170,916 research outputs found
PATRIARCA C. Commento all'art. 127 bis TUF. In: AA. VV.. (a cura di): Pietro Abbadessa, Giuseppe B. Portale, Vincenzo Cariello e Umberto Tombari, Le fonti del diritto italiano. Codice delle società per azioni, MILANO:GIUFFE'
No full textIl contributo analizza la disciplina della legittimazione all'impugnazione delle delibere assembleari nel sistema della c.d. record date introdotto per le società quotate dal d.lgs., 28/201
Nomina degli amministratori di società di capitali, regime dell’ineleggibilità e profili formali
No full textThe essay analyzes the space of new rules relating the disqualification of directors of companies according Italian Companies Law and the new formal duties of directors concerning their appointmentIl contributo analizza la portata delle nuove norme in tema di ineleggibilità degli amministratori delle società di capitali e sui nuovi obblighi formali
Structural transitions of cytochrome c: implication for apoptotis and peroxidase actvity
No full textThe discovery of new functions of cytochrome c was a good example to study the evolutionary processes and it is a stunning example of the collapse of an old dogma:”one gene, one protein, one function”. Cytochrome c is a small heme protein, a soluble protein and an essential component of the mitochondrial respiratory chain because of its capability to transfer electrons between the III and IV complexes. Beyond the role as electron carrier in the respiratory chain, cytochrome c is involved in the triggering of apoptosis “programmed cell death”. Cytochrome c, released from the inner mitochondrial membrane in response to specific signals, binds to Apaf-1, nucleotides (dATP or ATP) and procaspase 9 to form the apoptosome in the cytosol. All these important biological activities are realized in its native structure. Studies from several laboratories document that the unfolding of cytochrome c reveals a new function as a peroxidase. With this in mind, the aim of the present thesis was to define the role of the binding ATPcytochrome c and to demonstrate the importance of the ATP as an allosteric effector, in regulating structural transitions among different conformations and different oxidation states of cytochrome c, endowed or not with apoptotic activity. The present study suggests a physiological role for ATP binding to cytochrome c at low millimolar concentrations in the cytosol, beyond the regulatory role previously reported in the oxidative phosphorylation in mitochondria. For the experiments, it has been used the horse heart cytochrome c, a single polypeptide chain organized in five smallhelices and three omega loops. The prosthetic group is linked to the polypeptide chain by means of two tioether bonds formed by cysteins in position 14 and 17. The heme-iron is also axially coordinated with the two residues His18 and Met80. In the present work, the structural and functional properties of single mutants K88E, E62N, R91N and double mutant K88E/E62N have been compared, because in previous studies the binding site of ATP had been identified by docking simulations. By performing NMR measurement it has been demonstrated that ATP interacts with a site (S1) formed by K88, R91 and E62. Glu62 and Lys88 are replaced by Asn and Glu, present in the iso-1 cytochrome c sequence that is not able to interact with ATP. R91N has been analyzed because it‟s conserved in all species of cytochrome c and it is implicated in the binding of ATP to cytochrome c. The apoptotic activity of cytochrome c variants has been studied by using a “cell-free” activation assay. In the second part of this thesis it has been studied the peroxidase activity of non-native variants of cytochrome c. Native cytochrome c is characterized by a compact tertiary structure and is thus unavailable for binding of any other compound. The bond between the methionine residue and the heme iron, however, is rather weak so that it‟s easily broken and facilitates the access of small molecules, such as H2O2, in the heme pocket. In particular, the access of H2O2 determines the change of cytochrome c into Compound I-type peroxidase. At the aim of investigating the peroxidase activity of non-native cytochrome c, different forms of the protein have been analyzed in order to correlate their structural features with the acquired enzymatic activity. We studied the structural features of cytochrome c bound to cardiolipin (CL)-containing liposomes and Y67H and H26Y cytochrome c mutants. Histidine in position 26 was changed with a tyrosine (H26Y) because it was highlighted the contribution of the hydrogen bond linking the histidine in position 26 (Ωloop 20s) to the carbonyl group of the residue 44 (Ω-loop 40s), to the stability, folding, and functional properties of cytochrome c. The other mutation was concerning with Tyr67, which was replaced by a histidine (Y67H), with the aim of introducing a general acid–base catalyst, a fundamental element of the peroxidase mechanism, in the heme cavity. The spectroscopic features of cytochrome c/CL complex, H26Y and Y67H mutants were analyzed and the biological significance of the observed conformational changes was inferred by the relationship with their peroxidase activities and apoptogenic properties. To gain further insights on the capability of ATP to function as allosteric regulator of cytochrome c conformational transitions, its effect on refolding and its modulation of the peroxidase activity of cytochrome c variants were also investigated. Moreover, the peroxidase kinetic parameters of the non native conformers here investigated were measured also in the presence of minocycline, an antibiotic endowed with antioxidant properties reported to act as peroxidase inhibitor and neuroprotective agent that delays progression of neuron degeneration
PATRIARCA C Commento all'art. 2379. In: AA. VV.. (a cura di): Pietro Abbadessa, Giuseppe B. Portale, Vincenzo Cariello e Umberto Tombari, Le fonti del diritto italiano. Codice delle società per azioni, MILANO:GIUFFE' (paragrafi §§ 1, 3, 8 e 9)
No full textIl commento affronta i moteplici problemi sollevati dalla nuova disciplina della nullità delle delibere assemblear
Acute myeloid leukemia following chronic low-dose cyclophosphamide in metastatic breast cancer
No full textTraumatic shock and electroshock: the difficult relationship between anatomic pathology and psychiatry in the early 20th century
No full textIn the conviction that a look at the past can contribute to a better understanding of the present in the field of science too, we discuss here two aspects of the relationship between early 20th century anatomic pathology and psychiatry that have received very little attention, in Italy at least. There was much debate between these two disciplines throughout the 19th century, which began to lose momentum in the early years of the 20th, with the arrival on the scene of schizophrenia (a disease histologically sine materia) in all its epidemiological relevance. The First World War also contributed to the separation between psychiatry and pathology, which unfolded in the fruitless attempts to identify a histopathological justification for the psychological trauma known as shell shock. This condition was defined at the time as a "strange disorder" with very spectacular symptoms (memory loss, trembling, hallucinations, blindness with no apparent organic cause, dysesthesias, myoclonus, bizarre postures, hemiplegia, and more), that may have found neuropathological grounds only some hundred years later. Among the doctors with a passed involvement in the conflict, Ugo Cerletti, the inventor of electroshock treatment, focused on the problem of schizophrenia without abandoning his efforts to identify its organic factors: if inducing a controlled electric shock, just like an experimentally-induced epileptic seizure, seems to allay the psychotic symptoms and heal the patient, then what happens inside the brain? In seeking histological proof of the clinical effects of electroconvulsive therapy ("the destruction of the pathological synapses"), and attempting to isolate molecules (that he called acroagonins) he believed to be synthesized by neurons exposed to strong electric stimulation, Cerletti extended a hand towards anatomic pathology, and took the first steps towards a neurochemical perspective. However his dedication to finding a microscopic explanation for schizophrenia - in the name of a "somatist" approach that, some years earlier, the psychiatrist Enrico Morselli had labelled "histomania" - was unable to prevent psychiatry from moving further and further away from anatomic pathology
An Explicit Threshold for the Appearance of Lift on the Deck of a Bridge
No full textWe set up the analytical framework for studying the threshold for the appearance of a lift force exerted by a viscous steady fluid (the wind) on the deck of a bridge. We model this interaction as in a wind tunnel experiment, where at the inlet and outlet sections the velocity field of the fluid has a Poiseuille flow profile. Since in a symmetric configuration the appearance of lift forces is a consequence of non-uniqueness of solutions, we compute an explicit threshold on the incoming flow ensuring uniqueness. This requires building an explicit solenoidal extension of the prescribed Poiseuille flow and bounding some embedding and cutoff constants
Agostino Gemelli and the scientific study of courage in the First World War
No full textAgostino Gemelli (1878-1959) is known as the founder of the Catholic University in Italy. Franciscan monk and doctor he had a central role in promoting studies on human behavior, thanks to his solid scientific training as a student of Camillo Golgi at the University of Pavia. His research activities during the years of the First World War involved studying the motivation, courage and psychological adaptation of the soldiers, engaged in trench warfare, laying the foundations of modern studies of behavior and trauma
Time and frequency GPR waveforms analysis for clay content evaluation in soils
No full textThe mechanical behaviour of soils is partly affected by their clay content, which exerts some considerable effects in many applications in the fields of civil engineering, geology and environmental engineering. This study focuses on pavement engineering, but the approach can be extended to other purposes.
The presence of clay in the bearing structural layers of pavements frequently causes damages and defects, such as transversal and longitudinal cracks, deformations and rutting. Consequently, the road safety and operability decrease, while the expected number of accidents increases.
In this work Ground Penetrating Radar (GPR) laboratory inspections are carried out in order to predict the presence of clay in pavement structural layers. Data are post-processed in the frequency domain, according to the Rayleigh scattering method based on the Fresnel theory. This new technique can be supported by other survey methods, improving the quality of the results.
Analysis are carried out using two different GPR systems.
A Radar is used with ground-coupled antennae in a bistatic configuration and common offset; the transmitter and receiver are linked by optic fiber electronic modules and operate at 500 MHz central frequency. The received signal is sampled in the time domain at time steps of 7.8125 x 10-2 ns.
A Vector Network Analyzer (VNA) acquires ultra-wide band data in a bandwidth from 500 MHz to 3000 MHz. The signal is sampled in the frequency domain with approximately 1.56 MHz frequency steps. A double-ridged broadband horn antenna is connected via a high-quality coaxial cable to the VNA pulse generator and illuminates the analyzed target in a monostatic off-ground configuration.
The experimental setting required the use of road material, typically employed for sub-grade and sub-base layers. Three kind of soils, classified as A1, A2, A3 by AASHTO are used and adequately compacted in electrically and hydraulically isolated boxes. Bentonite clay is gradually added from 2% to 25% in weight, according to mixing and compaction laboratory procedures. A metal plate supports the experimental boxes, so that the GPR signal is totally reflected.
GPR surveys are carried out for each clay content. The signals are analyzed in both time and frequency domains.
In the time domain the reliability of results is validated by the electromagnetic theory, in terms of signal amplitude, electric permittivity and time delay . In the frequency domain the results are highly consistent for all the investigated soils . Assuming a residual water content of the dry clay that is due to its hygroscopic capability, frequency spectra shift not linearly, as expected from the scattering theory. The modulation depends on the water content and, indirectly, on the clay content. The correlation between the central frequency values of the spectra and the clay content is negative: decreasing values of the central frequency correspond to increasing values in the clay content, from 0% up to 25%. A comparative analysis of the three soil spectra for different clay contents has shown a different behaviour of the clay, both for the ground-coupled radar and the broadband analyzer. In general, in fine grain size soils lower central frequency value intensities are registered
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