1,356,155 research outputs found
On the use of the time-integrals of the output in observer design for nonlinear autonomous systems
No full textThe goal of this article is to show that the observation scheme recently proposed for linear systems by Menini et al. in 2019, achieving good performance in the presence of a high-frequency measurement disturbance, can be adapted to be used for nonlinear autonomous systems. The design is based on the use of the time-integrals of the measured output and requires the availability of a state observer able to provide a rough estimate of the state; the proposed scheme can be then understood as an observer postprocessing algorithm. For the implementation of the proposed scheme, the time-integrals of the output are required to express as functions of the state of the system. Such functions are called directional antiderivatives; in the article, conditions to guarantee their existence and methods for their computation, in closed-form or by approximation, are resumed. The performance of the proposed observation scheme is illustrated through an example
On the structure of *-modules
No full textLet A and B be rings, A a subcategory of Mod-A closed under submodules and containing AA, and B a subcategory of Mod-B closed under direct sums and epimorphic images. Then any equivalence between A and B is represented by a bimodule APB with A=EndPB via the functors --⊗AP and HomB(P,–). This was proved by Menini and A. Orsatti [Rend. Sem. Mat. Univ. Padova 82 (1989), 203--231 (1990); MR1049594 (91h:16026)], and such a module is called a ∗-module. For instance, every quasi-progenerator and every tilting module is a ∗-module. The purpose of this paper is, in the authors' words, "to measure the gaps between the classes of ∗-modules, of quasi-progenerators and of tilting modules''. Among the results in this direction, it is shown that every finitely generated ∗-module over a commutative ring is a quasi-progenerator; and that this is not the case in general
More appendices for paper “Robust trajectory tracking for a class of hybrid systems: an internal model principle approach” by S. Galeani, L. Menini and A. Potini
No full textThe modulation of the ionic selectivity of the light-sensitive current in isolated rods of the tiger salamander.
No full text1. By using the method of Hodgkin, McNaughton & Nunn (1985) for rapidly changing the extracellular medium, we analysed the effect of the organic compound IBMX (3-isobutyl-1-methylxanthine) on the movement of divalent cations through the light-sensitive channels of isolated retinal rods of the tiger salamander. 2. When the rod is treated with 0.5 mM-IBMX it is possible to observe photocurrents larger than 50 pA carried by Ba2+, Sr2+, Ca2+, Mg2+ and Mn2+. Under these conditions Ca2+, Mg2+ and Mn2+ carry photocurrents of similar amplitude, while Ba2+ and Sr2+ usually carry larger photocurrents. 3. The movement of Mn2+ through the light-sensitive channel, which is hardly detected under normal conditions, can also be observed after treating the rod for a few seconds with a solution containing 35 mM[Na+]o and 10(-7) M[Ca2+]o. Under these conditions the photocurrent carried by Mn2+ is fully saturated in the presence of 1 mM-extracellular Mn2+. 4. When the rod is pre-treated with an extracellular solution containing 0.5 mM-IBMX the maximal photocurrent which can be carried by 10 mM [Ca2+]o increases from about 10 pA to approximately 200 pA. In these conditions the half-activation of the Ca2+ current is between 1 and 10 mM, that is 20-50 times higher than in normal conditions (Menini, Rispoli & Torre, 1988). 5. When the rod is pre-treated with an extracellular solution containing 0.5 mM-IBMX the half-activation of the photocurrent which can be carried by Mg2+, Ba2+ and Sr2+ is equivalent to or greater than 10 mM. In the absence of pre-treatment with IBMX the half-activation of the photocurrent carried by Mg2+, Ba2+ and Sr2+ is less than 5 mM. 6. We conclude that the light-sensitive channel can exist in at least two distinct open states. The selectivity of the channel in the first open state is as described in a previous paper (Menini et al. 1988). Mn2+, which is hardly permeable through the light-sensitive channel in the first open state, can move through the light-sensitive channel in the second open state. Ca2+, Mg2+, Ba2+ and Sr2+ permeate more freely through the light-sensitive channel in the second open state, probably because the electrostatic interactions between these ions and the channel are less strong
Gli insediamenti tradizionali delle Alpi. Conservazione e riuso
No full textIl testo presenta un aggiornamento sulle politiche e le tecniche per la conservazione e valorizzazione degli insediamenti tradizionali delle Alpi. Il libro raccoglie 10 esperienze recenti lungo l’intero Arco Alpino italiano, dagli esperimenti di re - insediamento delle valli del Cuneese e dell’Occitania, alla tutela delle costruzioni d’alta quota nella Vallée, dalle questioni di pianificazione ed economica del territorio in discussione sulle Alpi Centrali, alla tutela dei masi della Val Gardena, fino alla geografia dei Tabià delle Dolomiti venete. Un ampio saggio storico di Giacomo Menini introduce la questione degli insediamenti tradizionali, richiamando gli studi prrotoantropologici di inizio Novecento, da Baragiola a Hunziker. Infine, sono presentati tre recenti progetti “esemplari” per il recupero di questo patrimonio fragile e ancora utile
Voce "Ottavio Menini"
No full textProfilo biografico del letterato Ottavio Menini, nel quale è inoltre descritta tutta la sua produzione letteraria, con puntuale indicazioni di fonti manoscritte e a stampa
Curare il teatro. Il Laboratorio Permanente di Nerval Teatro ad Armunia
No full textA partire dal 2007, le attività del Laboratorio Permanente di Maurizio Lupinelli si svolgono alla confluenza di tre distinte realtà: Armunia, la Cooperativa Nuovo Futuro e, naturalmente, la particolare realtà costituita dal lavoro artistico di Lupinelli con Nerval Teatro. La prima ha voluto il Laboratorio e continua a promuoverne gli esiti scenici inserendoli nelle programmazioni del festival Inequilibrio, la seconda segue i percorsi di inclusione sociale degli attori diversamente abili che partecipano all’iniziativa, la terza traspone le possibilità del teatro all’interno d’un contesto che mira a produrre adattamento sociale.
Il Primo Capitolo di questa pubblicazione approfondisce il percorso del Laboratorio Permanente, ospitando accanto ai contributi di Marco Menini, Laura Caretti e Fabrizio Fiaschini, le testimonianze di Maurizio Lupinelli ed Elisa Pol. Il Secondo è dedicato ai partecipanti al Laboratorio. Il Terzo è costituito dagli Atti della Tavola rotonda Curare il teatro che si è tenuta – con interventi di Gerardo Guccini, Maurizio Lupinelli, Marco Menini, Thomas Emmenegger, Antonio Viganò, Caterina Casini, Claudio Ascoli e Massimo Paganelli – durante l’edizione XXI del festival Inequilibrio (Castiglioncello, 2018)
State estimation for the Newton's cradle: A mechanism that is unobservable in absence of impacts
No full textAbstractWe consider a simplified Newton's cradle, which would be unobservable if the non-smooth impacts between the spheres were ignored. Nevertheless, under the assumption that there is an infinite sequence of nonsmooth impacts, it is possible to design an observer that is able to asymptotically estimate all the nonmeasurable state variables, including those that would be unobservable in absence of impacts
Temporal development of cyclic nucleotide-gated and Ca2+ -activated Cl- currents in isolated mouse olfactory sensory neurons
No full textA Ca(2+)-activated Cl(-) current constitutes a large part of the transduction current in olfactory sensory neurons. The binding of odorants to olfactory receptors in the cilia produces an increase in cAMP concentration; Ca(2+) enters into the cilia through CNG channels and activates a Cl(-) current. In intact mouse olfactory sensory neurons little is known about the kinetics of the Ca(2+)-activated Cl(-) current. Here, we directly activated CNG channels by flash photolysis of caged cAMP or 8-Br-cAMP and measured the current response with the whole cell voltage-clamp technique in mouse neurons. We measured multiphasic currents in the rising phase of the response at -50 mV. The current rising phase became monophasic in the absence of extracellular Ca(2+), at +50 mV, or when most of the intracellular Cl(-) was replaced by gluconate to shift the equilibrium potential for Cl(-) to -50 mV. These results show that the second phase of the current in mouse intact neurons is attributed to a Cl(-) current activated by Ca(2+), similarly to previous results on isolated frog cilia. The percentage of the total saturating current carried by Cl(-) was estimated in two ways: 1) by measuring the maximum secondary current and 2) by blocking the Cl(-) channel with niflumic acid. We estimated that in the presence of 1 mM extracellular Ca(2+) and in symmetrical Cl(-) concentrations the Cl(-) component can constitute up to 90% of the total current response. These data show how to unravel the CNG and Ca(2+)-activated Cl(-) component of the current rising phase
FIGURE 4. Stachytarpheta salimenae P.H.Cardoso & Menini. A. Habit. B. Leaf, abaxial view. C in Taxonomic updates in Brazilian Stachytarpheta (Verbenaceae) with atropurpureous to black corollas: Two new species and a new synonym
No full textFIGURE 4. Stachytarpheta salimenae P.H.Cardoso & Menini. A. Habit. B. Leaf, abaxial view. C. Leaf, abaxial surface showing detail of indumentum. D. Leaf, adaxial surface showing detail of indumentum. E. Bract, abaxial surface showing the indument. F. Calyx, showing the indument and lacinia. G. Dissected corolla, showing androecium and internal indumentum. H. Gynoecium. I. Fruit. (R.J.V. Alves 9035). Drawn by Klei Sousa.Published as part of Cardoso, Pedro Henrique, Neto, Luiz Menini, Cabral, Andressa & Trovó, Marcelo, 2021, Taxonomic updates in Brazilian Stachytarpheta (Verbenaceae) with atropurpureous to black corollas: Two new species and a new synonym, pp. 167-178 in Phytotaxa 523 (2) on page 174, DOI: 10.11646/phytotaxa.523.2.4, http://zenodo.org/record/558543
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