Modelling soil moisture at SMOS scale by use of a SVAT model over the Valencia Anchor Station

16 páginas, 9 figuras, 5 tablas.The main goal of the SMOS (Soil Moisture and Ocean Salinity) mission is to deliver global fields of surface soil moisture and sea surface salinity using L-band (1.4 GHz) radiometry. Within the context of the Science preparation for SMOS, the Valencia Anchor Station (VAS) experimental site, in Spain, was chosen to be one of the main test sites in Europe for Calibration/Validation (Cal/Val) activities. In this framework, the paper presents an approach consisting in accurately simulating a whole SMOS pixel by representing the spatial and temporal heterogeneity of the soil moisture fields over the wide VAS surface (50x50 km(2)). Ground and meteorological measurements over the area are used as the input of a Soil-Vegetation-Atmosphere-Transfer (SVAT) model, SURFEX (Externalized Surface) - module ISBA (Interactions between Soil-Biosphere-Atmosphere) to simulate the spatial and temporal distribution of surface soil moisture. The calibration as well as the validation of the ISBA model are performed using in situ soil moisture measurements. It is shown that a good consistency is reached when point comparisons between simulated and in situ soil moisture measurements are made. Actually, an important challenge in remote sensing approaches concerns product validation. In order to obtain an representative soil moisture mapping over the Valencia Anchor Station (50x50 km(2) area), a spatialization method is applied. For verification, a comparison between the simulated spatialized soil moisture and remote sensing data from the Advanced Microwave Scanning Radiometer on Earth observing System (AMSR-E) and from the European Remote Sensing Satellites (ERS-SCAT) is performed. Despite the fact that AMSR-E surface soil moisture product is not reproducing accurately the absolute values, it provides trustworthy information on surface soil moisture temporal variability. However, during the vegetation growing season the signal is perturbed. By using the polarization ratio a better agreement is obtained. ERS-SCAT soil moisture products are also used to be compared with the simulated spatialized soil moisture. However, the lack of soil moisture data from the ERS-SCAT sensor over the area (45 observations for one year) prevented capturing the soil moisture variability.The authors wish to thank the European Space Agency (ESA), the Centre National d’Etudes Spatiales (CNES), the Centre National de la Recherche Scientifique – Institut National des Sciences de l’Univers (CNRS- INSU SIC) and the French National Programme TOSCA (Terre, Oc´eans, Surfaces Continentales et Atmosph´ere) for supporting this work. We also wish to thank the NASA National Snow and Ice Data Center (NSIDC) for providing AMSR-E data as well as the Institute for Photogrammetry and Remote Sensing, Vienna University of Technology, Vienna, Austria for providing the ERS-SCAT data. We thank also the Centre National de Recherches Météorologiques and Jean Christophe Calvet (CNRM) - Météo-France for the SURFEX model. The authors wish to thank also the Spanish Agency for Meteorology (AEMet) and to the Jucar River Basin Authority (CHJ) for the meteorological data. Edited by: N. Verhoest The publication of this article is financed by CNRS-INSU.Peer reviewe

MERTIS: Optics manufacturing and verification

The MERTIS reflective infrared optics can be beneficial implemented as diamond turned aluminium mirrors coated with a thin gold layer. The cutting processes allow the manufacturing of both, the optical surface and mechanical interfaces, in tight tolerances. This is one of the major advantages of metal optics and was consequently used for the MERTIS sensor head optics. This paper describes the entire process chain of the MERTIS spectrometer optics including the manufacturing methods for the mirrors and for the spherical grating, the coating with sputtered gold for infrared reflectivity as well as the alignment and the verification of the spectrometer optics

Ultra-precisely manufactured mirror assemblies with well-defined reference structures

Aspherical surfaces for imaging or spectroscopy are a centerpiece of high-performance optics. Due to the high alignment sensitivity of aspheric surfaces, reference elements and interfaces with a tight geometrical relation to the mirror are as important as the high quality of the optical surface itself. The developed manufacturing method, which accounts for the shape and also for the position of the mirror surfaces, allows controlling and precisely correcting not only the form, but also the alignment of reference marks, interfaces or even other mirrors in the sub-assembly using diamond turning. For Korsch or TMA telescopes it is also possible to diamond turn whole sub-assemblies containing two or more mirrors with a relative position error as low as the machine precision. Reference elements allow the correction of the shape and position of mirrors as well as the position of interfaces for system integration. The presented method opens up a novel manufacturing strategy to enhance the relative positioning accuracy of optic assemblies by one order of magnitude

Lens array manufacturing using a driven diamond tool on an ultra precision lathe

The integration of a high spced spindic onto an Ultra Precision (UP) lathe gives the ability to manufacture aspheric lens arrays with high form accuracy, bw roughness and a precise pitch control in diamond machinable metal alloys, crystals and plastic substrates. The machine kinematics of the precision lathe with two linear and one rotary axis has a major impact 011 the NC-code generation and the tool setting process. The present paper illustrates the general set-up and the tool path generation in detail. The achieved form accuracy and surface roughness of the lens arrays are shown and discussed

Anamorphotic telescope for earth observation in the mid-infrared range

In the framework of the “Earth Explorer” program, the European Space Agency had foreseen the PREMIER mission intended to monitor the three-dimensional distribution of trace gasses in the atmosphere

Athermal metal optics made of nickel plated AlSi40

Metal optics is an inherent part of space instrumentation for years. Diamond turned aluminum (Al6061) mirrors are widely used for application in the mid- and near-infrared (mid-IR and NIR, respectively) spectral range. Aluminum mirrors plated with electroless nickel (NiP) expand the field of application towards multispectral operating instruments down to the ultraviolet wavelengths. Due to the significant mismatch in the coefficient of thermal expansion (CTE) between aluminum and NiP, however, this advantage occurs at the cost of bimetallic bending. Challenging requirements can be met by using bare beryllium or aluminum beryllium composites (AlBeMet) as a CTE tailored substrate material and amorphous NiP as polishable layer. For health reasons, the use of beryllium causes complications in the process chain. Thus, the beryllium approach is subjected to specific applications only. Metal optics has proven to be advantageous in respect of using conventional CNC and ultra-precision fabrication methods to realize complex and light-weighted instrument structures. Moreover, the mirror designs can be effectively optimized for a deterministic system assembly and optimization. Limitations in terms of dimensional stability over temperature and time are mainly given by the inherent material properties (figures of merit) of the substrate material in interaction with the polishing layer. To find an optimal compromise, a thermal matched aluminum-silicon alloy (silicon contents ≈ 40 wt%) plated with NiP (AlSi40/NiP ) was investigated in a joined project of the Max Planck Institute for Astronomy MPIA and the Fraunhofer Institute for Applied Optics and Precision Engineering IOF. The main tasks of the project were the minimization of the bimetallic bending, the development of reliable stabilizing and aging procedures, and the establishment of a proven fabrication method. This paper describes fundamental results regarding the optimization of the athermal material combination. Furthermore, the developed production chain for high quality freeform mirrors made of AlSi40/NiP is pointed out

Allosteric inhibition of Taspase1's pathobiological activity by enforced dimerization in vivo

Taspase1 mediates cleavage of the mixed lineage leukemia (MLL) protein and leukemia-provoking MLL fusions and promotes solid malignancies. Currently, no effective and specific Taspase1 inhibitors are available, precluding its therapeutic exploitation. As the Taspase1 proenzyme is autoproteolytically cleaved and assumed to assemble into an active alpha beta beta alpha heterodimer, we attempted to interfere with its activity by targeting Taspase1's dimerization. Notably, enforced expression of inactive Taspase1 mutants, aiming to inhibit formation of active protease dimers, was not inhibitory. Immunoprecipitation, gel filtration, and in vivo protein interaction assays revealed that active Taspase1 exists predominantly as an alpha beta monomer in living cells, providing an explanation why overexpression of inactive mutants was not trans-dominant. To alternatively test the biological consequences of enforced dimerization, we engineered Taspase1 variants containing the Jun/Fos dimerization motif. In absence of the respective interaction partners, the protease fusions were fully active, while enforcing dimerization by coexpression significantly inhibited processing of several target proteins in living cells. Our study provides the first evidence that Taspase1 is already active as an alpha beta monomer, arguing against heterocomplex formation being required for its pathobiological activity. Thus, it clearly supports strategies aiming to inhibit the cancer-promoting activity of Taspase1 by the identification of chemical decoys enforcing its dimerization.-Bier, C., Knauer, S. K., Wunsch, D., Kunst, L., Scheiding, S., Kaiser, M., Ottmann, C., Kramer, O. H., Stauber, R. H. Allosteric inhibition of Taspase1's pathobiological activity by enforced dimerization in vivo. FASEB J. 26, 3421-3429 (2012). www.fasebj.or

Comparison of the long-term outcome of two therapeutic strategies for the management of abdominal abscess complicating Crohn's disease: percutaneous drainage or immediate surgical treatment

AimThe management of abdominal abscesses complicating Crohn's disease is complex and involves a difficult choice between medical, radiological and surgical procedures. The long-term outcome was compared for two strategies for the management of abdominal abscess: percutaneous drainage (PD) followed by rescue surgery in the case of failure vs direct immediate surgery (IS). We also compared the results of IS with surgery performed after PD failure. MethodsWe retrospectively identified 44 patients with Crohn's disease with an abdominal abscess from January 2000 to December 2009. Therapeutic success was defined as abscess resolution and no reappearance within 1year of follow-up. ResultsThe first therapeutic approach was PD in 22 cases and IS in the other 22 cases. IS had a higher therapeutic success rate than PD (95.5% vs 27.2% respectively; P<0.001). PD was the only independent variable related to treatment failure in the multivariate analysis after adjustment for possible confounders such as abscess size, multilocularity, presence of fistula and corticosteroid use (OR 88.26, 95% CI 7.38-1055.36; P<0.001). Surgery after failure of PD (n=16) was associated with longer total hospitalization (56.1235.89 vs 27.52 +/- 15.11days; P=0.017) and longer postoperative stay (44.0 +/- 83.7 vs 14.3 +/- 30days; P=0.179) and needed a second operation more often (5/16, 31% vs 1/22, 4.5%; P=0.065) than IS. ConclusionsPercutaneous drainage provided durable abscess resolution in only one-third of the patients compared with more than 90% of those treated with IS. In addition, surgery performed after PD failure results in a poorer outcome than IS