Agronomic and environmental impacts of a single application of heat-dried sludge on an Alfisol

A field experiment was conducted on Alfisols in South-West France to assess the agronomic and environmental impacts of a single application of heat-dried sludge pellets at 11.1 Mg dry matter ha-1. The sludge pellets, with a moisture level of 9.5%, were spread on an irrigated crop of maize (Zea mays L.). This treatment was compared with inorganic fertilization (urea and diammonium phosphate mixed with KCl). Soil properties, yield and the composition of maize and the quality of drained water were monitored over 1 year to detect any changes resulting from sludge application. Amongst several determined soil properties, only two were significantly modified by the sludge application: The nitric nitrogen stock of the soil was higher in the inorganic fertilized plot, whereas Olsen-P soil content was higher in the sludge-amended plot. Agronomic recovery rates of N and P added by sludge were high: For the first crop following application, total amounts of N and P supplied by the sludge had the same efficiency as approximately 45% of the N and P amounts supplied by inorganic fertilizer. This ratio was 7% for the N uptake by the second maize crop. The quality and quantity of maize were equally good with both types of fertilization. During the 2 years following sludge spreading, N leaching remained as low in the sludged plot as in the inorganically fertilized one. The Cu, Zn, Cr, Cd, Pb and Ni composition of the drainage water was affected by neither of the types of amendment. From the heavy-metal contents of the soil, water and maize monitored over 1 year in the field experiment and from literature data for cow manure and atmospheric emissions, a theoretical balance between crop soil heavy-metal input and output over one century was drawn up. The long-term impact of cow manure on Zn, Ni and Cr in soil is higher than that of the studied heat-dried sludge. Obviously, sludge tended to cause a strong increase in soil Cu storage, valued for these soils, which are otherwise very Cu deficient

On understanding the microstructure of SiC/SiC Ceramic Matrix Composites (CMCs) after a material removal process

The unique material nature (e.g. hard, brittle, heterogeneous and orthotropic) of SiC-based Ceramic Matrix Composites (CMCs) highly affects the outcomes of machining process by inducing high thermo-mechanical loads during material removal. This can result in severe material damage which in turn causes a reduction of the in-service life of critical structural ceramic components (such as in aero-engines or nuclear reactors). In this study, the phenomenon by which the material removal mechanism during drilling influences the CMC surface integrity are discussed by characterising the fracture and deformation phenomena on the CMC's constituents - i.e. SiC and Si materials. Moreover, the strain induced to the surface, together with the changes in chemical composition are characterised via micro Raman spectroscopy and related to the principles of residual stresses upon cutting. This results in a novel understanding of the material removal process that governs cutting of SiC-based CMCs while emphasising how the different microstructure, morphology and nature of ceramics behave under the same cutting conditions. This study has therefore led to a comprehension of how the microstructure of complex hierarchical ceramic materials such as SiC/SiC CMCs is affected by a mechanical cutting process and opens avenues to understand the structure damage under other machining operations (e.g. milling, grinding)

Suivi des introgressions dans les croisements interspécifiques chez le riz : utilisation des marqueurs moléculaires

La diversité génétique des espèces sauvages de riz est d'un grand intérêt en amélioration des plantes. Malgré de fortes barrières reproductives, des hybrides interspécifiques peuvent être obtenus grâce à la récupération des embryons par culture #in vitro et être recroisés ensuite pour introduire des caractères utiles dans les riz cultivés. Au fur et à mesure que la carte de liaison génétique RFLP (polymorphisme de longueur de fragment de restriction) devient de plus en plus saturée, les marqueurs moléculaires constituent un nouvel outil puissant pour analyser et comprendre les mécanismes de la recombinaison dans les croisements éloignés. Trois exemples d'application des marqueurs moléculaires au suivi des introgressions sont présentés à partir d'activités développées à l'ORSTOM (Institut Français de Recherche Scientifique pour le Développement en Coopération) de Montpellier ou de collaborations avec l'IRRI (Institut International de Recherche sur le Riz, Philippines) et l'Université Cornell (Etats-Unis). Ils concernent l'analyse de générations précoces ou de lignées isogéniques développées avec des espèces sauvages de riz possédant le même génome que le riz cultivé (#O. longistaminata) ou des génomes cytogénétiquement différents (#O. brachyantha, génome F) et (#O. australiensis, génome E). (Résumé d'auteur

Probabilistic modelling of tool unbalance during cutting of hard-heterogeneous materials: a case study in Ceramic Matrix Composites (CMCs)

Compared to other materials, CMCs display a unique high hardness and heterogeneous nature which are critically reflected during the drilling process where asymmetrical high forces are suffered by the tool, resulting in an unbalance of the drill bit. Hence, this study proposes a mechanistic approach where the hard nature resulting in high radial forces is analytically studied and coupled with a probabilistic model where the heterogeneous nature of CMCs is taken into consideration. This theoretical study results in an in-depth understanding of the loading unbalance occurring on different tool sizes during drilling of CMCs which can lead to a premature tool breakage. The nature of this unique force that is assumed in the theoretical approach to influence the cutting of hard-heterogeneous materials is experimentally validated by drilling a homogeneous and a heterogeneous hard ceramics, i.e. a monolithic SiC and a SiC/SiC CMC. Moreover, the model developed together the with drilling experiments with different tool diameters result in an understanding of why small tool diameters suffer a premature tool breakage when drilling difficult-to-machine CMCs

Real-time insight into the multistage mechanism of nanoparticle exsolution from a perovskite host surface

In exsolution, nanoparticles form by emerging from oxide hosts by application of redox driving forces, leading to transformative advances in stability, activity, and efficiency over deposition techniques, and resulting in a wide range of new opportunities for catalytic, energy and net-zero-related technologies. However, the mechanism of exsolved nanoparticle nucleation and perovskite structural evolution, has, to date, remained unclear. Herein, we shed light on this elusive process by following in real time Ir nanoparticle emergence from a SrTiO3 host oxide lattice, using in situ high-resolution electron microscopy in combination with computational simulations and machine learning analytics. We show that nucleation occurs via atom clustering, in tandem with host evolution, revealing the participation of surface defects and host lattice restructuring in trapping Ir atoms to initiate nanoparticle formation and growth. These insights provide a theoretical platform and practical recommendations to further the development of highly functional and broadly applicable exsolvable materials

Effects of adding Tiotropium or Aclidinium as triple therapy using impulse oscillometry in COPD

INTRODUCTION: Long-acting muscarinic antagonists confer improvements in spirometry when used in addition to inhaled corticosteroids and long-acting beta-agonists (ICS/LABA) in COPD. The dual objectives of this proof of concept study were to evaluate trough effects of tiotropium (TIO) or aclidinium (ACL) when used as triple therapy and to assess if impulse oscillometry (IOS) might be more sensitive than spirometry in detecting subtle differences in bronchodilator response. METHODS: Patients with moderate to severe COPD already taking ICS/LABA were randomized to receive add-on therapy in cross-over fashion with either TIO 18 µg od or ACL 322 µg bid for 2–3 weeks each. Measurements of IOS, spirometry, 6-min walk test, St George’s Respiratory Questionnaire (SGRQ) and Baseline/Transition Dyspnoea Index (TDI) were made at baseline and after chronic dosing at trough (12 h for ACL and 24 h for TIO), in addition to domiciliary diurnal spirometry. RESULTS: 13 patients were completed: mean age 69 years, FEV(1) 52 % predicted, FEV(1)/FVC 0.48, and R5 202 % predicted. There were no differences in any visit-based trough IOS or spirometry outcomes comparing TIO versus ACL. Resonant frequency but not total airway resistance at 5 Hz (R5) significantly improved from baseline with both treatments while peripheral airway resistance (R5–R20) significantly improved with ACL. Visit-based FEV(1), and forced and relaxed vital capacity were also significantly improved from baseline with both treatments. There were no significant differences in diurnal FEV(1) and FEV(6) profiles between treatments. 6-min walk distance and post-walk fatigue significantly improved from baseline with ACL, while post-walk dyspnea improved with TIO. SGRQ symptom score significantly improved to a similar degree with both treatments. TDI significantly improved with ACL versus TIO by 1.54 units. CONCLUSION: We observed comparable bronchodilator efficacy at trough with TIO and ACL when used as triple therapy in COPD, while IOS was no more sensitive than spirometry

Transiting exoplanets from the CoRoT space mission VIII. CoRoT-7b: the first Super-Earth with measured radius

We report the discovery of very shallow (DF/F = 3.4 10-4), periodic dips in the light curve of an active V = 11.7 G9V star observed by the CoRoT satellite, which we interpret as due to the presence of a transiting companion. We describe the 3-colour CoRoT data and complementary ground-based observations that support the planetary nature of the companion. Methods. We use CoRoT color information, good angular resolution ground-based photometric observations in- and out- of transit, adaptive optics imaging, near-infrared spectroscopy and preliminary results from Radial Velocity measurements, to test the diluted eclipsing binary scenarios. The parameters of the host star are derived from optical spectra, which were then combined with the CoRoT light curve to derive parameters of the companion. We examine carefully all conceivable cases of false positives, and all tests performed support the planetary hypothesis. Blends with separation larger than 0.40 arcsec or triple systems are almost excluded with a 8 10-4 risk left. We conclude that, as far as we have been exhaustive, we have discovered a planetary companion, named CoRoT-7b, for which we derive a period of 0.853 59 +/- 3 10-5 day and a radius of Rp = 1.68 +/- 0.09 REarth. Analysis of preliminary radial velocity data yields an upper limit of 21 MEarth for the companion mass, supporting the finding. CoRoT-7b is very likely the first Super-Earth with a measured radius.Comment: Accepted in Astronomy and Astrophysics; typos and language corrections; version sent to the printer w few upgrade

Efficacy and safety of once-daily aclidinium in chronic obstructive pulmonary disease

BACKGROUND: The long-term efficacy and safety of aclidinium bromide, a novel, long-acting muscarinic antagonist, were investigated in patients with moderate to severe chronic obstructive pulmonary disease (COPD). METHODS: In two double-blind, 52-week studies, ACCLAIM/COPD I (n=843) and II (n=804), patients were randomised to inhaled aclidinium 200 μg or placebo once-daily. Patients were required to have a post-bronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity ratio of ≤70% and FEV1<80% of the predicted value. The primary endpoint was trough FEV1 at 12 and 28 weeks. Secondary endpoints were health status measured by St George's Respiratory Questionnaire (SGRQ) and time to first moderate or severe COPD exacerbation. RESULTS: At 12 and 28 weeks, aclidinium improved trough FEV1 versus placebo in ACCLAIM/COPD I (by 61 and 67 mL; both p<0.001) and ACCLAIM/COPD II (by 63 and 59 mL; both p<0.001). More patients had a SGRQ improvement≥4 units at 52 weeks with aclidinium versus placebo in ACCLAIM/COPD I (48.1% versus 39.5%; p=0.025) and ACCLAIM/COPD II (39.0% versus 32.8%; p=0.074). The time to first exacerbation was significantly delayed by aclidinium in ACCLAIM/COPD II (hazard ratio [HR] 0.7; 95% confidence interval [CI] 0.55 to 0.92; p=0.01), but not ACCLAIM/COPD I (HR 1.0; 95% CI 0.72 to 1.33; p=0.9). Adverse events were minor in both studies. CONCLUSION: Aclidinium is effective and well tolerated in patients with moderate to severe COPD