Evolution and historical biogeography of the Eastern Atlantic skates

In my thesis, I tested the hypothesis that the diversification of the Eastern Atlantic skate faunas arose through vicariance rather than dispersal, using combined approach of molecular phylogeny reconstruction and zoogeography (namely historical biogeography). This analyses have been carried out independently on four Rajidae genera belonging to two different tribes: Rajini (Raja and Dipturus) and Amblyrajini (Rajella and Leucoraja). These taxa were selected because they displayed high species diversity and richness of endemic species in the Eastern Atlantic and Mediterranean. The verification of this hypothesis was carried out by reconstructing the best phylogenetic relationships among four genera and 26 species (including several endemism) based on mtDNA and nuDNA gene variation and several statistical approaches. Divergence times of taxa have been estimated based on molecular clock and fossil calibration to explain evolutionary patterns in the context of geological framework. Main issues are (i) the evidence that Eastern Atlantic skate evolution and displacement of species diversity occurred from pulsed geographical speciation (i.e. repeated series of parallel and independent speciation events) started in the Late Eocene-Early Miocene and they have occurred prevalently during Miocene; (ii) such relatively ancient origin of diversification has been allowed the sympatric displacement and evolution of several congeneric taxa likely because they have accumulated huge differences in the genomic and physiological/behavioural phenotypic traits; (iii) recently diverged sister species and taxa showed allopatric or parapatric evolution by the presence of oceanographic or hydrogeographical barriers which likely prevent large mixing between parapatric sister species.

Una prospettiva storico-filosofica sull'evoluzione del curricolo di fisica nella scuola: problemi e innovazioni pedagogiche

Negli ultimi vent’anni sono state proposte al livello internazionale alcune analisi dei problemi per le scienze nella scuola e diverse strategie per l’innovazione didattica. Molte ricerche hanno fatto riferimento a una nuova nozione di literacy scientifica, quale sapere fondamentale dell’educazione, indipendente dalle scelte professionali successive alla scuola. L’ipotesi di partenza di questa ricerca sostiene che alcune di queste analisi e l’idea di una nuova literacy scientifica di tipo non-vocazionale mostrino notevoli limiti quando rapportate al contesto italiano. Le specificità di quest’ultimo sono state affrontate, innanzitutto, da un punto di vista comparativo, discutendo alcuni documenti internazionali sull’insegnamento delle scienze. Questo confronto ha messo in luce la difficoltà di ottenere un insieme di evidenze chiare e definitive sui problemi dell’educazione scientifica discussi da questi documenti, in particolare per quanto riguarda i dati sulla crisi delle vocazioni scientifiche e sull’attitudine degli studenti verso le scienze. Le raccomandazioni educative e alcuni progetti curricolari internazionali trovano degli ostacoli decisivi nella scuola superiore italiana anche a causa di specificità istituzionali, come particolari principi di selezione e l’articolazione dei vari indirizzi formativi. Il presente lavoro si è basato soprattutto su una ricostruzione storico-pedagogica del curricolo di fisica, attraverso l’analisi delle linee guida nazionali, dei programmi di studio e di alcuni rappresentativi manuali degli ultimi decenni. Questo esame del curricolo “programmato” ha messo in luce, primo, il carattere accademico della fisica liceale e la sua debole rielaborazione culturale e didattica, secondo, l’impatto di temi e problemi internazionali sui materiali didattici. Tale impatto ha prodotto dei cambiamenti sul piano delle finalità educative e degli strumenti di apprendimento incorporati nei manuali. Nonostante l’evoluzione di queste caratteristiche del curricolo, tuttavia, l’analisi delle conoscenze storico-filosofiche utilizzate dai manuali ha messo in luce la scarsa contestualizzazione culturale della fisica quale uno degli ostacoli principali per l’insegnamento di una scienza più rilevante e formativa.

Assessing the effectiveness of ISO 3382 for evaluating the acoustical quality of italian historical theatres: the case study of the Bonci Theatre

The present study concerns the acoustical characterisation of Italian historical theatres. It moved from the ISO 3382 which provides the guidelines for the measurement of a well established set of room acoustic parameters inside performance spaces. Nevertheless, the peculiarity of Italian historical theatres needs a more specific approach. The Charter of Ferrara goes in this direction, aiming at qualifying the sound field in this kind of halls and the present work pursues the way forward. Trying to understand how the acoustical qualification should be done, the Bonci Theatre in Cesena has been taken as a case study. In September 2012 acoustical measurements were carried out in the theatre, recording monaural e binaural impulse responses at each seat in the hall. The values of the time criteria, energy criteria and psycho-acoustical and spatial criteria have been extracted according to ISO 3382. Statistics were performed and a 3D model of the theatre was realised and tuned. Statistical investigations were carried out on the whole set of measurement positions and on carefully chosen reduced subsets; it turned out that these subsets are representative only of the “average” acoustics of the hall. Normality tests were carried out to verify whether EDT, T30 and C80 could be described with some degree of reliability with a theoretical distribution. Different results, according to the varying assumptions underlying each test, were found. Finally, an attempt was made to correlate the numerical results emerged from the statistical analysis to the perceptual sphere. Looking for “acoustical equivalent areas”, relative difference limens were considered as threshold values. No rule of thumb emerged. Finally, the significance of the usual representation through mean values and standard deviation, which may be meaningful for normal distributed data, was investigated.

Crisi economiche, sostenibilità ambientale e politiche pubbliche: il ruolo del legislatore e della pubblica amministrazione

Il presente lavoro analizza il ruolo ricoperto dal legislatore e dalla pubblica amministrazione rispettivamente nel delineare e attuare politiche pubbliche volte alla promozione di modelli di sviluppo economico caratterizzati da un elevato tasso di sostenibilità ambientale. A tal fine, il lavoro è suddiviso in quattro capitoli. Nel primo capitolo vengono presi in considerazione i principali elementi della teoria generale che costituiscono i piani di lettura del tema trattato. Questa prima fase della ricerca è incentrata, da un lato, sull’analisi (storico-evolutiva) del concetto di ambiente alla luce della prevalente elaborazione giuridica e, dall’altro, sulla formazione del concetto di sviluppo sostenibile, con particolare riguardo alla sua declinazione in chiave ambientale. Nella parte centrale del lavoro, costituita dal secondo e dal terzo capitolo, l’analisi è rivolta a tre settori d’indagine determinanti per l’inquadramento sistematico delle politiche pubbliche del settore: il sistema di rapporti che esiste tra i molteplici soggetti (internazionali, nazionali e locali) coinvolti nella ricerca di soluzioni alla crisi sistemica ambientale; l’individuazione e la definizione dell’insieme dei principi sostanziali che governano il sistema di tutela ambientale e che indirizzano le scelte di policy nel settore; i principali strumenti (giuridici ed economici) di protezione attualmente in vigore. Il quarto ed ultimo capitolo prende in considerazione le politiche relative alle procedure di autorizzazione alla costruzione e all’esercizio degli impianti per la produzione di energia alimentati da fonti energetiche rinnovabili, analizzate quale caso specifico che può essere assunto a paradigma del ruolo ricoperto dal legislatore e dalla pubblica amministrazione nel settore delle politiche di sviluppo sostenibile. L’analisi condotta mostra un elevato tasso di complessità del sistema istituzionale e organizzativo, a cui si aggiungono evidenti limiti di efficienza per quanto riguarda il regime amministrativo delle autorizzazioni introdotto dal legislatore nazionale.

Yoruba nationalist movements, ethnic politics and violence : a creation from historical consciousness and socio-political space in South-western Nigeria /// Arbeitspapiere / Institut für Ethnologie und Afrikastudien ; 105

Since 1900, the Yoruba people of South-western Nigeria have put its ethnic history at work in the construction of its identity in Nigeria. The exercise resulted in the creation of ethno-nationalist movements and the practice of ethnic politics, often expressed through violent attacks on the Nigerian State and some ethnic groups in Nigeria. Relying on mythological attachment to its traditions and subjective creation of cultural pride, the people created a sense of history that established a common interest among different Yoruba sub-groups in form of pan-Yoruba interest which forms the basis for the people’s imagination of nation. Through this, historical consciousness and socio-political space in which Yoruba people are located acted as instrumental forces employed by Yoruba political elites, both at colonial and post-colonial periods to demand for increasing access to political and economic resources in Nigeria. In form of nationalism, nationalist movements and ethnic politics continued in South-western Nigeria since 1900, yet without resulting to actual creation of an independent Yoruba State up to 2009. Through ethnographic data, the part played by history, tradition and modernity is examined in this paper. While it is concluded that ethno-nationalist movement and ethnic politics in Yoruba society are constructive agenda dated back to pre-colonial period, it continues to transform both in structure and function. Thus, Yoruba ethno-nationalist movement and ethnic politics is ambiguous, dynamic and complex, to the extent that it remains a challenge to State actions in Nigeria.

Molecular phylogeny and historical zoogeography of four genera of Eastern Atlantic skates (Rajiformes, Rajidae)

The aim of this study was to reconstruct a solid phylogeny of four genera of the Rajidae family (Chondrichthyans: Batoidea) using a concatenated alignment of mtDNA genes. Then use the resultant tree to estimate divergence time between taxa based on molecular clock and fossil calibration and conduct biogeographic analysis. The intent was to prove that the actual distribution of species of Eastern Atlantic and Mediterranean skates is due to a series of vicariant events. The species considered belongs to two different tribe: Rajini (Raja and Dipturus) and Amblyrajini (Leucoraja and Rajella). The choice of this genera is due to their high presence in the area of interest and to the richness of endemic species. The results show that despite the ancient origin of Rajidae (97 MYA), the Eastern Atlantic and Mediterranean faunas originated more recently, during Middle Miocene-Late Pliocene, after the closure of connection between these areas and the Indo-Pacific ocean (15 MYA). The endemic species of the Mediterranean (Raja asterias, R. radula, R. polystigma and Leucoraja melitensis) originated after the Messinian salinity crisis (7-5 MYA), when the recolonization of the basin occurred, and are still maintained in allopatric distribution by the presence of biogeographic barriers. Moreover from 4 to 2.6 MYA we can observe the formation of sister species for Raja, Leucoraja and Rajella, one of which has a Northern distribution, and the other has a Southern distribution (R. clavata vs R. straeleni, L. wallacei vs L. naevus, R. fyllae vs R. caudaspinosa and R. kukujevi vs R. leopardus + R. barnardi). The Quaternary and present oceanographic discontinuities that occur along the western African continental shelf (e.g., Cape Blanc and the Angola–Benguela Front) might contribute to the maintenance of low or null levels of gene flow between these closely related siblings species. Also sympatric speciation must be invoked to explain the evolution of skates, for example for the division between R. leopardus and R. barnardi. The speciation processes followed a south-to-north pathways for Dipturus and a north-to-south pathways for Raja, Leucoraja and Rajella underling that the evolution of the genera occurred independently. In the end, it is conceivable that the evolutionary pathways of the tribes followed the costal line during the gondwana fragmentation. The results demonstrate that the evolution of this family is characterized by a series of parallel and independent speciation events, strictly correlated to the tectonic movement of continental masses and paleogeographic and paleoclimatic events and so can be explained by a panbiogeographical (vicariance) model.

Development of An Energy Modeling Approach to Analyse Historical Building Performance

In the last years the attentions on the energy efficiency on historical buildings grows, as different research project took place across Europe. The attention on combining, the need of the preservation of the buildings, their value and their characteristic, with the need of the reduction of energy consumption and the improvements of indoor comfort condition, stimulate the discussion of two points of view that are usually in contradiction, buildings engineer and Conservation Institution. The results are surprising because a common field is growing while remains the need of balancing the respective exigencies. From these experience results clear that many questions should be answered also from the building physicist regarding the correct assessment: on the energy consumption of this class of buildings, on the effectiveness of the measures that could be adopted, and much more. This thesis gives a contribution to answer to these questions developing a procedure to analyse the historic building. The procedure gives a guideline of the energy audit for the historical building considering the experimental activities to dial with the uncertainty of the estimation of the energy balance. It offers a procedure to simulate the energy balance of building with a validated dynamic model considering also a calibration procedure to increase the accuracy of the model. An approach of design of energy efficiency measures through an optimization that consider different aspect is also presented. All the process is applied to a real case study to give to the reader a practical understanding.

"Experimental and computational approaches to historical masonry structures: A study in the direction of filling the gap"

The assessment of historical structures is a significant need for the next generations, as historical monuments represent the community’s identity and have an important cultural value to society. Most of historical structures built by using masonry which is one of the oldest and most common construction materials used in the building sector since the ancient time. Also it is considered a complex material, as it is a composition of brick units and mortar, which affects the structural performance of the building by having different mechanical behaviour with respect to different geometry and qualities given by the components.

The influence of infill walls on seismic behavior of a historical building in Shanghai

Seismic assessment and seismic strengthening are the key issues need to be figured out during the process of protection and reusing of historical buildings. In this thesis the seismic behaviors of the hinged steel structure, a typical structure of historical buildings, i.e. hinged steel frames in Shanghai, China, were studied based on experimental investigations and theoretic analysis. How the non-structural members worked with the steel frames was analyzed thoroughly. Firstly, two 1/4 scale hinged steel frames were constructed based on the structural system of Bund 18, a historical building in Shanghai: M1 model without infill walls, M2 model with infill walls, and tested under the horizontal cyclic loads to investigate their seismic behavior. The Shaking Table Test and its results indicated that the seismic behavior of the hinged steel frames could be improved significantly with the help of non-structural members, i.e., surrounding elements outside the hinged steel frames and infilled walls. To specify, the columns are covered with bricks, they consist of I shape formed steel sections and steel plates, which are clenched together. The steel beams are connected to the steel column by steel angle, thus the structure should be considered as a hinged frame. And the infilled wall acted as a compression diagonal strut to withstand the horizontal load, therefore, the seismic capacity and stiffness of the hinged steel frames with infilled walls could be estimated by using the equivalent compression diagonal strut model. A SAP model has been constructed with the objective to perform a dynamic nonlinear analysis. The obtained results were compared with the results obtained from Shaking Table Test. The Test Results have validated that the influence of infill walls on seismic behavior can be estimated by using the equivalent diagonal strut model.