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Nuclear energy and bio energy carbon capture and storage, keys for obtaining 1.5°C mean surface temperature limit
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Viva Europa, a Land of Excellence in Research and Innovation for Health and Wellbeing
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New characterizations for the eigenvalues of the prolate spheroidal wave equation
No full textInternational audienceIn this paper, we give new characterizations for the eigenvalues of the prolate wave equation as limits of the zeros of some families of polynomials: the coefficients of the formal power series appearing in the solutions near 0, 1 or ∞ (in the variables x, x − 1 or 1/x respectively). The result, which seems to be true for all values of the parameter τ , according to our numerical experiments, is here proved for small values of the parameter τ
Pressure Dependence of the Metal-Insulator and Superconducting Phase Transitions in (TMTSF)2 ReO4
No full textInternational audienceregime about 2.5 kbar i n width i n which both superc o n d u c t i v i t y and e f f e c t s of anion o r d e r i n g a r e observed. I n t h i s regime ( i ) a superconducting t r a n s i t i o n i s Seen n e a r 1.3 K even though p j u s t above t h e t r a n s i t i o n can be up t o 10-100 times g r e a t e r than p(300 K ) , and ( i i ) t h e r e is an e x t r ' i o r d i n a r i l y l a r g e h y s t e r e s i s i n p below</div
350 ans de science
No full text1666-2016 : la séance solennelle commémorant les 350 ans de l'Académie des sciences s’est tenue le 28 juin 2016 sous la coupole de l’Institut de France. Huit académiciens, comme autant de sections de l’Académie, ont retracé l’histoire de leur discipline en mettant en lumière les étapes importantes qui ont été franchies et en rendant hommage aux principaux scientifiques, français ou étrangers, qui ont concouru à l’évolution, voire à la révolution, de leur discipline. Ce numéro spécial de La Lettre de l’Académie des sciences présente les actes de cette grande journée dédiée à l’histoire des sciences
Water and Food in the Twenty-First Century
No full textInternational audienceIn 2000, the World population was 6.2 billion people; it reached 7 billion in 2012 and is expected to reach 9.5 billion (±0.4) in 2050 and 11 billion (±1.5) in 2100, according to the 2012 UN projections (Gerland et al. in Science 346:234–237, 2014). The trend after 2100 is still one of the global demographic growths, but after 2060, Africa is the only continent where the population would still increase. The amount of water consumed annually to produce the food necessary to meet the needs of the populations varies greatly between countries, from about 600 to 2500 m3/year per capita (Zimmer in L’empreinte eau. Les faces cachées d’une ressource vitale. Charles Léopold Meyer, Paris, 2013), depending on their wealth, their food habits, and the percentage of food waste they generate (on average, 30 % of the food produced is wasted). In 2000, the total food production was on the order of 3300 million tons (in cereal equivalents). In 2014, it is estimated that about 0.8 billion inhabitants of the planet suffer from hunger (FAO in World agriculture: towards 2030–2050. FAO, Rome, 2014. http://www.fao.org/docrep/004/Y3557E/y3557e00.HTM) and do not get the nutrition they need to be in good health or, in the case of children, to grow properly (both physically and intellectually). This food deficit was on the order of 40 million tons of cereal equivalents in 2014. The number of inhabitants with a food deficit was about 0.85 billion before the 2008 crisis and was decreasing annually, but it increased abruptly after 2008 up to 1 billion inhabitants and is slowly decreasing now. Assuming a World average water consumption for food of 1300 m3/year per capita in 2000, 1400 m3/year in 2050, and 1500 m3/year in 2100, a volume of water of around 8200 km3/year was needed in 2000, 13,000 km3/year will be needed in 2050, and 16,500 km3/year in 2100 (Marsily in L’eau, un trésor en partage. Dunod, Paris, 2009). Can bioenergy be added to food production? Will that much water be available on Earth, and where will it come from? Is climate change going to modify the answers to these questions? Can severe droughts occur? Can there be conflicts related to a food deficit? Some preliminary answers and scenarios for food production will be given in this paper from a hydrologist’s viewpoint
Martinique Crinkled Retinal Pigment Epitheliopathy
No full textInternational audiencePURPOSE:To reappraise the autosomal dominant Martinique crinkled retinal pigment epitheliopathy (MCRPE) in light of the knowledge of its associated mutated gene mitogen-activated protein kinase-activated protein kinase 3 (MAPKAPK3), an actor in the p38 mitogen-activated protein kinase pathway.DESIGN:Clinical and molecular study.PARTICIPANTS:A total of 45 patients from 3 generations belonging to a family originating from Martinique with an autosomal dominant MCRPE were examined.METHODS:Best-corrected visual acuity, fundus photographs, and spectral-domain optical coherence tomography (SD OCT) of all clinically affected patients and carriers for the causal mutation were reviewed at the initial visit and 4 years later for 10 of them. Histologic retinal lesions of Mapkapk3(-/-) mice were compared with those of the human disease.MAIN OUTCOME MEASURES:The MCRPE natural history in view of MAPKAPK3 function and Mapkapk3(-/-) mouse retinal lesions.RESULTS:Eighteen patients had the c.518T>C mutation. One heterozygous woman aged 20 years was asymptomatic with normal fundus and SD OCT (stage 0). All c.518T>C heterozygous patients older than 30 years of age had the characteristic dried-out soil fundus pattern (stages 1 and 2). Complications (stage 3) were observed in 7 cases, including polypoidal choroidal vasculopathy (PCV) and macular fibrosis or atrophy. One patient was homozygous and had a form with severe Bruch's membrane (BM) thickening and macular exudation with a dried-out soil pattern in the peripheral retina. The oldest heterozygous patient, who was legally blind, had peripheral nummular pigmentary changes (stage 4). After 4 years, visual acuity was unchanged in 6 of 10 patients. The dried-out soil elementary lesions radically enlarged in patients with a preferential macular extension and confluence. These findings are in line with the progressive thickening of BM noted with age in the mouse model. During follow-up, there was no occurrence of PCV.CONCLUSIONS:MCRPE is an autosomal dominant, fully penetrant retinal dystrophy with a preclinical stage, an onset after the age of 30 years, and a preserved visual acuity until occurrence of macular complications. The natural history of MCRPE is in relation to the role of MAPKAPK3 in BM modeling, vascular endothelial growth factor activity, retinal pigment epithelial responses to aging, and oxidative stress
Clinical characteristics and risk factors of extensive macular atrophy with pseudodrusen The EMAP case-control national clinical trial
No full textPurpose: To assess the association of clinical and biological factors with extensive macular atrophy with pseudodrusen (EMAP) characterized by bilateral macular atrophy occurring in patients aged 50 to 60 years and a rapid progression to legal blindness within 5 to 10 years. Design: A national matched case-control study. Participants: Participants were recruited in 10 French Departments of Ophthalmology and their associated clinical investigation centers. All 115 patients with EMAP had symptoms before the age of 55 years due to bilateral extensive macular atrophy with a larger vertical axis and diffuse pseudodrusen. Three controls without age-related macular degeneration (AMD) or retinal disease at fundus examination were matched for each patient with EMAP by gender, age, and geographic area (in total 415). Methods: Subjects and controls underwent an eye examination including color, red-free autofluorescent fundus photographs and spectral-domain optical coherence tomography with macular analysis. The interviews collected demographic, lifestyle, family and personal medical history, medications, and biological data. Associations of risk factors were estimated using conditional logistic regression. Main Outcome Measures: Extensive macular atrophy with pseudodrusen status (cases vs. controls). Results: Extensive macular atrophy with pseudodrusen most frequently affected women (70 women, 45 men). After multivariate adjustment, family history of glaucoma or AMD was strongly associated with EMAP (odds ratio [OR], 2.3, P = 0.008 and OR, 1.5, P = 0.01, respectively). No association was found with cardiac diseases or their risk factors. Mild and moderate kidney disease and higher neutrophil rate were associated with a reduced risk of EMAP (OR, 0.58, P = 0.04; OR, 0.34, P = 0.01; and OR, 0.59, P = 0.003, respectively). On the contrary, eosinophilia (OR, 1.6; P = 0.0002), lymphocytosis (OR, 1.84; P = 0.0002), increased erythrocyte sedimentation rate (OR, 6.5; P = 0.0005), decreased CH50 (P = 0.001), and high plasma C3 level (P = 0.023) were significantly associated with a higher risk of EMAP. Conclusions: This study documents an association between EMAP and family history of AMD and glaucoma, a clear female predominance, and a systemic inflammatory profile. The reduced CH50 and increased C3 plasma values could reflect a more severe complement pathway dysfunction than in AMD, leading to early pseudodrusen and rapid development of geographic atrophy. There is no association of EMAP with AMD cardiac diseases or cardiac risks, including cigarette smoking
Identification of a Novel Homozygous Nonsense Mutation Confirms the Implication of GNAT1 in Rod-Cone Dystrophy
No full textInternational audienceGNAT1, encoding the transducin subunit Gα, is an important element of the phototransduc-tion cascade. Mutations in this gene have been associated with autosomal dominant and autosomal recessive congenital stationary night blindness. Recently, a homozygous trun-cating GNAT1 mutation was identified in a patient with late-onset rod-cone dystrophy. After exclusion of mutations in genes underlying progressive inherited retinal disorders, by targeted next generation sequencing, a 32 year-old male sporadic case with severe rod-cone dystrophy and his unaffected parents were investigated by whole exome sequencing. This led to the identification of a homozygous nonsense variant, c.963C>A p.(Cys321*) in GNAT1, which was confirmed by Sanger sequencing. The mother was heterozygous for this variant whereas the variant was absent in the father. c.963C>A p.(Cys321*) is predicted to produce a shorter protein that lacks critical sites for the phototransduction cascade. Our work confirms that the phenotype and the mode of inheritance associated with GNAT1 variants can vary from autosomal dominant, autosomal recessive congenital stationary night blindness to autosomal recessive rod-cone dystrophy