191 research outputs found
Variations in the composition of the major elements of wheat varieties in industrial and organic farming systems: initial results
A nutritional analysis was added to the study of the characterization of wheat varieties in organic and industrial farming systems for the year 2005-2006. The experimental design consisted of three wheat varieties (Atrium, Ataro and Renan) and three densities (200, 400 and 600 grains/m2) on two soils representative of the Auvergne region. The parameters studied were productivity, technological suitability and nutritional value (N, P, K, Ca, Mg). The yield was particularly low for organic farming (23 q/ha), following unfavorable climatic conditions. In spite of the low yield under organic farming conditions, the Mg and P contents in the grains were normal. The low thousand-grain weight and the early maturity of Atrium did not make it possible to increase the nutritional density of the grains in 2006. These results must be confirmed so that we can propose a typology of varieties with high nutritional density linked to cropping practices and the environment. This typology will be used to make breads that are beneficial to our health
Challenges in Rotor Aerodynamic Modeling for Non-Uniform Inflow Conditions
Within an international collaboration framework, the accuracy of rotor
aerodynamic models used for design load calculations of wind turbines is being assessed. Where
the use of high-fidelity computation fluid dynamics (CFD) and mid-fidelity free-vortex wake
(FVW) models has become commonplace within the wind energy community, these still fail to
meet the requirements in terms of execution time and computational cost needed for design
load calculations. The fast but engineering fidelity blade-element/momentum (BEM) method
can therefore still be considered the industry workhorse for design load simulations.
At the same time, upscaling of wind turbine rotors makes inflow non-uniformities (e.g. shear,
veer, turbulence) more important. The objective of this work is to assess model accuracy in
non-uniform inflow conditions, which violate several BEM assumptions. Thereto a comparison
in turbulent inflow has been executed including a wide variety of codes, focusing on the DanAero
field measurements, where a 2.3-MW turbine was equipped with, among other sensors, a pressure
measurement apparatus. The results indicate that, although average load patterns are in good
agreement, this does not hold for the unsteady loads that drive fatigue damage and aeroelastic stability. A simplified comparison round in vertical shear was initiated to investigate
the observed differences in a more controlled manner. A consistent offset in load amplitude was
observed between CFD and free-vortex codes on the one hand and BEM-type codes on the other
hand. To shed more light on the observations, dedicated efforts are ongoing to pinpoint the cause
for these differences, in the end leading to guidelines for an improved BEM implementation
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Capture cavity II results at FNAL
As part of the research and development towards the International Linear Collider (ILC), several test facilities have been developed at Fermilab. This paper presents the latest Low Level RF (LLRF) results obtained with Capture Cavity II (CCII) at the ILC Test Accelerator (ILCTA) test facility. The main focus will be on controls and RF operations using the SIMCON based LLRF system developed in DESY [1]. Details about hardware upgrades and future work will be discussed
New Insights into the Organization, Recombination, Expression and Functional Mechanism of Low Molecular Weight Glutenin Subunit Genes in Bread Wheat
The bread-making quality of wheat is strongly influenced by multiple low molecular weight glutenin subunit (LMW-GS) proteins expressed in the seeds. However, the organization, recombination and expression of LMW-GS genes and their functional mechanism in bread-making are not well understood. Here we report a systematic molecular analysis of LMW-GS genes located at the orthologous Glu-3 loci (Glu-A3, B3 and D3) of bread wheat using complementary approaches (genome wide characterization of gene members, expression profiling, proteomic analysis). Fourteen unique LMW-GS genes were identified for Xiaoyan 54 (with superior bread-making quality). Molecular mapping and recombination analyses revealed that the three Glu-3 loci of Xiaoyan 54 harbored dissimilar numbers of LMW-GS genes and covered different genetic distances. The number of expressed LMW-GS in the seeds was higher in Xiaoyan 54 than in Jing 411 (with relatively poor bread-making quality). This correlated with the finding of higher numbers of active LMW-GS genes at the A3 and D3 loci in Xiaoyan 54. Association analysis using recombinant inbred lines suggested that positive interactions, conferred by genetic combinations of the Glu-3 locus alleles with more numerous active LMW-GS genes, were generally important for the recombinant progenies to attain high Zeleny sedimentation value (ZSV), an important indicator of bread-making quality. A higher number of active LMW-GS genes tended to lead to a more elevated ZSV, although this tendency was influenced by genetic background. This work provides substantial new insights into the genomic organization and expression of LMW-GS genes, and molecular genetic evidence suggesting that these genes contribute quantitatively to bread-making quality in hexaploid wheat. Our analysis also indicates that selection for high numbers of active LMW-GS genes can be used for improvement of bread-making quality in wheat breeding
A catalogue of Triticum monococcum genes encoding toxic and immunogenic peptides for celiac disease patients
The celiac disease (CD) is an inflammatory condition characterized by injury to the lining of the small-intestine on exposure to the gluten of wheat, barley and rye. The involvement of gluten in the CD syndrome has been studied in detail in bread wheat, where a set of “toxic” and “immunogenic” peptides has been defined. For wheat diploid species, information on CD epitopes is poor. In the present paper, we have adopted a genomic approach in order to understand the potential CD danger represented by storage proteins in diploid wheat and sequenced a sufficiently large number of cDNA clones related to storage protein genes of Triticum monococcum. Four bona fide toxic peptides and 13 immunogenic peptides were found. All the classes of storage proteins were shown to contain harmful sequences. The major conclusion is that einkorn has the full potential to induce the CD syndrome, as already evident for polyploid wheats. In addition, a complete overview of the storage protein gene arsenal in T. monococcum is provided, including a full-length HMW x-type sequence and two partial HMW y-type sequences
Characterizing HMW-GS alleles of decaploid Agropyron elongatum in relation to evolution and wheat breeding
Bread wheat quality is mainly correlated with high molecular weight glutenin subunits (HMW-GS) of endosperm. The number of HMW-GS alleles with good processing quality is limited in bread wheat cultivars, while there are plenty of HMW-GS alleles in wheat-related grasses to exploit. We report here on the cloning and characterization of HMW-GS alleles from the decaploid Agropyron elongatum. Eleven novel HMW-GS alleles were cloned from the grass. Of them, five are x-type and six y-type glutenin subunit genes. Three alleles Aex4, Aey7, and Aey9 showed high similarity with another three alleles from the diploid Lophopyrum elongatum, which provided direct evidence for the Ee genome origination of A. elongatum. It was noted that C-terminal regions of three alleles of the y-type genes Aey8, Aey9, and Aey10 showed more similarity with x-type genes than with other y-type genes. This demonstrates that there is a kind of intermediate state that appeared in the divergence between x- and y-type genes in the HMW-GS evolution. One x-type subunit, Aex4, with an additional cysteine residue, was speculated to be correlated with the good processing quality of wheat introgression lines. Aey4 was deduced to be a chimeric gene from the recombination between another two genes. How the HMW-GS genes of A. elongatum may contribute to the improvement of wheat processing quality are discussed
Presence of celiac disease epitopes in modern and old hexaploid wheat varieties: wheat breeding may have contributed to increased prevalence of celiac disease
Gluten proteins from wheat can induce celiac disease (CD) in genetically susceptible individuals. Specific gluten peptides can be presented by antigen presenting cells to gluten-sensitive T-cell lymphocytes leading to CD. During the last decades, a significant increase has been observed in the prevalence of CD. This may partly be attributed to an increase in awareness and to improved diagnostic techniques, but increased wheat and gluten consumption is also considered a major cause. To analyze whether wheat breeding contributed to the increase of the prevalence of CD, we have compared the genetic diversity of gluten proteins for the presence of two CD epitopes (Glia-α9 and Glia-α20) in 36 modern European wheat varieties and in 50 landraces representing the wheat varieties grown up to around a century ago. Glia-α9 is a major (immunodominant) epitope that is recognized by the majority of CD patients. The minor Glia-α20 was included as a technical reference. Overall, the presence of the Glia-α9 epitope was higher in the modern varieties, whereas the presence of the Glia-α20 epitope was lower, as compared to the landraces. This suggests that modern wheat breeding practices may have led to an increased exposure to CD epitopes. On the other hand, some modern varieties and landraces have been identified that have relatively low contents of both epitopes. Such selected lines may serve as a start to breed wheat for the introduction of ‘low CD toxic’ as a new breeding trait. Large-scale culture and consumption of such varieties would considerably aid in decreasing the prevalence of CD
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