesis; however, the underlying causes of IBD are unclear. Recently, gut microbiota dysbiosis, especially a decrease in the abundance and diversity of specific genera, has been suggested as a trigger for IBD-initiating events. Improving the gut microbiota and identifying the specific bacterial species in IBD are essential for understanding the pathogenesis and treatment of IBD and autoimmune diseases. Here, we review the different aspects of the role played by gut microbiota in the pathogenesis of IBD and provide a theoretical basis for modulating gut microbiota through probiotics, fecal microbiota transplantation, and microbial metabolites.
- Published
- 2023
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39. The effects of extreme precipitations on landslide hazard in the pyroclastic deposits of Campania Region: a review
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Picarelli, L., Olivares, L., Damiano, E., Darban, R., and Santo, A.
- Published
- 2020
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40. Effects of Slope Movements on Soil Structure and Hydrological Response
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Comegna, Luca, Picarelli, Luciano, and Urciuoli, Gianfranco
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- 2020
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41. Circulating Nucleic Acids in Maternal Plasma and Serum in Pregnancy Complications: Are They Really Useful in Clinical Practice? A Systematic Review
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Carbone, Ilma Floriana, Conforti, Alessandro, Picarelli, Silvia, Morano, Danila, Alviggi, Carlo, and Farina, Antonio
- Published
- 2020
- Full Text
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42. Visceral and subcutaneous adipose tissue as markers of local and systemic inflammation: a comparison between celiac and obese patients using MRI
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Picarelli, A., Borghini, R., Marino, M., Casale, R., Di Tola, M., Lubrano, C., Piermattei, A., Gualdi, G., Bella, A., Donato, G., and Masselli, G.
- Published
- 2020
- Full Text
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43. High consumption of Nickel‐containing foods and IBS-like disorders: late events in a gluten-free diet
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Antonio Picarelli, Nicoletta Greco, Flavia Sciuttini, Cristiano Marini, and Arianna Meacci
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Nickel ,Allergic Contact Dermatitis (ACD) ,Allergic Contact Mucositis (ACM) ,Irritable Bowel Syndrome (IBS) ,Celiac disease ,Environmental pollution ,TD172-193.5 ,Environmental sciences ,GE1-350 - Abstract
As reported in the recent literature, Nickel has become an important part of our daily life since the last decades. We can find it in skincare products, occupational exposures and foods. Only recently, research has started to show a link between Nickel and many health disorders, including adverse reactions to food containing nickel. Nowadays, the relationship between nickel-containing foods and well-being is becoming a topic of growing interest in clinical practice and will play an even larger role in the future. The use of foods with a high nickel content, largely present in a gluten free diet, could explain the lack of clinical remission in celiac patients and dispel a diagnosis of refractory celiac disease.
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- 2021
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44. A patchy Dynamic Programming scheme for a class of Hamilton-Jacobi-Bellman equations
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Cacace, Simone, Cristiani, Emiliano, Falcone, Maurizio, and Picarelli, Athena
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Mathematics - Numerical Analysis ,Computer Science - Systems and Control ,Mathematics - Optimization and Control ,65N55, 49L20 - Abstract
In this paper we present a new algorithm for the solution of Hamilton-Jacobi-Bellman equations related to optimal control problems. The key idea is to divide the domain of computation into subdomains which are shaped by the optimal dynamics of the underlying control problem. This can result in a rather complex geometrical subdivision, but it has the advantage that every subdomain is invariant with respect to the optimal dynamics, and then the solution can be computed independently in each subdomain. The features of this dynamics-dependent domain decomposition can be exploited to speed up the computation and for an efficient parallelization, since the classical transmission conditions at the boundaries of the subdomains can be avoided. For their properties, the subdomains are patches in the sense introduced by Ancona and Bressan [ESAIM Control Optim. Calc. Var., 4 (1999), pp. 445-471]. Several examples in two and three dimensions illustrate the properties of the new method.
- Published
- 2011
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45. Long-Term Serological Response to 13-Valent Pneumococcal Conjugate Vaccine Versus 23-Valent Polysaccharide Vaccine in HIV-Infected Adults
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Simone Belmonti, Barbara Rossetti, Sara Modica, Lorenzo Paglicci, Alberto Borghetti, Arturo Ciccullo, Chiara Picarelli, Roberto Cauda, Andrea De Luca, Francesca Montagnani, and Francesca Lombardi
- Subjects
HIV ,PCV13 ,Pneumococcal vaccination ,PPV23 ,Serologic response ,Streptococcus pneumoniae ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Introduction Long-term comparative immunologic response to 13-valent pneumococcal conjugate vaccine (PCV13) versus 23-valent polysaccharide vaccine (PPV23) among HIV-infected adults has not yet been investigated. Methods In this prospective pilot study, we quantified in HIV-positive adults serotype-specific IgG concentrations of the 12 pneumococcal serotypes shared by both vaccines 5 years after vaccination with two doses of PCV13 8 weeks apart (group 1) or one dose of PPV23 (group 2) and compared them with those assessed prior to vaccination (BL) and after 1 year (T1). Comparison of immunogenicity was based on geometric mean concentration (GMC), proportion of individuals with ≥ twofold increase from BL in specific antibody concentration against ≥ 2 serotypes and percentage of individuals with serotype-specific IgG ≥ 0.35 μg/ml, ≥ 1 μg/ml and ≥ individual serotype-specific correlates of protection. Results We included 91 subjects (median CD4+ 650 cells/µl, > 90% with HIV-RNA
- Published
- 2019
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- View/download PDF
46. Selly Raby Kane: Surrealist Designer and Social Innovator
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Enrica Picarelli
- Subjects
selly raby kane ,afropolitanism ,senegal ,african fashion ,surrealism ,Visual arts ,N1-9211 - Abstract
Selly Raby Kane is a renowned Senegalese fashion designer and artist involved in Africa’s booming art and design movement. Kane is an interesting case study to grasp fashion’s involvement in Africa’s current debate surrounding identity and empowerment through innovation. This article discusses Kane’s designs in light of her contribution not only to contemporary approaches to African fashion that emphasize individuality, but also to effecting change through fashion, examining the ways in which she mixes symbols, signs, and techniques of African and international cultures to inscribe Africa, and Senegal in particular, into the global fashionscape.
- Published
- 2019
- Full Text
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47. Improving Reporting of Clinical Studies Using the POSEIDON Criteria: POSORT Guidelines
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Sandro C. Esteves, Alessandro Conforti, Sesh K. Sunkara, Luigi Carbone, Silvia Picarelli, Alberto Vaiarelli, Danilo Cimadomo, Laura Rienzi, Filippo Maria Ubaldi, Fulvio Zullo, Claus Yding Andersen, Raoul Orvieto, Peter Humaidan, and Carlo Alviggi
- Subjects
Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number (POSEIDON) criteria ,ovarian stimulation ,low prognosis ,poor response ,infertility ,assisted reproductive technology ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
The POSEIDON (Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number) criteria were developed to help clinicians identify and classify low-prognosis patients undergoing assisted reproductive technology (ART) and provide guidance for possible therapeutic strategies to overcome infertility. Since its introduction, the number of published studies using the POSEIDON criteria has increased steadily. However, a critical analysis of existing evidence indicates inconsistent and incomplete reporting of critical outcomes. Therefore, we developed guidelines to help researchers improve the quality of reporting in studies applying the POSEIDON criteria. We also discuss the advantages of using the POSEIDON criteria in ART clinical studies and elaborate on possible study designs and critical endpoints. Our ultimate goal is to advance the knowledge concerning the clinical use of the POSEIDON criteria to patients, clinicians, and the infertility community.
- Published
- 2021
- Full Text
- View/download PDF
48. The evidence of surgery delay after viscosupplementation is increasing
- Author
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Gianfranco Gigliucci, Giovanni Iolascon, Biagio Moretti, Umberto Tarantino, Luca Gallelli, Marco Paoletta, Giovanna Picarelli, and Alberto Migliore
- Subjects
viscosupplementation ,osteoarthritis ,hyaluronic acid ,total knee replacement ,Internal medicine ,RC31-1245 - Abstract
Osteoarthritis (OA) is a widespread disease throughout the world and prosthetic replacement is considered an effective and definitive treatment. However, some patients do not want or cannot undergo this type of invasive procedure due to the risk of complications. Besides, this kind of surgery is a very expensive treatment for the healthcare system. Real life studies have shown, with growing evidence, that repeated cycles of intra-articular injections of hyaluronic acid (HA) resulted in a significant reduction in pain symptoms as well as an improvement in joint function. Moreover, an important reduction in analgesics consumption was observed. Some studies have shown a delay of total knee replacement (TKR) for up to 2 years. There is minimal data available about the impact of HA injections on the delay of total hip replacement (THR). This review has also evaluated, in addition to clinical research studies, several papers with data from administrative databases suggesting that viscosupplementation possesses the potential to delay or obviate the need for surgery in patients with knee or hip OA. Further studies are necessary to understand the predictors of response, the diversity of response to different HA products, the appropriate dosage and cyclicity in relation to the radiological and clinical stage of the disease.
- Published
- 2020
- Full Text
- View/download PDF
49. Long-Term Serological Response to 13-Valent Pneumococcal Conjugate Vaccine Versus 23-Valent Polysaccharide Vaccine in HIV-Infected Adults
- Author
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Belmonti, Simone, Rossetti, Barbara, Modica, Sara, Paglicci, Lorenzo, Borghetti, Alberto, Ciccullo, Arturo, Picarelli, Chiara, Cauda, Roberto, De Luca, Andrea, Montagnani, Francesca, and Lombardi, Francesca
- Published
- 2019
- Full Text
- View/download PDF
50. Dealing with Negative Inflows in the Long-Term Hydrothermal Scheduling Problem
- Author
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Paulo Vitor Larroyd, Renata Pedrini, Felipe Beltrán, Gabriel Teixeira, Erlon Cristian Finardi, and Lucas Borges Picarelli
- Subjects
time series model ,river inflow ,hydrothermal scheduling ,SDDP ,Technology - Abstract
The long-term hydrothermal scheduling (LTHS) problem seeks to obtain an operational policy that optimizes water resource management. The most employed strategy to obtain such a policy is stochastic dual dynamic programming (SDDP). The primary source of uncertainty in predominant hydropower systems is the reservoirs inflow, usually a linear time series model (TSM) based on the order-p periodic autoregressive [PAR(p)] model. Although the linear PAR(p) can represent the seasonality and autocorrelation of the inflow datasets, negative inflows may appear during SDDP iterations, leading to water balance infeasibilities in the LTHS problem. Different from other works, the focus of this paper is not avoiding negative inflows but instead dealing with the negative values that cause infeasibilities. Hence, three strategies are discussed: (i) inclusion of a slack variable penalized in the objective function, (ii) negative inflow truncation to zero, and (iii) optimal inflow truncation, among which the latter is a novel approach. The strategies are compared individually and combined. Methodological conditions and evidence of the algorithm convergence are presented. Out-of-sample simulations show that the choice of negative inflow strategy significantly impacts the performance of the resultant operational policy. The combination of strategy (i) and (iii) reduces the expected operation cost by 15%.
- Published
- 2022
- Full Text
- View/download PDF
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