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Background: Italy is a high-risk area for multiple sclerosis with 110,000 prevalent cases estimated at January 2016 and 3400 annual incident cases. To study multiple sclerosis epidemiology, it is preferable to use population-based studies, e.g., with a registry. A valid alternative to obtain data on entire population is from administrative sources.Objective: To estimate the incidence of multiple sclerosis in Tuscany using a case-finding algorithm based on administrative data.Methods: In a previous study, we calculated the prevalence in Tuscany using a validated case-finding algorithm based on administrative data. Incident cases were identified as a subset of prevalent cases among those patients not traced in the years before the analysis period, and the date of the first multiple sclerosis-related claim was considered the incidence date of multiple sclerosis diagnosis. We examined the period 2011-2015.Results: We identified 1147 incident cases with annual rates ranged from 5.60 per 100,000 in 2011 to 6.58 in 2015.Conclusions: We found a high incidence rate, similarly to other Italian areas, especially in women, that may explain the increasing prevalence in Tuscany. To confirm this data and to calculate the possible bias caused by our inclusion method, we will validate our algorithm for incident cases. [ABSTRACT FROM AUTHOR]

We provide an overview on terahertz (THz) frequency metrology, starting from the nowadays available continuous wave THz sources, discussing their main features such as tunability, spectral purity, and frequency referencing to the primary frequency standards. A comparison on the achieved results in high-precision molecular spectroscopy is given and discussed, and finally, a special emphasis poses on the future developments of this upcoming field. [ABSTRACT FROM AUTHOR]

Summary: Mainly driven by the recent dramatic progress of infrared technologies, as well as by the emerging methods for cooling of ground-state molecules, the field of precision molecular spectroscopy is experiencing a new youth, as it promises to lead major advances both in fundamental and applied science. The present review will encompass the main results obtained in the last two decades, by our group, in this scope, particularly in the mid infrared and THz spectral regions. Starting from the development of novel, metrological-grade coherent radiation sources, either in continuous-wave or in pulsed-emission regime, we will go through the realization of more an more sophisticated spectroscopic interrogation techniques. We will then conclude with the first demonstration of cavity-enhanced ro-vibrational spectroscopy on a buffer-gas-cooled molecular beam. From this brief overview it emerges that high-precision physical fundamental measurements can be done, at present, at an energy scale as low as the photons used for harnessing the molecular samples. [ABSTRACT FROM AUTHOR]

We report on recent development of IR spectrometers based on non-linear optical generation and quantum-cascade lasers. Frequency stabilization and referencing to optical frequency-comb synthesizers is described. Their characteristics for spectroscopic as well as metrological applications are pointed out. The potential of the combination of mid-IR sources with enhancement cavities for high-resolution and sensitive measurements of gas spectra is illustrated. Finally, we describe wave-front engineering of long wavelength beams for spatial control and imaging applications. [ABSTRACT FROM AUTHOR]

In this paper we investigate the performance of quantum cascade (QC) lasers for high frequency modulation spectroscopy, particularly using frequency modulation (FM) and two-tone (2T) techniques. The coupling of the rf signal to the QC laser through the cryostat is studied in detail as well as the noise contributions of both the detector and the laser source to the final spectra. The experimental traces are obtained by spectroscopy on low-pressure N2O and CH4 gases at 8.0 μm and 7.3 μm wavelength, respectively, and reproduce the line profiles predicted by theory. As a preliminary result, an enhancement of a factor six is measured with respect to direct absorption line recording. [ABSTRACT FROM AUTHOR]

We present an experimental study of the dynamics of a magneto–optical trap (MOT) loaded from an alkali dispenser current controlled source. In our experimental vacuum conditions and for a low trapping force MOT the trap loading process critically depends on the dispensers working regime. This allows to completely characterize the dispensers–MOT system and to determine the best loading conditions. [ABSTRACT FROM AUTHOR]

We present the results of an experiment on light scattering from an elongated Bose-Einstein condensate interacting with far off resonant laser light. Due to superradiant Rayleigh scattering a coherent superposition of two atomic wavepackets with different momenta forms in the presence of a single laser beam. Varying the intensity of a weak counterpropagating laser beam we observe the transition from the pure superradiant regime to the Bragg scattering regime, where Rabi oscillations in a two-level system are observed. The process is limited by the decoherence between the two atomic wavepackets. [ABSTRACT FROM AUTHOR]