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Spike-adding structure in fold/hom bursters
No full textSquare-wave or fold/hom bursting is typical of many excitable dynamical systems, such as pancreatic or other endocrine cells. Besides, it is also found in a great variety of fast-slow systems coming from other neural models, chemical reactions, laser dynamics, and so on. We focus on the spike-adding process and its connection with the homoclinic structure of the system. The creation of new fast spikes on a bursting neuron is an important phenomenon as it increases the duty cycle of the neuron. Here we mainly work with the Hindmarsh-Rose neuron model, a prototype of fold/hom bursting, but also with the pancreatic β-cell model, where, as already known from the literature, homoclinic bifurcations play an important role in bursting dynamics. Based on several numerical simulations, we present a theoretical scheme that provides a complete scenario of bifurcations involved in the spike-adding process and their connection with the homoclinic bifurcations on the parametric space. The global scheme explains the different phenomena of the spike-adding processes presented in literature (continuous and chaotic processes after Terman analysis) and moreover, it also indicates where each kind of spike-adding process occurs. Different elements are involved in the theoretical scheme, such as homoclinic isolas, canard orbits, inclination and orbit flip codimension-two bifurcation points and several pencils of period doubling and fold bifurcations, all of them illustrated with different numerical techniques. Some of these bifurcations needed in the process may be not visible on some numerical simulations because the organizing points are in different parametric planes due to the high dimension of the whole parameter space, but their effects are present. Therefore, we introduce a mechanism of the spike-adding process in fold/hom bursters in the whole space of parameters, even if apparently no role is played by the “far-away” homoclinic bifurcations. This fact is illustrated showing how the theoretical scheme provides a theoretical explanation to the different interspike-interval bifurcation diagrams (IBD) that have appeared in the literature for different models.RB and SS have been supported by the Spanish Research projects MTM2015-64095-P, PGC2018-096026-B-I00, the Universidad de Zaragoza-CUD project UZCUD2019-CIE-04 and European Regional Development Fund and Diputación General de Aragón (E24-17R and LMP124-18). SI and LP have been supported by Spanish Research projects MTM2014-56953-P and MTM2017-87697-P. LP has been partially supported by the Gobierno de Asturias project PA-18-PF-BP17-072
MicroRNA expression in bovine raw milk under different production systems
No full textResumen de comunicaciónDifferences in miRNA expression identified in this study show that they can be used as potential markers of milk production systems, although further analysis to confirm and implement this methodology need to be conducted.Contrato de Formación Predoctoral, Programa "Severo Ochoa" de ayudas predoctorales para la investigación y docencia del Principado de Asturias. BP17-049. Organismo financiador: Consejería de Educación y Cultura. Gobierno del Principado de Asturias. Duración: 2019-2021VI International Conference International Mentoring Foundation for the Advancement of Higher Education (IMFAHE)Las diferencias en la expresión de miARN identificadas en este estudio muestran que pueden usarse como marcadores potenciales de los sistemas de producción de leche, aunque es necesario realizar más análisis para confirmar e implementar esta metodología
¿Hildegarde de Bingen contra Federico Barbarroja?: sobre la génesis de la profecía pseudoepígrafa "Vidi ab aquilone"
Get PDFESPAÑOL: Se edita y estudia una profecía pseudoepígrafa atribuida a Hildegarde de Bingen, que comienza con las palabras «Vidi ab aquilone». La obra se inscribe en la recepción de una visión de cinco animales que la visionaria describe en el Scivias (III, 11): de hecho, se basa en la textualidad de la visión original, que el autor anónimo de la profecía reescribe. Ciertos indicios que proceden de la tradición manuscrita permiten situar su origen en la zona austrobávara del Sacro Imperio Romano Germánico, donde pudo haber sido compuesta en el último cuarto del siglo XII (quizás mientras aun vivía Hildegarde) en contra de Federico I Barbarroja. Como es habitual en los vaticinios bajomedievales, se conservan varias versiones, que se editan por separado. / ENGLISH: A pseudoepigraphic prophecy attributed to Hildegard of Bingen, which begins with the words «Vidi ab aquilone», is edited and studied in this article. The work witnesses the reception of a vision of five beasts described in Scivias III, 11: in fact, it is based on the textuality of this vision, which the anonymous author of the prophecy rewrites. Certain indications that come from the manuscript tradition allow us to place its origin in the Austro-Bavarian area of the Holy Roman Empire, where it could have been composed against Frederick I Barbarossa in the last quarter of the 12th century (perhaps while Hildegard was still alive). As usual in medieval vaticinia, there have been preserved several versions, which are here edited separately
Extradoti e gestione patrimoniale: relazioni familiari, dinamiche sociali e progetti economici in Liguria nei secoli XII e XIII
Get PDFITALIANO: Le extradoti sono i beni, di variegata tipologia, che dovrebbero costituire una competenza esclusiva delle donne coniugate. Questo istituto, poco normato e rilevabile assai prima – già nella seconda metà del XII secolo – che in altri contesti territoriali, è constatabile praticamente in tutti i ceti sociali e nell’intero ambito ligure. L’articolo prende in esame il problema della riconoscibilità di questi beni, la loro costituzione, la loro gestione, che si presta a impieghi molto differenziati ai fini delle dinamiche familiari e della mobilità sociale. Si conclude sulla loro traiettoria, specie nel tardo secolo XIII, che li assimila in parte ai paraphernalia di matrice romana, e in parte alla dote, facendoli così tendenzialmente ricadere così sotto il controllo del marito. / ENGLISH: Non-dotal assets can be defined as those different kinds of goods which should be managed directly by married women. The extrados, an institution which was relatively unregulated and attested already in the second half of the twelfth century – much earlier than in other contexts –, can be found in practically all social classes and in the entire Ligurian area. The article examines the problem of recognizing these assets, their constitution, and management, and were often used for the purposes of family dynamics and social mobility. It concludes by discussing the transformation of the extrados, especially in the late thirteenth century, when these kinds of goods began to be assimilated partly to the Roman paraphernalia, and partly to the dowry, and thus started to fall under the husband’s control
Gestione e devoluzione del patrimonio in ambito extraurbano ligure: le donne delle stirpi signorili nei secoli XII e XIII
Get PDFITALIANO: Tra il secolo XII e il XIII le donne delle stirpi signorili del contesto ligure appaiono impegnate, stando alla documentazione per lo più di impronta urbanocentrica pervenuta, quasi solo nella devoluzione del patrimonio familiare. Queste donne si trovano a contribuire alla gestione dell’inarrestabile declino politico delle proprie stirpi, in un décalage accelerato. In qualche caso riescono forse a inserirsi in città o a mediare rispetto ai funzionamenti di una presenza familiare bilocata tra territorio e città. / ENGLISH: Between the twelfth and thirteenth centuries, women from several Ligurian aristocratic families appear to have been engaged, according to the documentation relative mostly to the urban context, almost only in the devolution of family property. These women eventually had to contribute to the management of the inevitable political decline of their lineages, in an accelerated décalage. In some cases, they were perhaps able to settle in the city or to mediate within families which were present in both territory and city
Dante, Remigio de’ Girolami, il sistema angioino: teologia e politica
Get PDFThis article draws a comparison between Dante’s vision and the cultural, political, and propagandistic conception promoted by the Angevins, from the divergences in the interpretation of Aquinas’ doctrine of Justice to the ones regarding the notion of nobility. Dante expressely chooses his meeting with the Angevin Charles Martel (Pd. VIII) to set human free will in opposition to the Angevin vision of virtue as a good inherited from generation to generation: Charles is a virtuous man not because of, but despite being born into a family which denies the authority of Empire, which is to say the only guarantor of the bonum commune