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Fusarium head blight caused by different varieties of Fusarium species is one of the major serious worldwide diseases found in wheat production. It is therefore important to be able to quantify the deoxynivalenol concentration in wheat. Unfortunately, in mycotoxin quantification, due to the uneven distribution of mycotoxins within the initial lot, it is difficult, or even impossible, to obtain a truly representative analytical sample. In previous work we showed that the sampling step most responsible for variability was grain sampling. In this paper, it is more particularly the step scaling down from a laboratory sample of some kilograms to an analytical sample of a few grams that is investigated. The naturally contaminated wheat lot was obtained from an organic field located in the southeast of France (Rhône-Alpes) from the year 2008-2009 cropping season. The deoxynivalenol level was found to be 50.6 ± 2.3 ng g⁻¹. Deoxynivalenol was extracted with a acetonitrile-water mix and quantified by gas chromatography-electron capture detection (GC-ECD). Three different grain sampling techniques were tested to obtain analytical samples: a technique based on manually homogenisation and division, a second technique based on the use of a rotating shaker and a third on the use of compressed air. Both the rotating shaker and the compressed air techniques enabled a homogeneous laboratory sample to be obtained, from which representative analytical samples could be taken. Moreover, the techniques did away with many repetitions and grinding. This study, therefore, contributes to sampling variability reduction in the evaluation of deoxynivalenol contamination of organic wheat grain, and then, at a reasonable cost.

International audience; The predictive power of the last version INCL4.6 of the Liège Intranuclear Cascade model for spallation is reviewed. The good results obtained both at low and high energy extend the domain of validity of the model and allow the description of spallation reactions, except the coherent processes, by a unique model from a few MeV to a few GeV incident energy.

International audience; A crucial requirement in the development of liquid-metal spallation neutron target is knowledge of the composition and amount of volatile radionuclides that are released from the target during operation. It is also important to know the total amount produced, which could be released if there was an accident. One type is the lead-bismuth eutectic (LBE) target where different radionuclides can be produced following interaction with a high-energy proton beam, notably noble gases (Ar, Kr, Xe isotopes) and other relative volatile isotopes such as Hg and At. The results of an irradiation experiment performed at ISOLDE on a LBE target are compared with predictions from the MCNPX code using the latest developments on the Li'ege Intranuclear Cascade model (INCL4.6) and the CEM03 model. The calculations are able to reproduce the mass distribution of the radioisotopes produced, including the At production, where there is a significant contribution from secondary reactions. Subsequently, a post-irradiation examination of the irradiated target was performed. Investigations of both the tantalum target structure, in particular the beam window, and the leadbismuth eutectic were performed using several experimental techniques. No sign of severe irradiation damage, previously observed in other ISOLDE targets, was found.

This article examines the two consecutive approaches to the Shoah found in the works of Gunther Anders (1902-1992). First came the poems he wrote during his American exile in which he tries to get close to the experience of the pursued, deported Jews. Then came the approach having to do with the “obsolescence of man,” which situates the Shoah in the philosophical history of the relationship between humans and technology.

The new version (INCL4.6) of the Li`ege intranuclear cascade (INC) model for the description of spallation reactions is presented in detail. Compared to the standard version (INCL4.2), it incorporates several new features, the most important of which are: (i) the inclusion of cluster production through a dynamical phase space coalescence model, (ii) the Coulomb deflection for entering and outgoing charged particles, (iii) the improvement of the treatment of Pauli blocking and of soft collisions, (iv) the introduction of experimental threshold values for the emission of particles, (v) the improvement of pion dynamics, (vi) a detailed procedure for the treatment of light-cluster induced reactions taking care of the effects of binding energy of the nucleons inside the incident cluster and of the possible fusion reaction at low energy. Performances of the new model concerning nucleon-induced reactions are illustrated. Whenever necessary, the INCL4.6 model is coupled to the ABLA07 deexcitation model and the respective merits of the two models are then tentatively disentangled. Good agreement is generally obtained in the 200 MeV-2 GeV range. Below 200 MeV and down to a few tens of MeV, the total reaction cross section is well reproduced and differential cross sections are reasonably well described. The model is also tested for light-ion induced reactions at low energy, below 100 MeV incident energy per nucleon. Beyond presenting the update of the INCL4.2 model, attention has been paid to applications of the new model to three topics for which some particular aspects are discussed for the first time: production of clusters heavier than alpha particles, longitudinal residue recoil velocity and its fluctuations, total reaction cross section and the residue production cross sections for low energy incident light ions., Comment: 29 pages, 26 figures

International audience; Organic farming systems are often nutrient-limited. Moreover, even if organic guidelines emphasize the reliance on ecological processes and recycling, the trend towards farm specialisation induces an increased reliance on off-farm fertilising materials in arable areas. There is, therefore, a need to better understand the drivers of nutrient inflows on organic farms. Our objectives were to assess the nitrogen (N,) phosphorus (P) and potassium (K) farm-gate inflows through fertilising materials, and the nutrient budget and use efficiency over a large range of organic farming systems. To do this, 56 interviews with organic farmers concerning their nutrient management for the years 2010 and 2011 were carried out in 2012 in three French agricultural districts distributed over a gradient of farming activity. The results showed that the farm-gate fertilising material inflows were strongly related to both the ratio of land under cereal and oilseed crops (proxy of nutrient ‘demand’) and the stocking rate (proxy of nutrient ‘supply’). However, other inflows (biological N fixation, feed use, fodders and straws) increased with the stocking rate, leading to low farm-gate N and K use efficiency (0.2 and 0.7, respectively) on livestock farms compared to arable, stockless farms (1.4 and 3.5, respectively). Such results helped to disentangle the drivers of nutrient use in organic farms compared to previous analyses based solely on farm production typology.

ESSN: 1879-4246; International audience; Organic agriculture is a production system which relies on ecosystem management and ecological processes rather than on the external flow of agricultural inputs. The development of the organic sector has incluced a spatial decoupling of livestock and crop production. This has increased the flow of nutrients that occurs between farms compared to what happens within individual farms. Organic systems have replaced synthetic inputs with site-specific management practices to balance input and output nutrients to ensure short-term productivity and long-term sustainability. This paper addresses the nutrient management of mixed and specialized farming systems, with a special emphasis on the reliance on livestock production for the nutrient management of arable farmland. We assessed the nutrient budgets of nitrogen (N), phosphorus (P), and potassium (K) of 28 organic farms selected according to livestock density from three French countries. The farms were classified as stockless, mixed, and cattle farming systems. A soil surface nutrient budget was calculated for each farm based on inputs (N fixation, excreta, and manure) and outputs (grazing, offtake, harvests) on annual crops and grasslands. Inputs due to N atmospheric deposition and seeds and losses due to leaching and volatization were not considered in this study. Nutrient budgets of the 28 farms revealed N, P and K deficits, although disparities between farming systems and their geographical location were also observed. Stockless farms presented high N deficit whereas mixed and livestock farming systems presented lower deficits (close to equilibrium) or even surpluses in a county with a high density of livestock farms. Differences between farming systems in terms of P and K budgets followed the same trend, but regional specificities appreared significant in stockless and livestock systems (related to the size of farms and the stocking rate). None of the farms purchased off-farm organic fertilizers when exchanges of manures and straw were observed at the regional scale. When livestock is present on the farm, the nutrient resources came mainly from recycling internal resources (manures, excreta, and N fixation), whereas stockless farming systems purchased organic manure from neighboring farms ( 14 to 58 % of total N inputs, 10 to 100 % of total P and K inputs). The sustainability of stockless organic farming systems is questioned, noticeably those that were located in regions where resources of organic matter are scarce. Only farming systems producing large quantities of manure or which purchased feed showed balanced nutrient budgets.

In organic grain production, weeds are one of the major limiting factors along with crop nitrogen deficiency. Relay intercropping of forage legume cover crops in an established winter cereal crop might be a viable option but is still not well documented, especially under organic conditions. Four species of forage legumes (Medicago lupulina, Medicago sativa, Trifolium pratense and Trifolium repens) were undersown in six organic wheat fields. The density and aerial dry matter of wheat, relay-intercropped legumes and weeds were monitored during wheat-legume relay intercropping and after wheat harvest until late autumn, before the ploughing of cover crops. Our results showed a large diversity of aerial growth of weeds depending on soil, climate and wheat development. The dynamics of the legume cover crops were highly different between species and cropping periods (during relay intercropping and after wheat harvest). For instance, T. repens was two times less developed than the other species during relay intercropping while obtaining the highest aerial dry matter in late autumn. During the relay intercropping period, forage legume cover crops were only efficient in controlling weed density in comparison with wheat sole crop. The control of the aerial dry matter of weeds at the end of the relay intercropping period was better explained considering both legumes and wheat biomasses instead of legumes alone. In late autumn, 24 weeks after wheat harvest, weed biomass was largely reduced by the cover crops. Weed density and biomass reductions were correlated with cover crop biomass at wheat harvest and in late autumn. The presence of a cover crop also exhibited another positive effect by decreasing the density of spring-germinating annual weeds during the relay intercropping period. (C) 2013 Elsevier B.V. All rights reserved.

Wheat yields and grain protein content are lower and more variable in organic conditions than in conventional agriculture, mainly due to nitrogen (N) deficiency and weed competition. The undersowing of legume cover crops in growing winter wheat, also known as relay intercropping, is assumed to be a proficient way of enriching the soil-crop system with N and improving weed control. However, competition for resources may impair wheat performance. Relay intercropping in springtime in growing winter wheat is expected to limit competition for resources from the legume. The aim of our study was to analyze wheat performance and resource competition in relay intercropping systems with legume cover crops under various environmental conditions. Eight field experiments were conducted on organic grain-oriented farms located in southeast France. Black medic (Medicago lupulina), alfalfa (Medicago sativa), red clover (Trifolium pratense) and white clover (Trifolium repens), undersown at wheat tillering stage, were compared with a sole crop of winter wheat (Triticum aestivum cv. Lona). The aerial biomass of wheat and legumes and total N content of wheat were determined at both the flowering stage and harvest time of the wheat. The main trophic resources (water, N and light) were monitored at similar stages. Wheat grain yield and grain protein content were also measured. Sites were classified according to wheat sole crop performance at harvest to evaluate the effect of relay intercropping in the various conditions tested. In all but one of the thirty-two treatments, wheat grain yield was not significantly disturbed by relay intercropping whatever the aerial development of legumes. Abundant aerial development of legumes after flowering (>20% of the aerial biomass of wheat at harvest) was associated with a mean significant decrease in wheat grain protein content of 8.5% of the control treatment value, this occurring in one third of the situations. These ratios of aerial biomasses of legumes compared to wheat were also associated with reductions in soil moisture and wheat N uptake. The effect on the availability of trophic resources for wheat may have led to a decrease in grain protein content without having any effect on grain yield. Sites which registered a low performance for wheat sole crops were less negatively impacted by the presence and aerial development of legumes. The performance of the four legume species and the mechanisms of induced disturbance of resource availability are then discussed. Finally, we try to define ranges of legumes' development and resource availability in which wheat performance was maintained or limited. (C) 2013 Elsevier B.V. All rights reserved.

The influence of functional groups on the dynamics of exchange between a flowing bulk melt and the channel wall was studied for oligomeric polyolefins (up to C-16) using attenuated total reflectance Fourier transform infrared spectroscopy. Surface transport is dominated by adsorbed layers whose structure is determined by functional groups and chain length. There are two distinct time scales for surface transport, both of order minutes and surprisingly long for molecules of this size. The longer time scale, which is observed only with chain functionalities that are likely to interact directly with the surface, appears to be caused by removal of an adsorbed mono- or bilayer. The shorter time scale, which was reported previously by Dietsche et al. (1995) for the hexadecane/hexadecene system, appears to be caused by depletion of a more loosely-structured layer, but one in which the packing is still sufficiently different from that of the bulk to retard the dynamics.

To determine the impact parameter of heavy-ion collisions from the observables is of crucial importance for comparing the experimental results with theory. For central collisions all methods which rely on a single observable have failed. We propose to determine the impact parameter by a neural network. We find that a combination of three observables allows the determining of the impact parameter four times more accurate than a single observable. We investigate in detail which combination of observables provides the best results.

International audience; Liquid lead-bismuth eutectic (LBE) is often considered as a possible target in spallation neutron sources. Anexperiment has been performed in 2005 at ISOLDE (CERN), in which LBE has been irradiated by 1.0 and 1.4GeV protons and isotopes of astatine, a volatile precursor of Po, have been found. Until recently no modelwas able to reproduce this astatine production, which is due either to double charge exchange reactions,Bi(p,π-xn)At, or to secondary reactions induced by helium nuclei. Recently, both parts of the spallation modelcombination INCL4-Abla have been improved leading to the new versions, INCL4.6-ABLA07. In particular,an additional mechanism to produce light and intermediate mass fragments has been added and special carehas been paid to the low energy reactions. This paper first shows that all the basic features of the differentreactions leading to astatine production are well predicted by the new model. The model, implemented into abeta version of MCNPX2.7 is then used to simulate the ISOLDE experiment. A very good agreement with theexperimental data is observed.

International audience; In the framework of the European Spallation Source (ESS) project, works on ESS target design needcomputational tools and the validation of these tools must be done to estimate accuracy of the calculationresults. INCL4.6 and Abla07 have been implemented in a beta version of MCNPX2.7 to be able to use themwhen transport is needed as ESS spallation target design. Within ESS project, we decided to benchmark ourspallation model on excitation functions (p+W) to assess the reliability on a thin target according to theproduced isotope and the projectile energy. We focused on a list of hazardous nuclei given by previous ESScalculations and from previous experiments. These results, which can of course help to estimate uncertaintiesas designing ESS target, were supplemented by another benchmark done with a thick tungsten target andgiving isotope production along the beam axis and radially as well.

We use the tools of hybrid intranuclear-cascade/nuclear-de-excitation models to evaluate the sensitivity of several physical observables to the inclusion of a multifragmentation stage in the deexcitation chain and assess the need for a multifragmentation model in the quantitative description of p + 56 Fe and p + 136 Xe reactions at 1-GeV incident energy. We seek clear signatures of multifragmentation by comparing different state-of-the-art de-excitation models coupled with intranuclear-cascade models and by focusing on discriminating observables such as correlations and fragment longitudinal-velocity distributions. None of the considered observables can be unambiguously interpreted as a multifragmentation footprint. The experimental data are best described as originating from sequential binary decays. However, no de-excitation model can reproduce the experimental longitudinal-volocity distributions from 1-GeV p + 136 Xe.

This chapter is a first attempt to analyse bottlenecks and challenges of European organic bread wheat sector involving technical, political and market issues. From 2000, the organic grain market has largely increased in Western Europe. To balance higher consumer demand there is a need to increase organic production by a new transition and technical improvement. Bread wheat is grown in a variety of crop rotations and farming systems where four basic organic crop production systems have been defined. Weeds and nitrogen deficiency are considered to be the most serious threat inducing lowest grain yield under organic production. The choice of cultivar, green manure, fertilization and intercropping legumes – grain or forage – are efficient ways to obtain high grain quality and quantity. The economic viability of wheat production in Europe is also affected by subsidies from European Union agri-environmental programs. Support has been granted to organic farming since the beginning of the 1990s. Direct payments from European regulation combined with premium prices paid by consumers had compensated the lowest crop production. In the European Union, the current cycle of the Common Agricultural Policy (CAP) is due to end in 2013. Discussions are now under way to support the policy for the period 2014–2020. With the increasing consumer awareness of their food, the growth of the organic sector may continue in the near future. However, financial crisis in some countries may lead to stagnation or even decline of consumer demand. The development of the organic grain sector is actually confronted to others challenges as quality and safety value. Technological ways of milling and baking may also improve baking quality and nutritional value of organic flour, as well as it prevents mycotoxin contamination. For instance, milling process strongly influences flour characteristics. Stone milling improves nutritive value when characteristics remain very stable independently of the milling yield while flour characteristics from roller milling appear very susceptible to the milling yield. The economic efficiency of the bread wheat sector is also influences by the existence of an adequate marketing structure answering consumers’ requirements. This paper is a contribution of a multidisciplinary group of researchers involved in AGTEC-Org project using peer review, statistical data and interviews of key actors: farmers, advisers or experts (coreorganic.org/research/projects/agtec-org/index.html).

International audience; The present major agricultural issues are to feed the world and reduce negative environmental impacts. To this end, organic farming appears as a promising solution. However organic farming has several drawbacks such as difficult weed management. Indeed weeds can reduce crop yields. Therefore there is a need for improved decision support tools for weed management in organic farming. An existing weed competition model actually predicts the effect of early multispecies weed density, both on organic wheat yield loss and on the weed density at flowering stage. However main existing models do not take into account the activity of end-users, e.g. farmers, during model design. Therefore we analysed weed information acquisition by farmers using the dynamic environment theory to design a decision support system that takes into account end-users. We interviewed eight French organic farmers. We analysed interview data using a coding scheme inspired by dynamic environment theory. Our results show that weed quantity was the information most frequently collected by organic farmers both for short- and long-term crop management. This information was compatible with early weed density, the main input of the previously developed models. Findings also show that procedures for gathering information and processing depended on farmer profiles. We also show that a conceptual model based on dynamic situations and a coding structure were appropriate for taking into account the information elaborated by end-users. Finally we propose further design of a decision support system for tactical organic weed management using a participatory approach.

We use the tools of hybrid intranuclear-cascade/nuclear-deexcitation models to evaluate the sensitivity of several physical observables to the inclusion of a multifragmentation stage in the deexcitation chain and assess the need for a multifragmentation model in the quantitative description of $p$ + ${}^{\text{5}6}$Fe and $p$ + ${}^{\text{1}36}$Xe reactions at 1-GeV incident energy. We seek clear signatures of multifragmentation by comparing different state-of-the-art deexcitation models coupled with intranuclear-cascade models and by focusing on discriminating observables such as correlations and fragment longitudinal-velocity distributions. None of the considered observables can be unambiguously interpreted as a multifragmentation footprint. The experimental data are best described as originating from sequential binary decays. However, no deexcitation model can reproduce the experimental longitudinal-velocity distributions from 1-GeV $p$ + ${}^{\text{1}36}$Xe.

International audience; The MEGAwatt PIlot Experiment (MEGAPIE) project was started in 2000 to design, build, and operate a liquid lead-bismuth eutectic (LBE) spallation neutron target at the power level of 1 MW. The target was irradiated for 4 months in 2006 at the Paul Scherrer Institute in Switzerland. Gas samples wereextracted in various phases of operation and analyzed by g spectroscopy, leading to the determination of the main radioactive isotopes released from the LBE. Comparison with calculations performed using several validated codes (MCNPX2.5.0/CINDER’90, FLUKA/ORIHET, and SNT) yields the ratio between simulated in-target isotope production rates and experimental amounts released at any given time. This work underlines the weak points of spallation models for some released isotopes. Also, results provide relevant information for safety and radioprotection in an accelerator-driven system and more particularly for the gas management in a spallation target dedicated to neutron production facilities.

In central Brazil, the tropical savannah ecosystem known as Cerrado, small scale farmers (around 20 ha) occupy marginal land scattered among large commercial farms on wide plateaux. Close to 90 % of the agricultural land farmed by large holders in the Cerrado is managed under direct seeding mulch based cropping systems (DMC). However, this system is almost not used by small scale farmers of the same region, even if their soils are often very susceptible to degradation (erosion, losses of soil organic matter), and they crucially need to stabilize their corn production in other to insure sustainability. Since 2005, Embrapa and Cirad tried to develop, in interaction with small farmers of Unaí region (Minas Gerais), new DMC systems adapted to their conditions and compatible with their own objectives. However, even if those systems increase soil fertility significantly, they also often deeply modify crop management as well as the use of resources available at farm level. Such systems have thus strong consequences on economical, environmental or social aspects of the system, (Scopel et al., 2005).

Un projet départemental de prévention des TMS est né en 2003 à l’initiative du Service Médical Inter-entreprises de l’Anjou et de l’Action Régionale pour l’Amélioration des Conditions de Travail des Pays de Loire pour répondre aux difficultés des entreprises à mettre en place des projets efficaces et pérennes. Il réunit dans un engagement pour 5 ans, 6 entreprises volontaires qui en acceptent les exigences.Les acteurs institutionnels de prévention apportent, dans une approche pluridisciplinaire, une méthodologie de projet et la possibilité d’échanges et de retours d’expérience entre les entreprises. Cet accompagnement est orienté sur la constitution de groupes de travail animés par des consultants privés pour réfléchir sur des situations à risques de TMS et mettre en commun des décisions de changement.Après 3 ans de conduite du projet dans un abattoir de viande bovine, un processus d’appropriation est à l’œuvre. Les évaluations mettent en lumière des changements humains, organisationnels et techniques. Cette expérience interroge le rôle des acteurs institutionnels et l’intérêt de l’articulation entre les acteurs externes et internes à l’entreprise. A departmental musculoskeletal disorder (MSD) prevention project was begun in 2003 on the initiative of the Anjou inter-company medical service and the Regional action for the improvement of working conditions in the Pays de Loire to respond to companies’ difficulties in establishing effective and ongoing projects. It brought together 6 volunteer companies in a commitment to a 5-year agreement.The institutional prevention actors provide, in a multi-disciplinary approach, a project methodology and the opportunity for exchanges and feedback between the companies. This accompanying action focused on the creation of working groups led by private consultants to consider situations that could lead to musculoskeletal disorders and to share decisions for change.After the project had been conducted in a bovine slaughterhouse for 3 years, an adaptation process is now being carried out. The evaluations are revealing human, organizational and technical changes. This experiment questions the role of institutional actors and the interest of the link between external actors and actors inside the company. Un proyecto departamental de prevención de las lesiones músculo esqueléticas (LMS) nació en el 2003, a iniciativa del Servicio Médico Inter-empresas de Anjou y de la Acción Regional por la Mejora de las Condiciones de Trabajo de los Países de Loire. El proyecto reune, con un compromiso de 5 años, 6 empresas voluntarias que aceptaron las exigencias, con el fin dar respuesta a las dificultades que las empresas tienen para implementar proyectos eficaces y perennes. Los actores institucionales de prevención aportan en un enfoque pluridisciplinario, una metodología de proyecto y la posibilidad de intercambios y de retorno de experiencia entre las empresas. Este acompañamiento esta orientado a la constitución de grupos de trabajo animados por consultantes privados para reflexionar sobre situaciones a riesgo de LMS y para poner en común las decisiones de cambio. Luego de conducir el proyecto durante 3 años en un matadero de carne bovina, un proceso de apropiación esta en curso. Las evaluaciones muestran cambios individuales, organizacionales y técnicos. Esta experiencia interroga el rol de los actores institucionales y el interés de la articulación entre actores internos y externos a la empresa.

International audience; Organic agriculture could achieve the objectives of sustainable agriculture by banning the use of synthetic fertilizers and pesticides. However, organic crops generally show lower performances than conventional ones. In France, organic winter wheat production is characterized by low grain protein content. There is a crucial need for better understanding the variability of grain protein content, because millers require batches with values over 10.5% of dry matter. Here, a regional agronomic diagnosis was carried out to identify the limiting factors and crop management practices explaining the variability of grain protein content. The studied field network was a set of 51 organic winter wheat plots in south-eastern France. The mixed-model method was used for identifying and ranking the limiting factors and the crop management practices responsible for variation in limiting factors. Our results show that the grain protein content variation was mostly explained by the baking quality grade of the cultivar, crop nitrogen status and weed density at flowering. There was a positive correlation between grain protein content and both crop nitrogen status and weed density. To a lesser extent, climatic factors also explained grain protein content variability. A lower water stress increased grain protein content, whereas an increase in the photothermal quotient and daily temperature over 25 °C reduced grain protein content. In south-eastern France, grain protein content of organic winter wheat could be increased by improving fertilization management, using an improved baking quality grade cultivar, choosing a legume fodder crop as preceding crop, or by avoiding late sowing dates.

Impingement jets are known to be efficient mechanisms for the exchange of heat between fluid and structure. They are generally used in industry for cooling, heating or drying. Several experimental and numerical studies have been realized to study convective heat transfers and/or to correlate the convective heat transfers to the wall with the unsteady flow of the jet (O’Donovan et al. [9] [10]). But these studies have been performed at low Mach number whereas higher Mach number are found in industrial applications as fan cooling processes for instance (M = 0.5 to 0.8). So, we propose to study the influence of Mach number of the impingement flow, ranging from 0.1 to 0.8, on convective heat exchange between a circular jet and a round axisymmetric plate. The aerodynamic of the fluid and the heat transfers depend on the following parameters: the D hydraulic diameter of the jet, the H distance to the wall, the Re Reynolds number of the flow, the M Mach number and the Tj temperature of the jet. The local convective heat transfer coefficients are experimentally determined by an inverse method based on a measurement of steady state temperature fields by infrared thermography (Fenot et al. [2]) for 1 ≤ H/D ≤ 5 and 0.1 ≤ M ≤ 0.8 . An experimental study of radial velocity fluctuations of the fluid in nearby wall has also been realized from hot wire anemometry. A spatial and temporal turbulent study (turbulence spectrum, integral turbulent scales, dissipation rate) allows to correlate convective heat transfer to the wall to aerodynamic phenomena.Copyright © 2008 by ASME

International audience; The development of sustainable cropping systems is a key priority for agronomists and crop scientists. A first step involves understanding the relationship between cropping system performance and farmers’ practices. To complete this step, a methodological framework entitled Regional Agronomic Diagnosis (RAD) has been developed. During the last ten years, the scope of the regional agronomic diagnosis has been enlarged to include several factors describing crop quality and the environmental impact of cropping systems. Regional agronomic diagnosis has led to several major advances such as (1) the assessment of the effect of preceding crop and soil structure on malting barley quality in France and (2) the assessment of the effects of ploughing, nematicide use and fertilisers on soil properties in intensive banana plantations in the West Indies. Improvements have also been gained in methodology, particularly by the selection of indicators for assessing the effects of crop management, soil and weather conditions, and data analysis. Finally, regional agronomic diagnosis has been integrated into more general approaches of agricultural development. We review here this methodological progress.

Conservation tillage covers a range of tillage practices, mostly non-inversion, which aim to conserve soil moisture and reduce soil erosion by leaving more than one-third of the soil surface covered by crop residues. Organic farmers are encouraged to adopt conservation tillage to preserve soil quality and fertility and to prevent soil degradation – mainly erosion and compaction. The potential advantages of conservation tillage in organic farming are reduced erosion, greater macroporosity in the soil surface due to larger number of earthworms, more microbial activity and carbon storage, less run-off and leaching of nutrients, reduced fuel use and faster tillage. The disadvantages of conservation tillage in organic farming are greater pressure from grass weeds, less suitable than ploughing for poorly drained, unstable soils or high rainfall areas, restricted N availability and restricted crop choice. The success of conservation tillage in organic farming hinges on the choice of crop rotation to ensure weed and disease control and nitrogen availability. Rotation of tillage depth according to crop type, in conjunction with compaction control measures is also required. A high standard of management is required, tailored to local soil and site conditions. Innovative approaches for the application of conservation tillage, such as perennial mulches, mechanical control of cover crops, rotational tillage and controlled traffic, require further practical assessment.

We measured integral thin target cross sections for the proton-induced production of He-, Ne-, and Ar- isotopes from Fe and Ni and of He-, Ne-, Ar-, Kr-, and Xe-isotopes from Bi from the respective reaction thresholds up to 2.6GeV. Iron and Ni are important structural materials for the planned ADS/EA systems and Bi is a major constituent for planned spallation neutron sources. In addition, we give new data for the production of 3 He from Mg, Al, Si, and Pb by revising earlier data and considering now 3 Hd iffusive losses and new information for the 3 H/ 3 He branching ratios. The data are compared to results from theoretical nuclear model codes.

The prescription of a psychotropic drugs to an adolescent is a high-risk prescription that raises numerous issues, imposing a rigorous evaluation of the expected benefit compared with the results that could be obtained by another approach, and the risk of interference with the spontaneous changes inherent to the process of adolescence. If sedatives, anxiolytics and psychostimulants are proscribed, it is possible in the case of absolute necessity, to prescribe neuroleptics and antidepressants. In this case, the medications should be prescribed in efficacious doses, should be the object of negotiation with the adolescent and his parents, and must never be prescribed at the first consultation nor, in any case, consist of the sole therapeutic intervention. It imposes a regular follow-up of the adolescent to assess compliance and to detect possible suicidal ideation.

In this article we present the development of a new photonuclear activation library for the CINDER’90 evolution code (LANL). The IAEA evaluations for 164 isotopes are explicitly included and more than 600 isotopes are added using the HMS‐ALICE predictions. GNASH evaluations are used in the case of actinides.

A survey is given about efforts undertaken during the HINDAS project to investigate the energy dependence of residual nuclide production by proton‐induced reactions from thresholds up to 2.6 GeV. For proton‐induced reactions, our experiments aimed to further develop and complete the cross‐section database that was established by our collaboration in recent years. It was extended to the heavy‐target elements Ta, W, Pb, and Bi for energies up to 2.6 GeV. In addition, new measurements for the target element iron were performed up to 2.6 GeV and for natural uranium for energies from 21 MeV to 69 MeV. For the target element lead, a comprehensive set of excitation functions published recently was completed by AMS‐measurements of cross sections for the production of the long‐lived radionuclides Be‐10, Al‐26, Cl‐36, and I‐129 and by mass spectrometric measurements for stable and radioactive rare gas isotopes of He, Ne, Ar, Kr, and Xe. Comprehensive tests of the nuclear‐reaction codes TALYS and INCL4+ABLA, which were developed within the HINDAS project, were performed with the new experimental results over the entire energy range.

The next generation spallation neutron sources, neutrino factories or RIB production facilities currently being designed and constructed world wide will increase the average proton beam power on target by a few orders of magnitude. Increased proton beam power results in target thermal hydraulic issues leading to new target designs, very often based on liquid metal technologies such as Hg, Pb, or PbBi. Radioactive nuclides produced in liquid metal targets are transported into hot cells, into pumps or close to electronics with radiation sensitive components. Besides the considerable amount of photon activity in the irradiated liquid metal, a significant amount of the Delayed Neutron (DN) precursor activity can be accumulated in the target fluid. The transit time from the front of a liquid metal target into areas, where DNs may be important, can be as short as a few seconds, i.e. well within one half‐life of many DN precursors. Therefore, it seems very important to evaluate the DN flux as a function of position and determine if DNs may contribute significantly to the activation and dose rates. The multi‐particle transport code MCNPX combined with the material evolution program CINDER’90 is used to predict the DN precursors and construct the DN tables. These DN tables are employed within the generalized geometrical model of the MegaPie spallation target at PSI (Switzerland). We show that the contribution of DNs and prompt spallation neutrons to the total neutron flux is comparable at the very top of the liquid PbBi loop. We also demonstrate that these estimates of DNs within MCNPX are very much model‐dependent. No experimental data are available for DN yields and time spectra from high energy fission‐spallation reactions. An experiment to perform these measurements is proposed.

This article presents calculations of photonuclear reaction cross sections for actinides by using different reaction codes, namely an improved version of HMS‐ALICE and GNASH. The GDR parameters from the RIPL2 data library are used to describe the total photo‐absorption cross section. In general, our results show satisfactory agreement with experimental data and IAEA evaluations. We plan to include our GNASH evaluations for 235U, 238U, 237Np, 239Pu, 240Pu and 241Am into a new release of the ENDF‐B/VII data files.

International audience; A diagnostic method for assessing regional variations in yield was implemented for a network of 24 organic wheat fields located in two neighboring regions, Diois and Val de Drôme (France). We studied: yield and its components; field environmental conditions of the fields; relations between indicators of potential limiting factors and yield components; and linkages between crop management and yield-limiting factors. The yield performances were low and variable (3.5 ± 1.4 t*ha-1). The relative kernel number (RKN) was significantly related to nitrogen nutrition and weed density at flowering. The nitrogen nutrition index (NNIf) had a strong and positive effect on relative kernel number, while weed density (1/WF) had a negative effect. The percentage of kernel number variation explained by the regression model (RKN = 0.112 + 0.609 × NNIf + 0.2 × 1/WF) was adequate (Adj. R2 = 0.53) with a RMSE of 0.09. The duration of the period of grain filling, reflected in the temperature sum, had a strong and positive effect on relative kernel weight (RTKW), while soil compaction and high temperature had a negative influence. Adjusted R2 for the model was 0.42 with a RMSE of 0.16. The results confirm that legumes preceding crops improve nitrogen nutrition on subsequent winter wheat, e.g. the Nitrogen Nutrition Index at flowering (NNIf) = 0.51 ± 0.12 for a crop rotation with a rate of legumes over 37% vs. 0.41 ± 0.11 for a crop rotation with a rate of legumes under 25%. Alfalfa preceding crops significantly limited the weed density at harvest while stony soils and early sowing (before November 1st) enhanced weed density.

Experimental and theoretical studies were performed to complete the data sets on the production of residue nuclides in natural Bi irradiated with protons. For the long-lived and difficult to measure isotopes 108mAg, 10Be, 26Al as well as 129I and 36Cl, chemical systems had been developed aimed to isolate them from the bismuth matrix. The separation methods are based on distillation, precipitation and ion exchange. From the content of the radionuclides determined by accelerator mass spectrometry and γ-spectrometry, the production cross sections in the proton energy range from 100 to 2600 MeV were calculated. The experimental results were compared with theoretical predictions. Significant deviations between experiment and theory over the whole energy range were observed with increasing discrepancies for the production of the lighter residue nuclides.

A la fin des annees 1920, Gunther Anders (1902-1992), ancien etudiant de Husserl et de Heidegger, adhere au projet d’une anthropologie philosophique (Scheler et Plessner) en lui donnant une dimension plus metaphysique que descriptive. Il pousse cette approche a la limite, de diverses facons, mais lui reste neanmoins fidele jusqu’au cœur des deux tomes de son opus magnum L’obsolescence de l’homme (1956 et 1980), et ce pour des raisons pratiques : a une epoque ou l’on proclame theoriquement la mort de l’homme et ou l’humanite s’est dotee d’un arsenal nucleaire capable de l’aneantir reellement, on ne peut que rester fidele a l’anthropologie.

Parasitological diagnosis, using staned smears, culture and pathological examination of biopsy, was studied in 146 patients infected with mucocutaneous leishmaniasis, in Bolivia and Peru. The most efficient parasite detecting technique appeared to be the smear examination in cutaneous lesions (33 % positive) and the pathology in case of mucous lesions (28 % positive). In both, cutaneous and mucous lesions, the parasites were found most frequently in old lesions.Diagnósticoparasitolôgico, usando esfregaço, cultura e exame anatomopatológico de biópsia, foi estudado em 146pacientes infectados com leishmaniose mucocutânea, na Bolívia e Peru. A mais eficiente técnica de detectar parasitas parece ser o exame de esfregaço para lesões cutâneas (33% de positividade) e anatomopatológico para lesões de mucosas (28% de positividade). Em ambas lesões, cutânea e mucosa, parasitas foram mais frequentemente encontrados em velhas lesões.

De tout temps et dans toutes les cultures, les femmes ont desire accoucher dans un espace intime et securitaire. Par l’apport des techniques et des progres obstetricaux, des le milieu du XXe siecle, bien que physiologique, la naissance se generalise dans le champ medical. Face au discours scientifique du personnel soignant, nous avons voulu mettre en echo les propos profanes des femmes, afin de comprendre les differentes facons d’interpreter le choix d’un lieu ideal pour accoucher. Chaque partie, medicale et profane, a sa facon, avec ses mots et ses croyances culturelles propres tente de donner sens a la representation savante ou emotionnelle du lieu d’accouchement. Le champ d’analyse de cet article repose sur des temoignages informels collectes au cours d’une enquete dans trois maternites de la region parisienne.