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Le torri costiere della Sardegna nel Mediterraneo: cronotipologie delle strutture murarie
The research focuses on the system of coastal towers in Sardinia, the realization of which spans more than five centuries (XIII-XVIII sec.) and reaches its peak between the sixteenth century and the first half of the seventeenth under the impulse of the Spanish monarchy. The coastal fortification process seems well documented in archival sources thanks to the establishment, starting in 1583, of the Reale Amministrazione delle torri This institution managed the system and produced a copious technical and administrative documentation. This made possible the philological dating of construction phase and historic restorations works referring to several towers.
From this awareness comes the desire to investigate, in reference to these buildings, the structural and material characteristics, with particular emphasis on building techniques with the aim of defining an abacus with chrono-typological value. The choice of subject was also influenced by the awareness of the absence of studies, referring to Sardinia, oriented to the knowledge, documentation and chronological definition of construction praxis adopted for the construction of the masonry structures. So, with the awareness of the influence that Spain exercises in the definition of the architectural types and construction techniques in the countries that were under his dominion (direct or indirect), the ongoing study opened to the comparison between Sardinia and other Mediterranean contexts.
Considering the high number of buildings investigated, the study was structured in homogeneous districts also taking care to safeguard all-embracing perspective that takes into account the specificity of the system. Starting from a systematic investigation in situ, eight representative cases-study were identified, selected from the towers belonging to a precise chronological range (16th-17th centuries). Specifically, the study focused on the following towers: Porto Giunco (Villasimius-Sarrabus Area), Mezza Spiaggia (Cagliari Area), San Macario (Teulada-Chia Area), Capo San Marco (Oristano Area), Ischia Ruggia (Bosa Area), Airadu (Alghero Area ), Trabuccato (Stintino-Asinara Area ) and Isola Rossa (Gallura Area).
The need to ensure a systemic approach to the subject, and then to detect a large number of buildings, determined the decision to integrate the classic relief tools with innovative survey methodologies, based on photogrammetric techniques. This made it possible to acquire, in a short time, a satisfactory number of data related to the volumetric characteristics of the investigated buildings, allowing you to check and sometimes refute the previous typological classifications. At the same time, the processing of the product derived from "photomodeling" process provided a detailed basis on which to conduct analytical studies.
With the objective to evaluate the many aspects of the subject, a multidisciplinary and integrated protocol was adopted: the towers were studied from a historical point of view, architectural and typological, technical and mineral-petrographic favoring a stratigraphic approach tailored to the peculiarities of the topic. Cataloging, georeferencing and insertion into a geographic information system made it possible to establish a multi-layer dynamic comparison and thus to reach a critical synthesis of the results obtained.
This methodological approach has led to interesting results and represents a small advancement in the knowledge of these artifacts. In general, while taking into account the number of persons who commissioned the construction, all the towers analyzed shared the choice of a type of easy to build, with technical and architectural solutions far from modernity that characterized other similar systems. The adoption of these solutions, however, meets the basic military requirements. It is strongly influenced by the scarcity of population and economic resources and the need for shorter construction times. Indeed, a low population density in the island coasts and the constant shortage of financial resources, always aggravated by lack of interest by the central government, justified the adoption of a particularly expensive model.
Similarly, in the realization of masonry structures, the short construction times and lower construction costs represent common imperatives. These aspects have influenced the quality of the mortar, often not optimal, and the choice of the stone material. Also the masonry technique most commonly adopted, a cantieri, was an expression of the same needs. It used the most of the available materials, responding to structural requirements. The systematization of the dimensional data relating to the cantieri revealed the recurrence of certain values such as to identify invariants of great interest for the chronological definition of masonry structures. The texture appears almost always irregular, with extreme heterogeneity in dimensions and morfhology of the stone elements. It was conditioned, as expected, by the level of workability of the material.
The data obtained in the analytical phase converge in the project guidelines, aimed at providing methodological ideas and cultural references useful for restoration works. In addition, the multidisciplinary approach, supported by the integration of technological and innovative technical tools, reveals a spendable methodology in other contexts, and to a larger scale. Finally, the typological classification of a wide repertoire of masonry techniques, referred to a specific chronology can be an important basis of comparison for the dating of contemporary buildings
Colloidal CoFe2O4-based nanoparticles for Magnetic Fluid Hyperthermia
In the field of biomedicine, important issues to address are the early-stage diagnosis and targeted therapies. Since the last two decades, magnetic nanoparticles have been proposed as potentially powerful due to their unique chemical-physical properties. Magnetic nanoparticles can be applied in a wide variety of biomedical fields from the magnetic separation and Magnetic Resonance Imaging (MRI) to drug delivery and Magnetic Fluid Hyperthermia (MFH).1 In particular, MFH is based on the heat released by magnetic nanoparticles subjected to an alternate external magnetic field. Among the different material features affecting the hyperthermic efficiency, the magnetic properties are clearly the most important. Therefore, the optimisation of the magnetic properties, aimed to increase the heating ability and to reduce the magnetic material dose to be inserted in the human body, is still an active research field. In 2013 alone, 682 works have been published in the literature on the topic of magnetic hyperthermia.2
Despite cobalt toxicity, cobalt-containing materials and especially cobalt ferrite nanoparticles have been proposed as promising heat mediators due to its high anisotropy.3–13
In this thesis, the results obtained on two different systems, designed with the idea of studying the effect on the hyperthermic properties of proper tuning of the magnetic properties, are presented. Both the sets of samples are based on cobalt ferrite nanoparticles. The first strategy consists on the substitution of cobalt ions with zinc ones with the aim of tuning the magnetic properties of the system and, at the same time, decrease the toxicity of the material. The second way is on the contrary represented by the coating of cobalt ferrite cores by means of biocompatible or less toxic isostructural phases (i.e. magnetite/maghemite or manganese ferrite)
Clustering analysis using Swarm Intelligence
This thesis is concerned with the application of the swarm intelligence methods in
clustering analysis of datasets. The main objectives of the thesis are
∙ Take the advantage of a novel evolutionary algorithm, called artificial bee colony,
to improve the capability of K-means in finding global optimum clusters in
nonlinear partitional clustering problems.
∙ Consider partitional clustering as an optimization problem and an improved antbased
algorithm, named Opposition-Based API (after the name of Pachycondyla
APIcalis ants), to automatic grouping of large unlabeled datasets.
∙ Define partitional clustering as a multiobjective optimization problem. The
aim is to obtain well-separated, connected, and compact clusters and for this
purpose, two objective functions have been defined based on the concepts of
data connectivity and cohesion. These functions are the core of an efficient
multiobjective particle swarm optimization algorithm, which has been devised
for and applied to automatic grouping of large unlabeled datasets.
For that purpose, this thesis is divided is five main parts:
∙ The first part, including Chapter 1, aims at introducing state of the art of swarm
intelligence based clustering methods.
∙ The second part, including Chapter 2, consists in clustering analysis with combination
of artificial bee colony algorithm and K-means technique.
∙ The third part, including Chapter 3, consists in a presentation of clustering
analysis using opposition-based API algorithm.
∙ The fourth part, including Chapter 4, consists in multiobjective clustering analysis
using particle swarm optimization.
∙ Finally, the fifth part, including Chapter 5, concludes the thesis and addresses
the future directions and the open issues of this research
Terapia genica della β Talassemia mediante editing del DNA
β (HBB) gene, resulting in absence (β0) or deficiency (β+) of β globin chain synthesis. This genetic disorder occurs most frequently in people from Mediterranean countries, such as Italy. In particular, the data indicates that about 12.6% of the Sardinian subjects are carriers of β thalassemia and these are among the highest frequencies of thalassemia genes found in a Caucasian population. In Sardinia, the disease is generally determined by a nonsense mutation at codon 39 (E39X) of exon 2 causing the interruption of β globin synthesis. Patients homozygous with E39X mutation have a severe anemia and require frequent transfusions and iron chelation. The only definitive cure today possible for β chain hemoglobinopathies is the hematopoietic stem cells transplantation, but it is limited by availability of HLA matched donors. However, in the last few years new therapeutic approaches for this genetic disease are taking place. The correction of disease-causing mutation through the technique of Genome-Editing in patient-specific stem cells and subsequent autologous transplantation would be the ideal approach for the treatment of monogenic diseases such as β thalassemia. However, due to difficulties in obtaining sufficient homologous recombination percentages for therapeutic purposes, the aim of my PhD project is to reproduce artificially the HPFH mutations identified in non-coding regions of the β globin cluster, using the system CRISPR/Cas9 associated with NHEJ pathway. In this way, we hope to restore at therapeutic levels the expression of HBG genes and consequently the synthesis of a functional HbF in order to ameliorate the phenotype of β thalassemia
Social Media Geographic Information (SMGI): opportunities for spatial planning and governance
The dissertation concerns the opportunities arising from the use of social media platforms as an information resource for supporting design, analysis and decision-making in spatial planning. The widespread diffusion of Web 2.0 technologies and tools such as geobrowsers, Application Programming Interfaces (API), GPS-enabled mobile devices, and recently Location-Based Social Networks are fostering the production, collection and sharing of georeferenced information by the Internet users, namely Volunteered Geographic Information (VGI) and Social Media Geographic Information (SMGI), which are not only related to measures of the geographical component, but also to user perceptions and opinions on places, localities and daily-routine events.
The wealth of VGI and SMGI freely available through the Internet may affect current practices in regional and urban planning, offering opportunities for real-time monitoring of needs, thoughts and trends of local communities. However, several hurdles related to data accessibility and management, as well as to knowledge extraction are limiting a wider use of SMGI in practice. In the light of the above premises, the research goal is to address the different aspects required for properly using VGI and SMGI within the urban and regional planning domains.
The methodological approach is developed following two main directions. First, the approach builds on the design and development of ad-hoc tools able to deal with the issues regarding the access, management and analysis of SMGI. Second, the dissertation formalizes a novel analytical framework, called SMGI Analytics, which enables the proficient use of this information in different planning scenarios. Several case studies are discussed in order to evaluate the value of both the developed tools and the proposed framework. Then, the SMGI Analytics framework is applied on a case study concerning the municipality of Cagliari in Sardinia (Italy) investigating and characterizing a specific public space.
Finally, the dissertation proposes a critical discussion about the developed tools and instruments’ effectiveness for eliciting knowledge from SMGI. The discussion ends identifying the potentialities of obtained findings to address diverse questions related to spatial planning
Il trattamento neonatale con estradiolo modifica l'espressione e la funzione dei recettori GABAA e la sensibilità allo stress nel ratto adulto
Exposure of female rats to estradiol during the perinatal period affects brain sexual differentiation and induces a long-lasting dysregulation of the gonadal axis with reduced progesterone secretion, associated with persistent reductions in the cerebrocortical, hypothalamic and plasma concentrations of its metabolite, allopregnanolone. Given that allopregnanolone is a potent positive modulator of GABAA receptor (GABAAR) expression and function, it has been evaluated whether neonatal estradiol treatment affects, during adulthood, GABAAR expression and function in the hippocampus, an area that exhibits the two components, tonic and phasic, of the inhibitory GABAergic transmission. Neonatal estradiol administration to female rats induced a selective reduction in hippocampal allopregnanolone levels in adult animals, associated with increased expression of extrasynaptic α4/δ subunit-containing GABAARs and tonic currents. Moreover, the same treatment altered the expression of synaptic receptors containing α1/α4/γ2 subunits as well as phasic currents. The changes in the expression and function of GABAARs, induced by neonatal estradiol treatment, may not be related to the fluctuations in allopregnanolone concentrations, given that vehicle-treated rats in diestrus 1, which have opposite neurosteroid levels than estradiol-treated rats, show the same functional changes in GABAARs as estradiol-treated rats.
Allopregnanolone plays an important role in hypothalamic-pituitary-adrenal (HPA) homeostasis and in the stress response. Thus, it has been examined whether neonatal exposure to estradiol was associated with altered HPA axis responsiveness and sensitivity to stress in the adulthood. Neonatal estradiol treatment induced a marked increase in brain and plasma allopregnanolone levels following foot-shock stress, an effect not observed in control animals. Moreover, acute stress increased brain and plasma corticosterone levels to a similar extent in vehicle- and estradiol-treated rats, suggesting that the greater sensitivity of estradiol-treated rats to stress might not involve a dysregulation of the HPA axis. Indeed, the dexamethasone suppression test revealed that hypothalamic and plasma corticosterone levels were decreased to a similar extent in both estradiol- and vehicle-treated adult female rats; moreover, expression of hippocampal glucocorticoid and mineralocorticoid receptors, as well as hypothalamic glucocorticoid receptors, did not differ between estradiol- and vehicle-treated adult female rats, suggesting that the increased stress sensitivity in estradiol-treated rats is independent of HPA axis function. Finally, neonatal estradiol treatment induced a greater enhancement in the extracellular concentrations of dopamine in the prefrontal cortex of adult rats exposed to foot-shock stress, an effect that was normalized by restoring allopregnanolone concentrations with progesterone administration.
These results suggest that neonatal exposure to estradiol plays a major role in the regulation of hippocampal allopregnanolone concentrations, expression and function of GABAARs, as well as stress sensitivity during adulthood. The increased expression and function of α4/δ GABAARs in the hippocampus may represent a homeostatic response to counteract the persistent decrease in allopregnanolone levels induced by neonatal treatment. Given that allopregnanolone has been reported to compensate response to stress, the persistent decrease in its concentrations may account for the higher sensitivity to stress observed in neonatal estradiol-treated rats. These enduring changes in GABAAR plasticity and stress sensitivity may be relevant for regulation of neuronal excitability and for the etiology of psychiatric disorders that originate in development and show sex differences in their prevalence
Design of a Multi-biometric Platform, based on physical traits and physiological measures: Face, Iris, Ear, ECG and EEG
Security and safety is one the main concerns both for governments and for private
companies in the last years so raising growing interests and investments in
the area of biometric recognition and video surveillance, especially after the sad
happenings of September 2001. Outlays assessments of the U.S. government for
the years 2001-2005 estimate that the homeland security spending climbed from
100 billion of 2005. In this lapse of
time, new pattern recognition techniques have been developed and, even more
important, new biometric traits have been investigated and refined; besides
the well-known physical and behavioral characteristics, also physiological measures
have been studied, so providing more features to enhance discrimination
capabilities of individuals. This dissertation proposes the design of a multimodal
biometric platform, FAIRY, based on the following biometric traits: ear,
face, iris EEG and ECG signals. In the thesis the modular architecture of the
platform has been presented, together with the results obtained for the solution
to the recognition problems related to the different biometrics and their possible
fusion. Finally, an analysis of the pattern recognition issues concerning the
area of videosurveillance has been discussed
Metabolic studies on the nitrophile yeast Rhodotorula glutinis DSBCA06
Nitrogen is the most abundant element in atmosphere and fundamental component of proteins, nucleic acids and other essential molecules. In the past century the industrial use of nitrogen compounds has grown exponentially causing widespread pollution. Nitrogen pollution has wide-ranging impacts including contributions to global warming, acid rains and eutrophication.
Reduction of nitrogen use in industry and agriculture coupled whit remediation treatments could represent a solution.
To this purpose we isolated from environmental samples a nitrophile strain capable of removing nitrogen compounds efficiently from the medium. Through the molecular characterization, we identified the strain as a Rhodotorula glutinis that we called DSBCA06.
We examined the main metabolic features of the strain, also to determine the best growing conditions. At the same time, the ability of the strain to grow in presence of high nitrite concentrations was assayed, being a relevant feature poorly studied earlierfor other environmental yeasts. The ability of the strain to grow in presence of heavy metal cations was also tested, showing a noticeable tolerance.
The cost of bioremediation treatments is often a problem. One of the way to obviate this is to produce valuable secondary metabolites, capable of positively impact the cost of the processes. In this context the ability of the strain to produce carotenoids, natural molecules with antioxidant properties used for food production, cosmetic and pharmaceutical industry, has been evaluated.
The strain Rhodotorula glutinis DSBCA06 showed interesting features suggesting its possible use in bioremediation or industrials process for production of secondary metabolites such as lipids and carotenoids
L'architettura dell'acciaio in Italia negli anni Trenta. La Società Nazionale delle Officine di Savigliano
The argument of this research is steel architecture in Italy in the 1930s with a focus on the “Società Nazionale Offcine di Savigliano”. The steel building frame follows a sort of parallel development in the field of the modernisation of the construction system, more connected to the research environment, through competitions and experimental projects. The 1930s are particularly meaningful to the history of metallic constructions. In fact, on the one hand it can be traced a lively cultural debate about the steel frame from the pages of reviews such as Casabella; on the other hand those are the years of the “autocracy”, which determined strong limitations to the use of metals in architecture. Although the limited spread of steel structures, this subject is interesting from a technical point of view and with regard to the construction methods innovations, even if many of these projects remained on paper.
The aim of the research is to retrace this part of the Italian construction history, almost completely unexplored yet, focusing on the case of one of the most important Italian company in the field of metallurgy and steel construction: the “Società Nazionale Officine di Savigliano” (national company workshops Savigliano) and specifically on the production during the 1930s. Until now, the research conducted regarding Savigliano focused in particular on the analysis of labour dynamics and on economic and business issues. The studies concerning construction subjects dealt with the first period of the activity and therefore pertain principally infrastructures. However, a very interesting aspect to consider about Savigliano is the research and experimentation aptitude shown during the thirties.
Savigliano gave a great contribution to the renewal of the building trade, especially with regard to the construction industry, having introduced some important technological innovations, for instance the application of the electrical welding to the metal carpentry. What is more, during the 1930s, the company collaborated with some important architects and engineers, such as Fiorini, for the development of the "tensistruttura" (tensile structure), Nervi for the project of a circular hangar but also Sottsass, Melis and Bernocco, Moretti, De Renzi and Libera
Characterization of Rimonabant effects on G protein activity
G protein-coupled receptor (GPCRs) is the largest class of cell-surface receptors, and represents today the target of 40% of the drugs in the pharmaceutical market. In the absence of agonists, many GPCRs have found to exhibit spontaneous activity, which can be blocked by ligands that are referred to as inverse agonists (Milligan, 2003). Cannabinoid CB1 receptor is one of the most abundant GPCR in the central nervous system, and is coupled to Gi/o proteins to inhibit adenylyl cyclase, activate mitogen-activated protein kinase (MAPK), inhibit voltage gated Ca2+ channels and activate inwardly rectifying K+ channels (Howlett et al., 2000; Pertwee, 2010). The first selective and potent CB1 antagonist Rimonabant (also known SR141716A, SR) at high micromolar concentrations behaves as an inverse agonist, i.e. decreases [35S]GTPγS binding in rodent and human cerebral cortex and in Chinese hamster ovary (CHO) cells transfected with CB1 receptors (Rinaldi-Carmona, 1994). However, in vitro and in vivo studies performed using CB1 knockout (KO) and CHO cells not expressing CB1 receptors suggest that inverse agonist activity of SR is CB1 receptor independent (Pertwee, 2005). Several hypotheses have been postulated to explain the inverse agonism of SR, including its action on different receptors (i.e GPCR mainly coupled to Gi/o proteins) and/or its negative modulation of the constitutive activity of CB1 receptors.
Alternatively, SR might explicate these “inverse agonist effect” in a manner receptor-independent acting directly on G protein level. The present study aimed to determine whether the CB1 receptor-independent effects of SR are mediated via GPCRs, in particular GABAB and dopamine D2 receptors, that share the same Gαi/o signaling pathways, or if SR acts directly on G protein subunits. For this purpose we investigated the molecular mechanisms of SR on G protein activity in native and recombinant systems by using different experimental approaches (i.e., GTPγS binding, bioluminescence Resonance Energy Transfer (BRET), electrophysiological recordings). In particular, we first evaluated the effects of SR on basal and agonist-stimulated [35S]GTPγS binding
in systems containing CB1, GABAB and D2 receptor populations (i.e., rat membrane homogenates and CHO stable transfected with GABAB or D2 receptors), and in systems lacking CB1 and GABAB receptors (i.e., CB1- and GABAB-KO mice).
Then, using BRET approach we monitored dissociation between Gαo and Gβγ subunits and their conformational rearrangements before and after GABAB receptors activation. In addition, using the same assay we studied the molecular interaction between D2 receptor and Gαi1 protein subunits (Gαi1-60, Gαi1-91 and Gαi1-121). Next, we evaluated the effects of SR on adenylate cyclase activity, using BRET with the CAMYEL sensor, a recent technique developed to detect the level of cAMP in living cells. Specifically, the inhibitory effect of SR on Gi and Gs protein pathways measuring BRET signal in cells transfected with CAMYEL and GABAB, D2 or D1 receptors was investigated. Finally, whole cell voltage clamp recordings from midbrain dopamine neurons in acute rat brain slices ex vivo were performed to evaluate the effects of SR on baclofen and quinpirole-induced outward K+ current both in wild-type (WT) and CB1-KO mice. In addition, in order to demonstrate that SR induced the inhibition of GIRK channel activity by acting directly on G protein, we use a GPCR-free experimental setup (i.e. whole cell patch clamp experiments were performed in CHO cells transfected with GIRK1/2). The main finding of this study is that SR, at micromolar concentrations, prevented GPCR-G protein signaling through a direct interaction with the G proteins mainly with the subunits αi/o