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Le Touquet – Paris-Plage, France

Ravel C.,Service de Biologie de la Reproduction | Hyon C.,University Paris VI | Hyon C.,French Institute of Health and Medical Research | Siffroi J.-P.,University Paris VI | And 3 more authors.
Annales d'Endocrinologie | Year: 2014

DAX-1 stands for Dosage sensitive sex-reversal, Adrenal hypoplasia congenital (AHC), on the X chromosome. DAX-1 mutations usually cause primary adrenal insufficiency or congenital adrenal hypoplasia in early childhood and hypogonadotropic hypogonadism (MIM # 300200). DAX-1 protein is necessary to maintain normal spermatogenesis. In humans, male fertility has been studied in few patients carrying DAX-1 mutations. Cases of azoospermia have been reported, as well as unsuccessful gonadotropin treatments. The clinician should be informed that TESE-ICSI technique carries a potential hope to father non-affected children, as shown in this review. © 2014 . Source

Gonzalez-Galindo F.,Institute Astrofisica Of Andalucia | Chaufray J.-Y.,University Paris - Sud | Lopez-Valverde M.A.,Institute Astrofisica Of Andalucia | Gilli G.,Institute Astrofisica Of Andalucia | And 5 more authors.
Journal of Geophysical Research E: Planets | Year: 2013

We describe the Mars ionosphere with unprecedented detail in 3-D, as simulated by a Mars general circulation model (the Laboratoire de Météorologie Dynamique Mars GCM), and compare it with recent measurements. The model includes a number of recent extensions and improvements. Different simulations for a full Martian year have been performed. The electron density at the main ionospheric peak is shown to vary with the Sun-Mars distance and with the solar variability, both in the long-term (11 year solar cycle) and on shorter temporal scales (solar rotation). The main electronic peak is shown to be located at the same pressure level during all the Martian year. As a consequence, its altitude varies with latitude, local time, and season according to the natural expansions and fluctuations of the neutral atmosphere, in agreement with previous models. The model predicts a nighttime ionosphere due only to photochemistry. The simulated ionosphere close to the evening terminator is in agreement with observations. No effort has been made to explain the patchy ionosphere observed in the deep nightside. We have compared the modeled ionosphere with Mars Global Surveyor and Mars Advanced Radar for Subsurface and Ionosphere Sounding data. The model reproduces the solar zenith angle variability of the electron density and the altitude of the peak, although it underestimates the electron density at the main peak by about 20%. The electron density at the secondary peak is strongly underestimated by the model, probably due to a very crude representation of the X-ray solar flux. This is one of the aspects that needs a revision in future versions of the model. Key Points 3D simulations of the Martian ionosphere during a full Martian year Results in agreement with MGS and MARSIS observations Nightside ionosphere due to photochemistry is simulated ©2013. American Geophysical Union. All Rights Reserved. Source

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