Добірка наукової літератури з теми "Kernel morphometry"

Wheat is one of the most important crops in the world, providing food for most of the world’s population. Wheat seeds are a popular model object for many experiments to evaluate various factors that improve germination or protect against various adverse stressful effects. Based on the high significance of increasing the productivity of this cereal crop and the applicability of this object, a detailed statistical evaluation of wheat grain (kernel) morphometry was carried out to assess the asymmetry of parameters of this ideal model. Depending on the location of the kernels in the spikelet of a wheat spike, there was a significant asymmetry between the right and left cheeks of the kernels located closer or further from the center of the spikelet. The expressiveness of asymmetry, and consequently, the kernel deformation was higher in the lower kernels of the spikelet. The degree of symmetry; that is, the similarity of the two halves (cheeks) and the kernel as a whole, was higher in kernels located higher in the spikelet. It seems that the reason for this phenomenon lies in the mechanical nature of kernel deformation. The ultrastructure of A-type and B-type starch grains in the central part of the kernel had significant differences between the upper and lower kernels, which indicated in favor of a high probability of differences by the composition and quality of kernels of the same variety when assessed separately. Uniform development of kernels and smaller differences between them may reveal more valuable genotypes in the future, provided their steady reproduction under adverse conditions of a changing climate.

This study aimed to analyze the influence of inoculation methods with Azospirillum brasilense in morphometric and nutritional parameters of the maize crop. Maize plants, hybrid Formula VT®, were grown under different forms of inoculation: absence of inoculation; seed inoculation; leaf inoculation; seed inoculation associated to leaf inoculation. In the phenological stages V8 and VT the parameters number of leaves, aerial height, root volume, stem diameter, besides the leaves, stem, sheath, root and total dry mass and the leaf content of nitrogen, phosphorus and potassium were determined. In the R6 stage, in addition to the previous evaluations the following parameters were determined: ear diameter and length, number of kernel rows, number of kernels per row, the reproductive structure and thousand grains dry mass, and total number of grains, besides the grain’s content of nitrogen, phosphorus, and potassium. The SPAD index from the leave’s apex, medial and basal thirds was measured fortnightly. The inoculation methods with A. brasilense had little influence in maize’s morphometric and nutritional parameters, also not influencing in production. Maize plants inoculated with A. brasilense, via seed and via seed associated to leaf spraying, positively stood out for the stem diameter, leaves dry mas, root volume, and for the nitrogen, phosphorus, and potassium leaf content.

Voxel-based morphometry provides an opportunity to study Alzheimer’s disease (AD) at a subtle level. Therefore, identifying the important brain voxels that can classify AD, early mild cognitive impairment (EMCI) and healthy control (HC) and studying the role of these voxels in AD will be crucial to improve our understanding of the neurobiological mechanism of AD. Combining magnetic resonance imaging (MRI) imaging and gene information, we proposed a novel feature construction method and a novel genetic multi-kernel support vector machine (SVM) method to mine important features for AD detection. Specifically, to amplify the differences among AD, EMCI and HC groups, we used the eigenvalues of the top 24 Single Nucleotide Polymorphisms (SNPs) in a p-value matrix of 24 genes associated with AD for feature construction. Furthermore, a genetic multi-kernel SVM was established with the resulting features. The genetic algorithm was used to detect the optimal weights of 3 kernels and the multi-kernel SVM was used after training to explore the significant features. By analyzing the significance of the features, we identified some brain regions affected by AD, such as the right superior frontal gyrus, right inferior temporal gyrus and right superior temporal gyrus. The findings proved the good performance and generalization of the proposed model. Particularly, significant susceptibility genes associated with AD were identified, such as CSMD1, RBFOX1, PTPRD, CDH13 and WWOX. Some significant pathways were further explored, such as the calcium signaling pathway (corrected p-value = 1.35 × 10−6) and cell adhesion molecules (corrected p-value = 5.44 × 10−4). The findings offer new candidate abnormal brain features and demonstrate the contribution of these features to AD.

Abstract The NASA Dawn mission revealed that the floor of Occator crater on the dwarf planet Ceres (in the main asteroid belt between Mars and Jupiter) is populated with small quasi-conical hills. Many of these features exhibit morphometric properties that are like those of ice-cored periglacial hills called pingos. Alternatively, some of these Cerean hills have also been hypothesized to be cryovolcanic in origin. If these hills are analogous to pingos, they represent ice-rich environments that are attractive targets for future exploration. We report new constraints on the morphologies of the Occator hills that aid in determining their origin. We also directly test how morphologically similar the hills in Occator are to pingos and volcanic cones on Earth using comparative statistical analyses. Using a novel application of kernel density estimation and Markov chain Monte Carlo methods we show that the morphologies of terrestrial pingos and volcanic cones are quantifiably distinct, and that the Cerean hills share significant morphometric similarities with pingos on Earth. Our findings indicate that a statistical treatment of morphometry alone can be a powerful tool for classifying and comparing planetary surface features, and that the majority of the resolved Cerean hills are morphometrically more similar to pingos than to small terrestrial volcanic cones.

Accurate classification of maturity status and estimation of size at 50% maturity for male crabs are important to the management of North Pacific crab stocks, which form the basis of several economically valuable fisheries. We demonstrate a straightforward maturity classification approach applied to male Tanner crabs ( Chionoecetes bairdi), based on the use of log-transformed chela height distributions calculated via kernel density functions. The linear equation defining the relationship between the minima of these chela height distributions, and the midpoint of the corresponding carapace width bins is then used to estimate the incidence of maturity by size group across the population. We demonstrate the performance of this approach relative to two other currently applied methodologies. Finally, we apply this method to assess annual size at 50% maturity in eastern Bering Sea male Tanner crabs, and spatiotemporal trends in this parameter. We demonstrate the existence of high interannual and spatial variability in this population metric and find evidence of a decline in size at maturity in the western stock.

The present investigationon evaluation of provenance variations in seed morphometric, germination and seedling growth attributes of Neem was conducted at Division of Genetics and Tree Improvement at Institute of Forest Genetics and Tree Breeding, Coimbatore, Tamil Nadu, India with an aim to study the variation in different provenances of Azadirachta indicafor seed morphometry, germination and seedling traits,to identify superior provenances of Azadirachta indica to produce quality planting stocks, during monsoon of 2021 and 2022. Extensive surveys were conducted in 6 different agro-climatic zones in Tamil Nadu and selected 30 Candidate Plus Trees (CPT’s) based on growth superiority and higher fruit yield. The significant differences were recorded on seed length (cm), seed width (cm), seed perimeter (cm), seed area, and 100 seed kernel weight (g), germination percentage, mean daily germination, germination value, germination time, peak value, time spread of germination and germination index and seedling characters such as shoot length, root length, color diameter, leaf numbers, shoot fresh weight, root fresh weight, shoot dry weight, root dry weight, shoot and root vigorous index among the provenances and seed lots. Southern Zone and Rainfall Zone provenances recorded higher values on seed length and breadth, seed weight and seedling parameters and lower values of seed parameters were observed in the Western Zone and seedling parameters in North Eastern Zone. Seed length, seed area, seed perimeter and germination percentage had a significant strong positive correlation with the shoot vigour index. Southern Zone and Rainfall Zone provenances can be recommended for establishing large-scale plantation in the Tree Outside Forest (ToF).

Global climate change provide the emergence of new opportunities for the introduction of new crops into horticultural production in the areas of insufficient precipitation. In addition to the economic aspect, it is also of interest to the biologists of the development of this plant in a qualitatively new environment.The paper considers the variability of the main traits of plant morphometry, yield for four varieties of hazelnuts in order to identify the most promising forms for cultivating in the northern part of the Steppe of Ukraine characterized by an insufficient precipitation and harsh winters. Recent milder winter conditions and a certain balance in summer droughts have made the required horticultural production possible, thereby increasing the production of hazelnuts and addressing the dietary problems of people in terms of supply of necessary vitamins and micronutrient element from hazelnuts. Promising varieties for the production plantations have been specified, the mechanisms for the yield formation have been studied. Key traits of morphometry have been identified that condition the success of a variety under insufficient humidity. These were such traits as crown volume, leaf surface area, shell thickness, average weight of one nut, weight of dry nuts, yield, kernel yield. It has been established that the yield formation on account of large, well-shaped nuts is best in terms of yield. Some aspects of yield formation and the possibility of combining different varieties, especially when more intensive growing methods are applied, are of additional interest. High variability significantly prevents the modeling of traits, for example, such as yield per tree, from being significant in terms of the formation of high yield. Semi-intensive pruning of hazelnut bushes shows its suitability for use in modern garden plantings. Variety Barselonskiy showed extremely high variability for many key parameters, which may indicate insufficient stability of this variety from a genetic point of view and the presence of a fairly significant number of hidden biotypes, which is additionally negative for cultivation in modern semi-intensive and intensive technologies. Climate change makes it possible to continue to significantly expand the area under hazelnuts due to the previously considered unfavourable southern subzones of the Forest-Steppe and the Steppe zone of Ukraine. Such new and previously unnoticed effects have been noted as fruiting in the first year in production crops, the formation of up to 5–6 inflorescences for each nut-bearing branch in the second or third year. For further investigations, it is planned to analyze the nutritional qualities of the obtained products, in terms of the composition by microelements and the presence of biologically-active substances, to trace the dynamics of the accumulation of heavy metals and the potentially associated risks.

L’apprentissage inter-sujet consiste à fournir des prédictions sur des données d'un sujet humain non présent dans la base d’apprentissage, comme dans l’aide au diagnostic où un ordinateur doit prédire si un sujet inconnu est sain ou malade. Dans cette thèse, nous défendons le point de vue que ce problème doit être formalisé dans le cadre multi-source, où chaque sujet d’apprentissage fournit une source de données. Nous présentons ensuite trois contributions destinées à des applications en neuroimagerie.La première est une méthode de prédiction inter-sujet pour données d'IRM fonctionnelle. La variabilité inter-sujet fait que les espaces d’entrée sont tous différents. Nous construisons un espace commun à l'aide de graphes et d'un noyau de graphe, qui projette ces données dans un espace de hilbert à noyau reproduisant. Nous démontrons l’efficacité de cette approche sur des données de tonotopie enregistrées dans le cortex auditif.La deuxième est une méthode de morphométrie corticale. Nous construisons des graphes à partir des extrema de profondeur du cortex, que nous projetons dans un espace commun grâce à un noyau de graphe. Une méthode d’inférence spatiale permet l’identification des zones du cortex qui présentent des différences entre populations. Nous étudions avec cette méthode les asymétries corticales et les différences inter-sexe.La troisième est une méthode d’adaptation de domaine multi-source. Nous décrivons une extension du kernel mean matching au cas où l’ensemble d’apprentissage se compose de plusieurs sources de données et des résultats préliminaires sur une tâche de classification inter-sujet dans une expérience de magnéto-encéphalographie
Inter-subject learning consists in giving predictions on data from a subject not present in the training database, as with computer-aided diagnosis where the computer has to guess wether an unknown individual is healthy or sick. In this thesis, we argue that inter-subject learning should be handled in the multi-source framework where each subject is a different source of data. We then introduce three original contributions for neuroimaging applications.The first one is a method for inter-subject predictions of fMRI data. Because of the inter-subject variability, the original feature spaces are all different. Using graphs and a graph kernel, the input patterns are implicitly projected into a common reproducing kernel hilbert space. We show the effectiveness of this method on tonotopy data recorded in the auditory cortex.The second one is a cortical morphometry method. We design graphs from the deepest points of cortical sulci, and we project them into a common space using a graph kernel. A spatial inference method is then proposed to perform the detection of cortical zones where populations are different. Using this method, we study cortical asymmetries and gender differences.The third contribution of this thesis is a multi-source domain adaptation technique. Our method is an extension of the kernel mean matching for the multi-source case. We present preliminary results on a inter-subject prediction task used to analyse data from a magneto-encephalography experiment

Dans un contexte de crise socio-écologique remettant en question la capacité du système agricole industriel à garantir la sécurité alimentaire et une alimentation de qualité, l’agroécologie émerge comme une alternative de plus en plus crédible. Un des majeurs fondements réside dans la réintroduction de biodiversité cultivée dans les systèmes agro-alimentaires. Cette thèse s’intéresse à trois espèces de blés marginales, appelées « blés vêtus » : l’engrain, l’amidonnier et le grand épeautre. Elle vise à évaluer leur viabilité agronomique, ainsi que leur qualité nutritionnelle, en particulier la composition en protéines du gluten. Située en région lyonnaise, cette recherche adopte une approche participative. Elle répond ainsi à deux autres principes de l’agroécologie : la relocalisation des systèmes alimentaires et le décloisonnement de la recherche en dehors de la sphère académique. Au cours de la thèse, nous avons évalué 23 variétés de blés vêtus en comparaison à huit variétés de blé tendre, en collaboration avec un centre de ressources botaniques, une association paysanne et six paysan.ne.s. Il en résulte que l’engrain se distingue des trois autres espèces sur le plan agronomique et sur la composition du gluten. Cette espèce est notamment caractérisée par un potentiel de tallage et une teneur en protéines élevées, et par de faibles proportions de gluténines. L’étude révèle également une forte variabilité intra-spécifique, en particulier pour les variétés d’amidonnier, soulignant l’intérêt de ces espèces comme sources de diversité. Enfin, l’évaluation réalisée au cours de la thèse a permis d’identifier des variétés présentant des caractéristiques notables, tant au niveau agronomique que concernant la composition des protéines du gluten. Au-delà des résultats d’évaluation des variétés, cette thèse propose une analyse réflexive du processus de recherche participatif. Elle identifie les forces et les limites de l’approche menée, et suggère des pistes d’amélioration. En conclusion, cette thèse pose les bases pour la poursuite du projet d’évaluation des blés vêtus, tant du point de vue de la méthodologie d’évaluation que de l’approche participative
Amidst a backdrop of socio-ecological crisis that raises questions about the capacity of industrial agriculture to ensure food security and quality food, agroecology has emerged as an increasingly credible alternative. A pivotal aspect of agroecology is the reintroduction of cultivated biodiversity into agri-food systems. This thesis focuses on three marginal wheat species, known as "hulled wheats" : einkorn, emmer, and spelt. It aims to assess their agronomic viability, as well as their nutritional quality, with a specific focus on the composition of gluten proteins. Situated in the Lyon region, this research embraces a participatory approach, aligning with two core principles of agroecology : the relocalization of food systems and the breaking down of barriers between research and the wider community. During this thesis, we evaluated 23 hulled wheat varieties, in comparison with eight common wheat varieties. This work was done in collaboration with a botanical resource center, a farmers’ association, and six farmers. The results show that einkorn clearly differs from the other three species, in terms of agronomic features and gluten composition. In particular, einkorn is characterized by an elevated tillering potential, a high protein content, and a notably low proportion of glutenins. The study also revealed high levels of intra-specific variability, particularly within the set of emmer varieties, which highlights the value of these species as a source of diversity. Finally, the evaluation undertaken during this thesis enabled us to identify varieties with noteworthy characteristics, either agronomically or in relation to gluten protein composition. Beyond the results of the variety evaluation, this thesis provides a reflective analysis of the participatory research process, identifying its strengths and limitations, and presenting recommendations for its improvement. In conclusion, this thesis lays the groundwork for the continuation of the hulled wheat evaluation project, encompassing both the evaluation methodology and the participatory approach