Adaptive control with neural networks-based disturbance observer for a spherical UAV

This paper develops a control scheme for a Spherical Unmanned Aerial Vehicle (UAV) which can be used in complex scenarios where traditional navigation and communications systems would not succeed. The proposed scheme is based on the nonlinear control theory combined with Adaptive Neural-Networks Disturbance Observer (NN-DOB) and controls the attitude and altitude of the UAV in presence of model uncertainties and external disturbances. The NN-DOB can effectively estimate the uncertainties without the knowledge of their bounds and the control system stability is proven using Lyapunov’s stability theorems. Numerical simulation results demonstrate the validity of the proposed method on the UAV under model uncertainties and external disturbances

Glycomimetic Based Approach toward Selective Carbonic Anhydrase Inhibitors

The synthesis of selective inhibitors of human carbonic anhydrases (hCAs) is of paramount importance to avoid side effects derived from undesired interactions with isoforms not involved in the targeted pathology, and this was partially addressed with the introduction of a sugar moiety (the so-called "sugar approach"). Since glycomimetics are considered more selective than the parent sugars in inhibiting carbohydrate-processing enzyme, we explored the possibility of further tuning the selectivity of hCAs inhibitors by combining the sulfonamide moiety with a sugar analogue residue. In particular, we report the synthesis of two novel hCAs inhibitors 2 and 3 which feature the presence of a piperidine iminosugar and an additional carbohydrate moiety derived from levoglucosenone (1), a key intermediate derived from cellulose pyrolysis. Biological assays revealed that iminosugar 2 is a very strong inhibitor of the central nervous system (CNS) abundantly expressed hCA VII (KI of 7.4 nM) and showed a remarkable selectivity profile toward this isoform. Interestingly, the presence of levoglucosenone in glycomimetic 3 imparted a strong inhibitory activity toward the tumor associated hCA IX (KI of 35.9 nM).Fil: Pratesi, Debora. Università degli Studi di Firenze; ItaliaFil: Matassini, Camilla. Università degli Studi di Firenze; ItaliaFil: Goti, Andrea. Università degli Studi di Firenze; ItaliaFil: Angeli, Andrea. Università degli Studi di Firenze; ItaliaFil: Carta, Fabrizio. Università degli Studi di Firenze; ItaliaFil: Supuran, Claudiu T.. Università degli Studi di Firenze; ItaliaFil: Spanevello, Rolando Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Cardona, Francesca. Università degli Studi di Firenze; Itali

Synthesis of Azasugar–Sulfonamide conjugates and their Evaluation as Inhibitors of Carbonic Anhydrases: the Azasugar Approach to Selectivity

AbstractCarbonic Anhydrases (CAs; EC 4.2.1.1) are zinc metalloenzymes which play a pivotal role both in physiological and pathological processes in humans (h). Therefore, modulation of the activity of hCAs represents an appealing target for drug development, which is highly challenging due to the large number of isozymes expressed and the requirement in discovery of selective inhibitors. By following the "sugar approach" and in light of our recent disclosure of two selective hCAs inhibitors based on nitrogen containing glycomimetic–sulfonamide conjugates, twelve new azasugar−benzenesulfonamides have been synthesized. These compounds were prepared by connecting several benzenesulfonamides to a triazole armed azasugar, varying in the chain length and type of linking moiety (ureido, amido or thioureido) to probe their influence on the inhibition profile. The in vitro biological assays highlighted that such structural changes have remarkable effects on the hCAs inhibition profile. Several new compounds behave as selective inhibitors, and four of them are particularly effective on the therapeutically relevant hCAs II and VII isoforms

Prevalence, Characteristics, and Outcomes of COVID-19-Associated Acute Myocarditis

International audienceBACKGROUND: Acute myocarditis (AM) is thought to be a rare cardiovascular complication of COVID-19, although minimal data are available beyond case reports. We aim to report the prevalence, baseline characteristics, in-hospital management, and outcomes for patients with COVID-19-associated AM on the basis of a retrospective cohort from 23 hospitals in the United States and Europe. METHODS: A total of 112 patients with suspected AM from 56 963 hospitalized patients with COVID-19 were evaluated between February 1, 2020, and April 30, 2021. Inclusion criteria were hospitalization for COVID-19 and a diagnosis of AM on the basis of endomyocardial biopsy or increased troponin level plus typical signs of AM on cardiac magnetic resonance imaging. We identified 97 patients with possible AM, and among them, 54 patients with definite/probable AM supported by endomyocardial biopsy in 17 (31.5%) patients or magnetic resonance imaging in 50 (92.6%). We analyzed patient characteristics, treatments, and outcomes among all COVID-19-associated AM. RESULTS: AM prevalence among hospitalized patients with COVID-19 was 2.4 per 1000 hospitalizations considering definite/probable and 4.1 per 1000 considering also possible AM. The median age of definite/probable cases was 38 years, and 38.9% were female. On admission, chest pain and dyspnea were the most frequent symptoms (55.5% and 53.7%, respectively). Thirty-one cases (57.4%) occurred in the absence of COVID-19-associated pneumonia. Twenty-one (38.9%) had a fulminant presentation requiring inotropic support or temporary mechanical circulatory support. The composite of in-hospital mortality or temporary mechanical circulatory support occurred in 20.4%. At 120 days, estimated mortality was 6.6%, 15.1% in patients with associated pneumonia versus 0% in patients without pneumonia (P=0.044). During hospitalization, left ventricular ejection fraction, assessed by echocardiography, improved from a median of 40% on admission to 55% at discharge (n=47; P\textless0.0001) similarly in patients with or without pneumonia. Corticosteroids were frequently administered (55.5%). CONCLUSIONS: AM occurrence is estimated between 2.4 and 4.1 out of 1000 patients hospitalized for COVID-19. The majority of AM occurs in the absence of pneumonia and is often complicated by hemodynamic instability. AM is a rare complication in patients hospitalized for COVID-19, with an outcome that differs on the basis of the presence of concomitant pneumonia