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Selected Famennian (Late Devonian) events (Condroz, Annulata, Hangenberg) in Sardinia and in the Carnic Alps: conodont biostratigraphy, magnetic susceptibility and geochemistry.
Get PDFThe Condroz, the Annulata and the Hangenberg are three events occurred in the Famennian. Causes and consequences are different for each one. The Condroz event is related to a sharp regression associated with an extinction of few ammonoid groups. The Annulata event to a transgression associated with a global spread of the ammonoid Platyclymeniae annulata. The Hangenberg event is a major event, that took place in a complex phase of eustatic variations that affected severely the fauna, and it is considered as one of the biggest extinction in the history of the earth.
A multidisciplinary approach is here provided to investigate the selected events. A biostratigraphic study based on conodonts was carried out to individuate the precise biostratigraphic position when the events occurred. The evolution of the low field magnetic susceptibility and the major elements geochemistry (Al, Si, K and Ti) have been investigated to study the evolution of the detrital input across the events.
Six different section were studied in two different areas of North Gondwana where the Famennian rocks are well exposed. Two sections bearing the Condroz and the Annulata events were studied in the Carnic Alps, four sections containing the three events were studied in the South East of Sardinia.
A detailed biostratigraphic study is here provided from both areas. More than 28 000 conodonts have been collected and discriminated into 101 taxa. Each taxon is described and illustrated. Ten conodont Zones, from the Upper rhenana Zone (Frasnian) to the Lower expansa Zone (Famennian) have been recognized in the Carnic Alps. Nineteen conodont Zones, from the Lower crepida Zone (Famennian) to the Upper duplicata Zone (Tournaisian) have been discriminated in the Sardinian sections.
The three events have been recognized in both areas. As for the Condroz and for the Annulata events, even if there is no change in lithology, the curves obtained by the MS and the major elements tends to show distinctive peaks time-equivalent to the events. In addition, a stratum rich in ammonoids marks the Annulata event in the field.
As for the Hangenberg event, marked in the field by a thin level of black shales, while the curves of the magnetic susceptibility and the major elements show a constant trend immediately before the main event (Hangenberg equivalent shales), in the earliest Carboniferous the magnetic curve shows distinctive fluctuations. These fluctuations are here explained by a phase of oceanic instability after the event. Despite there are no changes in the MS and in the major element data, the fauna is impoverished and seems to be affected by an earlier phase of the main event already in the Lower praesulcata Zone.
The major detrital input in the Carnic Alps sections may indicate a closer distance to the source for the latter respect to the Sardinia-Corsica microplate, therefore a new palaeogeographic interpretation for the two areas investigated in the Upper Devonian is here hypothesize
Caratterizzazione del clofibrato agonista sintetico dei recettori dei proliferatori dei perossisomi (PPARα)in modelli animali di depressione ed ansia
Get PDFDepression is a severe mood disorder that affects a high percentage of the worldwide population. Unfortunately at least 40% of patients do not respond to the treatment. Therefore, considerable effort is invested in the development of alternative therapeutic approaches for the pharmacotherapy of depression. Peroxisome proliferator-activated receptors alpha (PPARα) are widely expressed in the brain and are activated by endogenous ligands like the fatty acid amides N-palmitoylethanolamide (PEA) and oleoylethanolamide (OEA). Recent studies have been published on PPARα mediated behavioral effects, which suggests that PEA exerts anxiolytic and antidepressant-like effect in mice (Crupi et al., 2013, Yu et al., 2011). However no studies have been evaluated antidepressant-like effect of synthetic PPARα agonists. Thus, the aim of our study was to characterize the pharmacological profile of synthetic PPARα agonists as clofibrate by motor activity test to evaluate possible motor impairments, the forced swim test (FST) for the antidepressant activity, the elevated plus maze (EPM) and the social interaction test (SI) for anxiolytic like effects.
The standard antidepressant drugs used in FST (fluoxetine 5mg/kg and amitriptyline 15 mg/kg, i.p) induced a significant increase of the duration of swimming respect to the vehicle-treated control group. Also the sub-chronic treatment with clofibrate (25 mg/kg, i.p) significantly increased swimming time and decreased immobility time in the FST with respect to vehicle-treated control group. We also investigated the possible contribution of PPARα and the endocannabinoid system on antidepressant-like effect induced by clofibrate, fluoxetine and amitriptyline. Acute administration of the specific PPARα antagonist MK886 (1 mg/kg, i.p) or the CB1 antagonist/inverse agonist SR141716A (1 mg/kg, i.p) did no antagonize the antidepressant-like effect induced by classical antidepressant drugs. In contrast the antidepressant-like affects of clofibrate were reverted by the acute administration of specific PPARα antagonist MK886 demonstrating an involvement of PPARα, while, the CB1r antagonist/inverse agonist SR141716A,
conversely MK886, did no antagonize the antidepressant-like effect of clofibrate, excluding a possible involvement of the endocannabinoid system. Interestingly, the co-administration of sub-effective dose of clofibrate (12.5 mg/kg, i.p) and fluoxetine (2 mg/kg, i.p) revealed an increase of swimming and decrease of immobility suggesting a possible interaction between the PPARα receptors and the serotoninergic system. No effect was observed when clofibrate was combined with amitriptyline. Clofibrate and PEA maintain an antidepressant effect also after 14 days of chronic treatment (25 mg/kg, 1 mg/kg, i.p respectively) in the FST.
Moreover, none of the PPARα agonists injected acutely, produced anxiolytic or anxiogenic-like behaviors in the EMP test, while an anxiogenic profile was observed after acute treatment in the SI test, with a reduction of the total time spent in social interactions but an unaltered numbers of contacts. No anxiogenic or anxiolytic effect was observable after chronic treatment with both clofibrate and PEA.
In conclusion, these data show that clofibrate, synthetic PPARα ligand, produces antidepressant-like effect in animals, effect that is specifically mediated via PPARα-activation but that also hypothesizes an interaction with the serotoninergic system since it potentiates the fluoxetine behavioral action. PPARα agonists, that are still prescribed for the treatment of primary hypercholesterolemia, mixed dyslipidemia, and hypertriglyceridemia, it deserve further characterization as a new candidate for the pharmacotherapy of depression
Il nulla, l’essere, la mistica, nella filosofia del giovane Sartre (1933-1943)
Get PDFThis work is dedicated to the study of Jean-Paul Sartre’s earlier philosophy, in the years
between 1933 and 1943, namely between his first philosophical work, The Transcendence of
the Ego, and Being and Nothingness. Its aim is to demonstrate how the suggestions related
to his own studies on speculative mysticism influenced the same philosopher during this
period. The issue about how to reconcile the level of the religious experience of
mysticism with the one of the phenomenological analysis of his early works finds a
solution in Sartre himself: in fact, he justifies his adhesion to phenomenology as the
possibility of speaking about life itself, and for this reason his quasi-religious experience
(an expression coined here in relation to analogous forms used by Sartre) finds the form
of philosophic expression.
The first part of this thesis shows how the stages that Sartre goes examines in his
analysis of human consciousness resemble those which characterize the path of
speculative mysticism (phases of the mystic process are always the same even though
they refer to authors who differ for their historical collocation, nationality and religious
experience). These stages are: 1. The death of the ego; 2. Separation; 3. The emerging of
a will which appears external to the subject; 4. The tendency towards nothingness and
the discovery of the subject as nothingness; 5. The abandonment to be hetero-directed;
6. Freedom as a necessity; 7. The non existence of value; 8. Anguish; 9. The experience
of silence; 10. Apophatic speech; 11. The identification with the absolute (although
Sartre sees it as a failure); 12. The morality of commitment.
In the second chapter the relationship between being and entity in Sartre is analyzed,
thus showing how the Eckartian concept of the relationship between divinity and
creature is put forward again. In particular, the “solution” to the problem suggested by
Sartre mirrors the one which fills, in his mysticism, the abyss between Man and the
Absolute; in fact, only by taking the difference to extremes, for which man becomes
absolutely nothing, God can make him divine; equally in Sartre, the subject, the absolute
nothing, can know the object without modifying it.
In the third chapter M. Eckahrt's mysticism of the image is related to Sartre's
metaphysics of the image, thus demonstrating that Sartre's theses on the nature of the
image derive from speculative mysticism: in fact, the image is not an opaque object, the
degradation of perception, but a way in which the human consciousness presents itself
in its creative activity. Finally, in the Conclusion, the aim is to go beyond the period
1933-43, to see if the search key on mysticism could be suitable for a new possible
interpretation of the entire Sartrian work
Technological cycles, Meta-Ranking and Open Access Performance
Get PDFThis thesis consists of three essays, linked by innovation, classification and
change. In the first paper, I analyze a theoretical problem regarding the reemergence
and affirmation of a technological paradigm over the others; in the
second article, I propose a framework to aggregate journal rankings and classify
academic journals; in the third essay I analyze the performance of Open Access
journals, considered an innovative form of publishing, with the aim of identifying
the main features of top-rated ones.
More specifically, the first essay deals on the technological life cycle which explains
how the battles between competing technologies sooner or later end with
the dominance of one over the others, or, under certain conditions, with their coexistence.
However, the practice points out that, sometimes, beaten technologies
can re-emerge in the market. Firms dealing with technology investment decisions
need to completely understand the competing technologies dynamics, because the
emergence of an alternative and potentially superior technology does not necessarily
mean the failure of the incumbent, and different scenario would be traced.
Starting from the analysis of the microprocessor market and considering the relationships
with complementary companies, I show how the battle for dominance
between two rival technologies can be reopened with a new era of ferment. While
factors of dominance have been explored by a great amount of literature, little has
been said on this question. In particular, I find a non-conventional S-curve trend
and I seek to explicate its managerial implication.The second chapter deals with ranking academic journals, an issue that during
the years received several contribute from literature of Business and Management
[DuBois and Reeb, 2000, Franke et al, 1990, Serenko and Bontis, 2004,
Tüselmann et al, 2015, Werner, 2002]. Ranking journals is a longstanding problem
and can be addressed quantitatively, qualitatively or using a combination of
both approaches. In the last decades, the Impact Factor (i.e., the most known
quantitative approach) has been widely questioned, and other indices have thus
been developed and become popular. Previous studies have reported strengths
and weaknesses of each index, and devised meta-indices to rank journals in a certain
field of study. However, the proposed meta-indices exhibit some intrinsic
limitations: (i) the indices to be combined are not always chosen according to
well-grounded principles; (ii) combination methods are usually unweighted; and
(iii) some of the proposed meta-indices are parametric, which requires assuming
a specific underlying data distribution. I propose a data-driven methodology that
linearly combines an arbitrary number of indices to produce an aggregated ranking,
using different learning techniques to estimate the combining weights. I am
also able to measure correlations and distances between indices and meta-indices
in a vector space, to quantitatively evaluate their differences.
The goal of the third essay, is to identify the features of top-rated gold open
access (OA) journals by testing seven main variables: languages, countries, years
of activity and years in the DOAJ repository, publication fee, the field of study,
whether the journal has been launched as OA or converted, and the type of publisher.
A sample of 1,910 gold OA journals has been obtained by combining
SCImago Journal & Country Rank (SJR) 2012, the DOAJ, and data provided by previous studies [Solomon, 2013]. I have divided the SJR index into quartiles
for all journals' subject areas. First, I show descriptive statistics by combining
quartiles based on their features. Then, after having converted the quartiles into
a dummy variable, I test it as a dependent variable and in a binary logistic regression.
This work contributes empirically to better understanding the gold OA
efficacy, which may be helpful in improving journals' rankings in the areas where
this is still a struggle. Significant results have been found for all variables, except
for the types of publishers, and for born or converted journals
La rappresentazione del valore nelle operazioni di Business Combination
Get PDFThe adoption of the IFRS 3 standard, and then of the IFSR 3R, has deeply affected the financial record and reporting of business combinations in common international practices, especially the Italian one. This study begins with the analysis of business combinations in compliance with the new IFRS 3R compared to those in accordance with what established by the Italian law and set in the Civil Code then developed by the OIC 4. It offers a detailed analysis of the evolution of the accounting practices of extraordinary operations, especially mergers.
We all know that when we compare the combination cost to the fair value of the acquired assets and liabilities, we usually obtain a difference, which can be positive if the combination cost is higher than the present value of the acquired assets and liabilities (in Italy it is commonly known as “combination deficit”), or negative, when the combination cost is lower than the present value of the acquired assets and liabilities (commonly known as “combination surplus”).
The aim of this study is to verify whether business combinations generate value or not and the ways of reporting and processing the possible surplus.
This study developed from another one made in 2009 by Hamberg, who analysed the business combinations listed in the Swedish Stock Market. He noticed that in the vast majority of the cases analysed, the surplus was completely ascribable to goodwill rather than to specific intangible assets. According to Hamberg, this could also be a consequence of opportunistic behaviors because while specific intangibile assets are subject to amortization, goodwill is subject to an impairment test. He thinks that goodwill impairments in compliance with IFRS are lower than the impairments of specific intangibile assets, with consequent higher returns in the years following the merger.
We have tried to carry out the same study on Italian companies, analysing all mergers between 2008 and 2012 regarding the businesses listed on the Italian Stock Market and therefore subject to IFRS standards. We made a first classification by distinguishing the business combinations that generated incomes from those which had a negative outcome that should be reported on the profit and loss account and therefore not relevant for this study. Then we focused only on those companies that generated goodwill, analysing the activity which reported the highest value. We found that the vast majority of the businesses allocated this value as goodwill rather than to other intangible assets.Therefore we confirmed the results obtained by Hamberg as for the Swedish companies. During the third stage we pointed out that goodwill did not experience any loss in value in the following years. This result could seem ambiguous as the reductions in value could have caused the immediate abatement of the returns. Hamberg considers this behaviour as a consequence of the increased stock market quotation experienced by the companies as he noted that businesses with a remarkable goodwill reported considerable increases in their returns
Anilate-based Functional Molecular Materials with Conducting and Magnetic Properties
Get PDFThis work reports on the design, synthesis and characterization of novel anilate-based
functional molecular materials showing magnetic and conducting properties.
The family of anilate ligands comprises several derivatives obtained by introducing various
substituents (H, F, Cl, Br, I, CN, Me, NO2, etc.) at the 3 and 6 positions of a common 2,5-dihyroxy-
1,4-benzoquinone framework. Their electronic/structural features, coordination modes and
ability to mediate magnetic exchange interactions between coordinated metal centers make
them suitable candidates for the preparation of the above-mentioned materials.
In Chapter 1, the syntheses of novel anilate-based ligands (anilate = An) having thiophene (Th),
3,4-ethylenedioxy-thiophene (EDOT), or Cl/CN as substituents are presented, along with their
crystal structures, the investigation of the emission (Cl/CN derivative) or charge-transfer (Th,
EDOT derivatives) properties and preliminary coordination chemistry studies.
Chapter 2 reports on a general synthetic strategy to achieve rationally designed tris-chelated
octahedral paramagnetic metal complexes, based on the combination of CrIII and FeIII as metal
ions with chloranilate, bromanilate, iodanilate, hydranilate and chlorcyananilate as ligands.
The crystal structure analyses, spectroscopical and electrochemical features, density functional
theory calculations, and the magnetic properties of these metal complexes of general formula
[A]3[MIII(X2An)3] (A = (n-Bu)4N+, (Ph)4P+; MIII = Cr, Fe; X = Cl, Br, I, H, Cl/CN) are described.
In Chapter 3 a novel class of molecule-based ferrimagnets formulated as [A][MnIIMIII(X2An)3] (A
= [H3O(phz)3]+, (n-Bu)4N+; MIII = Cr, Fe; X = Cl, Br, I, H), obtained according to the “complex-asligand”
approach by combining MnII metal ions with the [M(X2An)3]3- molecular building blocks
described in Chapter 2, is reported. The crystal structures and the magnetic properties for
these compounds are described, and the structure/properties correlation observed between
the ordering temperature values and the electron density on the ligand ring, associated with
the electron withdrawing properties of the X substituents, is particularly highlighted.
Chapter 4 reports on the structural diversity and the physical properties of three new
paramagnetic molecular conductors obtained combining the BEDT-TTF organic donor and the
[Fe(Cl2An)3]3- metal complex as conducting and magnetic building blocks, respectively. The
correlation between the crystal structure and conductivity behavior is reported.
Finally, in Chapter 5, the crystal structures and the physical properties of a complete series of
isostructural chiral molecular conductors obtained by combining the TM-BEDT-TTF organic
donor in its (S,S,S,S) and (R,R,R,R) enantiopure forms, or their racemic mixture (rac), with 2D
heterobimetallic anionic layers obtained in situ by association of tris(chloranilato)ferrate(III)
metal complexes and potassium cations are described.
As far as the framework of the thesis is concerned, this work is organized as follows. Part I
contains a general introduction on molecular materials, the state of the art and the aim of the
work. Part II contains the obtained results and their discussion divided in 5 Chapters whose
content has been summarized above. Part III contains the conclusions and the perspectives for
this work. Finally, Part IV contains 5 Appendixes where additional information (basic principles
of conductivity and magnetism, details on the electrocrystallization technique, etc.) are given
Textural features for fingerprint liveness detection
Get PDFThe main topic ofmy research during these three years concerned biometrics and in particular
the Fingerprint Liveness Detection (FLD), namely the recognition of fake fingerprints.
Fingerprints spoofing is a topical issue as evidenced by the release of the latest iPhone and
Samsung Galaxy models with an embedded fingerprint reader as an alternative to passwords.
Several videos posted on YouTube show how to violate these devices by using fake
fingerprints which demonstrated how the problemof vulnerability to spoofing constitutes a
threat to the existing fingerprint recognition systems.
Despite the fact that many algorithms have been proposed so far, none of them showed
the ability to clearly discriminate between real and fake fingertips. In my work, after a study
of the state-of-the-art I paid a special attention on the so called textural algorithms. I first
used the LBP (Local Binary Pattern) algorithm and then I worked on the introduction of the
LPQ (Local Phase Quantization) and the BSIF (Binarized Statistical Image Features) algorithms
in the FLD field.
In the last two years I worked especially on what we called the “user specific” problem.
In the extracted features we noticed the presence of characteristic related not only to the
liveness but also to the different users. We have been able to improve the obtained results
identifying and removing, at least partially, this user specific characteristic.
Since 2009 the Department of Electrical and Electronic Engineering of the University of
Cagliari and theDepartment of Electrical and Computer Engineering of the ClarksonUniversity
have organized the Fingerprint Liveness Detection Competition (LivDet). I have been
involved in the organization of both second and third editions of the Fingerprint Liveness
Detection Competition (LivDet 2011 and LivDet 2013) and I am currently involved in the acquisition
of live and fake fingerprint that will be inserted in three of the LivDet 2015 datasets
La divisione ereditaria
Get PDFStudying the division means trying to describe a complex phenomenon that accommodation dogmatic created many disagreements in doctrine and jurisprudence, and today, despite the debate on the subject has reached the landing at least reassuring, never fails to impress for a certain vitality.
The main purpose of this work is to analyze, with no claim to completeness, the division in modern key, both from a structural point of view that from a functional point of view.
Made a brief introduction on the history and evolution of legal profiles of the institute, it will switch you to the analysis of the essential elements that combine to describe the situation, to analyze its effects, and to place it, only if possible, within the categories of law developed by the doctrine and jurisprudence.
The second aspect of investigation, however, will focus on the study of the case divisional functionally analyzing in detail what are the various ways in which it is possible to proceed to division, and what are the critical issues relating to each divisional scheme, with particular attention to the division of the estate, which has always been, to its inherent complexity, the paradigm to refer to, and the ground of comparison of various theories proposed, in light of recent legislative changes, albeit marginal, report the current attention to a phenomenon instrumental in the distribution of wealth, perhaps too much overlooked
Causa e referenti obiettivi esterni
Get PDFOnce having defined the causa of an agreement (and, in general, of a juridical act, i.e. “negozio giuridico”) as its effective and objective purpose – the latter being the attitude of an act to realize a specific balance of interests (“causa concreta”) – the thesis is aimed at showing that the causa can be grounded (also) upon objective external referents, i.e. elements or circumstances which are able to constitute and influence the specific purpose of an act from an objective point of view, although they cannot per se be deduced from the subject matter (“oggetto”) and structure of the juridical act at hand. Such referents may consist in effects of different acts, or in facts and circumstances, including the context in which the act is concluded and will be performed.
Through an analysis of different juridical figures – with particular regard to links between agreements, atypical gratuitous acts and “pagamento traslativo”, guarantees and unilateral obligations to keep harmless, and acts of waiver – the attention is focused on the relevance of concurrence of interests (also based on external referents) in order to assess the real and effective causa, even in absence of any exchange of counterperformances (“sinallagma”) or of any purpose of liberality.
In light of the above, the thesis concludes dealing with some applicative consequences of the above-mentioned principles, with particular regard, on one side, to the assessment of validity and protectability of juridical acts and, on the other side, to the possibility to apply the remedies related to the termination of agreements when an external objective referent fails, even if the involved juridical act does not provide mutual counterperformances
I contratti di rete
Get PDFThe network contract, introduced into the Italian judicial system with the legislative decree February 10, 2009, n. 5 is a contract by which «more entrepreneurs pursue the aim of increasing, individually and collectively, their capacity for innovation and their competitiveness on the market and to this end they commit themselves, on the basis of a joint program of network, to collaborate in predetermined shapes and fields related to the exercise of their business, or to exchange information or services of an industrial, commercial, technical or technological nature or to exercise together one or more activities which belong to the scope of their business». It is a new legal judicial instrument designed by the legislature to renew the national economy and, in particular, the growth and the competitiveness of small and medium enterprises. The institute was founded as a response to the recent international crisis which has forced the companies to react and give a new impulse to the production system. To adapt themselves to this new requirement and operate in the national and international market, Italian companies have found in the contract a new form of aggregation through which they can achieve an entrepreneurial growth in terms of innovation and competitiveness, without having to resort to the establishment of a new legal entity. The first form of collaboration between companies was, in fact, that of the "industrial district" as socio-economic entity made up of a set of companies generally belonging to the same productive sector and located in determined and circumscribed area. Subsequently, the internationalization of companies and the globalization of markets has led to the failure of industrial districts and, at the same time, the emergence of business networks as a economic and legal phenomenon more complex. Business networks are characterized, in fact, by forms of association between two or more companies, independent from each other, which act in a coordinated way to make the small and medium enterprises more competitive in foreign markets. This form of aggregation, even promoted at European level with the "Small Business Act" of the European Commission, found a legal recognition in the new figure of the network contract, whose legal nature is still at the centre of a debate in doctrine