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IASI-derived monthly mean infrared (10 μm) dust aerosol optical depth (AOD) and altitude are evaluated against ground based AERONET measurements of the 500nm coarse mode AOD and CALIOP measurements of the altitude at 38 AERONET sites within the tropical belt (30° N-30° S). The period covered extends from July 2007 to December 2012. The evaluation goes through the analysis of Taylor diagrams and box and whiskers plots, separating situations over sea and over land. Concerning AOD, the overall correlation for the sites over sea comes to 0.88 for 713 items (IASI and AERONET monthly mean bins). The overall normalized standard deviation is of 0.96. Over land, essentially desert, correlation is of 0.74 for 582 items and the normalized standard deviation is of 0.87. This slight but significant degradation over land most probably results from the greater complexity of the surface (heterogeneity, elevation) and, to a lesser extent, to the episodic presence of dust within the boundary layer (particularly for sites close to active sources) to which IASI, as any thermal infrared sounder, is poorly sensitive contrary to AERONET. Concerning altitude over sea, correlation is of 0.78 for 925 items and the normalized standard deviation is of 1.03. Results over land, essentially over deserts, are not satisfactory for a majority of sites. To the reasons listed above for the AOD must be added the smaller IASI signal induced by the altitude compared to the signal induced by the AOD. Site by site, disparities appear that we estimate being principally due to either the insufficient number of AERONET observations throughout the period considered, to the complexity of the situation mixing several aerosol types (case of the Persian Gulf, for example), to surface heterogeneities (elevation, emissivity, etc.), or to the use of a single aerosol model ("MITR"). Results using another aerosol model with different refractive indices are presented and discussed. We conclude that the present results demonstrate the usefulness of IASI data as an additional constraint to a better knowledge of the impact of aerosols on the climate system. [ABSTRACT FROM AUTHOR]

Infrared Atmospheric Sounder Interferometer (IASI) observations covering the period from July 2007 to December 2011 are interpreted in terms of monthly mean, 1°x1°, 10 µm dust Aerosol Optical Depth (AOD), mean altitude and coarse mode effective radius. The geographical study area includes the northern tropical Atlantic and the north-west Arabian Sea, both characterized by strong, regular dust events. The method developed relies on the construction of Look-Up-Tables computed for a large selection of atmospheric situations and observing conditions. At regional scale, a good agreement is found between IASI-retrieved 10 µm AOD and total visible optical depth at 550nm from either the Moderate resolution Imaging Spectroradiometer (MODIS/Aqua or Terra), or the Multi-angle Imaging SpectroRadiometer (MISR), or the Polarization and Anisotropy of Reflectances for Atmospheric Science coupled with Observations from a Lidar (PARASOL). Taking into account the ratio existing between infrared and visible AODs, the diversity between the different 550nm AODs is similar to the difference between these and the IASI AODs. The infrared AOD to visible AOD ratio, partly reflecting the varying distribution of the dust layer between the dust coarse mode particles seen by IASI, and the fine mode seen by the other instruments, is found to vary with the region observed with values close to already published values. Comparisons between the climatologies of the 10 µm IASI AOD and of the PARASOL non-spherical coarse mode AOD at 865 nm, both expected to be representative of the dust coarse mode, lead to conclusions differing according to the region considered. These differences are discussed in the light of the MODIS Angström exponent (865-550 nm). At local scale, around six Aerosol Robotic Network (AERONET) sites, close or far from the dust sources, a similar satisfactory agreement is found between IASI and the visible AODs and the differences between these products are shown and analysed. IASI-retrieved dust layer mean altitudes also compare well with the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP/CALIPSO) aerosol mean layer altitude, both in terms of climatology and of zonal evolution throughout the Atlantic. Comparisons between the IASI-retrieved dust coarse mode effective radius and retrievals from AERONET at the six sites brings into evidence an almost systematic bias of about +0.35 (IASIAERONET). Removing this bias leads to a satisfactory agreement between the climatologies of these two products. Overall, these results illustrate the dust westward transport characterized by a fast decrease of the dust optical depth, a somewhat slower decrease of the altitude, and an effective radius remaining almost constant during summer throughout the northern tropical Atlantic. They also demonstrate the capability of high resolution infrared sounders to contribute improving our understanding of processes related to the aerosols (transport, sources, cycles, effect of aerosols on the terrestrial radiation, etc.). [ABSTRACT FROM AUTHOR]

Monthly mean infrared (10 μm) dust layer aerosol optical depth (AOD) and mean altitude are simultaneously retrieved over the tropics (30° S-30° N) from six years of Atmospheric Infrared Sounder (AIRS) observations covering the period January 2003 to December 2008. The method developed relies on the construction of Look-up-Tables computed for a large selection of atmospheric situations and follows two main steps: first, determination of the observed atmospheric thermodynamic situation and, second, determination of the dust properties. A very good agreement is found between AIRS-retrieved AODs and visible optical depths from the Moderate resolution Imaging Spectroradiometer (MODIS/Aqua) during the main (summer) dust season, in particular for three regions of the tropical North Atlantic and one region of the north-western Indian Ocean. Outside this season, differences are mostly due to the sensitivity of MODIS to aerosol species other than dust and to the more specific sensitivity of AIRS to the dust coarse mode. AIRS-retrieved dust layer mean altitudes are compared to the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP/CALIPSO) aerosol mean layer altitude for the period June 2006 to December 2008. Results for a region of the north tropical Atlantic downwind of the Sahara show a good agreement between the two products (σ≈370 m). Differences observed in the peak-to-trough seasonal amplitude, smaller from AIRS, are principally attributed to the large difference in spatial sampling of the two instruments. They also come from the intrinsic limit in sensitivity of the passive infrared sounders at low altitudes. These results however demonstrate the capability of high resolution infrared sounders to measure not only dust aerosol AOD but also the mean dust layer altitude. [ABSTRACT FROM AUTHOR]

Major limitations of our present knowledge of the global distribution of CO2 in the atmosphere are the uncertainty in atmospheric transport mixing and the sparseness of in situ concentration measurements. Limb viewing spaceborne sounders, observing the atmosphere along tangential optical paths, offer a vertical resolution of a few kilometers for profiles, which is much better than currently flying or planned nadir sounding instruments can achieve. In this paper, we analyse the feasibility of obtaining CO2 vertical profiles in the 5-25 km altitude range from the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS, launched in August 2003), high spectral resolution solar occultation measurements. Two main difficulties must be overcome: (i) the accurate determination of the instrument pointing parameters (tangent heights) and pressure/temperature profiles independently from an a priori CO2 profile, and (ii) the potential impact of uncertainties in the temperature knowledge on the retrieved CO2 profile. The first difficulty has been solved using the N2 collisioninduced continuum absorption near 4μm to determine tangent heights, pressure and temperature from the ACE-FTS spectra. The second difficulty has been solved by a careful selection of CO2 spectral micro-windows. Retrievals using synthetic spectra made under realistic simulation conditions show a vertical resolution close to 2.5 km and accuracy of the order of 2 ppm after averaging over 25 profiles. These results open the way to promising studies of transport mechanisms and carbon fluxes from the ACE-FTS measurements. First CO2 vertical profiles retrieved from real ACE-FTS occultations shown in this paper confirm the robustness of the method and applicability to real measurements. [ABSTRACT FROM AUTHOR]

Objective: The aim of the study was to determine the trend of first blood prostate-specific antigen (PSA) test prescription in France between 2011 and 2017, based on the assumption that prostate cancer (PCa) screening is expected to decline over the years., Method: Using a representative sample of the French population from the French Health Insurance database, we identified 50-52-year-old men without PCa and without any blood PSA test in the five years before 2011, 2014 and 2017 (January 1-December 31 of each year). For each of these three years, the primary outcome was the first reimbursement of a blood PSA test. We used a logistic regression model with first blood PSA test as the outcome and year as the main explanatory variable. As secondary objectives, we also identified the prescriber's specialty, the urological consultation frequency, and the number of prostate biopsies in the year after the first blood PSA test reimbursement (only for 2011 and 2014)., Results: In 2011, 2014 and 2017, 5 275, 5 792 and 5 887 50-52-year-old men, respectively, were included. The percentage of patients with a first blood PSA test prescription decreased linearly from 2011 to 2017: 15.7% in 2011, 13.2% in 2014, and 12.4% in 2017 ( p  < .001). Blood PSA testing was mainly prescribed by general practitioners (>95%). The median interval between PSA tests was 13 months in 2011 and 14 months in 2014. Fewer than 10% of men had ≥1 consultation with an urologist during the year after the first blood PSA test. After the first blood PSA test, eight prostate biopsies were performed in 2011 and two in 2014., Conclusion: Our results suggest that in France, PCa screening is a primary care issue. Although PCa screening remains controversial and confusion exists about the best practice, our study showed a linear decrease of blood PSA test prescriptions for 50-52-year-old men between 2011 and 2017, although the reason for screening was unknown. As clinical information was not available, additional evidence is needed to determine the real impact of this decrease on the cancer-specific and overall mortality.

Deposition of mineral dust into ocean fertilizes ecosystems and influences biogeochemical cycles and climate. In-situ observations of dust deposition are scarce, and model simulations depend on the highly parameterized representations of dust processes with few constraints. By taking advantage of satellites' routine sampling on global and decadal scales, we estimate African dust deposition flux and loss frequency (LF, a ratio of deposition flux to mass loading) along the trans-Atlantic transit using the three-dimensional distributions of aerosol retrieved by spaceborne lidar (CALIOP) and radiometers (MODIS, MISR, and IASI). On the basis of a ten-year (2007-2016) and basin scale average, the amount of dust deposition into the tropical Atlantic Ocean is estimated at 136 - 222 Tg yr -1 . The 65-83% of satellite-based estimates agree with the in-situ climatology within a factor of 2. The magnitudes of dust deposition are highest in boreal summer and lowest in fall, whereas the interannual variability as measured by the normalized standard deviation with mean is largest in spring (28-41%) and smallest (7-15%) in summer. The dust deposition displays high spatial heterogeneity, revealing that the meridional shifts of major dust deposition belts are modulated by the seasonal migration of the intertropical convergence zone (ITCZ). On the basis of the annual and basin mean, the dust LF derived from the satellite observations ranges from 0.078 to 0.100 d -1 , which is lower than model simulations by up to factors of 2 to 5. The most efficient loss of dust occurs in winter, consistent with the higher possibility of low-altitude transported dust in southern trajectories being intercepted by rainfall associated with the ITCZ. The satellite-based estimates of dust deposition can be used to fill the geographical gaps and extend time span of in-situ measurements, study the dust-ocean interactions, and evaluate model simulations of dust processes.

Loss of hair cells in the mammalian cochlea leads to permanent sensori-neural hearing loss. Hair cells degenerate and their places are taken by phalangeal scars formed by non-sensory supporting cells. Current data indicate that early postnatal post-mitotic supporting cells can proliferate and differentiate into hair cell-like cells in culture. In this study, we used GFAP and nestin promoter-GFP transgenic mice in combination with other stem cell markers to characterize supporting cell subtypes in the postnatal day-3 (P3) and adult organs of Corti with potential stem/progenitor cell phenotype. In P3 organ of Corti, we show GFAP-GFP signal in all the supporting cell subtypes while the nestin-GFP was restricted to the supporting cells in the inner hair cell area. At this stage, GFAP and selected stem/progenitor markers displayed overlapping expression pattern in the supporting cell population. In the adult, GFAP expression is down-regulated from the supporting cells in the outer hair cell area and nestin expression is down-regulated in the supporting cells of the inner hair cell area. Sox2 and Jagged1 expression is maintained in the mature supporting cells, while Abcg2 was down-regulated in these cells. In contrast, GFAP and Abcg2 expression was up-regulated in the inner sulcus limbal cells outside the mature organ of Corti's area. Using quantitative reverse transcription-PCR, we found a decrease in transcripts for Jagged1 and Sox2 in adult cochleae. Our findings suggest that the loss of regenerative capacity of the adult organ of Corti is related to down-regulation of stem/progenitor key-markers from the mature supporting cells., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Background: Kernel moisture at harvest is an important trait since a low value is required to prevent unexpected early germination and ensure seed preservation. It is also well known that early germination occurs in viviparous mutants, which are impaired in abscisic acid (ABA) biosynthesis. To provide some insight into the genetic determinism of kernel desiccation in maize, quantitative trait loci (QTLs) were detected for traits related to kernel moisture and ABA content in both embryo and endosperm during kernel desiccation. In parallel, the expression and mapping of genes involved in kernel desiccation and ABA biosynthesis, were examined to detect candidate genes., Results: The use of an intermated recombinant inbred line population allowed for precise QTL mapping. For 29 traits examined in an unreplicated time course trial of days after pollination, a total of 78 QTLs were detected, 43 being related to kernel desiccation, 15 to kernel weight and 20 to ABA content. Multi QTL models explained 35 to 50% of the phenotypic variation for traits related to water status, indicating a large genetic control amenable to breeding. Ten of the 20 loci controlling ABA content colocated with previously detected QTLs controlling water status and ABA content in water stressed leaves. Mapping of candidate genes associated with kernel desiccation and ABA biosynthesis revealed several colocations between genes with putative functions and QTLs. Parallel investigation via RT-PCR experiments showed that the expression patterns of the ABA-responsive Rab17 and Rab28 genes as well as the late embryogenesis abundant Emb5 and aquaporin genes were related to desiccation rate and parental allele effect. Database searches led to the identification and mapping of two zeaxanthin epoxidase (ZEP) and five novel 9-cis-epoxycarotenoid dioxygenase (NCED) related genes, both gene families being involved in ABA biosynthesis. The expression of these genes appeared independent in the embryo and endosperm and not correlated with ABA content in either tissue., Conclusions: A high resolution QTL map for kernel desiccation and ABA content in embryo and endosperm showed several precise colocations between desiccation and ABA traits. Five new members of the maize NCED gene family and another maize ZEP gene were identified and mapped. Among all the identified candidates, aquaporins and members of the Responsive to ABA gene family appeared better candidates than NCEDs and ZEPs.

Indoor mould growth can affect health, especially in early childhood. As part of a birth cohort follow-up, the purpose of this study was firstly to examine spectrum and levels of airborne fungi in 190 Paris newborns' dwellings, and secondly to identify predictors of these levels. Sequential duplicate air samples were collected twice a year in the newborn's bedroom and outside the building. A single-stage multi-holed impactor (Air Ideal) was used with chloramphenicol/MEA agar. Housing characteristics were assessed using a questionnaire administered by a trained interviewer. Cladosporium and Penicillium were isolated in, respectively, 77% and 93% of homes in the cold season, and in 95% and 83% of homes in the hot season. Aspergillus and Alternaria were recovered from indoor air in, respectively, 60% and less than 20% of homes. Geometric means (geometric standard deviation) of indoor total airborne fungal concentrations at two different visits were, respectively, 232.4 (3.2) and 186.7 (2.7)cfu/m(3). In the GEE multivariate analysis, outdoor fungal concentrations were the best predictors for variability of indoor total fungal and Cladosporium concentrations (respectively, R(2)=32% and 31%). Levels of total airborne fungal and Cladosporium concentrations were significantly higher during the hot season (respectively, p=0.003 and p<0.001) and were positively correlated with the duration of bedroom aeration (respectively, p=0.004 and p<0.001). Signs of dampness were associated with higher total airborne fungi (p=0.031) and Aspergillus levels (p=0.055). This study provides for the first time indoor airborne fungal spectrum and concentrations in Paris. Outdoor levels and season largely contributed to the variability of indoor total airborne fungal concentrations, which also depended on aeration and signs of dampness.