0000000000514670

AUTHOR

G. Ferrante

Unusual optical properties in ultra short laser pulse interaction with dense nonequilibrium plasma

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NON SOLO PORPORA… SUCCESSO DELLA STRATEGIA TERAPEUTICA E NUTRIZIONALE

La porpora di Schoenlein-Henoch (HSP) è la vasculite più comune in età pediatrica caratterizzata da depositi di immunocomplessi di IgA nei piccoli vasi. L’eziologia non è nota, ma è possibile una correlazione con infezioni batteriche, virus, alimentazione, punture di insetti e agenti fisici. La diagnosi è principalmente clinica. Le principali manifestazioni sono porpora cutanea, artrite, manifestazioni gastrointestinali e nefrite. Manifestazioni neurologiche e cardiache sono rare, come le localizzazioni polmonari e testicolari. Sporadicamente è descritto un coinvolgimento pancreatico. Riportiamo il caso di un bambino di 5 anni con HSP ad interessamento pluridistrettuale. B.G. giunge alla no…

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Parametric Excitation of Density Waves in Drifting Electron-Hole Plasmas

The effect of the electronic drift velocity on the conditions for parametric excitation in electron-hole plasmas is investigated in the two-mode approximation using a Vlasov-equations approach. The results show that when the electronic drift velocity approaches the phase velocity of the lower frequency mode of the plasma, a considerable lowering of the threshold for the onset of parametric excitation occurs, thus resulting in more favorable conditions for experimental observation of the process. The dependence of the threshold on other relevant physical parameters involved, such as the electron-to-hole mass and temperature ratios, is also investigated.

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New Results on Multiphoton Free-Free Transitions

Recently some of the present authors have reported on calculations concerning free-free transitions in the presence of very strong laser fields,1 in which a number of peculiar features were clearly displayed (among others, well pronounced maxima in the total cross sections and an oscillatory structure). In particular, those calculations concerned total cross sections of direct and inverse multiphoton bremsstrahlung, for several numbers of exchanged photons as functions of the field intensity. Figs. 1 and 2 show a sample of the typical results reported in Ref. 1.

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Modifications of high harmonic spectra by ion resonant transitions

High-order harmonic generation is considered in a system consisting of an ion with an internal degree of freedom plus an outer electron. The theoretical treatment is both quantum-mechanical and classical. The emphasis is on the core resonance effects, which can significantly modify the harmonic spectra, with appearance of anomalous peaks. Under some assumptions, the spectral amplitude of the resonant harmonic of the system dipole moment can be obtained by evaluation of such amplitude within a single-electron approximation and multiplication of the result by a correcting factor. The latter depends on the polarizability of the ion and of a free electron at the harmonic frequency. Copyright © …

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Effect of the non-gaussianity on the measurement error for the filtered 1/f noise intensity

To study the nature of the 1/f noise phenomenon in conductors, we seek a tool for testing different hypotheses of 1/f noise origin. The method analyzing the noise intensity at the output of a bandpass filter is discussed for the case of non-Gaussian processes. Data on measurement error are presented for the 1/f noise intensity in GaAs films and the Gaussian white noise emulated by a computer. A numerical model of 1/f noise as the superposition of telegraph random processes has been created. This method requires further improvement to check the noise for stationarity. Some ideas of how to do that are proposed.

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Unusual optical properties of the dense nonequilibrium plasmas

A concise overview of new optical properties of dense nonequilibrium plasma formed on the solid state target boundary is given. In this chapter, we describe phenomena such as the third harmonic generation in the skin layer, collisionless electron heating in the high frequency skin-effect regime, absorption, and reflection and transmission of radiation by a plasma with anisotropic electron distribution.

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Valutazione dell’accessibilità con software open source

L'accessibilità ha da sempre ricoperto un ruolo fondamentale per lo sviluppo delle società e per rendere sempre più agevoli gli spostamenti, a prescindere dalle cause che li originano. In questo articolo si vuole focalizzare l’attenzione sull’accessibilità ai terminal aeroportuali, in quanto la velocità e la facilità di accesso sono aspetti strategici per il trasporto aereo. Se il tempo di accesso ai terminal non fosse sufficientemente rapido, negli spostamenti a breve distanza, l’aereo perderebbe il vantaggio che ha sulle altre scelte modali. Lo scopo che ci si è posti nella ricerca è di valutare l’accessibilità territoriale attraverso l’uso di software GIS (Geographic Information System) …

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COMMENT ON THE SPACE TRANSLATION METHOD AS USED IN LASER-ASSISTED COLLISION PROBLEMS

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Relationship between quality of life and behavioural disorders in children with persistent asthma: a Multiple Indicators Multiple Causes (MIMIC) model

AbstractKnowledge on multiple interdependences between quality of life (QoL) and behavioural problems in relation to asthma severity and control is undetermined. The aims of the study were: (i) to assess the relationship of QoL and behavioural problems with asthma severity and control (ii) to predict children’s “abnormal/borderline” status with variation in QoL. For these purposes a multicenter case-control study on 47 Severe Asthma (SA) and 94 Moderate Asthma (MA) children was performed. The MIMIC approach was applied to investigate the effect of SA and non-controlled asthma (NC) on QoL and behavioural disorders. Logistic regression was used to estimate probabilities of having an “abnormal…

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Even and Odd Harmonic Generation in low-doped semiconductors

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Phase II study of mitomycin C, etoposide and vindesine in metastatic stage IV non-small-cell lung cancer.

A total of 72 patients with metastatic stage IV non-small-cell lung cancer (NSCLC) were treated with combination chemotherapy comprising the MEV regimen (mitomycin C, 8 mg/m2 given i. v. on day 1; etoposide, 100 mg/m2 given i.v. on days 1–3; and vindesine, 3 mg/m2 given i.v. on day 1; treatment repeated every 3 weeks). In 64 evaluable patients, the objective response rate was 37% (complete responses, 4.7%; partial responses, 32.3%). The median survival was 7.6 months for all patients. The treatment was very well tolerated. MEV proved to be an active and non-toxic regimen for the treatment of metastatic NSCLC.

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Second- and third-harmonic generation as a local probe for nanocrystal-doped polymer materials with a suppressed optical breakdown threshold

Abstract Second- and third-harmonic generation processes are shown to allow the detection of absorptive agglomerates of nanocrystals in transparent materials and the visualization of optical breakdown in nanocomposite materials. Correlations between laser-induced breakdown and the behavior of the second- and third-harmonic signals produced in SiC/PMMA nanocomposite films are studied. The potential of second- and third-harmonic generation for the on-line visualization of laser breakdown in nanocomposite polymer materials is revealed, with the ablative material removal being monitored by the decay of the second- and third-harmonic signals. The second and third harmonics generated around the o…

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SINDROME DA ATTIVAZIONE MACROFAGICA SECONDARIA AD IMMUNODEFICIT

Introduzione: la sindrome da attivazione macrofagica (SAM) è una condizione clinica rara, di cui esistono forme primitive (es. deficit di perforine) e secondarie ad infezioni, farmaci, immunodeficit; nel 10% dei casi rappresenta una complicanza dell'artrite idiopatica giovanile sistemica (AIG). Criteri diagnostici: febbre, epatosplenomegalia, citopenia bilineare, aumento di ferritina, transaminasi, ipertrigliceridemia ed ipofibrinogenemia con segni di emofagocitosi all'aspirato midollare. Terapia: metilprednisolone a 30 mg/Kg/die ev e terapia della patologia di base; nei no-responders trova impiego l'uso dei farmaci immunosoppressori come ciclosporina, Anakinra per forme secondarie ad AIG, …

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Parameter identification of induction motor model using genetic algorithms

The paper deals with methods of identification of the parameters of an induction motor model using genetic algorithms. It is supposed that the inverter supplying the motor is directly accessible for control of the conduction sequences of its power switches. This makes it possible to carry out a test consisting of a transient from standstill to steady-state operation at a given frequency and successive free motion to standstill. During this test, data are acquired referring to stator voltages, and currents and speed. Then, a genetic algorithm is employed with the aim of determining the mechanical and electrical parameters of the model, so as to reproduce the input-output behaviour of a real …

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Amplification of nonlinear currents generation at harmonics frequencies of submillimeter radiation

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