Adaptive Function and Brain Evolution

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The response of wheat genotypes to inoculation with Azospirillum brasilense

It is well documented in many studies that plant growth promoting rhizobacteria (PGPR) are capable of increasing plant growth and productivity in a range of agricultural crops, reducing dependence on chemical amendments and maintaining a safe environment. Over the last two decades PGPR inoculants have been increasingly used in agriculture to improve crop productivity and farming system sustainability. Such eco-friendly technologies are needed to address sustainable food security and to avoid global dependence on hazardous agricultural chemicals which ultimately destabilize agro-ecosystems. The nitrogen fixing bacteria, Azospirillum brasilense, has been an important PGPB (plant growth promoting bacteria) used to enhance the growth and yield of many crops globally. This is attributed mainly to its ability to produce phytohormones. While much is known about A. brasilense, the promising effect of PGPBs in general in the field is limited by factors that influence their survival and activity in the rhizosphere. The attachment of bacteria to roots is an essential and necessary condition for the establishment of an effective association. This association is dependent upon the population density of active PGPB cells in the rhizosphere which are able to compete with indigenous bacteria. However, how survival and persistence of inoculant bacteria in the rhizosphere, the effect of inoculum on the rhizosphere community, in particular the nitrogen fixing community, and the effect of plant genotype contributes to plant growth promotion by Azospirillum in the field have not been widely studied. Better understanding of the plant x inoculum interaction requires determining if there is an effect of plant genotype and monitoring and estimation of the persistence of PGPB in the rhizosphere. The overall aim of this project was to examine the effect of the wheat (Triticum aestivum) genotype x Azospirillum interaction on colonization of roots and plant growth promotion. These effects were studied under both controlled hydroponic conditions in the laboratory and in the field. Plant growth parameters and bacterial colonization of the rhizosphere were determined in both conditions. Differences in root characteristics of twenty three diverse wheat genotypes were observed after growth in the hydroponic system; however responses to inoculation with A. brasilense Sp7 and Sp7-S were variable. In some cases growth parameters were increased and in others they were decreased. There was an apparent increase in responsiveness to inoculation with azospirilla by synthetically derived genotypes observed in root length measurements but otherwise there was no trend according to the genetic source of wheat. Microscopic observations confirmed the different root colonisation patterns by Sp7 and Sp7-S. However, colonisation pattern was not influenced by plant genotype. Relationships between shoot dry weight and root growth parameters were positive as expected but were strengthened with inoculation

Auto-combustion synthesis of perovskite-type oxides SrTi1−xFexO3−δ

A versatile one-pot auto-combustion method for the synthesis of powders of iron-doped strontium titanate, SrTi1−xFexO3−δ, has been developed. The synthesis is optimized by the combined use of EDTA and citric acid as chelating agents, and an appropriate balance between fuel and oxidizing elements in the reaction mixture. The method produces immediately an almost phase-pure perovskite oxide powder, with an ultra-fine crystallite size of 20–40 nm, and with a low level of organic residues. Highly sinter-active powders are obtained after calcination and ball-milling of the powders

The representation of white matter in the central nervous system

The white matter of the central nervous system (CNS) is difficult to represent in anatomy because it is located predominantly “between” other anatomical entities. In a classic presentation, like a cross section of a brain segment, white matter is present and can be labeled adequately. Several appearances of the same entity are feasible on successive cross section views. The problem is the absence of a global view on long tracts, and more generally, the lack of a comprehensive classification of white matter pathways. Following the recent revision of the Terminologia Anatomica (TA, 1998), in particular the chapter on the nervous system, resulting in the Terminologia Neuroanatomica (TNA, 2017), the authors have developed a new schema for the representation of white matter. In this approach, white matter is directly attached to the CNS, and no longer considered as part of the brain segments. Such a move does not affect the content but redistributes the anatomical entities in a more natural fashion. This paper gives an overall description of this new schema of representation and emphasizes its benefits. The new classification of white matter tracts is developed, selecting the origin as the primary criterion and the type of tract as the secondary criterion

The Representation of White Matter in the Central Nervous System

The white matter of the central nervous system (CNS) is difficult to represent in anatomy because it is located predominantly “between” other anatomical entities. In a classic presentation, like a cross section of a brain segment, white matter is present and can be labeled adequately. Several appearances of the same entity are feasible on successive cross section views. The problem is the absence of a global view on long tracts, and more generally, the lack of a comprehensive classification of white matter pathways. Following the recent revision of the Terminologia Anatomica (TA, 1998), in particular the chapter on the nervous system, resulting in the Terminologia Neuroanatomica (TNA, 2017), the authors have developed a new schema for the representation of white matter. In this approach, white matter is directly attached to the CNS, and no longer considered as part of the brain segments. Such a move does not affect the content but redistributes the anatomical entities in a more natural fashion. This paper gives an overall description of this new schema of representation and emphasizes its benefits. The new classification of white matter tracts is developed, selecting the origin as the primary criterion and the type of tract as the secondary criterion