Galaxies in X-ray Groups I: Robust Membership Assignment and the Impact of Group Environments on Quenching

Understanding the mechanisms that lead dense environments to host galaxies with redder colors, more spheroidal morphologies, and lower star formation rates than field populations remains an important problem. As most candidate processes ultimately depend on host halo mass, accurate characterizations of the local environment, ideally tied to halo mass estimates and spanning a range in halo mass and redshift are needed. In this work, we present and test a rigorous, probabalistic method for assigning galaxies to groups based on precise photometric redshifts and X-ray selected groups drawn from the COSMOS field. The groups have masses in the range 10^13 < M_200c/M_sun < 10^14 and span redshifts 0<z<1. We characterize our selection algorithm via tests on spectroscopic subsamples, including new data obtained at the VLT, and by applying our method to detailed mock catalogs. We find that our group member galaxy sample has a purity of 84% and completeness of 92% within 0.5 R200c. We measure the impact of uncertainties in redshifts and group centering on the quality of the member selection with simulations based on current data as well as future imaging and spectroscopic surveys. As a first application of our new group member catalog which will be made publicly available, we show that member galaxies exhibit a higher quenched fraction compared to the field at fixed stellar mass out to z~1, indicating a significant relationship between star formation and environment at group scales. We also address the suggestion that dusty star forming galaxies in such groups may impact the high-l power spectrum of the cosmic microwave background and find that such a population cannot explain the low power seen in recent SZ measurements.Comment: ApJ accepted. Catalogs will be posted at IRSA upon publication, currently available upon reques

WNT activation by lithium abrogates TP53 mutation associated radiation resistance in medulloblastoma

TP53 mutations confer subgroup specific poor survival for children with medulloblastoma. We hypothesized that WNT activation which is associated with improved survival for such children abrogates TP53 related radioresistance and can be used to sensitize TP53 mutant tumors for radiation. We examined the subgroup-specific role of TP53 mutations in a cohort of 314 patients treated with radiation. TP53 wild-type or mutant human medulloblastoma cell-lines and normal neural stem cells were used to test radioresistance of TP53 mutations and the radiosensitizing effect of WNT activation on tumors and the developing brain. Children with WNT/TP53 mutant medulloblastoma had higher 5-year survival than those with SHH/TP53 mutant tumours (100% and 36.6% +/- 8.7%, respectively (p < 0.001)). Introduction of TP53 mutation into medulloblastoma cells induced radioresistance (survival fractions at 2Gy (SF2) of 89% +/- 2% vs. 57.4% +/- 1.8% (p < 0.01)). In contrast, beta-catenin mutation sensitized TP53 mutant cells to radiation (p < 0.05). Lithium, an activator of the WNT pathway, sensitized TP53 mutant medulloblastoma to radiation (SF2 of 43.5% +/- 1.5% in lithium treated cells vs. 56.6 +/- 3% (p < 0.01)) accompanied by increased number of.H2AX foci. Normal neural stem cells were protected from lithium induced radiation damage (SF2 of 33% +/- 8% for lithium treated cells vs. 27% +/- 3% for untreated controls (p = 0.05). Poor survival of patients with TP53 mutant medulloblastoma may be related to radiation resistance. Since constitutive activation of the WNT pathway by lithium sensitizes TP53 mutant medulloblastoma cells and protect normal neural stem cells from radiation, this oral drug may represent an attractive novel therapy for high-risk medulloblastomas.B.R.A.I.N Child Canada; Cancer Research UK; Brain Tumour Charity; Hungarian Brain Research Program [KTIA_13_NAP-A-V/3]; Janos Bolyai Scholarship of the Hungarian Academy of Sciences [TAMOP-4.2.2. A-11/1/KONV-2012-0025]; German Cancer Aid/Dr. Mildred Scheel Foundation for Cancer Research; Cure Childhood Cancer Foundation; St. Baldrick's Foundation; Southeastern Brain Tumor Foundation; Action Medical Research; [CZ.1.05/2.1.00/03.0101]; [CZ.1.07/2.3.00/20.0183

Etude du gene du facteur de croissance des fibroblastes FGF acide et de son expression dans la retine

SIGLEINIST T 76003 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Interconnexion de reseaux informatiques et Reseau Numerique a Integration de Services: modelisation et verification d'architectures de communication

SIGLEINIST T 74527 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

What holds the Arctic together?

The Arctic region is undergoing dramatic transformation. Rapid change due to climate warming is currently affecting the Arctic more than any other region in the world: the permafrost is melting, glaciers are receding, the sea ice is shrinking. With the melting of ice, the circumpolar region is subject to increasing forces of globalization, and navigation through the Northwest and the Northeast passages is rapidly emerging as a practical and commercial proposition. Moreover, the Arctic may be home to 30 per cent of the planet's undiscovered natural gas reserves and 13 per cent of its undiscovered oil. "What Holds the Arctic Together?" The emphasis here is on convergence, rather than divergence, the Arctic's centrality not its eccentricity. The contributions gathered together in this book all address essential questions posed by geophysicists, political scientists, jurists, geographers and historians. How can science calculate and assess the scale of change in this geographic space, in particular concerning the melting of ice? To what extent are the Native populations listened to and act as active participants in decision-making concerning the Arctic? In the context of post-Cold War international and regional cooperation, what is the present state of Arctic governance? How are the Arctic States themselves cooperating in facing the challenges that lie ahead? Are existing juridical arrangements adequate? What role in the Arctic can be played by actors such as the European Union? To what extent are other powerful countries, such as the Asian giants, taking a direct interest in the development of the Arctic

What holds the Arctic together?

The Arctic region is undergoing dramatic transformation. Rapid change due to climate warming is currently affecting the Arctic more than any other region in the world: the permafrost is melting, glaciers are receding, the sea ice is shrinking. With the melting of ice, the circumpolar region is subject to increasing forces of globalization, and navigation through the Northwest and the Northeast passages is rapidly emerging as a practical and commercial proposition. Moreover, the Arctic may be home to 30 per cent of the planet's undiscovered natural gas reserves and 13 per cent of its undiscovered oil. "What Holds the Arctic Together?" The emphasis here is on convergence, rather than divergence, the Arctic's centrality not its eccentricity. The contributions gathered together in this book all address essential questions posed by geophysicists, political scientists, jurists, geographers and historians. How can science calculate and assess the scale of change in this geographic space, in particular concerning the melting of ice? To what extent are the Native populations listened to and act as active participants in decision-making concerning the Arctic? In the context of post-Cold War international and regional cooperation, what is the present state of Arctic governance? How are the Arctic States themselves cooperating in facing the challenges that lie ahead? Are existing juridical arrangements adequate? What role in the Arctic can be played by actors such as the European Union? To what extent are other powerful countries, such as the Asian giants, taking a direct interest in the development of the Arctic

New Caledonia surface lagoon chlorophyll modeling as coastal reef area health indicator

The major part of the New Caledonia (NC) lagoon was classified as UNESCO Natural Site of Humanity Patrimony. Indeed, 22 175 km(2) of tropical coral lagoon area exhibit high biodiversity. The NC lagoon is semi enclosed and connected to the Coral Sea through a barrier reef segmented by narrow passes. The environment is oligotrophic, due to important flush during trade winds events, and bathymetry is highly variable. In order to predict eutrophication events, we used an extension of a 3D coupled physical-biogeochemical model recently developed on NC south western lagoon. The model is based on the Nitrogen and Carbon cycles, relating the variable stoechiometry of the elements in each biological compartment. The ecological model was developed to include an explicit description of the microbial loop. The resulting coupled model, forced by tide, wind, light, temperature and freshwater inputs, was used to calculate phytoplankton biomass, bacterial production, dissolved organic matter concentrations and nutrient recycling. Here we present results issued from the 3D coupled model ECO3M_LAGOON (biogeochemical, LOPB-IRD) and MARS3D (regional physical model, IFREMER-IRD) describing spatial and temporal interactions between water motion and biology, on larger domain including reef barrier and water exchanges through ocean-lagoon interface. To validate physical processes in the lagoon we used in situ data collected during field cruise (ValHyBio 2008, La Nina episode). Surface chlorophyll concentrations are compared with water color data from ValHyBio cruise and satellite date (MODIS/MERIS) corrected from bathymetry effects

Implementing long-term follow-up after pediatric cancer: ethical tensions and survivors' perspective

International audienceHow the cancer episode is perceived has an impact on how the follow-up is approached. People for whom cancer is an episode of the past may be less concerned with follow-up than those for whom cancer is experienced as a chronic condition. However, this perception does not always correspond to the medically assessed state of health: the perception of cancer episode depends on the pathology/the perceived health status/the late effects of treatments/the existing medical follow-up, evolves in the same person according to the occurrence of symptoms related to lateeffects/knowledge about the risk of lateeffect/intensification or termination of followup, etc., fluctuates according to time of life and constraints or expectations associated with them. II. Different Expectations at Different Times of Life: Needs and expectations regarding LTFU vary significantly according to age, periods of life, and related constraints, or to the acceptance of the medical history that sometimes evolves

Implementing long-term follow-up after pediatric cancer: ethical tensions and survivors' perspective

International audienceHow the cancer episode is perceived has an impact on how the follow-up is approached. People for whom cancer is an episode of the past may be less concerned with follow-up than those for whom cancer is experienced as a chronic condition. However, this perception does not always correspond to the medically assessed state of health: the perception of cancer episode depends on the pathology/the perceived health status/the late effects of treatments/the existing medical follow-up, evolves in the same person according to the occurrence of symptoms related to lateeffects/knowledge about the risk of lateeffect/intensification or termination of followup, etc., fluctuates according to time of life and constraints or expectations associated with them. II. Different Expectations at Different Times of Life: Needs and expectations regarding LTFU vary significantly according to age, periods of life, and related constraints, or to the acceptance of the medical history that sometimes evolves