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The present work follows the trend to develop non-aqueous electrolytes for the deposition of corrosion resistant ZnNi alloys. It investigates the use of the choline chloride/ethylene glycol (1:2 molar ratio) eutectic mixture and of pure ethylene glycol as solvents for ZnNi electroplating. The electrochemical behavior of Zn and Ni is investigated via cyclic voltammetry, and potentiostatic ZnNi deposition is performed. Ni content is found to be precisely tunable in the 10–20% wt range, which presents the highest industrial interest for corrosion protection. ZnNi coatings obtained are characterized from the morphological and phase composition point of view. Evidence of the formation of a metastable γ ZnNi phase is observed for both choline chloride/ethylene glycol and pure ethylene glycol. Finally, potentiodynamic corrosion tests are performed to assess their corrosion properties.

A statistical thermodynamic approximation for cooperative phenomena in Ising and Heisemberg systems has been developed. Description of order-disorder transformation in alloys as well as evaluation of the magnetic contribution for the free energy of ferromagnets is provided with this approach. The constant coupling approximation is improved by introducing a second pairs reactions after averaging atomic groups, on the analogy of block construction in renormalization group techniques. Temperature variation after renormalizing is taken into account by two suitable temperature functions. As analytic expression for the system free energy is obtained which gives well approximate thermodynamic quantities (order parameter, internal energy, specific heat). In particular, the critical behaviour is properly described, with accurate thermodynamic quantities and right exponents. This approach has been applied to real system, showing what are the differences with ideal Ising system. In order-disorder alloys like β-brass, order parameter and specific heat as a function of temperature are obtained and ordering phenomena are discussed.

Carbide coatings deposited by PVD techniques can provide different properties according to their structural and compositional features. In particular, MC/a-C(:H) composite coatings (where M is a carbide-forming element) receive increasing attention as wear resistant films with low coefficient of friction. In this work, Ti-C:H coatings were prepared by reactive magnetron sputtering and their atomic ratio Ti/C was varied between 0.14 and 5.3. Maximum hardness values were achieved for Ti/C ratios corresponding to the carbide formation. Nanocomposite coatings with hydrocarbon matrix were deposited after growing a functionally graded interlayer and their tribological properties were investigated both in air and in water.

Stereotactic placement of intracerebral multilead electrodes for chronic EEG recording of seizures or stereoelectroencephalography (SEEG) was introduced 50 years ago at Saint Anne Hospital in Paris, France for the presurgical evaluation of patients with drug-resistant focal epilepsy. SEEG explorations are indicated whenever the noninvasive tests fail to adequately localize the epileptogenic zone (EZ).Currently, approximately 35% of our operated-on children require a SEEG evaluation. Arrangement of electrodes is individualized according to the peculiar needs of each child, to verify a predetermined hypothesis of localization of the EZ based on pre-SEEG anatomo-electro-clinical findings. Multilead intracerebral electrodes are designed to sample cortical structures on the lateral, intermediate, and mesial aspect of the hemisphere, as well as deep-seated lesions. Stereotactic stereoscopic teleangiograms and coregistered 3-D MRI are employed to plan avascular trajectories and to accurately target the desired structures. Pre-SEEG stereotactic neuroradiology and electrode implantation are usually performed in separate procedures. Electrodes are removed once video-SEEG monitoring is completed.Intracerebral electrical stimulations are used to better define the EZ and to obtain a detailed functional mapping of critical cortical and subcortical regions.Surgical morbidity of SEEG is definitely low in children.In 90% of evaluated children, SEEG provides a guide for extratemporal or multilobar resections. SEEG-guided resective surgery may yield excellent results on seizures with 60% of patients in Engel’s Class I.

Sleep-related hyperkinetic seizures are a common feature of nocturnal frontal lobe epilepsy. Although sleep-related seizures with a temporal lobe origin have been reported, they commonly lack hyperkinetic activity. The authors describe three patients with sleep-related seizures characterized by frenetic, agitated, hyperactive movements (bimanual/bipedal activity, rocking, axial, pelvic, and hemiballistic movements), in whom stereo-EEG investigation and surgical outcome demonstrated a temporal lobe origin of the attacks.

To evaluate the contributing role of sleepiness in Italian highway vehicle accidents during the time span 1993-1997.

We suggest a simple thermal Comptonization model to account for theobserved phase lags-hardness ratio correlation of GRS1915+105.

Introduction: In order to define accurately the relationship between EEG components (spindles, delta and theta frequencies) and the occurrence of interictal epileptiform discharges (IED) during sleep in partial epilepsy, a correlation study between spike overnight distribution and EEG spectral power time series was performed.

A method for the automatic detection of arousals in digital polysomnographic recordings is described. The computer program analyzed two EEG and one EMG derivations marking variable length segments as arousals. The processing of EEG data started from the wavelet transform, which characterizes the signal in the time-frequency domain, and resulted in a set of indices used to discriminate possible arousal segments. Transient increases in muscle activity were also identified, while a multichannel and context sensitive analysis allowed arousal detection. Out of 11 overnight recordings, 3 were used as the training set and 8 as the program testing set. In the first stage of the study two EEG experts inspected the tracings independently to score arousals. They then reviewed all recordings and jointly examined each event for validation, both those scored by themselves and those scored by the computer. A reference set of definite arousals (1125 in the testing set) and a number of uncertain events (266) were thus obtained. The sensitivity of the automatic system (88.1%) was higher than that of the human experts (72.4 and 78.4%) while the selectivity was lower (74.5% for the automatic system, 83.0 and 82.0% for the experts). This suggested that automatic detection, followed by an expert's validation, may render the analysis of arousals more widely feasible as well as support the study of arousal features.

The expression of beta 1 (very late activation antigens, VLA 1–6) and beta 2 integrins (leukocyte adhesion molecules [Leu-CAM]) in cell suspensions from the peripheral blood of 70 patients with B-cell chronic lymphocytic leukemia (B-CLL), 15 patients with leukemic lymphocytic lymphoma of intermediate differentiation (IDL), as well as from the lymph nodes of 20 patients with low/intermediate-grade non- Hodgkin's lymphoma (NHL) was studied with the aim of characterizing their adhesive phenotype and evaluating its relationship to clinical behavior. CD11a(LFA-1) was more expressed in NHL and IDL than in B-CLL (P = .047), although it was demonstrable in 74.2% of cases; CD11c was more expressed in B-CLL (P less than .0001), and its expression was preserved in almost all of the cases of small lymphocytic lymphoma. In NHL patients, including the cases of IDL, VLA-3 expression was observable in 8 of 35 cases (although always at a low level of intensity), while VLA-4 was almost constantly expressed in a way that was similar to its expression in control normal B cells. On the contrary, in B-CLL patients, VLA-3 was expressed (prevalently at high levels) in 87.1% of cases and VLA-4 only in 37.1%. No correlation was found between adhesion molecule patterns and the clinical features of the diseases. The biofunctional significance of the imbalance of VLA-3 and VLA-4 expression in B-CLL is not easy to explain, but it has undoubted intrinsic value as an additional marker for distinguishing B- CLL from, in particular, those B-cell neoplasms (such as IDL) that share many of the immunocytomorphologic characteristics and the putative normal counterpart (the mantle zone) of B-CLL.

We describe a model for SS 433 based on an accretion disk around a black hole. Due to the very high mass transfer rate in the system, the disk must be geometrically thick. Two narrow funnels are formed around the rotation axis and radiation pressure in the funnels accelerates matter to relativistic velocities in the form of two opposite jets. TheX and optical luminosities are evaluated and they agree well with the experimental data.

The geodesic properties of a spinning naked singularity are analysed to achieve a better understanding about its nature. Repulsive phenomena are shown to exist and are interpreted in a way which preserves the attractive character of gravitation. Si analizzano le proprietà geodetiche di una singolarità osservabile ruotante con lo scopo di giungere ad una maggior comprensione della sua natura. Si mette in evidenza l'esistenza di fenomeni repulsivi, che sono interpretati in modo tale da confermare il carattere attrattivo della gravità. Проводится анализ геодезических свойств явной сингулярности вращения, чтобы довиться лучшего понимания природы этой сингулярности. Показывается, что существуют явления отталкивания. Предлагается интерпретация этих явлений, в которой сохраняется притягивающий характер гравитации.

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We present new counts of stars in M15, using plates inB, V andU. We are able to explore relatively close to the central parts of the cluster (0.1 pc) and we derive the best fitting parameters for the star distribution.

Isolated splenic hairy cells from three untreated patients were cultured in presence of recombinant human interferon alpha-2C (IFN alpha). Ultrastructural cytochemistry and immunophenotype analysis with a large panel of monoclonal antibodies were performed to study cellular modification induced by IFN alpha. Hairy cells showed a typical pheno- type: Smlg+, B1+, BA1+/-, anti-Tac+, OKDR+, Leu-M5+, HC2+, TRAP+, myeloperoxidase-. Under our experimental conditions, we found no direct cytotoxic effects or significant variations in morphology, cytochemistry, and percentage of reactivity with the tested monoclonal antibodies. After culturing in the presence of different doses of IFN alpha, we observed a significant enhancement of the expression of class II HLA antigens as demonstrated by increased fluorescence for OKDR, OKla, Leu-10 at fluorescence-activated cell sorting analysis. In agreement with this finding IFN alpha-treated hairy cells showed an increased stimulatory capacity v allogeneic T cells in one-way mixed lymphocyte reaction. To our knowledge this is the first report describing the induction of class II HLA antigens on hairy cells by IFN alpha.

Isolated splenic hairy cells from three untreated patients were cultured in presence of recombinant human interferon alpha-2C (IFN alpha). Ultrastructural cytochemistry and immunophenotype analysis with a large panel of monoclonal antibodies were performed to study cellular modification induced by IFN alpha. Hairy cells showed a typical pheno- type: Smlg+, B1+, BA1+/-, anti-Tac+, OKDR+, Leu-M5+, HC2+, TRAP+, myeloperoxidase-. Under our experimental conditions, we found no direct cytotoxic effects or significant variations in morphology, cytochemistry, and percentage of reactivity with the tested monoclonal antibodies. After culturing in the presence of different doses of IFN alpha, we observed a significant enhancement of the expression of class II HLA antigens as demonstrated by increased fluorescence for OKDR, OKla, Leu-10 at fluorescence-activated cell sorting analysis. In agreement with this finding IFN alpha-treated hairy cells showed an increased stimulatory capacity v allogeneic T cells in one-way mixed lymphocyte reaction. To our knowledge this is the first report describing the induction of class II HLA antigens on hairy cells by IFN alpha.

A general expression of heat and momentum exchange in an optically thin gas due to Compton process is here given, by considering also the lowest-order corrections from relativistic quantum electrodynamics. The relevance to the problem of astrophysical jets is discussed.

We study the evolution of a naked singularity surrounded by an accreting disk of matter; we consider two kinds of disk: the standard thin-disk model and the thick barytropic model, for several initial conditions. We show that any Kerr naked singularity slows down in a finite time to a maximal Kerr black hole. We evaluate the final mass, the luminosity and the time of evolution of the singularity.

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Background:Sleep-related hypermotor epilepsy (SHE) is a focal epilepsy characterized by abrupt sleep-related hypermotor seizures (SRHS) with complex semiology. Although difficult to localize within the frontal lobe recent studies using intracerebral EEG recordings have suggested the existence of four distinct semiology patterns (SP) organized in a rostro-caudal manner. It remains unclear however if these SP are clinically useful. Methods:We aimed to estimate the inter-rater reliability (IR) of classifying SP in SHE amongst epilepsy and sleep medicine experts. Following a short training session, ten experts were asked to review and classify 40 videos of SRHS in patients with confirmed SHE. IR was calculated using Kappa statistics. Results:SP1 and SP4, who are at the opposite ends of the SHE semiology spectrum, had substantial IR (0.82 and 0.67, respectively). Meanwhile, SP2 and SP3 showed fair agreement (0.25 and 0.35, respectively) and represented the major source of variance, with a small difference favouring epilepsy experts. Conclusions:Amongst epilepsy and sleep medicine experts, IR of classifying SRHS into four SP was only mildly satisfactory. SP1 and SP4 were shown to be easily recognizable while SP2 and SP3 were frequently confounded. Improvements in SP recognition are needed before widespread clinical use.

Ruthenium is electrodeposited for the first time from a deep eutectic solvent based electrolyte composed of ethylene glycol and choline chloride in 1:2 molar ratio. Deposition is found to effectively occur upon addition of sulfamic acid to the Ru(III) containing deep eutectic solvent. The main consequence of the presence of sulfamic acid, as evidenced by the electrochemical characterization performed, is the oxidation of Ru(III) to Ru(IV). Consequently, Ru electroreduction is demonstrated to take place from the tetravalent state. Optimized plating conditions are able to yield uniform and crack-free Ru coatings up to 800 nm thickness. No oxides or other notable secondary phases can be individuated in the obtained metallic layers. Morphological and electrical properties of the layers obtained are comparable with Ru coatings deposited from sputtering and suggest possible applications in the electronics field as barrier layers for interdiffusion.