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Whole-Exome Sequencing Identifies LRIT3 Mutations as a Cause of Autosomal-Recessive Complete Congenital Stationary Night Blindness
No full textInternational audienc
Li-Carboxylate Anode Structure-Property Relationships from Molecular Modeling
No full textInternational audienceThe full realization of a renewable energy strategy hinges upon electrical energy storage (EES). EES devices play a key role in storing energy from renewable sources (which are inherently intermittent), to efficient transmission (e.g., grid load-leveling), and finally into the electrification of transportation. Organic materials represent a promising class of electrode active materials for Li-ion and post-Li-ion batteries. Organics consist of low-cost, lightweight, widely available materials, and their properties can be rationally tuned using the well-established principles of organic chemistry. Within the class of organic EES materials, carboxylates distinguish themselves for Li-ion anode materials based on their observed thermal stability, rate capability, and high cyclability. Further, many of the carboxylates studied to date can be synthesized from renewable or waste feedstocks. This report begins with a preliminary molecular density-functional theory (DFT) study, in which the calculated molecular properties of a set of 12 known Li-ion electrode materials based on carboxylate and carbonyl redox couples are compared to literature data. Based on the agreement between theoretical and experimental data, an expanded study was undertaken to identify promising materials and establish design principles for anodes based on Li-carboxylate salts. Predictive computational studies represent an important step forward for the identification of organic anode materials
Combinatorial activity of Six1-2-4 genes in cephalic neural crest cells controls craniofacial and brain development.
No full textoai:HAL:hal-00920398v1International audience: The combinatorial expression of Hox genes is an evolutionarily ancient program underlying body axis patterning in all Bilateria. In the head, the neural crest (NC)--a vertebrate innovation that contributes to evolutionarily novel skeletal and neural features--develops as a structure free of Hox-gene expression. The activation of Hoxa2 in the Hox-free facial NC (FNC) leads to severe craniofacial and brain defects. Here, we show that this condition unveils the requirement of three Six genes, Six1, Six2, and Six4, for brain development and morphogenesis of the maxillo-mandibular and nasofrontal skeleton. Inactivation of each of these Six genes in FNC generates diverse brain defects, ranging from plexus agenesis to mild or severe holoprosencephaly, and entails facial hypoplasia or truncation of the craniofacial skeleton. The triple silencing of these genes reveals their complementary role in face and brain morphogenesis. Furthermore, we show that the perturbation of the intrinsic genetic FNC program, by either Hoxa2 expression or Six gene inactivation, affects Bmp signaling through the downregulation of Bmp antagonists in the FNC cells. When upregulated in the FNC, Bmp antagonists suppress the adverse skeletal and cerebral effects of Hoxa2 expression. These results demonstrate that the combinatorial expression of Six1, Six2, and Six4 is required for the molecular programs governing craniofacial and cerebral development. These genes are crucial for the signaling system of FNC origin, which regulates normal growth and patterning of the cephalic neuroepithelium. Our results strongly suggest that several congenital craniofacial and cerebral malformations could be attributed to Six genes' misregulation
Seven new loci associated with age-related macular degeneration
No full textInternational audienceAge-related macular degeneration (AMD) is a common cause of blindness in older individuals. To accelerate the understanding of AMD biology and help design new therapies, we executed a collaborative genome-wide association study, including >17,100 advanced AMD cases and >60,000 controls of European and Asian ancestry. We identified 19 loci associated at P < 5 × 10−8. These loci show enrichment for genes involved in the regulation of complement activity, lipid metabolism, extracellular matrix remodeling and angiogenesis. Our results include seven loci with associations reaching P < 5 × 10−8 for the first time, near the genes COL8A1-FILIP1L, IER3-DDR1, SLC16A8, TGFBR1, RAD51B, ADAMTS9 and B3GALTL. A genetic risk score combining SNP genotypes from all loci showed similar ability to distinguish cases and controls in all samples examined. Our findings provide new directions for biological, genetic and therapeutic studies of AMD
How the Saint Santin incoherent scatter system paved the way for a French involvement in EISCAT
No full textInternational audienceThis paper relates the development of a French incoherent scatter system which started its operations in 1965. This development took place several years after the initial implementation of such systems in the United States, in Peru and in the United Kingdom. The French system, owing to its bistatic configuration and the use of continuous waves, differed from the previous ones. These characteristics yielded signals of excellent spectral quality, unravelling the possibility of inferring physical parameters (Doppler shift, average ion mass) out of reach, at that time, of other systems. The possibility of making ion drift vector measurements led to extend the system into a quadristatic configuration. The multiple capabilities offered by the incoherent scatter technique, notably as concerns the thermodynamical properties of the ionosphere and of the thermosphere, led further the French community to a project of embarking an incoherent scatter radar on board a ship. Taking account of a project of a Scandinavian auroral zone radar and of the considerable interest of the study of auroral zone electrodynamics, the French community abandoned the idea of the ship and expressed an interest in joining the Scandinavian project in conjunction with Germany and the United Kingdom
