Le elezioni cantonali ticinesi del 2011. Partecipazione e orientamento di voto fra lealtà, defezione, protesta.

Cette étude scientifique, basée sur une enquête post-électorale (N=1285), vise à analyser le cas des élections du gouvernement et du parlement du Canton du Tessin qui se sont déroulées en avril 2011. Celles-ci constituent un vrai tournant dans l'histoire électorale tessinoise. D'un côté, le taux de participation a été le plus bas depuis 1920 ; d'autre part, la Lega dei ticinesi est devenu le premier parti au Conseil d'Etat avec 2 sièges sur 5. Afin d'analyser les représentations du vote, la participation ainsi que la décision de vote (choix du parti, bulletin sans dénomination du parti, déplacement de votes), nous nous sommes inspirés de la triade conceptuelle de A. O. Hirschman (loyauté, défection et prise de parole). Les résultats montrent que ce vote tessinois ne doit pas être interprété exclusivement en termes de déclin de la loyauté (par rapport à l'acte de vote et aux partis traditionnels), comme augmentation de la défection ou "prise de parole". Au contraire, mais comme une articulation complexe de ces phénomènes.

Telesorveglianza delle insufficienze cardiache: nuove tecnologie permigliorare il follow-up?: revisione Cochrane per il medico di famiglia.

Cet article présente les résultats de la revue systématique: Inglis SC, Clark RA, McAlister FA, et al. Structured telephone support or telemonitoring programmes for patients with chronic heart failure. Cochrane Database Systematic Reviews 2010, Issue 8. Art. No.:CD007228. DOI:10.1002/14651858.CD007228.pub2. PMID: 20687083.

Natural selection in a postglacial range expansion: the case of the colour cline in the European barn owl.

Gradients of variation-or clines-have always intrigued biologists. Classically, they have been interpreted as the outcomes of antagonistic interactions between selection and gene flow. Alternatively, clines may also establish neutrally with isolation by distance (IBD) or secondary contact between previously isolated populations. The relative importance of natural selection and these two neutral processes in the establishment of clinal variation can be tested by comparing genetic differentiation at neutral genetic markers and at the studied trait. A third neutral process, surfing of a newly arisen mutation during the colonization of a new habitat, is more difficult to test. Here, we designed a spatially explicit approximate Bayesian computation (ABC) simulation framework to evaluate whether the strong cline in the genetically based reddish coloration observed in the European barn owl (Tyto alba) arose as a by-product of a range expansion or whether selection has to be invoked to explain this colour cline, for which we have previously ruled out the actions of IBD or secondary contact. Using ABC simulations and genetic data on 390 individuals from 20 locations genotyped at 22 microsatellites loci, we first determined how barn owls colonized Europe after the last glaciation. Using these results in new simulations on the evolution of the colour phenotype, and assuming various genetic architectures for the colour trait, we demonstrate that the observed colour cline cannot be due to the surfing of a neutral mutation. Taking advantage of spatially explicit ABC, which proved to be a powerful method to disentangle the respective roles of selection and drift in range expansions, we conclude that the formation of the colour cline observed in the barn owl must be due to natural selection.

Spatial variation in the temporal change of male and female melanic ornamentation in the barn owl.

Because the magnitude of selection can vary between sexes and in space and time, sexually antagonistic selection is difficult to demonstrate. In a Swiss population of barn owls (Tyto alba), a heritable eumelanic colour trait (size of black spots on ventral feathers) was positively selected with respect to yearling survival only in females. It remains unclear whether the absence of negative selection in males is typical in this species. To tackle this issue indirectly, we measured the size of black spots in 1733 skin specimens collected by museums from 1816 to 2001 in seven European countries and in the Middle-East. The temporal change in spot size was sex- and country-specific. In males, spots became smaller particularly in three countries (Middle-East, Italy and Switzerland). In females, the size of spots increased significantly in two countries (UK and Spain) and decreased in two others (Germany and Switzerland). Because migration and phenotypic plasticity cannot explain these results, selection is the most likely cause. The weaker temporal change in spot size in females than males may be because of the combined effect of strong genetic correlation between the sexes and stronger negative selection in males than positive selection in females. We thus suggest that in the barn owl, spot size (or genetically correlated traits) is sexually antagonistically selected and that its pattern of selection may account for the maintenance of its variation and sexual dimorphism.

Origin-related, environmental, sex, and age determinants of immunocompetence, susceptibility to ectoparasites, and disease symptoms in the barn owl

Knowledge of the role of origin-related, environmental, sex, and age factors on host defence mechanisms is important to understand variation in parasite intensity. Because alternative components of parasite defence may be differently sensitive to various factors, they may not necessarily covary. Many components should therefore be considered to tackle the evolution of host-parasite interactions. In a population of barn owls (Tyto alba), we investigated the role of origin-related, environmental (i.e. year, season, nest of rearing, and body condition), sex, and age factors on 12 traits linked to immune responses [humoral immune responses towards sheep red blood cells (SRBC), human serum albumin (HSA) and toxoid toxin TT, T-cell mediated immune response towards the mitogen phytohemagglutinin (PHA)], susceptibility to ectoparasites (number and fecundity of Carnus haemapterus, number of Ixodes ricinus), and disease symptoms (size of the bursa of Fabricius and spleen, proportion of proteins that are immunoglobulins, haematocrit and blood concentration in leucocytes). Cross-fostering experiments allowed us to detect a heritable component of variation in only four out of nine immune and parasitic parameters (i.e. SRBC- and HSA-responses, haematocrit, and number of C. haemapterus). However, because nestlings were not always cross-fostered just after hatching, the finding that 44% of the immune and parasitic parameters were heritable is probably an overestimation. These experiments also showed that five out of these nine parameters were sensitive to the nest environment (i.e. SRBC- and PHA-responses, number of C. haemapterus, haematocrit and blood concentration in leucocytes). Female nestlings were more infested by the blood-sucking fly C. haemapterus than their male nestmates, and their blood was less concentrated in leucocytes. The effect of year, season, age (i.e. reflecting the degree of maturation of the immune system), brood size, position in the within-brood age hierarchy, and body mass strongly differed between the 12 parameters. Different components of host defence mechanisms are therefore not equally heritable and sensitive to environmental, sex, and age factors, potentially explaining why most of these components did not covary.

La fortuna di Luciano nel Rinascimento : il volgarizzamento del manoscritto Vaticano Chigiano L.VI.215 : edizione critica dei volgarizzamenti delle "Storie vere"

Résumé II lavoro verte sui volgarizzamenti quattro-cinquecenteschi di Luciano di Samosata, importante capitolo nella fortuna dell'autore greco, che diede l'avvio a quel vasto fenomeno chiamato "lucianesimo", esteso in Europa fino al XIX sec. In particolare fornisco l'edizione critica e commentata delle Storie vere volgarizzate, contenute nella prima, assai ampia (41 opuscoli), e per molto tempo unica, silloge lucianea in volgare, che ho datato a poco prima del 1480. Essa ci è giunta tramite un unico manoscritto, il Vaticano Chigiano L.VI.215, confezionato a Ferrara per Ercole I d'Este, nonché in almeno otto edizioni veneziane apparse fra il 1525 e il 1551. La princeps, da cui dipendono in vario modo tutte le edizioni successive, è pubblicata da Niccolò Zoppino. I1 ms. e le prime due edizioni (1525; 1527 Bindoni e Pasini) tacciono il nome del traduttore, che compare solo nell'edizione del 1529 (Zoppino): Niccolò Leoniceno (1428-1524), medico umanista e valente grecista, attivo a Ferrara dal 1464 al 1524, studioso e traduttore di Ippocrate e Galeno, editore di Aristotele e volgarizzatore di storici per Ercole d'Este. L'edizione ha richiesto uno studio preliminare sulle numerose traduzioni in latino e in volgare di Luciano, per valutare meglio le modalità della sua fortuna umanistica. Confrontando ms. e stampe, per le Storie vere si hanno due volgarizzamenti totalmente diversi, fin dal titolo: La vera historia nel ms., Le vere narrazioni nelle cinquecentine. Ma per l'ultimo quarto di testo, ms. e stampe in sostanza coincidono. La collazione ha coinvolto anche il testo greco (con gli apparati delle edizioni critiche) e la versione latina dell'umanista umbro Lilio Tifernate (1417/18-1486) risalente al 1439-43 ca., intitolata De veris narrationibus, di cui si hanno almeno tre redazioni d'autore; una quarta è invece dovuta probabilmente a Benedetto Bordon, che la inserì nella sua silloge latina di Luciano del 1494. Ho cosa stabilito che il volgarizzamento del ms. Chigiano, La vera historia, è stato eseguito direttamente dal greco, fatto eccezionale nel panorama delle traduzioni umanistiche, mentre quello a stampa, Le vere narrazioni, deriva dalla redazione Bordon del De veris narrationibus. La diversità dei titoli dipende dalle varianti dei codici greci utilizzati dai traduttori: il Vat. gr. 1323, o una sua copia, è utilizzato sia dal volgarizzatore del Chigiano, sia da Bordon, indipendentemente l'uno dall'altro; il Marc. gr. 434, o una sua copia, dal Tifernate. Il titolo latino mantenuto da Bordon risale al Tifernate. Per quanto riguarda l'attribuzione dei due volgarizzamenti, come già per altri due testi della silloge da me studiati (Lucio 01 Asino e Timone), anche per La vera historia del Chigiano è accettabile il nome di Niccolò Leoniceno, poiché: 1) essa è tradotta direttamente dal greco, correttamente e con buona resa in volgare, 2) Paolo Giovio -che conobbe di persona il Leoniceno -, negli Elogia veris clarorum virorum imaginibus apposita ricorda che i volgarizzamenti di Luciano e di Dione eseguiti dal Leoniceno piacquero molto ad Ercole d'Este, 3) nessuno nella prima metà del sec. XVI rivendica, per sé o per un suo maestro, il volgarizzamento di Luciano. Le vere narrazioni a stampa, tradotte dal latino del Bordon, dopo il 1494 e prima del 1525, per la parte che diverge dalla Vera historia rimangono invece anonime. Dato che si tratta di due volgarizzamenti distinti, ho allestito l'edizione a fronte dei due testi fin dove essi divergono, seguendo per l'uno il ms., per l'altro la princeps; per la parte finale, in cui confluiscono, mi baso invece sul manoscritto e relego in apparato le varianti più vistose della princeps (non è emerso un chiaro rapporto di dipendenza fra i due testimoni). Oltre all'apparato critico con le lezioni rifiutate, fornisco un commento con la giustificazione delle scelte e il confronto con i corrispondenti passi greci e latini.

Corticosterone promotes scramble competition over sibling negotiation in Barn Owl nestlings (Tyto alba)

In species with parental care, siblings compete for access to food resources. Typically, they vocally signal their level of need to each other and to parents, and jostle for the position in the nest where parents deliver food. Although food shortage and social interactions are stressful, little is known about the effect of stress on the way siblings resolve the conflict over how food is shared among them. Because glucocorticoid hormones mediate physiological and behavioral responses to stressors, we tested whether corticosterone, the main glucocorticoid in birds, modulates physical and vocal signaling used by barn owl siblings (Tyto alba) to compete for food. Although corticosterone-implanted (cort-) nestlings and placebo-nestlings were similarly successful to monopolize food, they employed different behavioral strategies. Compared to placebo-nestlings, cort-individuals reduced the rate of vocally communicating with their siblings (but not with their parents) but were positioned closer to the nest-box entrance where parents predictably deliver food. Therefore, corticosterone induced nestlings to increase their effort in physical competition for the best nest position at the expense of investment in sib-sib communication without modifying vocal begging signals directed to parents. This suggests that in the barn owl stress alters nestlings' behavior and corticosterone could mediate the trade-off between scramble competition and vocal sib-sib communication. We conclude that stressful environments may prevent the evolution of sib-sib communication as a way to resolve family conflicts peacefully.