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The current period is characterized by an abundance of free access radar data, the use of which is encouraged and facilitated by space agencies, the latter providing free software for image processing and analysis to users. At the same time, several academic or institutional sites offer explanatory resources (courses, software tutorials) on general or targeted topics intended to facilitate the use of images in most fields of application. In this paper, we wish to address and detail a particular point ; that of the physical concept of the radar measurement, through the various software processing proposed during a sequence of georeferencing-calibration of the images. This sequence, which combines geometrical and radiometric aspects, is found for applications relating to the characterization of the various media present on the surface of the ground or to facilitate the analysis of temporal sequences. After presenting the general aspects related to the power measured at the sensor and the various factors influencing this measurement, we will focus on the user practice, by discussing the different choices of coefficients β0, σ0, γ0, offered during a calibration following a geo-referencing, as well as on the taking into account, or not, slope effects in geometric and radiometric corrections affecting the image. Particular attention is paid to the coefficient γ0 whose variations as a function of local incidence are considered very low in the case of dense forests. [ABSTRACT FROM AUTHOR]

While both FSH and LH molecules present in the gonadotropin preparations manufactured from the urines proved to be efficient, the critical role of FSH in the process of follicular growth is likely to explain why products with FSH activity only were subsequently developed. For that reason, molecules with FSH only activity were manufactured with a progressive improvement in the process of purification allowing an increase in the specific activity of the products. However, several drawbacks in the urine collection emerged when a dramatic increase in the need of products was evident further to the development of In Vitro Fertilization in the late 80s: involvement of countries where the quality control was poos regarding the sources of donors, the ways of urine storage and transportation and the risk of virus contamination. In addition, the possible advantage of the LH activity supplementation suggested by some scientists led to the production of urinary products where LH molecules were extracted and substituted with hCG in a FSH/LH ratio of 1 as done in the 60s. However, whatever the manufacture of urinary products, their low specific activity related to urinary contaminants and their poor batch to batch consistency can easily explain why they could not satisfy clinicians in their daily practice. Meanwhile, identification of FSH genes simultaneously with the emergence of DNA recombinant technologies allowed the production of recombinant FSH molecules. This was actually a major step forward in the process of gonadotropin supply: no limitation in production, an improved safety due to the traceability of the process, higher purity and bio-activity as compared to urinary products. However, the final step in the manufacture process was still dependent on the Steelman & Pohley bioassay consisting in the measurement of the rat ovarian weight. The major drawback of the bioassay was actually its imprecision. Because Follitropin alpha can be produced with a highly constant isoform profile, it can be eventually calibrated through a simple and highly precise measurement of the mass (Filled by mass process). This step was absolutely critical to improve the batch to batch consistency of the final product and, eventually, the reproducibility of the ovarian response. The technics of recombinant technology, eventually applied to gonadotropins, are clearly a new step forward at the benefit of couples. [ABSTRACT FROM AUTHOR]

In order to answer statutory requirements and to anticipate the future needs and standards, the EFS is committed, since a few years, in a process of harmonization of its metrology function. In particular, the institution has opted for the skills development by internalizing the metrological traceability of the main critical quantities (temperature, volumetric) measurements. The development of metrology so resulted in a significant increase in calibration and testing activities. Methods are homogenized and improved through accreditations. The investment strategies are based on more and more demanding specifications. The performance of the equipments is better known and mastered. Technical expertise and maturity of the national metrology function today are assets to review in more informed ways the appropriateness of the applied periodicities. Analysis of numerous information and data in the calibration and testing reports could be pooled and operated on behalf of the unique establishment. The objective of this article is to illustrate these reflections with a few examples from of a feedback of the EFS Pyrénées Méditerranée. The analysis of some methods of qualification, the exploitation of the historical metrology in order to quantify the risk of non-compliance, and to adapt the control strategy, analysis of the criticality of an instrument in a measurement process, risk analyses are tools that deserve to be more widely exploited for that discipline wins in efficiency at the national level. [ABSTRACT FROM AUTHOR]

Abstract: A recent survey among French anesthesiologists revealed that monitoring of curarization is used in approximately in 50% of cases after a unique dose of curare and in 75% of cases after repeated doses of curare. In this survey, a majority of clinicians used a quantitative monitor based on acceleromyography, i.e. that the majority of clinicians used a device from the TOF-watch® product line. Results obtained by these monitors depends on the model used, TOF-Watch®, TOF-Watch S® or TOF-Watch SX®, as well as if it is used for a single point measurement at the end of the operation or continuously throughout the operation, with or without calibration, and if a calibration is used, should we used Cal 1 or Cal 2? Technical specifications and their impact on results will be developed in this technical note. This will help clinicians to better interpret results obtained by TOF-watch® monitors in order to improve clinical decisions based on monitoring of neuromuscular transmission. [Copyright &y& Elsevier]

Abstract: Objective: Thoracic bioimpedance has been proposed for cardiac output (CO) determination and monitoring without calibration or thermodilution (ICG Monitor 862146, Philips Medical System, Philips, Suresnes, France). The accuracy and clinical applicability of this technology has not been fully evaluated in the cardiac surgery setting. We designed this prospective study to compare the accuracy of the ICG Monitor (COICG) versus pulmonary artery catheter standard bolus thermodilution (COPAC) in patients after cardiac surgery or having benefited from cardiac surgery. Study design: Prospective, monocentric. Material and methods: We studied 13 patients in the postoperative period. COICG and COPAC were determined at the arrival in the intensive care unit and every four hours. Bland-Altman and Critchley and Critchley''s analysis were used to assess the agreement between COICG and COPAC. Results: COPAC ranged from 2.6 to 11.0l/min and COICG ranged from 1.8 to 11.7l/min. There was a significant relationship between COPAC and COICG (r =0.61 ; p <0.001). Agreement between COPAC and COICG was −0.5±1.3l/min (Bland-Altman analysis). Percentage error between the two methods was 49% (Critchley and Critchley''s analysis). Conclusion: We found clinically unacceptable agreement between COICG and COPAC in this setting. Despite its non invasiveness, this device cannot be recommended for CO monitoring in the postoperative period following cardiac surgery. [Copyright &y& Elsevier]

In Amazonia, because the small catchments are ungauged, it is not possible to analyse them, for example, for hydroelectric power production. Thus, the objective of this paper is to study the transferability of a rainfall-runoff model to simulate flow duration curves for the production of hydroelectric power. The approach is based on the transfer of the impulse response of a model calibrated on two gauged catchments, allowing the evaluation approach permutation between these two catchments. We have, respectively, 7 years and 2 years and 2 months of rainfall and runoff data for these catchments. A sensitivity analysis of the transferability calibration to the sample size is carried out to determine the shortest flow period gauged on the receptor catchment, which produces results comparable to those calibrated with the maximum samples size. This analysis evaluates fieldwork on the ungauged sites of the region. En Amazonie, les petits bassins versants ne disposent pas de données de débit, ce qui empêche l’étude de ces bassins, par exemple, pour des fins de production d’énergie hydroélectrique. Ainsi, l’objectif de ce travail est d’étudier la transférabilité d’un modèle pluie-débit pour simuler les débits classés en vue d’une planification de la production hydroélectrique. L’approche est basée sur le transfert de la réponse impulsionnelle d’un modèle étalonné sur deux bassins jaugés permettant l’évaluation de la permutation de l’approche. Sur ces bassins test, on dispose respectivement de 7 ans et de 2 ans et 2 mois de données de pluie et de débit. L’analyse de sensibilité de l’étalonnage de la transférabilité détermine la taille minimale de la série de débits mesurés sur le bassin cible qui assure encore des résultats comparables à ceux étalonnés avec les échantillons de taille maximale de débits. Celle-ci évalue l’effort de mesures sur des sites non jaugés de la région. [ABSTRACT FROM AUTHOR]

This paper proposes an approach to represent the dynamic behaviour of a river through reliable transfer functions. This approach was applied to the Péribonka River, in Quebec. The paper describes the design of these functions between the Chutes-des-Passes and Chute-du-Diable power plants, including the Péribonka power plant under construction (at the time this paper was written). The FLDWAV software models the flows under various production conditions. The model was calibrated over several summers using data from the Péribonka River gauging station. The multiple flow transfer functions obtained under various flow conditions and water levels were simplified for use in production optimization. They were validated on each river section. Tests show these functions correlate well with open water flow dynamics. However, these flow transfer functions are not recommended for winter water flow simulation. Une méthode pour représenter les comportements dynamiques d’une rivière par des fonctions de transfert fiables est proposée. Elle est appliquée à la rivière Péribonka (Québec). L’article détaille la création de ces fonctions entre les centrales Chutes-des-Passes et Chute-du-Diable, incluant la centrale Péribonka en construction (lors de la rédaction de cet article). Le logiciel FLDWAV modélise les écoulements sous des conditions de production variées. Le modèle a été étalonné sur plusieurs saisons estivales grâce aux stations hydrométriques de la rivière Péribonka. Les multiples fonctions de transfert de débit (FTD) obtenues pour diverses conditions de débit et de niveau d’eau ont été simplifiées en vue de leur usage en optimisation de la production. Elles ont été validées sur chaque tronçon de la rivière. Les tests montrent qu’elles respectent bien la dynamique des écoulements en eau libre. Toutefois, l’utilisation des mêmes FTD n’est pas recommandable pour simuler l’écoulement de l’eau en période hivernale. [ABSTRACT FROM AUTHOR]

Abstract: ‘Turbidity’ information can be obtained from the backscatter intensity of an ADCP, by computing a volume backscatter index, the dynamics of which is correlated to tide and wave forcing. This backscatter index is obtained from the ADCP signal, taking into account the transmission losses and the acoustical characteristics of our ADCP, calibrated in a test tank. In order to quantify the mass concentration, an empirical calibration of the backscatter index is obtained with independent measurements with an optical turbidimeter. The results show that in the present environment (with tide and waves) a one-level calibration is sufficient to obtain in-water profiles of mass concentration from the ADCP measurements. Moreover, the duration of calibration operations can be reduced to about two days, with the essential condition of measuring a sufficient dynamics of mass concentration, met under spring water conditions with waves. [Copyright &y& Elsevier]

The objective of this work is to construct reduced-order models based on POD ("Proper Orthogonal Decomposition") that are able to accurately reproduce the spatio-temporal dynamics of separated flows. The growing interest concerning these models comes from their potential use in the resolution of large scale constrained optimization problems, in the context of flow control. The general approach consists in substituting the high-fidelity model of the Navier-Stokes equations by an approximate model, cheaper to compute and capturing the essential features of the original dynamics. POD, which is the optimal decomposition in terms of energy, allows to approximate the flow dynamics in a subspace spanned by a few number of modes. Different calibration methods are developed here in order to improve the accuracy of the reduced-order models, and thus make this approach suitable for flow control issues. Essentially, the idea of the calibration methods is to determine in the equations of the POD reduced-order models auxiliary parameters that are computed by resolving appropriate constrained minimization problems. [ABSTRACT FROM AUTHOR]

Abstract: The influence of climate on plants geography is studied through a probabilistic calibration between a botanical database, containing 12 000 plots, and a meteorological database composed of 574 climatic stations. The calibration measures the climatical optimum (position) and the indicator power (concentration) of 1874 plants for six climatic variables. The validation of these relations is based upon the comparison of the estimation of climate by plants and the values measured by climatic stations near the plots. This validation underlines that plants are accurate (accuracy=88.5%) and stable (stability=96.5%) bio-indicators of climate variables. To cite this article: E. Garbolino et al., C. R. Biologies 330 (2007). [Copyright &y& Elsevier]

Abstract: Regional and University Hospitals of Lille holds many of analysis laboratories with a great diversity of biology specialities. To date, a great biology center is building to accommodate there all these laboratories at the beginning of 2007. In this biology center, a room of metrology is foreseen where will be carried out the update of the metrological checks on the equipment concerned and the metrological traceability. The analysis laboratories of medical biology must have a perfect control of their equipment within the framework of the analytical process in order to ensure the quality of their results. This first work is a reflection on the failures of the metrology function within the laboratories from the biomedical point of view. Finally, the objective will be to provide to the laboratories of a coherent and homogeneous metrology tool to all the specialities of the biology of the CHRU of Lille to the service of their quality assurance. [Copyright &y& Elsevier]

In very long baseline interferometry, the image reconstruction procedures are very sensitive to the potential instabilities of the phase calibration operation. The analysis presented in this Note reveals that these instabilities are due to the existence of secondary minima (more or less critical) of the phase calibration objective functional. By resolving the corresponding integer ambiguity problems in an appropriate manner, these minima can be explicitly identified and compared. The stability of the self-calibration procedures can thus be easily controlled. To cite this article: A. Lannes, C. R. Physique 4 (2003). [Copyright &y& Elsevier]

The geological work undertaken in the north oriental regions of Algeria have considered the plain of Tamlouka, region of Guelma, as a meeting crossroad of the three structural domains of Sellaoua, Néritic Constantine, and Tellian. The tectonic contact between the overthrust sheets is hidden by a thick alluvium cover and has remained undetermined in spite of recent exploration attempts by a geoelectric method. In this paper, we present the results of our work on the reinterpretation of the basic geoelectric data, which were founded on the calibration principle, considering all the geological information available from outcrops and cuttings of recent drill holes. Twenty-nine geoelectric profiles and three maps are drawn in which (i) the facies and geometry of the Mio-Plio-Quaternary fill are much better identified; (ii) an underground synthesis of the relation between the tectonic units is proposed after an inventory of the subsurface formations; and (iii) the ground-water potential in the plain is much better assessed.Key words: geoelectric method, geometry, overthrust sheets, ground-water potential, Tamlouka, Algeria.Les travaux géologiques entrepris dans les régions Nord orientales de l'Algérie ont considéré la plaine de Tamlouka « région de Guelma » comme le carrefour de rencontre de trois domaines structuraux : du Sellaoua, du Néritique constantinois et du Tellien. Le contact tectonique entre les nappes qui sont masquées par une puissante couverture alluvionnaire est resté indéterminé malgré les tentatives récentes de son exploration par méthodes géoélectriques. Dans cet article, nous exposons les résultats du travail de ré-interprétation des données géoélectriques de base, fondé sur le principe d'étalonnage et prenant en compte la totalité des informations géologiques des affleurements ainsi que des débris de forages implantés récemment. Vingt-neuf profils géoélectriques et trois cartes sont dressés et avec lesquels : (i) le faciès et la géométrie du remplissage Mio-Plio-Quaternaire sont mieux identifiés; (ii) une synthèse des relations souterraines entre les unités tectoniques est avancée après une reconnaissance des formations substratums; (iii) une identification de la possibilité aquifère dans la plaine est mieux précisée.Mots clés : méthode géoélectrique, géométrie, nappe de charriage, potentiel aquifère, Tamlouka, Algérie. [ABSTRACT FROM AUTHOR]

Study aim: The risk of dysphagia after antireflux surgery seems to be increased with laparoscopy compared with open surgery. Calibration of the hiatus is usually done by the surgeon’s finger during open surgery. The aim of this study was to assess the results of laparoscopic calibration with a Fogarty balloon catheter.Patients and methods: Between 1999 and 2001, 21 patients had a laparoscopic Toupet 240° fundoplication with hiatus calibration using a 4ml-inflated 8G Fogarty balloon catheter. These patients were compared with a group of 21 patients without hiatus calibration, matched for age, sex, preoperative dysphagia and esophageal dysmotility. Judgment criteria was early and/or late postoperative dysphagia (> 3 months).Results: Median follow-up was 13 months. The rate of early dysphagia with and without calibration were 66% and 48% respectively (NS). Median duration of early dysphagia with and without calibration were 25 and 43 days respectively (p=0.05). No patient with calibration had late dysphagia. One patient (5%) without calibration had unexplained late dysphagia for 2 years. He had preoperative esophageal dysmotility without œsophagitis.Conclusion: Hiatus calibration with a Fogarty balloon catheter decreased early postoperative dysphagia duration after Toupet laparoscopic fundoplication. This easily reproductible technical point standardizes the hiatus closure and should be recommended. [Copyright &y& Elsevier]