Extrapolation of Airborne Polarimetric and Interferometric SAR Data for Validation of Bio-Geo-Retrieval Algorithms for Future Spaceborne SAR Missions

Spaceborne SAR system concepts and mission design is often based on algorithms developed and the experience gathered from airborne SAR experiments and associated dedicated campaigns. However, airborne SAR systems have better performance parameters than their future space-borne counterparts as their design is not impacted by mass, power, and storage constraints. This paper describes a methodology to extrapolate spaceborne quality SAR image products from long wavelength airborne polarimetric SAR data which were acquired especially for the development and validation of bio/geo-retrieval algorithms in forested regions. For this purpose not only system (sensor) related parameters are altered, but also those relating to the propagation path (ionosphere) and to temporal decorrelation

Soleil Synchrotron illuminates our knowledge on gastric digestion

Soleil Synchrotron illuminates our knowledge on gastric digestion. STLOpenday

Causes of breakage and disruption in a homogeniser

Many authors have written in the past regarding the exact causes of breakage and disruption in a high pressure homogeniser, but there has been little agreement. This paper investigates some of the most likely causes of the rupture of the walls of unicellular organisms and offers suggestions obtained from various papers and work carried out

L-band ice-sheet brightness temperatures at Dome C, Antarctica: spectral emission modelling, temporal stability and impact of the ionosphere

The temporal thermal stability, size, structure and spatial uniformity of Antarctic Plateau regions such as Dome C make them ideal candidates for external calibration and validation, or radiometric performance monitoring of planned space-borne L-band radiometers such as the Soil Moisture and Ocean Salinity (SMOS) radiometer. As experimental observations do not exist at this frequency, a combination of historical Ka-, X- and C-band data are used together with electromagnetic and ionospheric models to extrapolate to this longer wavelength. Dome C is demonstrated to exhibit negligible seasonal variability (<0.1 K) and may prove to be a suitable candidate, provided the effects of atmospheric and ionospheric perturbations can be mitigated

Effect of the differences in protein structure on digestibility

Food is a complex combination of chemically diverse structures, influenced by composition andprocessing. The nutritional quality of food cannot be solely based on individual contents in nutrientsas food structure will strongly modulate the bioaccessibility of nutrients upon digestion. In previousstudies, the most common approach for measuring the extent of proteolysis and nutrient uptake wasto compare the initial macroscopic features of ingested food to final concentrations in thebloodstream. However, there is limited literature to the support underlying mechanisms of thedigestion of food in the stomach and enzyme diffusion in solid food substrates. In the present work,the influence of casein protein gel microstructure on enzymatic digestion was investigated for thefuture development of personalised foods. Casein gels with an identical composition, but differing bythe coagulation mode, were characterized and submitted to simulated gastric digestion. The changesin gel structure over time were studied using confocal microscopy and small angle x-ray scattering(SAXS). The molecular interactions that occur as a gel network is formed, and subsequently brokendown under digestive conditions will be discussed

Combination of Time Series of L-, C- and X-Band SAR Images for Land Cover and Crop Classification

The availability of new Earth observation satellites operating radar sensors at different frequencies enables the combination of multiple dimensions of the data (time, frequency, polarimetry and interferometry) in many applications. Image classification is expected to benefit from the diversity of observation. This work illustrates classification experiments carried out with series of images acquired by ALOS-2 PALSAR (L-band), Sentinel-1 (C-band) and TanDEM-X (X-band) in two application domains: land cover classification and crop-type mapping. Their usage, both separately and in combination, serves to identify the complementarity of information. In this work we propose a new colour representation of the pair-wise class separability in the case of using three frequency bands, which help identify which bands (or combinations of them) provide the best performance. Results in terms of accuracy scores (overall and class-specific) show that the use of the three frequency bands always outperforms the individual bands and their pairs. In addition, for both land classification and crop-type mapping the accuracy of using coherence time series is lower than the one obtained with the intensity time series, but there is complementarity in terms of sensitivity when both coherence and intensity time series are used together. The classes which are most benefited at each particular case of study have been identified. Finally, a partial trade-off has been found between the use of multiple frequency bands and the length of the available time series.This work was supported in part by the European Space Agency under Contract 4000133590/20/NL/AS/hh, and in part by the Spanish Ministry of Science and Innovation (State Agency of Research, AEI) and the European Funds for Regional Development under Project PID2020-117303GB-C22

Écrire la maladie au XVIIe siècle

Deux sondages ont été effectués dans l’ensemble de la production lyonnaise : l’un au début (1601-1607) et l’autre à la fin du siècle (1693-1699). Plus de la moitié des ouvrages ainsi réunis, toutes catégories confondues, s’intéressent à la maladie, la santé ou à la thérapeutique. Cette préoccupation se maintient au cours du siècle et s’appuie sur une réalité plus culturelle que pathologique : des maladies bibliques telles que la lèpre, la cécité ou la stérilité y occupent une place importante. Parallèlement à cette influence religieuse, les théories de Galien sur les humeurs prévalent dans la plupart des ouvrages. Du point de vue médical comme du point de vue chrétien, la maladie apparaît comme une anormalité, conséquence de la culpabilité des hommes. Les soins corporels comme l’assistance spirituelle tendent donc à retrouver un état de pureté originel et naturel précédent la faute. Cependant, à propos du corps lui-même, une divergence se fait jour entre ces deux regards : s’agit-il de mépriser les nécessités de la chair au profit de celles de l’âme ou, au contraire, d’admirer et de soigner la machine corporelle, création de Dieu ?Two periods of the printed production of Lyon have been studied : from 1601 to 1607 and from 1693 to 1699. In all the books gathered, it appears that more than a half of the authors (whether clergymen, historians, poets or doctors) have an interest in Illness, Health or related matters. This interest prevails all throughout the 17th century and relies on a reality which is more cultural than pathological : biblical illnesses such as leprosy, blindness or sterility assume a particular importance. But both religious and medical influences are present and Galen’s humours theory is prevalent in most of the books. Moreover, from the medical and the religious point of view alike, illness is regarded like an abnormal state, like a consequence of men’s guilt. Thus therapeutics as well as spiritual care appeal to come back to an pure paradisiacal original health. Nevertheless a divergence between medical and religious points of view appears concerning human body: should it be kept in contempt or, at the contrary, should it be admired and healed as a creation of God

On the use of rigorous microwave interaction models to support remote sensing of natural surfaces

A study has been undertaken which objective is to contribute to the investigation of the validity of microwave surface scattering models used in remote sensing applications, particularly when applied to realistic representations of natural surfaces. These investigations are based on recent implementations of rigorous methods (MoM and FDTD) and cover a wide range of configurations of observation (mono- and bi-static). Both land (bare soils) and sea surfaces are being investigated

Characterization of egg white gel microstructure and its relationship with pepsin diffusivity

Understanding the diffusion of digestive enzymes, particularly pepsin, in different food structures, is a key factorto better control protein digestion and absorption. This study aimed to investigate how protein-based foodmicrostructure impacts pepsin diffusion. Two egg white gels (EWGs) of identical protein concentration (10%)but different structures were used as food models. The two different gel structures were prepared by heatingliquid egg white at pH5 and pH9, respectively. Results showed that egg white proteins formed a compact andmicrostructurally homogeneous gel at pH9 (mean particle size of 0.32 ± 0.02 μm, with a mean interparticledistance of 0.76 ± 0.07 μm), which leads to a lower FITC-pepsin diffusion coefficient(Deff=44.2 ± 6.1 μm2 s−1), compared to the pH5-EWG (Deff=52.5 ± 5.3 μm2 s−1). The microstructure ofthe pH5-EWG was characterised by a spatially heterogeneous loose protein matrix made of larger aggregateparticles (mean particle size of 0.76 ± 0.07 μm, with a mean interparticle distance of 1.79 ± 0.57 μm). Inaddition to the effects of the EWG microstructure, the environmental pH also affects the FITC-pepsin diffusion,likely because of the impact on electrostatic interactions between pepsin and the egg white proteins

Numerical investigation of the partial oxidation in a two-stage downdraft gasifyer

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