Supersymmetric representations and many-particle states

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Welcome to Parks Stewardship Forum: An Introduction to the Journal from the Editors

An overview of Parks Stewardship Forum from the managing editors, published in the inaugural issue of the journal, whose theme is "Climate Change and Protected Places: Adapting to New Realities.

Organosolv pretreatment of Sitka spruce wood: conversion of hemicelluloses to ethyl glycosides

A range of organosolv pretreatments, using ethanol:water mixtures with dilute sulphuric acid, were applied to Sitka spruce sawdust with the aim of generating useful co-products as well as improving saccharification yield. The most efficient of the pretreatment conditions, resulting in subsequent saccharification yields of up to 86%, converted a large part of the hemicellulose sugars to their ethyl glycosides as identified by GC/MS. These conditions also reduced conversion of pentoses to furfural, the ethyl glycosides being more stable to dehydration than the parent pentoses. Through comparison with the behaviour of model compounds under the same reaction conditions it was shown that the anomeric composition of the products was consistent with a predominant transglycosylation reaction mechanism, rather than hydrolysis followed by glycosylation. The ethyl glycosides have potential as intermediates in the sustainable production of high-value chemicals

Structural and Magnetic Phases in Pressure-Tuned Quantum Materials

This thesis presents work exploring the use of pressure as a tuning parameter for exploring the phase diagrams and properties of magnetically ordered insulators, to add understanding to several areas of current interest in condensed matter research. It shows the versatility of pressure as an experimental technique for exploring material properties free from complicating factors which arise with similar techniques such as chemical doping. The properties of low-dimensional magnetic materials, and how these systems respond as they are pushed toward a more three-dimensional nature is explored through studies of both the crystal and magnetic structures of the family of quasi-two-dimensional magnetic insulators MPS3 (M = Fe, Ni, Mn). With previous work largely being specific to individual compounds, this thesis contributes to a more unified understanding of their properties. It shows that Ni and MnPS3 undergo similar structural transitions under pressure to those previous observed in FePS3, the highest pressure of which is linked to an insulator-to-metal transition in that system. Through record high-pressure neutron diffraction measurements, the evolution of the antiferromagnetic order in FePS3 through this metallisation is studied for the first time. In contradiction to previous indirect measurements, it is seen that magnetism persists into the metallic phase, with long range antiferromagnetism giving way to a previously unobserved short-range order. This work is relevant on a broader scale for numerous layered magnetic materials such as cuprate high temperature superconductors. Secondly, pressure is used to explore the magnetocaloric properties of the antiferromagnet EuTiO3. Recent work has shown that this compound compares favourably to many materials commonly used in magnetic refrigeration. Measurements show that these properties are suppressed by the application of pressure and point towards the potential existence of a previously undiscussed transition in the material between 0.4 GPa and 0.5 GPa

Immigration, asylum, and cycles of European exclusion

The hypothesis of this thesis is that hidden behind the European legal approach to issues of Immigration and asylum is the deeply embedded European philosophy of exclusion. The thesis argues that exclusion has its roots in historical interpretations of Difference and Otherness. It is cyclical in nature, and the identity of groups targeted for exclusion changes over time. The thesis argues that the practice of exclusion has been honed and perfected into a societal norm from which exclusionary law claims legitimacy. It goes on to develop the idea that exclusion is a reflection of a deeper societal unease rooted somewhere in European history culture and philosophy, the influence of which continues to have a deleterious effect on contemporary attitudes towards immigration and asylum, and on the corresponding laws of the European Union and its member states. Whilst law indicates the methods and grounds of exclusion it does not indicate the philosophy and psyche behind the law.In order to test the hypothesis, the thesis explores the social and legal history of exclusion in Europe from the 19th century to the present time. It strives to establish the identities of the excluded in the pre-first World War European Empires, and suggests that they were essentially defined by their Europeanness, and often based on internecine conflict. The thesis goes on to look for similarities in the identities of the excluded of the interwar years, and notes how issues of race resurfaced to form a new ideology. The chronology continues by exploring the post Second World War period, and notes how the identities of those who occupied the symbolic space of exclusion evolved from an essentially European identity, to new non-European characteristics, linked to the rise of non-European immigration.The thesis therefore suggests that Difference, Otherness and Exclusion have evolved into a societal norm from which exclusionary law claims legitimacy. It suggests that the concepts of Difference Otherness and Exclusion continue to influence contemporary society, and suggests that Europe remains preoccupied with issues of identity and of responding to these issues in a traditional exclusionary manner.Finally the thesis begins to consider whether the animosity and mistrust previously reserved for the European Jewry is now being re-focused on Europe’s Muslim community. It asks if the restrictions on the entry into Europe of those fleeing conflict in the Middle East, and of those who hail from the Indian sub-continent and who wish to settle in Europe, are an expression of a new cycle of exclusionary practice where only the identity of the excluded has changed.Therefore the thesis aims to contribute to knowledge by re-visiting some of the ambiguities inherent in European history, law and society; and challenge assumptions of what gives rise to pejorative attitudes towards immigration and asylum. Through the exercise of independent critical analysis it aims at a new interpretation of known facts. By applying theoretical interpretations to historical and contemporary narrative, the thesis seeks to demonstrate that the identity of the excluded is seldom static, and advances the idea that exclusion, based on ethnicity or religion or gender - the list is not exhaustive – has cyclical characteristics. In terms of law and scholarship it is of societal benefit to understand who were the excluded of the past – and why; who are the currently excluded – and why; and how, given an understanding of the past and the present, it may be possible to forecast who are to be the future excluded, and why this might be so

Effective engagement of conservation scientists with decision-makers

This chapter offers advice on how the conservation science community can effectively engage with decision-makers. The rationales for why we, as scientists, need to do this have been widely discussed in the literature. Often, the reasons offered are normative, pragmatic, or instrumental (de Vente, 2016); in other words, there is a belief that engaging with decision-makers leads to better informed, more acceptable decisions. Indeed, better engagement may lead to the greater uptake of evidence for conservation decisions, something which some scholars argue is a priority for effective management (e.g. Gardner et al., 2018; Sutherland and Wordley, 2017)

Isolation of high quality lignin as a by-product from ammonia percolation pretreatment of poplar wood

A two-step process combining percolation-mode ammonia pretreatment of poplar sawdust with mild organosolv purification of the extracted lignin produced high quality, high purity lignin in up to 31% yield and 50% recovery. The uncondensed fraction of the isolated lignin was up to 34%, close to that the native lignin (40%). Less lignin was recovered after pretreatment in batch mode, apparently due to condensation during the longer residence time of the solubilised lignin at elevated temperature. The lignin recovery was directly correlated with its molecular weight and its nitrogen content. Low nitrogen incorporation, observed at high ammonia concentration, may be explained by limited homolytic cleavage of -O-4 bonds. Ammonia concentrations from 15% to 25% (w/w) gave similar results in terms of lignin structure, yield and recovery