Grain filling

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Participation of green organs to grain filling in triticum turgidum var durum grown under mediterranean conditions

Participation of green organs to grain filling in triticum turgidum var durum grown under mediterranean conditions

2.2. Effect of Shading and Excision Treatments on Grain Filling The decrease of TKW (expressed in % of the control plants) in the different seasons and treatments is presented in Figure 1 for the cultivars Casablanca 7580 and Caravaca Colorado. In both genotypes, TKW was higher in Season 2 than in Season 1. Stem, ear and plant shading led to a significant reduction of TKW, independently of the season or cultivar. Ear shading, however, was associated with a higher decline in TKW than stem shading. The reduction in TKW induced by ear shading was 21.7% and 26.3% in Casablanca 7580 and Caravaca Colorado, respectively, in Season 1, and 21.4% and 31.3% in Season 2. Average TKW reduction across all treatments involving ear shading (treatments B, F, G and N) was similar in Casablanca 7580 and Caravaca Colorado in Season 1 (36.3% and 35.5%, respectively). Conversely, in Season 2, the average TKW for ear shading treatments was 35.8% lower in Casablanca 7580 and 46.5% lower in Caravaca Colorado compared to the control plants. Awn excision reduced TKW to the same extent in Casablanca 7580 (37.8%) and Caravaca Colorado (39.0%) in Season 1, but had a higher impact on Caravaca Colorado (46.9%) than Casablanca 7580 (38.5%) in Season 2. Flag leaf excision affected similarly the two cultivars. The contribution to grain filling (in %) of stem, flag leaf, spike and awns, estimated from different treatments, is presented in Table 3 for the two cultivars. The major contribution to grain filling came from stem and spike that participated oSn average (both through photosynthesis and re-mobilization) for more than 70% to final grain weight. Contribution of spike and stem photosynthesis showed a broad variation with values ranging from 9.5% to 41.6% and 2.3% to 57.8%, respectively, while flag leaf photosynthesis contributed less than 12.2%. The participation of ear (spike and awns) to grain filling was also high, but spike participated more than awns, particularly in photosynthesis. The participation of flag leaf (both through photosynthesis and re-mobilization) was lower than the participation of awns. The contribution of the spike was slightly increased in Season 2, compared to Season 1. The contribution of stem, although similar in both seasons in Caravaca Colorado, was much higher in Casablanca 7580 in Season 2 than in Season 1.
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Ear Rachis Xylem Occlusion and Associated Loss in Hydraulic Conductance Coincide with the End of Grain Filling for Wheat

Ear Rachis Xylem Occlusion and Associated Loss in Hydraulic Conductance Coincide with the End of Grain Filling for Wheat

Research efforts have focused so far mainly on the physiological consequences of grain dehydration on grain growth and several hypotheses may explain how it may impair grain filling. The mechanisms triggering the sudden grain dehydration at the end of the filling phase have received much less attention. The objective of our study was to unravel these mechanisms in wheat. Our analysis is based on the timing of the successive physiological modifications occurring after anthesis. As far as, we know there are no reports in the literature of the changes in hydraulic properties of cereal inflorescence during their development. Therefore, the present work is an attempt to find out how hydraulic conductance in wheat stem internodes, intact ear, rachis and grains change during development, and to investigate the relationship between hydraulic conductance and water loss during grain maturation. We hypothesize that (1) water flow through the xylem declines markedly during the latter stages of grain development; and (2) that this reduction results from embolism or xylem occlusion in the rachis and/or in the stem.
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Contribution of Different Organs to Grain Filling in Durum Wheat under Mediterranean Conditions I. Contribution of Post-Anthesis Photosynthesis and Remobilization

Contribution of Different Organs to Grain Filling in Durum Wheat under Mediterranean Conditions I. Contribution of Post-Anthesis Photosynthesis and Remobilization

Under Mediterranean conditions, drought affects cereals production principally through a limitation of grain filling. In this study, the respective role of post anthesis photosynthesis and carbon remobilization and the contribution of flag leaf, stem, chaff and awns to grain filling were evaluated under Mediterranean conditions in durum wheat (Triticum turgi.dum var. durum) cultivars. For the purpose, we examined the effects of shading and excision of different parts of the plant and compared carbon isotope discrimination (Li) in d ry matter offlag leaf, stem, chaff, awns and grain at maturity and in sap of stem, flag leaf, chaff and awns, this last measurement providing information on photosynthesis during a short period preceding sampling. Source sink manipulations and isotopie imprints of different organs on final isotope composition of the grain confirmed the high contribution of both carbons assimilated by ears and remobilized from stems to grain filling, and the relatively low contribution of leaves to grain filling. Grain Li was highly and significantly associated with grain yield across treatments, suggesting the utilization of this trait as an indicator of source sink manipulations effects on grain yield. Chaff and awns Li were better correlated with grain Li than stem and leaf Li, indicating that chaff were more involved in grain filling than other organs. Moreover, in chaff, sap Li was highly significantly correlated with d ry matter Li. These results suggest the use of Li for a rapid and non destructive estimation of the variation in the contribution of different organs to grain filling.
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Participation of green organs to grain filling in Triticum turgidum var durum grown under mediterranean conditions

Participation of green organs to grain filling in Triticum turgidum var durum grown under mediterranean conditions

2.2. Effect of Shading and Excision Treatments on Grain Filling The decrease of TKW (expressed in % of the control plants) in the different seasons and treatments is presented in Figure 1 for the cultivars Casablanca 7580 and Caravaca Colorado. In both genotypes, TKW was higher in Season 2 than in Season 1. Stem, ear and plant shading led to a significant reduction of TKW, independently of the season or cultivar. Ear shading, however, was associated with a higher decline in TKW than stem shading. The reduction in TKW induced by ear shading was 21.7% and 26.3% in Casablanca 7580 and Caravaca Colorado, respectively, in Season 1, and 21.4% and 31.3% in Season 2. Average TKW reduction across all treatments involving ear shading (treatments B, F, G and N) was similar in Casablanca 7580 and Caravaca Colorado in Season 1 (36.3% and 35.5%, respectively). Conversely, in Season 2, the average TKW for ear shading treatments was 35.8% lower in Casablanca 7580 and 46.5% lower in Caravaca Colorado compared to the control plants. Awn excision reduced TKW to the same extent in Casablanca 7580 (37.8%) and Caravaca Colorado (39.0%) in Season 1, but had a higher impact on Caravaca Colorado (46.9%) than Casablanca 7580 (38.5%) in Season 2. Flag leaf excision affected similarly the two cultivars. The contribution to grain filling (in %) of stem, flag leaf, spike and awns, estimated from different treatments, is presented in Table 3 for the two cultivars. The major contribution to grain filling came from stem and spike that participated oSn average (both through photosynthesis and re-mobilization) for more than 70% to final grain weight. Contribution of spike and stem photosynthesis showed a broad variation with values ranging from 9.5% to 41.6% and 2.3% to 57.8%, respectively, while flag leaf photosynthesis contributed less than 12.2%. The participation of ear (spike and awns) to grain filling was also high, but spike participated more than awns, particularly in photosynthesis. The participation of flag leaf (both through photosynthesis and re-mobilization) was lower than the participation of awns. The contribution of the spike was slightly increased in Season 2, compared to Season 1. The contribution of stem, although similar in both seasons in Caravaca Colorado, was much higher in Casablanca 7580 in Season 2 than in Season 1.
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Dynamics of light and nitrogen distribution during grain filling within wheat canopy

Dynamics of light and nitrogen distribution during grain filling within wheat canopy

grain-filling period? Does the time course of N mass per unit dry mass during grain filling follow a similar pattern in all vegetative organs? More specifically, does N depletion in the different vegetative organs follow unique first-order kinetics in the period of no apparent root N uptake? To investigate these ques- tions, we studied in the field two bread wheat culti- vars, Apache and Isengrain, from anthesis to grain maturity. To take into account local light environment and N translocation from individual organs to grains, N dynamics were characterized for both vertical can- opy layers and individual organs. We explicitly took into account the different vegetative organs (i.e. leaf laminae, leaf sheaths, internodes, and chaff). This study provides new insights into the mechanisms and driving variables governing N dynamics during the reproductive stage for wheat, both at the organ and whole plant levels. They provide the basis to construct a functional model at the whole plant level as well as for the integration of results at the molecular level into the context of whole plant physiology. Such an inte- grated knowledge would greatly enhance our chances of achieving genetic improvement in yield and crop N use efficiency.
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Improving grain filling and potential grain size

Improving grain filling and potential grain size

6 John Innes Centre, UK; 7 INRA France; 8 University of Lerida, Spain Optimizing the partitioning of assimilates to different plant organs to maximize HI There has been no systematic genetic progress in HI since the early 1990s ; from values of ca. 0.45-0.50 in spring wheat and ca. 0.50-0.55 in winter wheat (Hay 2008; Foulkes et al. 2009), but of greater concern is that expression of HI is not well controlled, neither in terms of breeding outcomes nor in terms of its expression across environments and years. In fact, large genetic ranges for dry matter (DM) partitioning are reporte d across all plant organs. In theory at least, by combining the lowest values of DM partitioning observed for each of the alternative sinks (stem, leaves etc), the relative spike mass at anthesis could be increased to 0.35, from the present maximum values of c. 0.30 in spring wheat, which we would expect to boost HI. However, potential trade-offs will need to be carefully assessed to avoid, for example, negative impacts on canopy photosynthetic capacity, root growth, and lodging resistance (Foulkes et al. 2011). In addition, the balance between structural stem and non-structural (soluble) stem carbohydrate must be optimized across environments, taking account of whether assimilate availability during grain filling – and therefore realization of grain weight potential – may be limited by high
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Trade-off between grain weight and grain number and key traits for increasing potential grain weight in CIMCOG population

Trade-off between grain weight and grain number and key traits for increasing potential grain weight in CIMCOG population

Overall these results indicated that new CIMMYT cultivars may have some extent of co-limitation of grain growth by source and sink. Similar results were found by Kruk et al. (1996) where modern spring cultivars were more sensitive to defoliation than the older cultivars, indicating a simultaneous limitation of grain growth by the sink and source. So for future gains in yield potential source traits which can be simultaneously increased with grain sink size may be a priority for plant breeding. In this respect, enhancing pre-anthesis RUE and stem WSC may offer some promise (Fischer & Edmeades, 2010; Reynolds et al. 2012). Lopes et al. (2012) reported that the stay green trait was associated with grain yield under heat and drought in different locations. In the present experiment, however, senescence rates were not associated with grain yield in the control treatment or grain yield responses to source-sink treatments. The source-sink balance according to the model of Bingham et al (2007) indicated that several of the genotype (line 19) were in close source-sink balance and one genotype (line 19) was sink limited. There was a strong trend for source-sink balance estimated by the model to show linear associations with the degree of sink limitation estimated by the source-sink manipulation treatments. The association between grain weight response to degraining and the source-sink balance from the model must be interpreted cautiously since the final grain weight in the degraining treatment was used in the model to estimate potential grain weight, so these two estimates for source- sink balance are not completely independent. However, it is encouraging that there was also a trend for a linear association between the source-sink balance estimated according to the model and the grain growth responses to defoliation. These results support the hypothesis that the degree of sink limitation differed in these nine spring wheat genotypes and that there was some evidence that grain growth of higher yields lines to be co-limited by source and sink. Other recent studies have also indicated that co-limitation of grain growth by source and sink could occur in modern wheat cultivars in Mediterranean wheat (Acreche and Slafer, 2009) and from a comparative survey under high yielding conditions (Sandana et al. 2009). Similarly in 39 modern wheats in Argentina, Gonzalez et al. (2014) found the response of grain weight to an increment of 100% in the source per grain during grain filling ranged from 0 to 25% depending on cultivar and year suggesting a source-sink co-limitation during grain filling in the most responsive cases. Overall these results suggested that modern CIMMYT cultivars may have a co-limitation of grain growth by source and sink.
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Design of computer experiments: space filling and beyond

Design of computer experiments: space filling and beyond

still (n!) d−1 /(d−1)! if we consider designs as equivalent when they differ by a permutation of coordinates. An exhaustive search is thus quickly prohibitive even for moderate values of n and d. Most algorithmic methods are of the exchange type, see Sect. 7. In order to re- main in the class of Lh designs, one exchange-step corre- sponds to swapping the j-th coordinates of two points, which gives (d − 1)n(n − 1)/2 possibilities at each step (the first coordinates being fixed). Another approach that takes projectional properties into account but is not restricted to the class of Lh designs will be pre- sented in Sect. 3.3. Note that originally McKay et al (1979) have introduced Lh designs as random sampling procedures rather than candidates for providing fixed designs, those random designs being not guaranteed to have good space-filling properties. Tang (1993) has in- troduced orthogonal-array-based Latin hypercubes to improve projections on higher dimensional subspaces, the space-filling properties of which were improved by Leary et al (2003). The usefulness of Lh designs in
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Filling Holes in Triangular Meshes by Curve Unfolding

Filling Holes in Triangular Meshes by Curve Unfolding

3 Massachusetts Institute of Technology, Massachusetts, USA Abstract—We propose a novel approach to auto- matically fill holes in triangulated models. Each hole is filled using a minimum energy surface that is obtained in three steps. First, we unfold the hole boundary onto a plane using energy minimization. Second, we triangulate the unfolded hole using a con- strained Delaunay triangulation. Third, we embed the triangular mesh as a minimum energy surface in R 3 . The running time of the method depends primarily on the size of the hole boundary and not on the size of the model, thereby making the method applicable to large models. Our experiments demonstrate the applicability of the algorithm to the problem of filling holes bounded by highly curved boundaries in large models.
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Bayesian quadrature, energy minimization and space-filling design

Bayesian quadrature, energy minimization and space-filling design

BAYESIAN QUADRATURE, ENERGY MINIMIZATION AND SPACE-FILLING DESIGN LUC PRONZATO † AND ANATOLY ZHIGLJAVSKY ∗ Abstract. A standard objective in computer experiments is to approximate the behavior of an unknown function on a compact domain from a few evaluations inside the domain. When little is known about the function, space-lling design is advisable: typically, points of evaluation spread out across the available space are obtained by minimizing a geometrical (for instance, covering radius) or a discrepancy criterion measuring distance to uniformity. The paper investigates connections between design for integration (quadrature design), construction of the (continuous) BLUE for the location model, space-lling design, and minimization of energy (kernel discrepancy) for signed mea- sures. Integrally strictly positive denite kernels dene strictly convex energy functionals, with an equivalence between the notions of potential and directional derivative, showing the strong relation between discrepancy minimization and more traditional design of optimal experiments. In particular, kernel herding algorithms, which are special instances of vertex-direction methods used in optimal design, can be applied to the construction of point sequences with suitable space-lling properties.
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Prior and macro-filling order for image completion

Prior and macro-filling order for image completion

This paper introduces an algorithm to build priors that help image completion to produce better and visually plausible results. The goal of the prior is to seamlessly reconstruct long edges, that exemplar- based inpainting fails to restore. The prior consists in locating the edges across the missing region, and separating the image in regions of relative similar textures. Unlike other techniques, our proposal does not use segmentation or inpainting to obtain the prior, provid- ing a fast technique. Moreover, the technique does not rely on image dependent threshold. Finally, we propose a scheduling for the syn- thesis of the missing region based on the prior, and Criminisi’s algo- rithm. The scheduling may be thought as a novel macro-filling order for exemplar-based synthesis. The results are comparable with re- cent and more complex proposals based on super-resolution or Pho- toshop. Finally, we emphasize that, our prior is not dedicated to our image completion algorithm, and can be used to drive other image completion or inpainting algorithms.
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Création d'une interface graphique pour le gap filling de données météorologiques

Création d'une interface graphique pour le gap filling de données météorologiques

Malheureusement, ces données météo contiennent des valeurs manquantes (gap). Ces données sont toutefois essentielles pour le modèle de simulation et celui-ci n’accepte pas de série de données incomplètes. L’objectif du Gap Filling, comme son nom l’indique, est de compléter artificiellement ces données de la manière la plus correcte possible. Pour arriver à cela, deux étudiants en troisième année à l’ISIMA ont étudié et implémenté des méthodes mathématiques de remplissages existantes et en ont créé de nouvelles en s’appuyant sur leurs connaissances et leurs recherches.
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Tracking stressed blood volume during vascular filling experiments

Tracking stressed blood volume during vascular filling experiments

4. CONCLUSION SBV is identified using a simple cardiovascular system model, whose parameters are adjusted to fit data from vascular filling experiments in pigs. SBV seems to be a good predictor of the change in CO after fluid infusion. More experiments are currently being performed to further investigate the effects of vascular filling. References

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Mold Filling Simulation of Semi-Solid Magnesium Alloys

Mold Filling Simulation of Semi-Solid Magnesium Alloys

Mold Filling Simulation of Semi-Solid Magnesium Alloys Ilinca, Florin; Hétu, Jean-Francois; Ajersch, Frank; Moisan, Jean-Francois https://publications-cnrc.canada.ca/fra/droits L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB.

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A machine learning filter for the slot filling task

A machine learning filter for the slot filling task

Keywords: information retrieval; information extraction; relation extraction; slot filling; knowledge base population; most frequent patterns; precision; data mining 1. Introduction In the age of structured knowledge bases such as Google Knowledge Graph [ 1 ], DBpedia [ 2 ] and the Linked Open Data cloud [ 3 ], relation extraction is becoming a very important challenge for enhanced semantic search. Relation extraction and its sub-task, slot filling, have been very active in recent years and have been subject to several evaluation campaigns that assess the ability of automatically extracting previously known relations from corpora. Despite some progress, the results of these competitions remain limited. Relation extraction generally consists of extracting relations from unstructured information. This is done by identifying the meaningful links between named entities. Slot filling goes one step further by providing a template defining the relations for which a named entity needs to be linked. In this paper, we focus on the Text Analysis Conference (TAC) Knowledge Base Population (KBP) English Slot Filling (ESF) track, which is an evaluation campaign that targets the extraction of 41 pre-identified Wikipedia info-box relations (e.g., title, date of birth, countries of residence, etc.) related to specific named entities (persons and organizations) [ 4 ]. In this task, a named entity (the query entity) and a relation (the slot) are submitted to the system, which must find every other entity (the filler) that is linked to this entity with this particular relation, and must return a textual segment that justifies this result [ 4 , 5 ]. The goal of this task is to populate a reference knowledge base,
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Du grain au pain : les outils de 1ère transformation

Du grain au pain : les outils de 1ère transformation

• Exemple d’un projet en France de meunerie + atelier pain :. – Vente du blé panifiable 0,40 €/kg – Vente farine entre 0,80 et 1,20 €/kg – Vente pain 4 €/kg[r]

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Misorientation dependence grain boundary complexions in <111> symmetric tilt Al grain boundaries

Misorientation dependence grain boundary complexions in <111> symmetric tilt Al grain boundaries

Herein, we report the atomic-level structure of Cu segregation induced GB complexions at the various GBs (LAGBs, special GBs, and random HAGBs) of Al 7075 alloy showing distinct types of segregation behavior. Firstly, the important structural features such as grain size, texture, and boundary type and connectivity distri- bution into the films were examined by using automated crystal orientation mapping assisted with precession electron diffraction. Following the results, the atomic scale adsorbate arrangement patterns across the GBs were revealed through aberration- corrected scanning transmission electron microscopy (STEM) im- aging. Structural model of the grain boundaries is proposed as well as the segregation behavior was energetically studied by atomistic simulations. Detailed spectroscopy analyses (energy dispersive X- ray spectroscopy (EDS) and electron energy loss spectroscopy (EELS)) were performed to identify the chemical nature of segre- gating element.
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Beyond Adjacency Maximization: Scaffold Filling for New String Distances

Beyond Adjacency Maximization: Scaffold Filling for New String Distances

Abstract In Genomic Scaffold Filling, one aims at polishing in silico a draft genome, called scaffold. The scaffold is given in the form of an ordered set of gene sequences, called contigs. This is done by confronting the scaffold to an already complete reference genome from a close species. More precisely, given a scaffold S, a reference genome G and a score function f () between two genomes, the aim is to complete S by adding the missing genes from G so that the obtained complete genome S ∗ optimizes f (S ∗ , G). In this paper, we extend a model of Jiang et al. [CPM 2016]

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Investigating host-microbiota cooperation with gap-filling optimization problems

Investigating host-microbiota cooperation with gap-filling optimization problems

More generally, fluxes can help choosing between all minimal communities of bacteria se- lected by Miscoto. They could be integrated in the process of community selection as another short term objective related to optimization. Relying on hybrid activation could therefore be considered. This thesis has demonstrated the interest of graph-based semantics in a field that is still strongly dominated by the constraint-based one. I believe that combining both is of high interest and in that sense, hybrid semantics can be applied to many problems apart from gap-filling which has been done in this thesis. For instance, the selection of community and more generally the analysis of microbiota could be extended to support the hybrid seman- tics. So far, the prediction of communities with Miscoto implies the graph-based semantics of metabolic activation. We are aware the absence of constraint-based semantics can be seen as a major limitation and we advocated that flux-based modeling of the communities can be done after the selection we provide, to filtrate the solutions. We can imagine the application of hybrid graph-based/constraint-based semantics to the community selection problem, as both have been individually applied to the study of microbiota [Julien-Laferrière et al., 2016, Frioux et al., 2018a, Opatovsky et al., 2018, Eng and Borenstein, 2016, Zomorrodi et al., 2014]. In par- ticular, flux constraints could be applied to the putative transports that would ensure the exchanges predicted by Miscoto are feasible. Indeed, since several sets of minimal exchanges often co-exist for a minimal community, decision between them could be contemplated with fl uxes by testing their distribution into the exchange reactions selected by Miscoto.
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Gap Filling of 3-D Microvascular Networks by Tensor Voting

Gap Filling of 3-D Microvascular Networks by Tensor Voting

by the active contours [11]. The evolution equation is modi- fied by adding a force which makes neighboring regions attract one another. Bicego et al. [12] look for parallel straight lines in small subimages of streets using a Hough transform. The re- sulting small segments are then used to initialize a contour fol- lowing algorithm, which starts in a direction perpendicular to the image gradient. In [13], road network midlines are first ex- tracted. The midline endpoints are thus easily detected. They be- come the seeds of the gap filling algorithm. The nearby seeds are then compared with one another through a cost function and are merged. In [14], Lacoste et al. apply a global optimization so- lution with simulated annealing for gap filling in line networks. The cost function depends on the configuration of the overall line endpoint pairs.
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