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By Monte Carlo simulations we investigate the spectrum of voltage fluctuations of Si layers of variable thickness W in the range 2 ÷ 100 nm and variable length L in the range 10÷1000 nm embedded in an external dielectric medium. Calculations are performed at T = 300 K for di!erent doping levels and in the presence of an external bias of increasing strength. For W ! 100 nm and carrier densities of 5 " 10 17 and 5 " 10 18 cm ! 3 the peaks agree with the value of the three dimensional (3D) plasma frequency. For W # 10 nm the results exhibit a plasma frequency that depends on L, thus implying that the oscillation mode is dispersive. The corresponding frequency covers a wide range of values 0.2 ÷ 10 THz and is in agreement with the values predicted by existing analytical models. At su"ciently high bias the 2D plasma peak is washed out and we observe the onset of a peak in the subTHz region which, by analogy with the results obtained in n-InGaAs layers, is associated with transit time instabilities induced by current saturation conditions.

By means of Monte Carlo simulations coupled with a two-dimensional Poisson solver, we evaluate directly the possibility to use high mobility materials in ultra fast devices exploiting ballistic transport. To this purpose, we have calculated specific physical quantities such as the transit time, the transit velocity, the free flight time and the mean free path as functions of applied voltage in InAs channels with different lengths, from 2000 nm down to 50 nm. In this way the transition from diffusive to ballistic transport is carefully described. We remark a high value of the mean transit velocity with a maximum of 14×105 m/s for a 50 nm-long channel and a transit time shorter than 0.1 ps, corresponding to a cutoff frequency in the terahertz domain. The percentage of ballistic electrons and the number of scatterings as functions of distance are also reported, showing the strong influence of quasi-ballistic transport in the shorter channels.

We present a hydrodynamic model to simulate the excitation by optical beating of plasma waves in nanometric field effect transistors. The biasing conditions are whatever possible from Ohmic to saturation conditions. The model provides a direct calculation of the time-dependent voltage response of the transistors, which can be separated into an average and a harmonic component. These quantities are interpreted by generalizing the concepts of plasma transit time and wave increment to the case of nonuniform channels. The possibilities to tune and to optimize the plasma resonance at room temperature by varying the drain voltage are demonstrated.

The possibility of cultivating in vitro human kerathinocytes has opened new prospectives in the surgical treatment of major burns and, generally, in patients with extensive skin loss (degloving, etc.). Epidermidal sheets, obtained in vitro, have been used initially, successfully, as autografts. Later, their peculiar immunological characteristic (absence of Langerhans cells expressing class II MHC antigens and inability of evocating omograft rejection) has allowed it's use as allograft without the need of resorting to treatment with immunosuppressive drugs. Medico-legal problems raised by the use of human epidermys cultivated as allograft are described hereafter.

Using a self-consistent Monte Carlo simulator we investigate the spectrum of voltage fluctuations of an n-type InGaAs two-terminal layer of variable thickness W in the range 1-100 nm and variable length L in the range 0.01-10 µm embedded in an external dielectric medium. Calculations are performed at T = 300 K for different dopings and in the presence of an external bias of increasing strength. When the bias is well below the threshold for the Gunn effect the spectrum peaks at the plasma oscillations of the electron gas. For W≥100 nm and carrier concentrations of 10(17)-10(18) cm(-3) the peaks are in good agreement with the standard three-dimensional (3D) expression of the plasma frequency. For W≤10 nm the results exhibit a plasma frequency that depends on the length of the layer, thus implying that the oscillation mode is dispersive. The corresponding frequency covers a wide range of values 0.1-10 THz and is in agreement with the two-dimensional (2D) expression of the plasma frequency obtained for a collisionless regime within the in-plane approximation for the electric field. A region of cross-over between the 2D and 3D behaviours of the plasma frequency is shown for W10 nm. When the bias is above the threshold for the Gunn effect, we observe the washing out of the plasma peak and the onset of a frequency peak associated with the transit time of the Gunn domain located in the sub-terahertz frequency region.

The Mn(II)-lecithin system was investigated by means of paramagnetic relaxation studies. Unsonicated and sonicated aqueous dispersions were considered at various temperatures andpH values. Information was derived from both the frequency dependence of the ESR line shape and the paramagnetic contributions to the water proton relaxation rates. A dynamic equilibrium was suggested, by taking into account the role of the through-water cation binding in the metal-lipid interaction.

SummaryMeasurements of blood juvenile hormone (JH), protein, and vitellogenin contents were carried out on adult queen honeybees during their first summer and winter and second summer, and with workers 12 and 25 days old. The JH titre was slightly higher in laying queens than in non-laying queens, but no higher than in workers.The titres of protein and vitellogenin were higher in queens than in workers, but no differences were obvious between laying queens and non-laying queens. No correlations were found between the titres of JH, protein and vitellogenin in queens. In both queens and workers the JH titre was positively correlated with age.

Forty-five samples of honey produced in Emilia-Romagna between June and September 1974 have been subjected to gaschromatography to check for the presence of residues of chlororganic and phosphorganic phytodrugs. Residues of chlororganic phytodrugs in appreciable amounts have been found to be present in 11 samples only, more precisely lindane has been reported in 6 samples, aldrin in 4 samples, DDT in 4 samples, DDD and dieldrin respectively in one sample only. The higher concentration for DDT has been 0,04 ppm. No residues of phosphorganic phytodrugs have been found to be present in any of the samples examined. As the presence of residue has been observed only in a small number of samples and low concentration have been found, we belive that the problem of honey pollution by phytodrug residues is a minor one, even when related to the situation of foods in general.

Among the many cases of teeth subjected to trauma, this one, that it has been observed, was fit for an attempt of replant for the good possibilities of success; it has been considered the age, very young, of the patient, the good health and principally her good orodental situation. Two radiografies made after short time have revealed the formation of osseus trabeculae, irrefutable sign of taking root.

This work is based on the observation of 15 patients with an age from 20 to 55 years, with different chronic odontitis, that have been treated with placenta extract close to the typical therapy. The results, already reached after two months, have been satisfactory, whether for the inflammation or for the distrophic forms, for the good balance of applications, topical and intramuscular.

Any multispin system can be reasonably approximated by a sum of pairwise spin-spin interactions. As a consequence spin-lattice relaxation of any spin i coupled to a group of spins j can be approximated by summing the relaxation effects of all the spin pairs, yielding (1): $$d /dt = -{R_i}\left( { -{I_{0i}}} \right) - \sum\limits_{i \ne j} {{\sigma _{ij}}} \left( { - {I_{0j}}} \right)$$ (1) where $${R_i} = \sum\limits_{i \ne j} {{\rho _{ij}} + {\rho _i} * }$$ (2) Ioi is the equilibrium value of which represents the expectation value of the nuclear spin operator and it is proportional to the total integrated intensity of the NMR signal. σij is the cross relaxation term which is usually contributed by dipole-dipole interactions only. ϱij is the dipole-dipole direct relaxation term, while ϱi* accounts for direct relaxation of spin i due to mechanisms other than the dipole-dipole.

The research is intended to get knowledge of some enzymatic activity of Actinomyces Israeli bacteria isolated from the mouth of several subjects and it shows how such bacterium can give rise to erosive phenomena of the enamel of the teeth and also to infections of the periodontal through a process causing the formation of a cloudy halo in the cultures.

Nel 1732 Alfonso Maria de Liguori fondava la Congregazione del SS. Redentore con l’intento di portare aiuto, con i suoi missionari, nelle periferie dimenticate, maggiormente bisognose di un conforto spirituale. Nel 1749 Benedetto XIV approvava la regola. Le riflessioni che seguono ripercorrono i primi anni di vita della Congregazione fra speranze, successi, fallimenti, facendo ricorso al carteggio del de Liguori ed ai suoi principali interlocutori quali Benedetto XIV, Carlo di Borbone, monsignor Tommaso Falcoia, suor Celeste Crostarosa

In Italy the transition from a war economy to a peacetime economy began before the end of the first world war. To the parties involved – the state, the industrialists and the workers – it was clear that the war had created a dramatic rupture in the organisation of production. The post-war period ushered in a phase of great turmoil, especially in trade union relations between industrialists and workers. The issues at the centre of the discord were the supply of raw materials, unemployment, the cost of living, and higher wages. As the hostility grew, the industrialists, who in the meantime had re-established their association (Confindustria) in order to defend their interests more effectively, decided to finance the National Fascist Party (PNF). This support, with the rise to power of Benito Mussolini, enabled order to be established in the factories by means of coercion and punishment of worker demands. Italy’s process of industrial reconversion therefore went no further than the industrialists’ recourse to a “strong state”, a prospect that was far from isolated in Europe.

Young massive stars are usually found embedded in dense and massive molecular clumps and are known for being highly obscured and distant. During their formation process, deuteration is regarded as a potentially good indicator of the formation stage. Therefore, proper observations of such deuterated molecules are crucial, but still, hard to perform. In this work, we test the observability of the transition o-H$_2$D$^+(1_{10}$-$1_{11})$, using a synthetic source, to understand how the physical characteristics are reflected in observations through interferometers and single-dish telescopes. In order to perform such tests, we post-processed a magneto-hydrodynamic simulation of a collapsing magnetized core using the radiative transfer code POLARIS. Using the resulting intensity distributions as input, we performed single-dish (APEX) and interferometric (ALMA) synthetic observations at different evolutionary times, always mimicking realistic configurations. Finally, column densities were derived to compare our simulations with real observations previously performed. Our derivations for o-H$_2$D$^+$ are in agreement with values reported in the literature, in the range of 10$^{\!10-11}$cm$^{\!-2}$ and 10$^{\!12-13}$cm$^{\!-2}$ for single-dish and interferometric measurements, respectively., Comment: 3 pages, 3 figures, To appear in the proceedings of the Second Binational Meeting AAA-SOCHIAS 2018

Completely overturning this traditional portrait, the authors suggest that during the early modern period Spain, Portugal, Italy, and Latin America indeed took a different path when compared to other European and American countries. However, this divergence was not caused (and therefore cannot be explained) by underdevelopment. Paradoxically, what was common to all former Spanish territories was not “failure” but instead “success.” Local peripheral groups became integrated into (and benefited from) colonial structures, forming larger commercial circuits, purchasing offices and ecclesiastical benefits created or sold by the Monarchy, and participating in wider markets of public debt. Also all these areas shared a relative resilience to the economic downturn, which characterized other Mediterranean countries during the same period. Rather than decaying, Spanish controlled territories blossomed or, so was at least, the situation in the seventeenth century.

Il volume analizza il ruolo dei Carafa di Maddaloni nell’ambito della stratificata feudalità europea tra età medievale e moderna, già oggetto di studio dell’erudito tedesco Alfred Von Reumont, conosciuto per una celebre biografia di Lorenzo il Magnifico. il volume consegue risultati inediti sulla base dello spoglio puntuale del fondo documentario della famiglia riordinato da Benedetto Croce e Giuseppe Ceci e del fondo documentario “Relevi”, entrambi conservati preso l’Archivio di Stato di Napoli. L’accurato e complesso studio del materiale documentario permette di illuminare in modo circostanziato i fondamentali passaggi che assicurarono per diversi secoli l’acquisizione di una consistente rendita feudale in diverse province del regno e un ruolo di privilegio e di preminente autorità della famiglia nella capitale e nell’intero Mezzogiorno continentale. La ricerca contenuta nel volume restituisce l’immagine di un potere feudale - e quello rappresentato dai Carafa di Maddaloni è senz’altro da ritenere tra i più preminenti - per nulla statico e chiuso in se stesso, ma anzi esplicitamente intento ad allineare le proprie strategie non soltanto nei confronti della dinastia regnante. ma anche rispetto agli esponenti dei ceti sociali ed economici più ragguardevoli del regno at traverso un continuo sforzo di costruzione e inquadramento del casato all’interno di una ramificata rete di rapporti. Ne emerge un affresco originale, che arricchisce la letteratura sulle forme dell’egemonia delle famiglie nobiliari nelle società di Antico Regime. Gli importanti risultati conseguiti dalla ricerca hanno avuto ampio riconoscimento nel corso di convegni sulla storia della feudalità in Italia e in Europa. Il libro è alla sua seconda edizione ed è prevista nei prossimi mesi la pubblicazione in lingua spagnola.

Departamento de Alimentos e Nutricao Experimental, Faculdade de Ciencias Farmaceuticas da Universidade de Sao Paulo (USP), Sao Paulo, Brazil. Received 26 June 2008, accepted subject to revision 18 August 2008, accepted for publication November 2008. *Corresponding author: Email: annagloria.sabatini@entecra.it

Nell’ambito del progetto KASA (Koine Archeologica - Sapiente Antichità), progetto finanziato dall’Interreg Italia-Malta, promulgato dalla Regione Sicilia, con fondi della Comunità Europea, la Missione Archeologica Italiana diretta dal Prof. Pietro Militello dell’Università di Catania ha affrontato uno studio sugli antichi ambienti sotterranei sui quali insiste il Museo Wignacourt a Rabat (Malta). I risultati sono presentati in questo volume che si articola in quattro sezioni. La prima, curata da G. Azzopardi, curatore del Museo, consiste in una raccolta di notizie storiche utili alla ricostruzione della frequentazione umana degli ingrottamenti dal XVI secolo circa fino alla Seconda Guerra Mondiale, allorquando vennero realizzati ampi rifugi sotterranei antiaerei. La seconda sezione, curata da F. Sabatini, contiene la presentazione dei maggiori complessi ipogeici (1-6), preceduta da note di carattere generale su aspetti geologici e seguita da considerazioni sulle tecniche dell’“architettura per via di levare” delle catacombe maltesi. La terza parte presenta i complessi ipogeici 7-15, a cura di V. Rizzone, e 16, a cura di F. Tomasello e della sua équipe. Lo studio di questi estesi cimiteri sotterranei offre la possibilità di svolgere una serie di considerazioni generali (sezione quarta) sulla nascita e lo sviluppo degli ipogei funerari di Rabat, sulle tecniche di rilevamento e sulla loro valorizzazione.