Simulation of winter wheat yield and its variability in different climates of Europe: A comparison of eight crop growth models

We compared the performance of eight widely used, easily accessible and well-documented crop growth simulation models (APES, CROPSYST, DAISY, DSSAT, FASSET, HERMES, STICS and WOFOST) for winter wheat (Triticum aestivum L.) during 49 growing seasons at eight sites in northwestern, Central and southeastern Europe. The aim was to examine how different process-based crop models perform at the field scale when provided with a limited set of information for model calibration and simulation, reflecting the typical use of models for large-scale applications, and to present the uncertainties related to this type of model application. Data used in the simulations consisted of daily weather statistics, information on soil properties, information on crop phenology for each cultivar, and basic crop and soil management information. Our results showed that none of the models perfectly reproduced recorded observations at all sites and in all years, and none could unequivocally be labelled robust and accurate in terms of yield prediction across different environments and crop cultivars with only minimum calibration. The best performance regarding yield estimation was for DAISY and DSSAT, for which the RMSE values were lowest (1428 and 1603 kg ha−1) and the index of agreement (0.71 and 0.74) highest. CROPSYST systematically underestimated yields (MBE – 1186 kg ha−1), whereas HERMES, STICS and WOFOST clearly overestimated them (MBE 1174, 1272 and 1213 kg ha−1, respectively). APES, DAISY, HERMES, STICS and WOFOST furnished high total above-ground biomass estimates, whereas CROPSYST, DSSAT and FASSET provided low total above-ground estimates. Consequently, DSSAT and FASSET produced very high harvest index values, followed by HERMES and WOFOST. APES and DAISY, on the other hand, returned low harvest index values. In spite of phenological observations being provided, the calibration results for wheat phenology, i.e. estimated dates of anthesis and maturity, were surprisingly variable, with the largest RMSE for anthesis being generated by APES (20.2 days) and for maturity by HERMES (12.6). The wide range of grain yield estimates provided by the models for all sites and years reflects substantial uncertainties in model estimates achieved with only minimum calibration. Mean predictions from the eight models, on the other hand, were in good agreement with measured data. This applies to both results across all sites and seasons as well as to prediction of observed yield variability at single sites – a very important finding that supports the use of multi-model estimates rather than reliance on single model

Mecanismes de transactivation du promoteur E2a d'adenovirus par l'oncogene E1a et la proteine E4

SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : T 83127 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Photosynthetic Light Reactions in Diatoms. II. The Dynamic Regulation of the Various Light Reactions

International audiencePhotosynthesis in diatoms is performed using the same basic modules as cyanobacteria and plants. It can be regulated on multiple levels depending on the environmental cues, allowing diatoms to adjust their photosynthetic light reaction towards optimum whilst at the same time minimizing photodamage induced by light. In recent years, tremendous progress has been gained in understanding these acclimation processes, revealing several diatom-specific features. In this chapter, we trace several paths through the photosynthetic electron transport chain to optimize photosynthesis. We review how diatoms repair photoinactivated reaction centers and which mechanisms they have to preempt photodamage. Finally, photoprotection is set in an ecophysiological context, highlighting differences in photoprotection of diatoms from different habitats

Photosynthetic Light Reactions in Diatoms. I. The Lipids and Light-Harvesting Complexes of the Thylakoid Membrane

International audienceLight harvesting and photochemistry is performed by photosystems coupled to specific antennae embedded in the thylakoid membrane, a common principle across diatoms, plants and green algae. Still, unique features of diatoms within this common principle have been unraveled in recent decades, likely resulting from the complex evolutionary history of diatoms. These unique features are found in (i) the lipid composition of the thylakoid membrane, ii) the spatial organization of the light harvesting complexes, and iii) their protein and pigment composition. This chapter summarizes current knowledge of these three specific features, with a focus on structural and functional properties

Severe skin lesions cause patients with inflammatory bowel disease to discontinue anti-tumor necrosis factor therapy.

BACKGROUND & AIMS: Psoriasiform and eczematiform lesions are associated with anti-tumor necrosis factor (TNF)-alpha therapies. We assessed clinical characteristics, risk factors, and outcomes of skin disease in patients with inflammatory bowel diseases that presented with psoriasiform and eczematiform lesions induced by anti-TNF-alpha agents. METHODS: We studied 85 patients (69 with Crohn's disease, 15 with ulcerative colitis, and 1 with indeterminate colitis; 62 women) with inflammatory skin lesions (62 psoriasiform and 23 eczematiform lesions). RESULTS: Twenty-four patients had a history of inflammatory skin lesions and 15 had a familial history of inflammatory skin disease. Locations of eczematiform lesions varied whereas scalp and flexural varieties were mostly psoriasiform. Skin lesions emerged but inflammatory bowel disease was quiescent in 69 patients following treatment with any type of anti-TNF-alpha agent (60 with infliximab, 20 with adalimumab, and 5 with certolizumab). Topical therapy resulted in partial or total remission in 41 patients. Patients with psoriasiform lesions that were resistant to topical therapy and that changed anti-TNF-alpha therapies once or twice developed recurring lesions. Overall, uncontrolled skin lesions caused 29 patients to stop taking TNF-alpha inhibitors. CONCLUSIONS: Inflammatory skin lesions following therapy with TNF-alpha inhibitors occurred most frequently among women and patients with a personal or familial history of inflammatory skin disease; lesions did not correlate with intestinal disease activity. Recurring and intense skin lesions caused 34% of patients in this study to discontinue use of anti-TNF-alpha agents

Crohn's disease stable remission after human immunodeficiency virus infection

We retrospectively assessed the clinical course in four patients with long-standing Crohn's disease who became infected with human immunodeficiency virus (HIV), The duration of active Crohn's disease was 21, 10, 4, and 4 years in our four patients, They experienced a stable remission of Crohn's disease symptoms after HIV infection, In three patients Crohn's disease was in stable remission for 5, 8, and 8 years after HIV infection and all three died from acquired immunodeficiency syndrome-related disease. One patient was still alive without recurrence of Crohn's disease symptoms 7 years following HIV detection, Our observations of a spontaneous improvement in the clinical course of Crohn's disease after HIV infection, suggests that the integrity of the immune response, especially that of CD4 T cells, plays a major role in the tissue injury mechanism in Crohn's disease

Clinical profile and prognostic significance of natriuretic peptide trajectory following hospitalization for worsening chronic heart failure: findings from the ASTRONAUT trial

International audienceAIMS:The purpose of this study was to determine the prognostic significance and associated clinical profile of early post-discharge N-terminal pro-B-type natriuretic peptide (NT-proBNP) trajectory among patients hospitalized for worsening chronic heart failure (HHF).METHODS AND RESULTS:This post-hoc analysis of the Aliskiren Trial in Acute Heart Failure Outcomes (ASTRONAUT) included 1351 HHF patients with ejection fraction (EF) ≤40%, elevated B-type natriuretic peptide ≥400 pg/mL or NT-proBNP ≥1600 pg/mL at admission, and available NT-proBNP measurements (from a central core laboratory) at baseline (median 5 days after admission) and 1-month follow-up. The co-primary endpoints were all-cause mortality and cardiovascular mortality or HHF within 12 months. Median follow-up was 11.3 months. Patients with decreasing post-discharge NT-proBNP trajectory tended to be younger and have non-ischaemic HF aetiology. The presence of baseline atrial fibrillation was associated with high NT-proBNP at 1 month (i.e. above the median), regardless of the baseline value. After adjustment for patient characteristics and 1-month NT-proBNP level, every twofold increase in continuous NT-proBNP change from baseline to 1 month was predictive of increased cardiovascular mortality or HHF (hazard ratio 1.14; 95% confidence interval 1.02-1.26), but not all-cause mortality (hazard ratio 0.95; 95% confidence interval 0.81-1.11).CONCLUSION:In this cohort of HHF patients with reduced EF, early post-discharge NT-proBNP trajectory was associated with a distinct clinical profile and carried independent prognostic value after adjustment for patient characteristics and absolute NT-proBNP level. Future prospective study of serial NT-proBNP measurement during the hospital and early post-discharge periods is warranted to validate these findings and evaluate post-discharge NT-proBNP trajectory as a therapeutic target

Cyclic nucleotide phosphodiesterase type 4 inhibitors : evaluation of pyrazolo [1,5-a]-1,3,5-triazine ring system as an adenine bioisostere.

A series of 8-substituted pyrazolo[1,5-a]-1,3,5-triazines were considered as a bioisosteric replacement for the 9-substituted adenine derivatives resulting in the discovery of 8-(2-methoxybenzyl)-4-(N-methylamino)-2-n-propylpyrazolo[1,5-a]-1,3,5-triazine (14d) and 2-trifluoromethyl-8-(2-methoxybenzyl)-4-(N-methylamino)pyrazolo[1,5-a]-1,3,5-triazine (14e) as a new structural class of potent phosphodiesterase type 4 inhibitors (IC50 = 13 nM and 11 nM, respectively) with high isoenzyme selectivity. An original tandem of reactions involving a palladium-mediated cross-coupling reaction (PMCCR) of the readily available 8-iodo-2-methyl-4-(N-methyl-N-phenylamino)pyrazolo[1,5-a]-1,3,5-triazine (11a) and arylboronic acids or alkynes followed by the displacement of the N-methyl-N-phenylamino group constitute the key steps in a novel synthetic approach developed herein. The treatment of 11a–c with n-BuLi and selected aldehydes represents an interesting alternative to the PMCCR for the synthesis of benzylic derivatives 14a–i. Preliminary biological testing has shown that compounds 14d and 14e strongly inhibit LPS-induced TNFα release from human mononuclear cells from healthy subjects. These two compounds were selected for further biological evaluation. Some derivatives belonging to the series of pyrazolo[1,5-a]-1,3,5 triazines act as adenine bioisosteres and present potent and selective PDE4 inhibitory properties