[1] The column-average dry air mole fractions of atmospheric carbon dioxide and methane (X CO 2 and X CH 4 ) are inferred from observations of backscattered sunlight conducted by the Greenhouse gases Observing SATellite (GOSAT). Comparing the first year of GOSAT retrievals over land with colocated ground-based observations of the Total Carbon Column Observing Network (TCCON), we find an average difference (bias) of −0.05% and −0.30% for X CO 2 and X CH 4 with a station-to-station variability (standard deviation of the bias) of 0.37% and 0.26% among the 6 considered TCCON sites. The root-mean square deviation of the bias-corrected satellite retrievals from colocated TCCON observations amounts to 2.8 ppm for X CO 2 and 0.015 ppm for X CH 4 . Without any data averaging, the GOSAT records reproduce general source/sink patterns such as the seasonal cycle of X CO 2 suggesting the use of the satellite retrievals for constraining surface fluxes. Citation: Butz, A., et al. (2011), Toward accurate CO 2 and CH 4 observations from GOSAT, Geophys.

Recent demonstrations of optically pumped lasers based on GeSn alloys put forward the prospect of efficient laser sources monolithically integrated on a Si photonic platform. For instance, GeSn layers with 12.5% of Sn were reported to lase at 2.5 µm wavelength up to 130 K. In this work, we report a longer emitted wavelength and a significant improvement in lasing temperature. The improvements resulted from the use of higher Sn content GeSn layers of optimized crystalline quality, grown on graded Sn content buffers using Reduced Pressure CVD. The fabricated GeSn micro-disks with 13% and 16% of Sn showed lasing operation at 2.6 µm and 3.1 µm wavelengths, respectively. For the longest wavelength (i.e 3.1 µm), lasing was demonstrated up to 180 K, with a threshold of 377 kW/cm² at 25 K.

We have grown various thickness Ge layers on nominal and 6 • off Si(0 0 1) substrates using a low-temperature/high-temperature strategy followed by thermal cycling. A combination of 'mounds' and a perpendicular cross-hatch were obtained on nominal surfaces. On 6 • off surfaces, three sets of lines were obtained on top of the 'mounds': one along the 1 1 0 direction perpendicular to the misorientation direction and the other two at ∼4.5 • on each side of the 1 1 0 direction parallel to the misorientation direction. The surface root mean square roughness was less than 1 nm for 2.5 μm thick nominal and 6 • off Ge layers. Those slightly tensily strained Ge layers (R ∼ 104%) were characterized by 5 × 10 7 cm −2 (as-grown layers) −10 7 cm −2 (annealed layers) threading dislocation densities, independently of the substrate orientation. We have then described the 550 • C/650 • C process used to passivate nominal Ge(0 0 1) surfaces with Si prior to gate stack deposition. An ∼5 Å thick SiGe interfacial layer is self-limitedly grown at 550 • C and then thickened at 650 • C (5 Å min −1 ) thanks to SiH 2 Cl 2 at 20 Torr. Such a Ge surface passivation yields state-of-the-art p-type metal oxide semiconductor field effect transistors provided that 15 Å Si layer thickness is not exceeded. For higher thickness, elastic strain relaxation (through the formation of numerous 2D islands) occurs, followed by plastic relaxation (for a 35 Å thick Si layer).

The incidence of a sella turcica bridge in combination with a PITX2 mutation would suspect that sella turcica anomalies are typical symptoms of the syndrome. Sella turcica anomalies in association with craniofacial and dental aberrations, such as maxillary retrognathia, skeletal Class III relationship and hypoplasia of teeth, might be important indicators for ARS caused by PITX2 mutation.

GeSn alloys are the subject of intense research activities as these group IV semiconductors present direct bandgap behaviors for high Sn contents. Today, the control of strain becomes an important challenge to improve GeSn devices. Strain micro-measurements are usually performed by Raman spectroscopy. However, different relationships linking the Raman spectral shifts to the built-in strain can be found in the literature. They were deduced from studies on low Sn content GeSn layers (i.e. xSn<8%) or on GeSiSn layers. In this work, we have calibrated the GeSn Raman relationship for really high Sn content GeSn binaries (6

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Two approaches have been compared for the low temperature epitaxy of thick, partially relaxed GeSn layers on top of Ge strain relaxed buffers. The benefit of using step-graded instead of constant composition layers when targeting really high Sn contents (16%, here) was conclusively demonstrated. Digermane (Ge 2 H 6 ) and tin-tetrachloride (SnCl 4 ) were used as Ge and Sn precursors, respectively. The growth pressure (100 Torr) and the F(Ge 2 H 6 )/F(SnCl 4 ) mass-flow ratio being constant, it was through a temperature lowering that the Sn concentration in the graded structure was increased. X-ray diffraction, atomic force microscopy and transmission electron microscopy were used to gain access to the Sn concentration, the strain state, the surface morphology and thicknesses of the heterostructures. Using a step-graded approach allowed us to gradually relax the strain in the GeSn layers. It helped us obtain high crystalline quality and avoid Sn segregation/precipitation for high Sn contents.

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