Il patriarcato di Aquileia: l'evoluzione dei poteri locali (1250 - 1420)

Il connotato signorile dell'aristocrazia friulana sembra generalmente risolversi nell'esercizio di alcune attribuzioni giurisdizionali esercitate su scala territoriale assai ridotta. In realtà il ruolo egemonico della nobiltà "castellana" poggiava in prevalenza sull'elemento patrimoniale, fonte, di per sé, di larghe ramificazioni di sapore clientelare presso la popolazione rurale. Non sempre, per altro, vi fu stretta convergenza territoriale fra diritti di giustizia e patrimonio fondiario; in molti casi quest'ultimo si configurava secondo zone di insistenza che esorbitavano decisamente dai luoghi di radicamento militare e "signorile" . Bertrando respinse l'idea di legittimare senz'altro un disegno distributivo delle influenze inteso nel senso della acquisizione definitiva. Né riteneva si dovesse trattare con la componente aristocratica senza l'intervento di un momento istituzionale in grado di limitarne l'autonomia e di controllarne i comportamenti. Sulla scia degli orientamenti che avevano guidato la politica torriana Bertrando continuò a considerare l'emergenza udinese e la tradizione di servizio dei Savorgnano come un nucleo di potere di straordinaria incidenza per coordinare in senso centralistico il disegno dei poteri locali. Nella ricerca di soluzioni orientate ad incrementare il peso del potere patriarchino nella società friulana, il patriarca privilegiava di norma il momento alto e risolutivo della risorsa politico-militare piuttosto che la progressiva costruzione di una rete di aderenze larga e capillare, ma variamente frammista al sistema delle influenze aristocratiche. Per l'impostazione di fondo, l'intervento bertrandiano doveva scontare, d'altra parte, tutti i rischi connessi ad una destabilizzazione radicale delle gerarchie di potere - tanto fra i nobiles quanto fra le comunitates - e l'eventualità di una frattura "critica" con lo schieramento avverso

Ultrafast photodoping and effective Fermi-Dirac distribution of the Dirac particles in Bi2Se3

We exploit time- and angle- resolved photoemission spectroscopy to determine the evolution of the out-of-equilibrium electronic structure of the topological insulator Bi2Se. The response of the Fermi-Dirac distribution to ultrashort IR laser pulses has been studied by modelling the dynamics of the hot electrons after optical excitation. We disentangle a large increase of the effective temperature T* from a shift of the chemical potential mu*, which is consequence of the ultrafast photodoping of the conduction band. The relaxation dynamics of T* and mu* are k-independent and these two quantities uniquely define the evolution of the excited charge population. We observe that the energy dependence of the non-equilibrium charge population is solely determined by the analytical form of the effective Fermi-Dirac distribution.Comment: 5 Pages, 3 Figure

Mycochemical study of polysaccharides from the edible mushroom Cortinarius caperatus (Gypsy mushroom)

Among basidiomycete molecules, cell wall polysaccharides have been recognized as a major class of bioactive constituents. [1] They are safe molecules and they have a wide spectrum of biological activities, such as immunostimulatory and antioxidant, therefore they possess a prominent role in health benefits coming from mushroom consumption. These properties make mushroom polysaccharides potential candidates for nutraceutical applications and bioactive ingredients production. [2] Fractionation of the hot aqueous extract of Cortinarius caperatus led to isolation of two fractions characterized by spectroscopic analyses (1H-NMR, 13C-NMR, DEPT, 1H-1H COSY, DQCOSY, TOCSY, HSQC, HMBC and HMQC), mass spectrometry (EI-MS, ESI-MS), infrared spectroscopy (FT-IR), chemical reactions of hydrolysis and derivatization followed by GC and HPLC analyses. [3] This mycochemical study revealed a water-soluble fraction characterized as a \u3b2-(1\uf0e06)-D-glucan, whose presence inside C. caperatus has never, to the best of our knowledge, been reported before. Moreover, a water insoluble fraction purified has been characterized as a branched \uf061, (1\u21926) glucan which structure is assumed to be: [\u21926)-\u3b2-D-Glcp(1\u21926)]4-\u3b1-D-Glcp(1\u21924)-\u3b2-D-Glcp(1\u2192 6 \u2191 1 \u3b1-D-Glcp The antioxidant activity of the soluble polysaccharide fraction has been evaluated as radical-scavenging activity with the DPPH test, the \u3b2-(1\uf0e06)-D-glucan showed significative antioxidant activity

A New Bi-Functional Derivative of Polyethylene Glycol as Molecular Carrier for Eugenol and Ibuprofen

Eugenol (EU) and ibuprofene (IBU) were covalently bound to a bi-functionalized PEG, used as molecular carrier of drugs and the release kinetics of the two bioactive molecules was studied in vitro in buffer solution at pH 7.4, in simulated gastric fluid and in mouse plasma. The hydrolysis studies showed a specific cleavage dependent on the pH of the medium and by the presence of proteolytic enzymes in mouse plasma. Studies in vitro on the release of the parent drug from this double prodrug in various media, indicate that the adduct may be sufficiently stable to pass intact the gastrointestinal tract and release into the circulation EU and IBU. Many advantages may be achieved by the synthesis of the prodrug EU-PEG-IBU related to synergistic analgesic and anti-inflammatory effects, to the reduction of the adverse reactions and the improvement of the chemical-physical properties of the parent drugs

Ultrafast Optical Control of the Electronic Properties of ZrTe5ZrTe_5

We report on the temperature dependence of the $ZrTe_5$ electronic properties, studied at equilibrium and out of equilibrium, by means of time and angle resolved photoelectron spectroscopy. Our results unveil the dependence of the electronic band structure across the Fermi energy on the sample temperature. This finding is regarded as the dominant mechanism responsible for the anomalous resistivity observed at T* $\sim$ 160 K along with the change of the charge carrier character from holelike to electronlike. Having addressed these long-lasting questions, we prove the possibility to control, at the ultrashort time scale, both the binding energy and the quasiparticle lifetime of the valence band. These experimental evidences pave the way for optically controlling the thermoelectric and magnetoelectric transport properties of $ZrTe_5$

New Triterpenes from the Fungus Gloeophyllum odoratum

Two new triterpene acids (1, 2), together with a complex mixture of lecithins (3), were isolated from the fungus Gloeophyllum odoratum. Their structures were elucidated on the basis of extensive spectroscopic analyses. The extract of Gloeophyllum odoratum considerably inhibited thrombin (72% at a concentration of 120 g/mL); the less polar fraction of the methanolic extract from the mushroom exhibited interesting activity (47% at a concentration of 120 g/mL) against thrombin. Compounds 1 and 2 were responsible for this activity

Evolution of the quasiparticle spectral function in cuprates

We analyzed photoemssion data for several doping levels of the Bi_2Sr_2CaCu_2O_{8+x} compounds, ranging from overdoped to underdoped. We show that the high frequency part of the spectra near (0,\pi) can be described by Fermi liquid theory in the overdoped regime, but exhibits a non-Fermi liquid behavior in the underdoped regime. We further demonstrate that this novel behavior fits reasonably well to a 1/\sqrt{\omega} behavior suggested for systems with strong spin fluctuations.Comment: 5 pages, 2 figures (EPS), RevTeX, submitted to Phys Rev B R

New electronic orderings observed in cobaltates under the influence of misfit periodicities

We study with ARPES the electronic structure of CoO2 slabs, stacked with rock-salt (RS) layers exhibiting a different (misfit) periodicity. Fermi Surfaces (FS) in phases with different doping and/or periodicities reveal the influence of the RS potential on the electronic structure. We show that these RS potentials are well ordered, even in incommensurate phases, where STM images reveal broad stripes with width as large as 80\AA. The anomalous evolution of the FS area at low dopings is consistent with the localization of a fraction of the electrons. We propose that this is a new form of electronic ordering, induced by the potential of the stacked layers (RS or Na in NaxCoO2) when the FS becomes smaller than the Brillouin Zone of the stacked structure