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Cinzia Bragato,1 Andrea Persico,1 Guillem Ferreres,2 Tzanko Tzanov,2 Paride Mantecca1 1POLARIS Research Center, Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milan, 20126, Italy; 2Group of Molecular and Industrial Biotechnology, Universitat Politècnica de Catalunya, Terrassa, 08222, SpainCorrespondence: Cinzia Bragato, Piazza della Scienza 1, Milan, 20126, Italy, Tel +39 0264482928,, Email cinzia.bragato@unimib.itPurpose: Lignin is the most abundant source of aromatic biopolymers and has gained interest in industrial and biomedical applications due to the reported biocompatibility and defense provided against bacterial and fungal pathogens, besides antioxidant and UV-blocking properties. Especially in the form of nanoparticles (NPs), lignin may display also antioxidant and anti-inflammatory activities.Methods: To evaluate these characteristics, sonochemically nano-formulated pristine lignin (LigNPs) and enzymatically-phenolated one (PheLigNPs) were used to expose zebrafish embryos, without chorion, at different concentrations. Furthermore, two different zebrafish inflammation models were generated, by injecting Pseudomonas aeruginosa lipopolysaccharide (LPS) and by provoking a wound injury in the embryo caudal fin. The inflammatory process was investigated in both models by qPCR, analyzing the level of genes as il8, il6, il1β, tnfα, nfkbiaa, nfk2, and ccl34a.4, and by the evaluation of neutrophils recruitment, taking advantage of the Sudan Black staining, in the presence or not of LigNPs and PheLigNPs. Finally, the Wnt/β-catenin pathway, related to tissue regeneration, was investigated at the molecular level in embryos wounded and exposed to NPs.Results: The data obtained demonstrated that the lignin-based NPs showed the capacity to induce a positive response during an inflammatory event, increasing the recruitment of cytokines to accelerate their chemotactic function. Moreover, the LigNPs and PheLigNPs have a role in the resolution of wounds, favoring the regeneration process.Conclusion: In this paper, we used zebrafish embryos within 5 days post fertilization (hpf). Despite being an early-stage exemplary, the zebrafish embryos have proven their potential as predicting models. Further long-term experiments in adults will be needed to explore completely the biomedical capabilities of lignin NPs. The results underlined the safety of both NPs tested paved the way for further evaluations to exploit the anti-inflammatory and pro-healing properties of the lignin nanoparticles examined. Keywords: bio-based nanoparticles, zebrafish embryo, inflammation, LPS, wound

In the context of a closed-loop LFT model, an LMI technique is proposed for the synthesis of a static or dynamic antiwindup controller, which can be seen as a nontrivial extension of existing LMI methods for designing a robust filter or feedforward controller. A missile example is given to illustrate the feasibility of the technique. Index Terms--Antiwindup, feedforward, integral quadratic constraint (IQC), linear fractional transformation (LFT), linear matrix inequality (LMI), linear parameter varying (LPV), linear time invariant/varying (LTI/LTV), saturation.

Summary: This paper describes the application of an indirect linear fractional transformation (LFT)–based state‐space adaptive control scheme to a transport aircraft, within the context of the European project REconfiguration of CONtrol in Flight for Integral Global Upset REcovery. The principle of the scheme is to design and validate off‐line a gain‐scheduled controller, depending on the plant parameters to be estimated, and to combine it online with a model estimator, so as to minimize the onboard computational time and complexity. A modal approach, very classical for the design of a flight control law, is used to directly synthesize the static output feedback LFT controller, depending on the control and stability derivatives, ie, the parameters of the linearized aerodynamic state‐space model to be estimated. Since the gain‐scheduled LFT controller online depends on the parameter estimates instead of the true values, its robustness to transient and asymptotic estimation errors needs to be assessed using μ and integral quadratic constraint analysis techniques. A primary concern being an online implementation, a fully recursive frequency‐domain estimation technique is proposed, with a low online computational burden and the capability to track time‐varying parameters. Full nonlinear simulations along a trajectory validate the good performance properties of the combined estimator and gain‐scheduled flight controller. To some extent, minimal guaranteed stability and performance properties of the adaptive scheme can be ensured by switching to a robust controller when the parameter estimates are not reliable enough, thus bypassing the Certainty Equivalence Principle. [ABSTRACT FROM AUTHOR]

Given a set of H ∞ design specifications, the issue is to check whether there exists a controller, whose order is free, which satisfies these specifications. The classical solution, which is based on Youla parametrization and convex closed loop design, is not really satisfactory since it should use an infinite dimensional basis of filters, which cannot be done in practice. Let J * the minimal value of the design objective over such an infinite dimensional basis of filters. A Nevanlinna Pick interpolation method is proposed here to compute lower and upper bounds of J *, by solving the design problem on a finite set of frequencies. Finite-time convergence of the algorithm is proved. [ABSTRACT FROM AUTHOR]