Riviste Online SApienza - R.O.SA - 2 (Sapienza University of Rome)
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Effect of habitat type on the structure of ant forage areas (Hymenoptera: Formicidae)
Full text linkThe purpose of this paper is to study the structure of ant forage areas in urban habitats, semi-urban habitats and natural habitats. The study was conducted in the Ukrainian regions of Crimea (2012 to 2013) and Kyiv and its suburbs (2015 to 2018, 2021 to 2023). We examined 1321 forage trees and 849 colonies of 9 ant species in Kyiv and suburbs; and 413 trees and 141 colonies of 2 ant species in Crimea. The methods we used included transect examination of the trees with ants along a 10 m wide strip, measuring tree sizes (trunk girth) and recording ant species and numbers. Most ant species show a negative relationship between distance from the tree and the number of workers, indicating that the farther from the tree, the less is the number of ants. In natural habitats, higher numbers of ants and greater distances to forage trees are observed compared with urban or semi-urban habitats. Quercus robur, Pinus sylvestris and Acer platanoides were the most visited trees with a total visit frequency of 0.86 of the total number of records. In urban habitats, Lasius niger and Lasius emarginatus controlled an average of one tree each, and Crematogaster subdentata controlled an average of 5.8 trees. In urban habitats (Kyiv and suburbs), more common were colonies of two ant species (L. niger, Formica cinerea). There was no significant correlation between the distance from the nest to the forage tree and the tree size. Ants show different dispersal strategies in different habitat types. In urban habitats, ants settle closer to forage trees and control fewer trees due to limited food resources
New records of Osmoderma eremita in protected relict forests of Piedmont lowlands (NW Italy) (Coleoptera: Scarabaeidae, Cetoniinae)
Full text linkHermit beetle, Osmoderma eremita (Scopoli, 1763), is a priority species listed in Annexes II and IV of the Habitats Directive, closely linked to mature deciduous trees bearing cavities. As required by articles 11 and 17 of the Directive, in 2021 and 2023 the species was monitored in some lowland wooded areas within the Monviso Park (Piedmont, NW Italy). The monitoring was carried out collecting presence/absence data to inspect population status, phenology and sex ratio, using pheromone baited traps to capture adults during both studies, and searching for exoskeletal remains, larvae and cocoons through the wood mould sampling method in 2021. At the end of the second monitoring period, the presence of the target species was first-time established in all study areas, in addition to other protected saproxylic species records. Planting pollarded trees as well as a forest management attentive to microhabitats are suggested, in order to restore suitable habitat for associated saproxylic beetles and preserve this particularly threatened entomofauna
Dynamic optimal asset allocation in a multivariate setting
Full text linkThis article analyzes a portfolio allocation problem to determine how resources should be allocated among several possible investments. Investors aim to maximize the profit of an investment while also considering the risks arising from infrequent events. The global financial crisis, which began with subprime mortgages in the United States, has fundamentally changed the way we invest. As we know, investors want to maximize returns while controlling the risk associated with a particular investment. This behavior must be modeled mathematically using optimal control theory and expected utility maximization. A continuous-time market is considered in a multivariate context in which there exist risky asset classes and a risk-free asset with a constant interest rate. We deviate from the traditional approach by considering co-precision, the inverse of the covariance matrix, as a measure of risk. The optimal weights obtained are proportional (inversely) to the risk measure (volatility). The model is tested on 11 asset classes used by a large company also carrying out a stress test on the jump component to analyze the allocation of the investors’ portfolio in a real context
Francesca Sabatini, Geografia delle aree interne, Guerini Scientifica, 2024, pp. 320.
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Il “Principe repubblicano”. Paolo Sarpi e altri teorici della sovranità (secc. XVI-XVII)
Full text linkThe concept of “Principe repubblicano” (“Republican absolutism” or “Republican principality”, as the case may be) aims to combine republicanism and absolutism and unites many theories on sovereignty elaborated in sixteenthand seventeenth-century Europe by thinkers of various profiles. This idea is in fact a hybrid that reflects the specific characteristics of the political-state context for which it was conceived: the Republics of Venice, Genoa and Holland, Florence (under Cosimo I de’ Medici), England (under James I Stuart). It is an ideology that seeks to overcome such a complex political-institutional turn of events that new and daring political instruments were needed. Thiscollection of contributions is primarily concerned with the most important of these ideological positions: the “Republican absolutism” by Paolo Sarpi (1552-1623), i.e. the Potestà (Della potestà de’ prencipi), an unfinished work, composed around 1610-11. Long thought to have been lost (or never existed), the Potestà came to light again in 2006, through the seventeenth-century copy identified by Nina Cannizzaro among the manuscripts of the Beinecke Library (Yale University). The political and literary issue revolving around Sarpi’s unfinished treatise that Dimensioni e problemi della ricerca storica brings to the attention of readers on the occasion of the fourth centenary of Sarpi’s death is also extremely compelling. This monographic section contributes to illuminate the “Potestà affair”, especially with regard to the problem of its/Sarpi’s possible or very probable legacies. We hope that some of the hypotheses and suggestions formulated in these pages may sooner or later prove useful in unravelling the tangle
Tra Achse e Avalanche: nemici di tutti. L’8 settembre 1943 nelle memorie dei militari italiani in servizio presso l’aeroporto di Pontecagnano
Full text linkThe events of 8 September 1943 have, among the main discriminating factors, geographical location. The Italian soldiers on duty at Pontecagnano airport 372, after the unexpected proclamation of unconditional surrender and being in an area affected by the Anglo-American landing in the Gulf of Salerno, first suffered immediate action from the men of the Wehrmacht and, a few hours later, that of the Allies. They found themselves, therefore, between Achse and Avalanche. The memoirs written by the soldiers of the Italian Air Force working at the airport, compiledì a few days after the events narrated, constitute a point of view from below and account for the fact that, in addition to being in the midst of the fighting, they were disarmed, arrested, looted, wounded and on one occasion beaten by the Germans, who also attempted to deport them, and were equally disarmed, arrested, deprivedof the possibility of transmitting messages and of the means of transport, including an ambulance, by the Anglo-Americans. They were, essentially, enemies of everyone. Responsibilities for such circumstances fall within the overall management of the armistice; however, the episode also clearly indicates a missed opportunity for Italians to take sides and fight alongside the allied forces and create the conditions for a change in the general political situation
La Calabria e i neoborbonici
Full text linkThe essay shows how neo-Bourbon revisionism reinterprets the epopee of the Risorgimento by making it a negative turning point and the main cause of the backwardness, abandonment, emigration, and poverty of Southern Italy. In an era in which the socioeconomic conditions of the south of the peninsula are destabilized and national politics shows some disinterest, the neo-Bourbons promote their vision of history with a renewed appeal. Calabria is a relevant example of this story – it is a place used by revisionists to confirm their bizarre historical views. The article challenges this narrative and some anti-Risorgimento myths
Il “vincolo esterno”. L’Europa e il repubblicanesimo dopo Ugo La Malfa
Full text linkThe essay analyzes the influence that the process of European unification hadon the Italian republican political culture in the 1970s and 1980s. In particular,it focuses on the choice that the leader of the Italian Republican Party (PRI),Ugo La Malfa, made in 1976 to enroll the PRI in the group of European LiberalDemocrats, in view of the first elections to the European Parliament. Thischoice determined the limits within which the political line of his successors,Giovanni Spadolini and Giorgio La Malfa, was defined. This decision was apparentlysecondary, but it proved to be the heaviest and most lasting legacy leftby the old leader for his party
La socialdemocrazia verso l’Europa: rappresentanza sociale e cultura politico-economica
Full text linkThe present text utilizes a cross-disciplinary approach (economic history, institutionalhistory, political theories) and aims at providing a complex and longtermapproach to the interpretation of the sources. The European socialist andworkers’ movement ran into problems when the stagflationary crisis of the1970s began calling the positive nature of unions’ bargaining power into doubt.However, the sources, not to mention some aspects of the history of economictheories, convey that the socialist and workers’ movement was able to foster significantlyinnovative responses. The latter gradually convinced the SPD, whichbetween 1975 and 1982 had mostly resorted to mere anti-inflationary solutions.Those responses were compatible with the twofold nature of a social movementproducing its own distinct recipes, and of an institutional mediator striking abalanced compromise. Since the Maastricht treaty the technocratic demandsrelated to being an institutional mediator have gradually obscured those connectedto the nature of social movement
