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Objectives: To evaluate the incidence and the time of onset of early micro-embolism after CAS (carotid artery stenting) with two different mesh-covered stents and to assess the role of DW-MRI (Diffusion-weighted magnetic resonance imaging) in their prediction.Methods: Single-institution prospective study including 50 patients (33 male, median age 74 years) who underwent CAS with Roadsaver® or CGuard™. All patients with primary stenosis (37/50, 74%) had carotid plaque DW-MRI pre-procedure, with both qualitative evaluation of the hyperintensity and ADC (apparent diffusion coefficient) measurement of the plaque. All patients had brain DW-MRI pre-procedure, at 1 h, 24 h and 30 days post-procedure to evaluate the appearance of hyperintense lesions over time. Imaging analysis was performed in a double-blinded fashion by two radiologists.Results: There were no statistically significant differences between the two stents both in the incidence at 1 h (P = 0.23) and 24 h (P = 0.36) and in the volume of new DWI hyperintense brain lesions at 24 h (P = 0.27). Thirty-four new asymptomatic lesions in 19 patients (38%) were reported: 4 (11.8%) at 1 h, 30 (88.2%) at 24 h. The 30-day DWI-MR showed complete resolution of all lesions and no evidence of new lesion. The incidence of new lesions at 24 h resulted significantly higher in patients with DWI hyperintense carotid plaques (12/16, 75% vs. 0/21, 0%, P < 0.0001). This result was paralleled by the difference in ADC value (0.83 ± 0.21 vs. 1.42 ± 0.52).Conclusion: The majority of early asymptomatic brain lesion occurred during the first 24 h after CAS. Pre-procedure high DWI signal of the plaque was associated with an increased incidence of post-procedure microembolizations. [ABSTRACT FROM AUTHOR]

Purpose: To relate the multiparametric magnetic resonance imaging (mp-MRI) of patients with suspect peripheral prostate cancer (PCa) to the results of the subsequent biopsy: in particular to explore whether DWI and ADC can predict the biopsy outcome and to investigate the relation between ADC and Gleason score (GS). Materials and methods: 175 consecutive patients who underwent 1.5 T mp-MRI followed by prostate biopsy were retrospectively analyzed by two independent radiologists. ADC values were measured in the peripheral suspect lesion areas (ADC) and in the contralateral zones (ADC) obtaining ADC = ADC/ADC. Results on T2W images, DWI, ADC values, and perfusion studies were matched to their corresponding biopsy. Results: Negative DWI and T2W had 100% negative predictive value (NPV). When DWI was positive, ADC > 0.90 × 10 > 0.90 × 10 mm/s (ADC > 0.60) identified by the ROC curve (AUC = 0.80) corresponded to NPV = 85%. In positive biopsies, ADC and ADC decreased significantly from GS = 6 to GS ≥ 8 with Spearman coefficient ρ = −0.40 and ROC curve AUC = 0.72. Conclusion: mp-MRI allows a reliable prediction of a negative biopsy through the values of DWI, T2W, and ADC. In positive biopsies, there is a moderate correlation between ADC and the various GS levels. [ABSTRACT FROM AUTHOR]

Estimates of solute and solvent changes during electrolyte abnormalities are valid only when either total body water (TBW) or solute content do not change, while it cannot be established which one of these is altered. The present paper provides a method capable of distinguishing these two different conditions. When only solvent changes, the respective concentration ratios of plasma (P) solutes PCl/PNa, POAN: /PNa, PCl/POAN: (POAN: = anions other than Cl) remain unchanged. Moreover, PNa(1)/PNa(0) (the ratio of PNa during the derangement over the normal value, indicated by subfix (1) and (0), respectively) = PCl(1)/PCl(0) = POAN: (1)/POAN: (0.) When these constraints are met, the abnormality is due only to a TBW change, which is easily calculated and corrected. When they are not met, the exact change in Na content is correctly calculated assuming no variation in TBW. These calculations could still be useful even in the presence of TBW modifications, where they represent minimum estimates of electrolyte losses. The formulas were validated by computer simulations generating true electrolyte concentrations, which were then used to back calculate the changes in their contents and extra/intra-cellular volumes. Since the predicted results were significantly correlated with the true data, the method was transferred to 24 patients with electrolyte disturbances, who met the above constraints. The calculated volume changes were significantly correlated with those obtained by body weight measurements (regression coefficient = 0.94, P < 0.0001), while the quantitative estimates of Na deficit predicted the PNa values measured after corrective treatment (P < 0.0001). This new method may prove valuable in diagnosing and treating electrolyte derangements. [ABSTRACT FROM AUTHOR]

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Copyright of Il Nuovo Cimento: B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We present the first results of the combined measurements of the EAS-TOP (at the surface) and LVD (deep underground) detectors operating as a combined telescope in the study of UHE cosmic rays and their interactions. Examples of different classes of events and their significance in different high-energy and astrophysical studies are discussed. [ABSTRACT FROM AUTHOR]

We present the first results of the observations of the atmospheric Cherenkov light emission from Extensive Air Showers, obtained from the EAS-TOP experiment at Campo Imperatore (at the Gran Sasso Laboratory). Data concern measurements at low energies, and the correlations with the e.m. and GeV muon detectors at the surface, and with the events observed deep underground (LVD detector). [ABSTRACT FROM AUTHOR]

The Large Volume Detector (LVD) in the Gran Sasso underground Laboratory is a multipurpose detector consisting of a large volume of liquid scintillator interleaved with limited streamer tubes. In this paper we discuss its power to study low-energy cosmic neutrinos. The results show that the first LVD tower (368 tons of liquid scintillator) is well suited to detect neutrinos from gravitational stellar collapses within all of our Galaxy over a wide range of burst duration (up to a few hundred seconds). No burst candidates have been observed in the first two months of data taking. [ABSTRACT FROM AUTHOR]

We have conducted a preliminary spectral analysis of large-amplitude internal solitons in the Andaman Sea. Our methods are based upon the spectral (or scattering) transform solution of the Korteweg-de Vries equation. [ABSTRACT FROM AUTHOR]

We study nonlinear interactions in measured surface wave trains obtained in the Northern Adriatic Sea about 16 kilometres from Venice, Italy. Nonlinear Fourier analysis is discussed in terms of the exact spectral solution to the Korteweg-deVries (KdV) equation as given by the inverse scattering transform (IST). For the periodic and/or quasi-periodic boundary conditions assumed herein, the approach may be viewed as a nonlinear, broad-banded generalization of the ordinary, linear Fourier transform. In particular, we study solition interactions, their properties and the nonlinear dynamics of the radiation (or oscillation) modes as found from the inverse scattering transform analysis. We also conduct a number of computer experiments in which measured wave trains are numerically propagated forward in time toward shallow water and backward in time into deep water in order to assess how the nonlinear wave dynamics are influenced by propagation over variable bathymetry. On this basis we develop a scenario for the evolution of nonlinear wave trains, initially far offshore in deep water, as they propagate into shallow water regions. The deep-water waves have a small Ursell number and are hence not very nonlinear; as they propagate toward shallow water, the Ursell number gradually increases in the numerical experiments by about an order of magnitude. A useful parameterization of nonlinearity in these studies is the «spectral modulus,» a number between 0 and 1, which is associated with each IST spectral frequency. Small values of the modulus mean that a particular spectral component is linear (a sine wave); large values of the modulus (≈1) indicate that the component is nonlinear (a soliton). There is a systematic increase of the modulus as the waves propagate into shallow water where nonlinear effects predominate; we describe how the modulus varies as a function of spectral frequency during this shoaling process. The results suggest that the effect of increasing nonlinearity «saturates» the IST spectrum ( i.e. the modulus ≈1 for all frequencies) to that virtually all spectral components become solitons in sufficiently shallow water. [ABSTRACT FROM AUTHOR]

We outline here the logical flow of papers that attack the problem of estimating the wave conditions in front of and at the Venetian littoral. We start from the determination of the wind fields, followed by that of the wave fields. The wave data are then transferred to the coast. We end by analysing the wave conditions inside the main inlet to the Venice lagoon. This paper gives a brief account of the logical flow of arguments from paper to paper, indicating the main results and outlining the robust structure of the overall research. We end with a discussion on the accuracy of the results, and with an indication of the possible lines for further research. [ABSTRACT FROM AUTHOR]

Extensive Air Shower (EAS) experiments with high granularity have reported the detection of multicore events. On the other hand, multicluster and double-core events have been observed with emulsion chambers (EC) at mountain altitudes since the late '70s. A striking characteristic of these events is the large transverse momentum of the clusters. At accelerator energy region, it is known that jet production in deep inelastic hadronic processes is associated with the emission of large- P particles. In this paper we analyse the possibility that both EAS and EC events represent the same physical process, discussing the physical consequences of this fact and the possibilities offered by both techniques in integrating the accelerators data. [ABSTRACT FROM AUTHOR]

We report the results of four laboratory experiments on surface water waves generated with the Pierson-Moskowitz power spectrum, and characterized by different values of the ratio f / f and of the water depth h. The scope of the experiments was to test the dependence of the chaotic and fractal properties of the data on the parameter f / f , which has been indicated as determinant by previous numerical studies; the different water depths are used to induce different levels of non-linearity in the records. The analysis indicates that the Grassberger and Procaccia correlation integrals, the largest Lyapunov exponent and the scaling exponent of the data sets considered herein are completely assimilable to those of numerically generated linear time series; the algorithms used are insensitive to the presence of non-linearities because they sample essentially the high-frequency components. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of high-frequency filtering the background white noise on the determination of the coloured-random-noise properties of cosmic-ray experimental signals. We consider fractal methods (Grassberger-Procaccia method, scaling exponent method and fractal length method) and statistical methods (comparison with the Gaussian curve, and the multivariate scaling-analysis technique). The investigation is carried out using two experimental time series with different colour (spectral indices α=1.6 and α=1.2) and their computer simulations of pure noise-free coloured-random-noise signals. The results of the investigation is that the use of high-frequency filtering allows the algorithms employed in the various analyses to see the physical characteristics of the particular data set; the procedure should be reserved, however, to researchers with a good experience in the methods of fractal analysis so that they can identify and discard the artifacts introduced by the truncation applied to the power spectrum. [ABSTRACT FROM AUTHOR]

The study of extensive air showers is performed at EAS-TOP by means of the combined operation of the first imaging Čerenkov telescope and the particle e.m. array. We discuss the technical characteristics of the Čerenkov detector and its resolutions. First data on the shape of the Čerenkov-light spots as a function of the EAS detection geometry, and on a first approach to the study of the longitudinal development of the cascades are also presented. [ABSTRACT FROM AUTHOR]

The muon-hadron detector of EAS-TOP is a 270 m calorimeter constructed inside the air shower array on the top of the underground Gran Sasso Laboratory (Italy). The general layout of the detector and the performances of the active part (streamer and proportional chambers) are presented. [ABSTRACT FROM AUTHOR]

The EAS-TOP Extensive Air Shower array, on top of the under-ground Gran Sasso Laboratory, is fully operating as a γ-ray astronomy observatory since the beginning of 1989. After showing the measured angular resolution of the detector, we present the results obtained from the analysis of 280 days of measurements in 1989-1990, with the purpose of investigating possible emission (d.c. and sporadic) from the candidate sources in the Northern hemisphere at an energy, >200 TeV. [ABSTRACT FROM AUTHOR]

First results on the lateral and temporal structures of EAS obtained from the EAS-TOP array are presented. A correlation between the slope of the lateral distribution function and the time delay of EAS particles with respect to the shower front at fixed core distance is found and discussed. [ABSTRACT FROM AUTHOR]

A search for cosmic gamma-ray bursts in the GeV energy range has been performed by means of the EAS-TOP Extensive Air Shower array at Campo Imperatore (Gran Sasso Laboratories) during the period March-December 1990. In 2566.5 hours of measurement the obtained upper limit to the rate of bursts of amplitude >2% of the cosmic-ray intensity and time duration τ=1 s, is R≤7.9y (90% c.l.). Assuming for γ-rays a differential energy spectrum S(E )≈E , the corresponding upper limit to the energy flux of γ-rays with energy >5 GeV in bursts of duration τ≤1 s is Φ<8.3·10erg cm. [ABSTRACT FROM AUTHOR]

Images of atmospheric EAS Cherenkov light have been recorded in connection with the EAS-TOP experiment. We describe the technique (based on a multianode photomultiplier Philips XP4702) and present some preliminary data analysis. [ABSTRACT FROM AUTHOR]

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Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: C is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento: B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Il Nuovo Cimento della Societa Italiana di Fisica: B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)