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The article presents the case study of a 27 year old woman at 21 weeks’ gestation. Fetal echocardiography revealed multiple cardiac rhabdomyomas, with the largest lesion in the left ventricle Neurosonography and fetal magnetic resonance imaging demonstrated cerebral tubers. The kidneys appeared normal. Fetal tuberous sclerosis was suspected,

We have used laser pulses with a temporally shaped polarization to demonstrate the multiphoton excitation of the xenon 5g state within a subcycle of a laser pulse. Our polarization gated laser pulses are composed of circularly polarized sections at the leading and trailing edges of the pulse and of an experimentally defined linearly polarized central part. Only the linear part (the gate) of the pulse can excite neutral xenon in the 5g state. The transition cannot be driven with circularly polarized light because the number of photons needed would cause a violation of selection rules for the change of the magnetic quantum number. We show that the linearly polarized central part can be reduced to a subcycle pulse. This allows us to study excitation with an effective pulse as short as 2.3 fs at 800 nm. Electron imaging spectroscopy has been used to visualize the presence of excited states as a function of the pulse duration of the gate. [ABSTRACT FROM AUTHOR]

This is a review of some recent development in femtosecond filamentation science with emphasis on our collective work. Previously reviewed work in the field will not be discussed. We thus start with a very brief description of the fundamental physics of single filamentation of powerful femtosecond laser pulses in air. Intensity clamping is emphasized. One consequence is that the peak intensity inside one or more filaments would not increase significantly even if one focuses the pulse at very high peak power even up to the peta-watt level. Another is that the clamped intensity is independent of pressure. One interesting outcome of the high intensity inside a filament is filament fusion which comes from the nonlinear change of index of refraction inside the filament leading to cross beam focusing. Because of the high intensity inside the filament, one can envisage nonlinear phenomena taking place inside a filament such as a new type of Raman red shift and the generation of very broad band supercontinuum into the infrared through four-wave-mixing. This is what we call by filamentation nonlinear optics. It includes also terahertz generation from inside the filament. The latter is discussed separately because of its special importance to those working in the field of safety and security in recent years. When the filamenting pulse is linearly polarized, the isotropic nature of air becomes birefringent both electronically (instantaneous) and through molecular wave packet rotation and revival (delayed). Such birefringence is discussed in detailed. Because, in principle, a filament can be projected to a long distance in air, applications to pollution measurement as well as other atmospheric science could be earned out. We call this filamentation atmospheric science. Thus, the following subjects are discussed briefly, namely, lightning control, rain making, remote measurement of electric field, microwave guidance and remote sensing of pollutants. A discussion on the higher order Kerr effect on the physics of filamentation is also given. This is a new hot subject of current debate. This review ends on giving our view of the prospect of progress of this field of filamentation in the future. We believe it hinges upon the development of the laser technology based upon the physical understanding of filamentation and on the reduction in price of the laser system. [ABSTRACT FROM AUTHOR]

We observed a new filamentation nonlinear process: continuous self-frequency down shift inside the filament zone during the propagation of a femtosecond laser pulse in air. The frequency shift depends strongly on the length of the self-guided column (filament). [ABSTRACT FROM AUTHOR]

This study investigated the level of resistance and the level of muscle activation of the prone back exercise. Fifteen male subjects with no previous history of low back injury performed two repetitions of seven exercises. These consisted of four maximal isometric voluntary contractions (MVC) and three prone back extension (PBE) exercises. The subject was lying prone on a table, the upper body was suspended off the end of the table and the legs and thighs were secured to the table with straps. Three starting positions from the horizontal were investigated. 0.30° and 60°, and were compared with MVC to quantify the level of effort needed to perform the task. The results showed that the three PBE exercises require a level of resistance and a level of muscle activation generally under 40° of the maximum capacity of healthy subjects. Muscle activity of the erector spinae (ES) was slightly greater when the exercise started at 60° compared to 0° and 30°. During the static phase of the PBE exercises, the level of resistance remained at 40° relative to the peak reaction moment of the MVC, but muscular activity of ES tended to work at a lower activity level. In conclusion, since for healthy subjects PBE exercises are low resistance exercises, they seem to be more specifically designed to develop muscular endurance of the back muscles. [ABSTRACT FROM AUTHOR]

The authors report on an approach for simultaneous monitoring of multigas pollutants based on fluorescence emission of trace gases, induced by the filamentation of intense femtosecond laser pulses in air. The high intensity inside a filament can dissociate the gas molecules into small fragments which emit characteristic fluorescence. This method is illustrated for simultaneously sensing atmospheric trace gases, methane and acetylene. The spectra of an “unknown” mixture were analyzed by using a genetic algorithm, showing good concentration agreement with the experimental results within an error of 25%. [ABSTRACT FROM AUTHOR]

Rhabdomyomas are the most common fetal cardiac tumours, often associated with tuberous sclerosis. Neonatal treatment for symptomatic rhabdomyomas previously described, include surgical debulking, stenting, anti-arrhythmic therapy and mammalian target of rapamycin (mTOR) inhibition. We document the antenatal use of sirolimus for the treatment of a large fetal rhabdomyoma causing ventricular dysfunction and pericardial effusion at 31 weeks of gestation. [Extracted from the article]

An abstract of the article "The role of prior uterine closure on the lower uterine segment thickness measurement: A multicentre prospective study" by C. Vachon Marceau and others is presented.

Abstract: The mobile femtosecond laser facility T&T (terawatt & terahertz) of DRDC-Valcartier was used to detect trace methane gas remotely in an open field atmosphere during daytime (with strong sun light) using filament-induced fluorescence spectroscopy. Comparison of the results obtained in the laboratory and in the field validates the long range extrapolations of short distance results taken in our laboratory in the past. This could be considered a breakthrough for remote sensing based on filamentation. [Copyright &y& Elsevier]