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International audience; This paper shows that natural materials such as barks can successfully replace synthetic resins for industrial purposes. Evaluated in batch conditions, biosorption of uranium on suitably prepared Douglas fir barks took place in less than 10 min and appeared to be optimum at pH>4. The biosorption process of uranium (uranyl form UO2 2+) was characterized in the optimal physico-chemical conditions and could be mathematically modeled as a Langmuir isotherm. With a maximum uranium specific uptake qmaxvalue of 1.16 meq.g-1 (138 mgU.g-1) it was found that the sorption capability of Douglas fir barks was at least five times higher for uranium than for other heavy metals such as lead. Adsorption of uranium contained in water leached from a former uranium mine was then monitored over a one-month period in a laboratory-scale chromatography column. The fixation capacity remained fairly constant throughout the whole testing period. Water radioactivity decreased from 1500 mBq.L-1 (0.12 mgU.L-1) to

India, which produced nearly 67 Mt steel in 2010, aims to produce, in the near future, more than 100 Mt/year and to become, after China, the second largest steelmaker worldwide. To do this, India benefits from large iron ore reserves, especially of high-grade hematites, which presently constitute the largest amount of the local consumption as well of the exports. For the future, however, it will be necessary to beneficiate the large reserves of lower-grade iron ores, especially the magnetites. Furthermore, the question of the amount of the Indian iron ores available for export will have to be considered. India also has very large coal resources but, unhappily, mainly in non-coking coal, and often with high ash content: this is the main problem of the Indian iron and steel industry, to select the best routes and processes to make steel. The Indian iron and steel industry has to choose between: the conventional route based on the Blast Furnace and Oxygen Converter, which implies increasing the imports of high-grade coking coal, mainly from Australia; various routes based on local Indian coals, such as: (a) COREX or FINEX processes to produce liquid hot metal, or (b) direct reduction processes, either based on natural gas where it is available, or on local coals, presently mainly in rotary kilns (but with serious problems of energy efficiency and environmental pollution, in spite of the large present development), or based on coal gasification processes (such as MXCOL or ITmk3 processes). Finally, another special feature of the Indian iron and steel companies, specially of the largest private ones such as Tata, Essar and JSW (Jindal), is their development outside of India, which means the control of some 18 Mt steel/year, aiming to reach about 25 Mt/year in the near future!

The Arab Steel Summit, that convened in Abu Dhabi in April, gave us another opportunity to review the situation of the Arab Iron and Steel Industry, with regard to the present World economic context. We will address: The World situation of steel production, focusing on the Arab Countries; The related situation of steel consumption; The steel trade, including imports, exports and prices; The consequences for technology and economy.

The XXIV IMPC (International Mineral Processing Congress) which took place in Beijing from September 23 to 28, 2008 gave an opportunity to see the important development in Iron Ore processing worldwide, especially in China. This review paper presents: A brief history of the IMPC Congresses as well as the scope of this XXIV IMPC in Beijing; The development of the Iron Ore demand and supply of the Chinese Iron and Steel Industry and the consequences on Iron Ore imports; The impressive expansion of the Iron Ore mining and processing in China.

Objectif : Un desequilibre du metabolisme du cuivre est a l'origine de maladies genetiques graves ; la maladie de Menkes lors de deficits en cuivre et la maladie de Wilson caracterisee par une surcharge en cet oligo-element. Le diagnostic des ces pathologies implique le dosage du cuivre serique et urinaire par spectrometrie d'absorption atomique electrothermique (SAAE). Nous decrivons ici le protocole de validation de notre technique de dosage du cuivre serique par SAA. Methode : Nous avons applique un protocole recommande par la Societe Francaise des Sciences Techniques et Pharmaceutiques (SFSTP). Resultats : Ce protocole nous a permis de tester la linearite, la fidelite et l'exactitude de notre methode et de definir le domaine de linearite ainsi que les limites de detection et de quantification. Conclusion : L'etude realisee a permis de valider la methode de dosage utilisee au laboratoire.

The growing demand of steel products in a rapidly developing economy and increasing levels of imports in the Arab World progress the development of local steel production. The steel industry develops along the processes most appropriate to local resources: DR processes and EAF operation.

The recent meeting “ARAB STEEL SUMMIT 2007” organized by The Arab Iron and Steel Union at Muscat (Oman Sultanate) March 12-14, 2007 afforded the opportunity to analyze: The development of the Iron and Steel Industry in the Arab States, The main actors behind such developments, The characteristics, both technical and metallurgical of these enterprises.

We present distance measurements to 71 high redshift type Ia supernovae discovered during the first year of the 5-year Supernova Legacy Survey (SNLS). These events were detected and their multi-color light-curves measured using the MegaPrime/MegaCam instrument at the Canada-France-Hawaii Telescope (CFHT), by repeatedly imaging four one-square degree fields in four bands. Follow-up spectroscopy was performed at the VLT, Gemini and Keck telescopes to confirm the nature of the supernovae and to measure their redshift. With this data set, we have built a Hubble diagram extending to z=1, with all distance measurements involving at least two bands. Systematic uncertainties are evaluated making use of the multi-band photometry obtained at CFHT. Cosmological fits to this first year SNLS Hubble diagram give the following results : Omega_M = 0.263 +/- 0.042(stat) +/- 0.032(sys) for a flat LambdaCDM model; and w = -1.023 +/- 0.090(stat) +/- 0.054(sys) for a flat cosmology with constant equation of state w when combined with the constraint from the recent Sloan Digital Sky Survey measurement of baryon acoustic oscillations.

We present a novel technique for fitting restframe I-band light curves on a data set of 42 Type Ia supernovae (SNe Ia). Using the result of the fit, we construct a Hubble diagram with 26 SNe from the subset at 0.01< z

This paper reports on the Congress of the Arab Iron and Steel Union (AISU) that has been convened in Beirut, Lebanon, September 29 - October 1, 2004. Presentations dealt with the global theme of the development of the steel industry in the Arab Countries or with the technical aspects of steel production routes and continuous casting.

In the metallurgical industry, very few innovative processes reached the industrial stage. The purpose of this article is to identify the key principles for monitoring an industrialization process, and to assess their validity. Mastering the industrialization process is a key to hopefully succeed in developing efficiently an innovative and competitive process; according to industry characteristics and past cases of process developments, there might be a “virtuous” six-step industrialization process for metallurgy; the review of present industrialization processes within two metallurgical routes tends to confirm that point.

After presentation of the historical background, the present structure of the Arab steel industry is described and its main characteristics discussed: insufficient domestic steel production, based on hot metal, scrap and mainly prereduced iron, high imports of semi-products, important development of the use of electric arc furnaces. Indications are then given on the rapid evolution of the steel industry in Egypt, Morroco and Saudi-Arabia, and on new, modern and larger capacity installations, in particular electric arc furnaces and rolling mills.

Chez la Drosophile, le cœur est un simple tube lineaire, le tube cardiaque, forme a partir de 52 paires de cellules myoendotheliales, qui, en fin d’embryogenese, se differencient pour donner un organe fonctionnel. C’est un organe pulsatile, a activite musculaire autonome, qui assure le flot de l’hemolymphe dans un systeme de circulation ouvert. Le tube cardiaque est compose de metameres, comprenant six paires de cardioblastes dans chacun des segments. A l’interieur de chaque metamere, les cardioblastes presentent une diversite genetique importante qui s’accompagne d’une diversite fonctionnelle. Par exemple, les deux paires de deux cardioblastes les plus posterieurs dans chacun des segments A5 a A7 se differencient en ostioles, qui constituent les voies afferentes et permettent l’entree de l’hemolymphe dans la cavite cardiaque.Cette diversification segmentale est completee par une information axiale qui est a l’origine de la mise en place de l’aorte, dans la partie anterieure du tube, et du cœur, dans la partie posterieure, avec des proprietes fonctionnelles associees specifiques. L’activite pacemaker principale est localisee dans la partie la plus caudale.Cette analyse de la morphogenese du cœur a ete rendue possible grâce a l’utilisation de marqueurs genetiques et morphologiques specifiques et a une observation in vivo du fonctionnement cardiaque chez l’embryon.L’organogenese fonctionnelle du tube cardiaque est controlee par des programmes genetiques precis qui ont ete en partie identifies. Ainsi les genes Hox sont responsables de la division du tube en modules fonctionnels dans l’axe anteroposterieur. Ils activent dans leurs domaines d’expression des genes cibles effecteurs de la differenciation terminale. D’autre part, une partie de l’information necessaire a la diversification segmentale des cardioblastes est fournie par le morphogene Hedgehog, produit et secrete par l’ectoderme dorsal, dont l’activite dirige la differenciation d’ostioles uniquement dans le domaine cœur.

This paper gives an account of the symposium organized in May 2002 in the memory of Dr Wolf, who died in November 2001. Many experts in the field of continuous casting have participated to this symposium, which has been the occasion to review the progress made in the continuous casting of conventional and thin slabs and to evaluate the state of the art and perspectives of thin strip casting. At the same time, general trends for the future in the steel industry have been discussed.

In Europe, like elsewhere, the share of steel produced by electric arc furnaces from scrap increases. As the amount of internal scrap has decreased considerably, the steel plants recycle more and more collected obsolete and capital scrap. This source of iron has increased rapidly and will continue to increase. In spite of that, some plants may have to include in their EAF charge prereduced iron coming from countries where natural gas is available at low cost.

Two fusion-fission experiments have been performed and studied with the Euroball Ge array: 12 C + 238 U at 90MeV bombarding energy, and 18 O + 208 Pb at 85MeV. Among the lot of new information extracted during the last decade, the latest results discussed here are the discovery of the high-spin states of 119-126 Sn. The maximum value of angular momentum available in the νh11/2 shell, i.e. for mid-occupation and the breaking of the three neutron pairs (seniority v = 6), has been identified in several tin isotopes. It is the first time that such high-seniority states are established in spherical nuclei.

L’activite des principes actifs habituellement utilises au cours des leishmanioses a pu etre amelioree, en les incorporant a un vecteur.Nous presentons un modele in vitro permettant l’etude des interactions leishmanies-nanoparticules chargees ou non chargees. Ce travail a ete realise avec deux types de nanoparticules : des nanospheres de polyisoalkylcyanoacrylate, vecteur particulaire, biodegradable et des nanospheres de methacrylate non chargees et chargees de pentamidine.Le modele associe la lignee mono-histiocytaire U397 et des formes amastigotes de Leishmania major. La methodologie a consiste a mettre en contact, des concentrations de l’ordre de 5 a 50 µg/ml pour les polyisoalkylcyanoacrylates et de 50 a 200 µg/ml pour les polymeres de methacrylate vis-a-vis de 3.105 cellules infectees/ml ; l’efficacite des nanoparticules est evaluee 24 h plus tard en microscopie optique par mesure de l’index de l’infestation residuelle.Nous presentons ici les resultats des essais aux concentrations pour lesquelles nous obtenons une alteration ou une disparition des leishmanies dans les vacuoles d’endocytose.La validite et l’interet de ces resultats sont discutes.

Organise par l’Union Arabe du Fer et de l’Acier (UAFA) pour son 20e anniversaire, sous les auspices du Ministere algerien de l’Industrie et des Mines, ce seminaire a mis l’accent sur l’evolution de la consommation et de la production de ferrailles dans les pays en voie de developpement, en particulier les pays arabes, et sur les progres de la reduction directe dans ces pays.

Reduction is an important step in steelmaking. Two routes have practically been developed : a smelting reduction route, and a melting route.This situation can be changing :– gradually (« evolution »),– or radically (« revolution »), with the research effort.The article aims at giving the state of the art, with regard to direct reduction, smelting reduction, and the possibilities of « direct steel ». It concludes that three routes can be envisaged in the future.

Flooded areas are key information to crisis managers, both at local and national level. They help sizing human and material resources to be deployed before and during a flood. These data already exist on several French rivers as they are been produced in a legislative framework but mainly addressing the hundred-year flood. The purpose of the Flood Forecasting Services is to complete water levels forecasting published on www.vigicrues.gouv.fr with forecasting information on spatial flooded areas. State services are developing new flooded areas ranging from first overflows to the hundred-year floods. A national database called VIGInond provides secure web services to access these new data. It was developed in 2015. A key step in the standardization of these new data is the collaboration between various state services. The access to VIGInond is initially opened to the Ministry of Interior services. This first step allows the operators to test and to understand the impacts of forthcoming flooding. Once tested, it will be made available to other crisis managers through the forthcoming Vigicrues® portal version 2. The new data will be gradually included in Vigicrues® watercourses, while coastal areas and new watercourses will be subsequently added. These new information will increase awareness of flooding risks among stakeholders and citizens in the near future.

We describe the design, operation, and first results of a photometric calibration project, called DICE (Direct Illumination Calibration Experiment), aiming at achieving precise instrumental calibration of optical telescopes. The heart of DICE is an illumination device composed of 24 narrow-spectrum, high-intensity, light-emitting diodes (LED) chosen to cover the ultraviolet-to-near-infrared spectral range. It implements a point-like source placed at a finite distance from the telescope entrance pupil, yielding a flat field illumination that covers the entire field of view of the imager. The purpose of this system is to perform a lightweight routine monitoring of the imager passbands with a precision better than 5 per-mil on the relative passband normalisations and about 3{\AA} on the filter cutoff positions. The light source is calibrated on a spectrophotometric bench. As our fundamental metrology standard, we use a photodiode calibrated at NIST. The radiant intensity of each beam is mapped, and spectra are measured for each LED. All measurements are conducted at temperatures ranging from 0{\deg}C to 25{\deg}C in order to study the temperature dependence of the system. The photometric and spectroscopic measurements are combined into a model that predicts the spectral intensity of the source as a function of temperature. We find that the calibration beams are stable at the $10^{-4}$ level -- after taking the slight temperature dependence of the LED emission properties into account. We show that the spectral intensity of the source can be characterised with a precision of 3{\AA} in wavelength. In flux, we reach an accuracy of about 0.2-0.5% depending on how we understand the off-diagonal terms of the error budget affecting the calibration of the NIST photodiode. With a routine 60-mn calibration program, the apparatus is able to constrain the passbands at the targeted precision levels., Comment: 25 pages, 27 figures, accepted for publication in A&A

Charge-coupled devices (CCDs) are widely used in astronomy to carry out a variety of measurements, such as for flux or shape of astrophysical objects. The data reduction procedures almost always assume that ther esponse of a given pixel to illumination is independent of the content of the neighboring pixels. We show evidence that this simple picture is not exact for several CCD sensors. Namely, we provide evidence that localized distributions of charges (resulting from star illumination or laboratory luminous spots) tend to broaden linearly with increasing brightness by up to a few percent over the whole dynamic range. We propose a physical explanation for this "brighter-fatter" effect, which implies that flatfields do not exactly follow Poisson statistics: the variance of flatfields grows less rapidly than their average, and neighboring pixels show covariances, which increase similarly to the square of the flatfield average. These covariances decay rapidly with pixel separation. We observe the expected departure from Poisson statistics of flatfields on CCD devices and show that the observed effects are compatible with Coulomb forces induced by stored charges that deflect forthcoming charges. We extract the strength of the deflections from the correlations of flatfield images and derive the evolution of star shapes with increasing flux. We show for three types of sensors that within statistical uncertainties,our proposed method properly bridges statistical properties of flatfields and the brighter-fatter effect.