Spectral Properties and Local Density of States of Disordered Quantum Hall Systems with Rashba Spin-Orbit Coupling

We theoretically investigate the spectral properties and the spatial dependence of the local density of states (LDoS) in disordered two-dimensional electron gases (2DEG) in the quantum Hall regime, taking into account the combined presence of electrostatic disorder, random Rashba spin-orbit in- teraction, and finite Zeeman coupling. To this purpose, we extend a coherent-state Green's function formalism previously proposed for spinless 2DEG in the presence of smooth arbitrary disorder, that here incorporates the nontrivial coupling between the orbital and spin degrees of freedom into the electronic drift states. The formalism allows us to obtain analytical and controlled nonperturbative expressions of the energy spectrum in arbitrary locally flat disorder potentials with both random electric fields and Rashba coupling. As an illustration of this theory, we derive analytical microscopic expressions for the LDoS in different temperature regimes which can be used as a starting point to interpret scanning tunneling spectroscopy data at high magnetic fields. In this context, we study the spatial dependence and linewidth of the LDoS peaks and explain an experimentally-noticed correlation between the spatial dispersion of the spin-orbit splitting and the local extrema of the potential landscape.Comment: 18 pages, 5 figures; typos corrected and Sec. IV A rewritten; published versio

Precipitation of niobium carbonitrides in ferrite: chemical composition measurements and thermodynamic modelling

High-resolution transmission electron microscopy and electron-energy loss spectroscopy have been used to characterize the structure and chemical composition of niobium carbonitrides in the ferrite of a Fe–Nb–C–N model alloy at different precipitation stages. Experiments seem to indicate the coexistence of two types of precipitates: pure niobium nitrides and mixed substoichiometric niobium carbonitrides. In order to understand the chemical composition of these precipitates, a thermodynamic formalism has been developed to evaluate the nucleation and growth rates (classical nucleation theory) and the chemical composition of nuclei and existing precipitates. A model based on the numerical solution of thermodynamic and kinetic equations is used to compute the evolution of the precipitate size distribution at a given temperature. The predicted compositions are in very good agreement with experimental results

Huygens attitude reconstruction based on flight engineering parameters

Huygens is ESA’s main contribution to the joint NASA/ESA/ASI Cassini/Huygens mission to Saturn and its largest moon Titan. The Probe, delivered to the interface altitude of 1270 km above the surface by NASA/JPL Cassini orbiter, entered the dense atmosphere of Titan on 14 January 2005 and landed on the surface after a descent under parachute of slightly less than 2.5 hours. Huygens continued to function after landing for more than 3 hours. Data was transmitted and successfully recovered by Cassini continuously during the parachute descent and for 72 minutes on the surface. Although the Huygens attitude reconstruction based on the flight engineering parameters was not foreseen during the development phase (no gyros were included), a rough descent under parachute and indications of an anomaly in the probe spin direction make the engineering dataset valuable in the frame of the ADRS (Huygens Attitude Determination and Reconstruction Subgroup) as a complement to the scientific measurements. In addition, several scientific teams have a strong interest in understanding the orientation of the probe for interpreting their data, as DISR (Descent Imager and Spectral Radiometer) and HASI-PWA (Huygens Atmospheric Structure Instrument-Permeability, Wave and Altimetry). In this paper we describe the engineering parameters used for the Probe attitude reconstruction (Clausen et al., 2002), namely the radio link AGC (Automatic Gain Control), RASU and CASU (Radial and Central Accelerometer Sensor Units) and RAU (Radar Altimeter Unit). We explain the methodology applied to indirectly infer the attitude information from the measurements of these sensors. We also discuss and present the reconstructed information related to attitude: spin rate and azimuthal position (during the atmospheric descent), and landing orientation. Tip and tilt implications are still being worked at the time of writing. Preliminary data on their behavior is presented

A functional–structural plant model that simulates whole- canopy gas exchange of grapevine plants (Vitis vinifera L.) under different training systems

Background and Aims: Scaling from single-leaf to whole-canopy photosynthesis faces several complexities related to variations in light interception and leaf properties. To evaluate the impact of canopy strucuture on gas exchange, we developed a functional–structural plant model to upscale leaf processes to the whole canopy based on leaf N content. The model integrates different models that calculate intercepted radiation, leaf traits and gas exchange for each leaf in the canopy. Our main objectives were (1) to introduce the gas exchange model developed at the plant level by integrating the leaf-level responses related to canopy structure, (2) to test the model against an independent canopy gas exchange dataset recorded on different plant architectures, and (3) to quantify the impact of intra-canopy N distribution on crop photosynthesis. Methods: The model combined a 3D reconstruction of grapevine (Vitis vinifera) canopy architecture, a light interception model, and a coupled photosynthesis and stomatal conductance model that considers light-driven variations in N distribution. A portable chamber device was constructed to measure whole-plant gas exchange to validate the model outputs with data collected on different training systems. Finally, a sensitivity analysis was performed to evaluate the impact on C assimilation of different N content distributions within the canopy. Key Results: By considering a non-uniform leaf N distribution within the canopy, our model accurately reproduced the daily pattern of gas exchange of different canopy architectures. The gain in photosynthesis permitted by the non-uniform compared with a theoretical uniform N distribution was about 18 %, thereby contributing to the maximization of C assimilation. By contrast, considering a maximal N content for all leaves in the canopy overestimated net CO2 exchange by 28 % when compared with the non-uniform distribution. Conclusions: The model reproduced the gas exchange of plants under different training systems with a low error (10 %). It appears to be a reliable tool to evaluate the impact of a grapevine training system on water use efficiency at the plant level.EEA MendozaFil: Prieto, Jorge Alejandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; Argentina.Fil: Louarn, Gaëtan. Institut National de la Recherche Agronomique; FranciaFil: Perez Peña, Jorge Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; ArgentinaFil: Ojeda, Hernan. Institut National de la Recherche Agronomique. Unité expérimentale de Pech Rouge; FranciaFil: Simonneau, Thierry. Institut National de la Recherche Agronomique. LEPSE Montpellier; FranciaFil: Lebon, Eric. Institut National de la Recherche Agronomique. Unité Mixte de Recherche; Franci

Modified Medical Research Council scale vs Baseline Dyspnea Index to evaluate dyspnea in chronic obstructive pulmonary disease

International audienceBackground: Assessment of dyspnea in COPD patients relies in clinical practice on the modified Medical Research Council (mMRC) scale, whereas the Baseline Dyspnea Index (BDI) is mainly used in clinical trials. Little is known on the correspondence between the two methods. Methods: Cross-sectional analysis was carried out on data from the French COPD cohort Initiatives BPCO. Dyspnea was assessed by the mMRC scale and the BDI. Spirometry, plethysmography, Hospital Anxiety-Depression Scale, St George's Respiratory Questionnaire, exacerbation rates, and physician-diagnosed comorbidities were obtained. Correlations between mMRC and BDI scores were assessed using Spearman's correlation coefficient. An ordinal response model was used to examine the contribution of clinical data and lung function parameters to mMRC and BDI scores. Results: Data are given as median (interquartile ranges, [IQR]). Two-hundred thirty-nine COPD subjects were analyzed (men 78%, age 65.0 years [57.0; 73.0], forced expiratory volume in 1 second [FEV1] 48% predicted [34; 67]). The mMRC grade and BDI score were, respectively, 1 [1-3] and 6 [4-8]. Both BDI and mMRC scores were significantly correlated at the group level (rho = -0.67; P < 0.0001), but analysis of individual data revealed a large scatter of BDI scores for any given mMRC grade. In multivariate analysis, both mMRC grade and BDI score were independently associated with lower FEV1% pred, higher exacerbation rate, obesity, depression, heart failure, and hyperinflation, as assessed by the inspiratory capacity/total lung capacity ratio. The mMRC dyspnea grade was also associated with the thromboembolic history and low body mass index. Conclusion: Dyspnea is a complex symptom with multiple determinants in COPD patients. Although related to similar factors (including hyperinflation, depression, and heart failure), BDI and mMRC scores likely explore differently the dyspnea intensity in COPD patients and are clearly not interchangeable

DESIRE Simulation tool to demonstrate data products for security applications

International audienceThe Simulation Tool to demonstrate Data Products for Security Applications (DESIRE) is a simulation tool aimed at demonstrating the added value of including a thermal infrared (TIR) imager within different space-borne architecture options comprising different capabilities i.e. SAR and optical. The simulator has been developed considering as end users system designers that need to assess the added value of infrared data when they are combined with other data. The DESIRE Tool development has been based on mission scenarios that address the priority areas identified in the GMES services for security e.g. Border security, Maritime Surveillance and Support to EU External Action. Particular relevant scenarios taken into account for the simulator user requirements analysis have been Oil Spill Detection, Maritime Ship Surveillance, Industrial Site Monitoring and Urban Heat Islands.The simulator is composed of an external interface capable of ingesting different input products at different processing levels (from L0 to L2, depending of the data type), a processing chain for each data type to bring the products up to L3, a co-registration module, different data combination and data fusion techniques (in order to generate merged maps or maps with information extracted from different products), and a set of modules to customize and validate the data-fusion products depending on the scenario under investigation.DESIRE has been implemented as a flexible, configurable and modular simulation tool, to be used for existing and firmly planned in-orbit capability and to combine these with real or synthetic TIR data products. DESIRE is based on the simulation framework OpenSF.The modular design of DESIRE allows the future extension of the simulator functionality with additional processing modules in order to deal with a wider range of scenarios and in-orbit architectures

Promoting a Strategic Approach to EU Sport Diplomacy

Sports policy is somewhat of ‘a new kid on the block’ for the EU. It only acquired a competence in sport following the adoption of Lisbon Treaty in 2007, in force since 2009. This is not to say the EU lacks experience in sporting matters. For many years, the EU institutions have grappled with the issue of how to reconcile the specificity of sport with the demands of EU law. This debate is ongoing, but not the subject of our enquiry. Our focus is to assist the EU in considering the merits of adopting a sport diplomacy strategy, first mooted by a High-Level Group on Sport Diplomacy in 2016. Four members of that group form part of the research team for this study. EU action since that report indicates enthusiasm for sport diplomacy. However, to act effectively in this relatively new field of EU activity, the EU institutions and the Member States require an evidence-base. The aim of our project was to undertake primary research and stage a series of Multiplier Sport Events (MSE) to provide such evidence on the efficacy of sport as a diplomatic tool. During our six MSEs, we invited a wide range of actors to share their thoughts and experiences on the practice of sport diplomacy. These events reinforced our view of the value of sport in helping the EU achieve its external relations ambitions. In this study, we claim that now is the time for the EU to act more strategically in this field and adopt an EU Sport Diplomacy Strategy

Four dimensional CT excretory Urography as an Accurate Technique for Diagnosis of Canine Ureteral Ectopia

Computed tomographic (CT) excretory urography is commonly used to investigate canine ureteral ectopia (UE). Modern technology allows time-resolved CT imaging (four-dimensional CT excretory urography [4D-CTEU]) over a distance exceeding the detector collimation. Objectives of this prospective, observational, diagnostic accuracy study were to evaluate the diagnostic accuracy of CT excretory urography (CTEU) and 4D-CTEU for UE in dogs with lower urinary tract signs, assess the influence of pelvis positioning, and to determine the significance of the ureterovesical junction (UVJ) angle for UE diagnosis. Thirty-six dogs, with a total of 42 normotopic ureters, 27 intramural ectopic ureters, and three extramural ectopic ureters, underwent CTEU and 4D-CTEU with randomized pelvis positioning. Randomized CTEU and 4D-CTEU studies were scored by two observers for ureteral papilla location and murality on a grading scheme. Interobserver agreement, sensitivity, and specificity for ureter topia status and diagnosis were calculated. Computed tomographic excretory urography showed moderate interobserver agreement for the left ureter and perfect for the right ureter, whereas 4D-CTEU showed bilateral nearly perfect agreement between both observers. When comparing CTEU versus confirmed diagnosis, there was a sensitivity and specificity of 73% and 90.2%, respectively, whereas 4D-CTEU showed a sensitivity and specificity of 97% and 94.6%, respectively. An obtuse UVJ angle is significantly more commonly observed in ectopic intramural than normotopic ureters and is significantly associated with increased diagnostic confidence of UE. The use of a wedge to angle the pelvis did not increase the diagnostic confidence in determining ureteral opening position. Four-dimensional CT excretory urography is an accurate and reliable diagnostic technique to investigate UE as cause of urinary incontinence in dogs that is slightly superior to CTEU