19 research outputs found

    Classical Morphology of Plants as an Elementary Instance of Classical Invariant Theory

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    It has long been known that structural chemistry shows an intriguing correspondence with Classical Invariant Theory (CIT). Under this view, an algebraic binary form of the degree n corresponds to a chemical atom with valence n and each physical molecule or ion has an invariant-theoretic counterpart. This theory was developed using the Aronhold symbolical approach and the symbolical processes of convolution/transvection in CIT was characterized as a potential “accurate morphological method”. However, CIT has not been applied to the formal morphology of living organisms. Based on the morphological interpretation of binary form, as well as the process of convolution/transvection, the First and Second Fundamental Theorems of CIT and the Nullforms of CIT, we show how CIT can be applied to the structure of plants, especially when conceptualized as a series of plant metamers (phytomers). We also show that the weight of the covariant/invariant that describes a morphological structure is a criterion of simplicity and, therefore, we argue that this allows us to formulate a parsimonious method of formal morphology. We demonstrate that the “theory of axilar bud” is the simplest treatment of the grass seedling/embryo. Our interpretations also represent Troll's bauplan of the angiosperms, the principle of variable proportions, morphological misfits, the basic types of stem segmentation, and Goethe's principle of metamorphosis in terms of CIT. Binary forms of different degrees might describe any repeated module of plant organisms. As bacteria, invertebrates, and higher vertebrates are all generally shared a metameric morphology, wider implications of the proposed symmetry between CIT and formal morphology of plants are apparent

    Weimar in America:Central European Émigrés, Classical Realism, or How to Prevent History from Repeating Itself

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    Many classical realists came from a diverse range of intellectual backgrounds, were often originally from Central Europe, and only turned their academic interests to International Relations once they had crossed the Atlantic. This includes scholars, who had left already before fascists were elected into governments across Europe, but most were forced into emigration after the Nazis came to power in Germany in 1933 because of their religious beliefs and/or political standpoints. This chapter reflects on the specific role Europe played in the development of their realist international political thought by investigating the influence of their forced migration, the Holocaust, and the rise of totalitarianism, while not forgetting the role American interlocutors played in formulating their thought

    Morphological and architectural development of root systems in sorghum and maize

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    Root systems determine the capacity of a plant to access soil water and their architecture can influence adaptation to water-limited conditions. It may be possible to associate that architecture with root attributes of young plants as a basis for rapid phenotypic screening. This requires improved understanding of root system development. This study aimed to characterise the morphological and architectural development of sorghum and maize root systems by (i) clarifying the initiation and origin of roots at germination, and (ii) monitoring and quantifying the development of root systems in young plants. Three experiments were conducted with two maize and four sorghum hybrids. Sorghum produced a sole seminal (primary) root and coleoptile nodal roots emerged at the 4th–5th leaf stage, whereas maize produced 3–7 seminal (primary and scutellum) roots and coleoptile nodal roots emerged at the 2nd leaf stage. Genotypic variation in the flush angle and mean diameter of nodal roots was observed and could be considered a suitable target for large scale screening for root architecture in breeding populations. Because of the relatively late appearance of nodal roots in sorghum, such screening would require a small chamber system to grow plants until at least 6 leaves had fully expanded. © 2010 Springer Science+Business Media B.V
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