In a Mean Field Game (MFG) each decision maker cares about the cross sectional distribution of the state and the dynamics of the distribution is generated by the agents' optimal decisions. We prove the uniqueness of the equilibrium in a class of MFG where the decision maker controls the state at optimally chosen times. This setup accommodates several problems featuring non-convex adjustment costs, and complements the well known drift-control case studied by Lasry-Lions.
View Article and Find Full Text PDFA large number of recent studies consider a compartmental SIR model to study optimal control policies aimed at containing the diffusion of COVID-19 while minimizing the economic costs of preventive measures. Such problems are non-convex and standard results need not to hold. We use a Dynamic Programming approach and prove some continuity properties of the value function of the associated optimization problem.
View Article and Find Full Text PDFWe study models where prices respond slowly to shocks because firms are rationally inattentive. Producers must pay a cost to observe the determinants of the current profit maximizing price, and hence observe them infrequently. To generate large real effects of monetary shocks in such a model the time between observations must be long and/or highly volatile.
View Article and Find Full Text PDFTraditionally, withdrawal of thyroid hormone has been used to attain the increase in serum TSH concentrations that are believed to optimize the trapping and retention of radioiodine for diagnostic procedures, thyroid remnant ablation and treatment of patients with differentiated thyroid cancer (DTC). However, withdrawal frequently causes clinical hypothyroidism, with resultant cognitive impairment, emotional dysfunction, physical discomfort, health risks in patients who are elderly, frail or have concomitant illness, and impaired quality of life and ability to work. Recombinant human TSH (rhTSH) was developed to provide TSH stimulation without withdrawal of thyroid hormone and the associated morbidity.
View Article and Find Full Text PDFSerum thyroid hormone concentrations increase after radioiodine (RAI) therapy for Graves' disease. This phenomenon has been ascribed to either antithyroid drug withdrawal before RAI therapy or release of preformed thyroid hormones into the bloodstream from the RAI-damaged thyroid. Lithium blocks the release of iodine and thyroid hormones from the thyroid, thus enhancing the effectiveness of RAI therapy.
View Article and Find Full Text PDFThe aim of the study was to assess whether stimulation by recombinant human TSH (rhTSH) may be used in patients with differentiated thyroid carcinoma for postsurgical ablation of thyroid remnants using a 30-mCi standard dose of (131)I during thyroid hormone therapy. The rate of ablation was prospectively compared in three groups of patients consecutively assigned to one of three treatment arms: in the first arm, patients (n = 50) were treated while hypothyroid (HYPO); in the second arm, patients (n = 42) were treated while HYPO and stimulated in addition with rhTSH (HYPO + rhTSH); in the third arm, patients (n = 70) were treated while euthyroid (EU) on thyroid hormone therapy and stimulated with rhTSH (EU + rhTSH). The outcome of thyroid ablation was assessed by conventional HYPO (131)I scan performed in HYPO state 6-10 months after ablation.
View Article and Find Full Text PDFNodular thyroid disease is the most common endocrine disorder. Nonfunctioning thyroid nodules are identified by their low radioiodide uptake compared with the normal extranodular tissue, which, at thyroid scintiscan, produces the typical picture of a cold thyroid nodule. Previous in vitro studies demonstrated that the majority of nonfunctioning thyroid nodules have a specific defect in iodide transport that accounts for their failure to accumulate radioactive iodide in vivo.
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