Nitrogen dynamics in a mature Miscanthus x giganteus crop fertilized with nitrogen over a five year period

peer-reviewedThe objective of this study was to investigate N dynamics and response to N fertilization in a mature crop of Miscanthus x giganteus. A crop of Miscanthus x giganteus sown in 1994 was fertilized with five N rates (0, 38, 63, 90 and 125 kg N/ha/year) over a five year period (2008–2012) in Carlow, Ireland. Foliar chlorophyll concentrations were directly related to N fertilization level throughout the study and rose after N applications until July before falling with the onset of N remobilisation. Shoot numbers were unaffected by N fertilization until the final years of the study when they increased with N level. Crop height was unaffected by fertilization in the early years of the study but in the final years of the study, it increased with N level until July after which the effect diminished. There was a small but significant stimulation of harvested biomass yields in autumn (average 15 t/ha) with increasing N fertilization, but there was no effect on harvested yields in spring (average 10.5 t/ha). The N concentration in the rhizome network gradually built up during the course of the study and was proportional to N application. Aboveground biomass N content was also proportional to N application. Nitrogen remobilisation between the October and February harvests was small; abscissed leaves accounted for most of the N loss over this period. The deleterious environmental consequences of N fertilizer may outweigh any potential economic benefits if increases in biomass production are small or non-existent

From smart and corporate to urban and edgy: revitalising organisations in turbulent environments

Purpose: This paper aims to address issues surrounding the revitalising of organisations in turbulent environments. Design/methodology/approach: The paper contains a discussion of relevant issues and presentation of research which considers how leaders today are choosing to function in a very uncertain environment, that of higher education. Findings: The characteristics of urban and edgy organisations were all found to be evident in the leaders style in higher education. However, it was identified that this type of leadership rests on two critical axis–Knowledge management (shared and open) and the overarching style of leadership (empowerment and encouragement). Research limitations/implications: This work is introductory and used a small sample as a pilot–further more extensive work is needed in this area. Practical implications: This paper has introduced the idea of a new label for organisations which find themselves to be so full of diversity and differences that they can be characterised as being “on the edge” of danger–yet these organisations have found a way to be something which is separate from that of the urban character–important, flexible, dynamic, and playing a central role in development of new ideas. Originality/value: The contribution made to the discipline of leadership is the introduction of a new way of looking at organisation–the work offers new ways of looking at established ideas, through new lenses which may assist leaders and all who work in large organisations

A colored operad for string link infection

Budney recently constructed an operad that encodes splicing of knots. He further showed that the space of (long) knots is generated over this operad by the space of torus knots and hyperbolic knots, thus generalizing the satellite decomposition of knots from isotopy classes to the level of the space of knots. Infection by string links is a generalization of splicing from knots to links. We construct a colored operad that encodes string link infection. We prove that a certain subspace of the space of 2-component string links is generated over a suboperad of our operad by its subspace of prime links. This generalizes a result from joint work with Blair from isotopy classes of knots to the space of knots. Furthermore, all the relations in the monoid of 2-string links (as determined in our joint work with Blair) are captured by our infection operad.Comment: Some changes and corrections, mostly suggested by the referee. 38 pages, 14 figures. To appear in Algebr. & Geom. Topo

Localised states in an extended Swift-Hohenberg equation

Recent work on the behaviour of localised states in pattern forming partial differential equations has focused on the traditional model Swift-Hohenberg equation which, as a result of its simplicity, has additional structure --- it is variational in time and conservative in space. In this paper we investigate an extended Swift-Hohenberg equation in which non-variational and non-conservative effects play a key role. Our work concentrates on aspects of this much more complicated problem. Firstly we carry out the normal form analysis of the initial pattern forming instability that leads to small-amplitude localised states. Next we examine the bifurcation structure of the large-amplitude localised states. Finally we investigate the temporal stability of one-peak localised states. Throughout, we compare the localised states in the extended Swift-Hohenberg equation with the analogous solutions to the usual Swift-Hohenberg equation

The Silent Epidemic: Perspectives of High School Dropouts

Presents findings from a survey that examines why some students do not complete their high school education, and what academic and personal supports would have helped them stay in school. Includes recommendations for improving graduation rates

Snakes and ladders: localized solutions of plane Couette flow

We demonstrate the existence of a large number of exact solutions of plane Couette flow, which share the topology of known periodic solutions but are localized in space. Solutions of different size are organized in a snakes-and-ladders structure strikingly similar to that observed for simpler pattern-forming PDE systems. These new solutions are a step towards extending the dynamical systems view of transitional turbulence to spatially extended flows.Comment: submitted to Physics Review Letter

Evolution in cluster cores since z~1

A large fraction of the stellar mass in galaxy clusters is thought to be contained in the diffuse low surface brightness intracluster light (ICL). Being bound to the gravitational potential of the cluster rather than any individual galaxy, the ICL contains much information about the evolution of its host cluster and the interactions between the galaxies within. However due its low surface brightness it is notoriously difficult to study. We present the first detection and measurement of the flux contained in the ICL at z~1. We find that the fraction of the total cluster light contained in the ICL may have increased by factors of 2-4 since z~1, in contrast to recent findings for the lack of mass and scale size evolution found for brightest cluster galaxies. Our results suggest that late time buildup in cluster cores may occur more through stripping than merging and we discuss the implications of our results for hierarchical simulations.Comment: To appear in the Proceedings of IAU Symposium 295 - The intriguing life of massive galaxie

THE REUNIFICATION OF CRIMEA AND THE CITY OF SEVASTOPOL WITH THE RUSSIAN FEDERATION

Crimea and the City of Sevastopol justifiably separated from Ukraine and reunified with the Russian Federation in 2014. Support for this proposition is found in historic, economic, and political reasoning. Extant principles of public international law, derived from the Treaty of Westphalia, and subsequently developed by Great Powers to facilitate their strategic interests, when applied to the Crimean/Russian reunification, produce absurd results: nailing a population to a cross of misery, oppression, and poverty. In addition, the principles invoked are underdeveloped, prejudiced toward Nation States holding the imprimatur of “Great Powers,” and ignore individual and population preferences. Moreover, scholarly and jurist analyses repose upon an edifice of incomplete facts, and ignore the 1991 illegal annexation of Crimea by Ukraine. Crimea suffered twenty-three years of economic rot under Ukrainian rule. Under the Russian Federation, economic conditions in the peninsula are improving, despite the US/EU sanctions imposed upon the Crimean population, a cruelty that the Great Powers cannot justify. Exceptional circumstances that took place in Ukraine in 2013/14 permitted scheduling a referendum to seek independence from Ukraine. Polls taken after the 2014 referendum unanimously demonstrate that the population of Crimea and the City of Sevastopol prefer reunification with the Russian Federation, as opposed to going back and becoming a subject of Ukraine rule and exploitation under a US installed right wing regime. Repeated calls to “give back” Crimea to Ukraine are based on twisted historical narratives, solely designed to weaken the Russian Federation