Off the Grid

Off the Grid explores the messy relationship between public and private perceptions of our urban spaces, especially the tensions created when lived experience runs up against the physical and conceptual networks of cities: street grids, construction tape, and property lines. Incorporating different modes of spatial representation, from cartographic diagrams to isometric illustrations and Renaissance perspectives, this exhibition examines the role drawing plays in how we conceptualize the divisions and definitions of everyday space. The drawings engage the often overlooked detritus of city life, from layers of old graffiti to overgrown dirt piles and unmoored electrical wiring, that complicate our understanding of how urban space is actually used. Drawn from the spaces surrounding the artist’s daily routine, Off the Grid investigates the potential of a subjective cartography to tell a more complete story about the places we inhabit

The Son of God and Trinitarian Identity Statements

Classical Trinitarians claim that Jesus—the Son of God—is truly God and that there is only one God and the Father is God, the Spirit is God, and the Father, Son, and Spirit are distinct. However, if the identity statement that ‘the Son is God’ is understood in the sense of numerical identity, logical incoherence seems immanent. Yet, if the identity statement is understood according to an ‘is’ of predication then it lacks accuracy and permits polytheism. Therefore, we argue that there is another sense of ‘is’ needed in trinitarian discourse that will allow the Christian to avoid logical incoherence while still fully affirming all that is meant to be affirmed in the confession ‘Jesus is God.’ We suggest a sense of ‘is’ that meets this need

Mental Capacity and Decisional Autonomy: An Interdisciplinary Challenge

With the waves of reform occurring in mental health legislation in England and other jurisdictions, mental capacity is set to become a key medico-legal concept. The concept is central to the law of informed consent and is closely aligned to the philosophical concept of autonomy. It is also closely related to mental disorder. This paper explores the interdisciplinary terrain where mental capacity is located. Our aim is to identify core dilemmas and to suggest pathways for future interdisciplinary research. The terrain can be separated into three types of discussion: philosophical, legal and psychiatric. Each discussion approaches mental capacity and judgmental autonomy from a different perspective yet each discussion struggles over two key dilemmas: whether mental capacity and autonomy is/should be a moral or a psychological notion and whether rationality is the key constitutive factor. We suggest that further theoretical work will have to be interdisciplinary and that this work offers an opportunity for the law to enrich its interpretation of mental capacity, for psychiatry to clarify the normative elements latent in its concepts and for philosophy to advance understanding of autonomy through the study of decisional dysfunction. The new pressures on medical and legal practice to be more explicit about mental capacity make this work a priority

Global change drivers and their impact on herbaceous, ant, and grasshopper assemblages in an African semi-arid savanna

Assessments of the anthropogenic threats to savanna ecosystems are primarily focussed on land use change, bush encroachment, and biological invasions. There is, however, very little understanding as to the threats from atmospheric pollution. South Africa is the major emitter of CO2 on the African content while the Mpumalanga region bordering the Kruger National Park (KNP) is among the leading regions for nitrous oxide pollution in the world. It is not only increasing atmospheric pollution, but rainfall intensity is also predicted to increase for southern Africa. As savannas are nutrient limited, an increase in nitrogen deposition will have major consequences for vegetation structure and this can only be exacerbated by increased rainfall amounts. Current research suggests that these predicted increases in water and nutrients will result in increasing grass biomass and decreasing herbaceous species richness. The effects of global change drivers on savanna vegetation are also likely to propagate through to multiple trophic levels, with changes in vegetation structure cascading down to invertebrate assemblages. As invertebrates are ubiquitous, form the bulk of metazoan species diversity and biomass on earth, and play a pivotal role in many ecosystems, I discuss in the introductory chapter of this thesis why the influence of global change on these assemblages should not be ignored. In my first data chapter, Chapter 2, I examine the effect that increases in available nutrients and water may have on vegetation structure, and how this may cascade down to grasshopper and ant assemblages. I do this using a fully factorial experiment in KNP with nutrient and water additions where I assessed both herbaceous (forb and grass) and insect (ant and grasshopper) assemblages five years after resource additions began. My results show that there was a substantial increase in grass biomass while plant and insect species richness declined with water addition alone and that a combination of nutrients and water resulted in the greatest increases in grass biomass and concomitant decreases in plant and insect species richness. The effects of nutrient and water additions on the insect community assembly was primarily driven by a decrease in grasshopper species and ant abundance respectively. An analysis of ant functional traits showed that the rare ant species mediated the impact of the resource additions on the ant assemblage. Fire is inherent to savanna systems with profound effects on vegetation structure. There has, however, been relatively little research on the effects of fire on savanna invertebrate fauna. In Chapter 3 I look at the effect that fire may have on the vegetation and insect community assembly at my study site between five and eight months after the site had been burned. These results show an increase in grass biomass and decrease in plant and insect species richness with a combination of nutrients and water. My results also show that grasshopper biomass, abundance, and species richness decreased as herbaceous biomass decreased. While ant species richness decreased, ant abundance increased post-fire, primarily related to an increase in patches of bare ground. With global change, drought frequency is also expected to increase. The insect and grass assemblages, both on and off Macrotermes mounds, at two sites in the southern section of KNP had been sampled in a separate study in 2012. In Chapter 4 I describe a study where I resampled these mounds during the peak of the most severe drought in 30 years. The two sites differed in drought severity, one where the drought severity was very high and the other where severity was much lower. The objective was to determine the effects that drought may have on the grass and associated insect assemblages both on and off termite mounds. My results show that at the high severity site grass cover and biomass and grasshopper abundance decreased both on and off mounds. The overall reduction in habitat structure resulted in an increase in both ant abundance and species richness but the mound and matrix ant assemblages diverged during drought. Where the drought was less severe there was an increase in large mammal herbivores as animals moved out of the more affected areas. This increase in mammal herbivory was more evident on rather than off mounds resulting in grass biomass being lower on rather than off mounds. The cascading effect saw grasshopper abundance decrease on and increase off mounds. The mound and matrix ant assemblages did not respond to the comparatively smaller change in habitat structure. Finally, in the synthesis chapter I discuss my results in the broader context of how global change drivers such as increased nitrogen deposition may cascade down from plant to insect community assembly. At present there is very little understanding of the amounts of nitrogen being deposited in KNP or the effect that this may have. The results of my study would suggest that this increase in nitrogen deposition will have major consequences for vegetation structure and that this will cascade down to the insect assemblage. In mitigating for this, it is therefore essential that management in KNP adapt a monitoring protocol for nitrogen deposition, especially when considering that where N deposition is really high fire may not volatilise everything to allow the system to reset itself back to its original state. It is not only nitrogen deposition, but drought frequency is also likely to increase. In mitigation for this there should also be monitoring programmes to consider the effects of drought as animals may move from areas of high drought severity to areas where severity is lower. Such movement will increase grazing pressure on both low and high nutrient environments with cascading effects on vegetation structure and insect assemblages

Experimental fast-ion transport studies on the Mega-Amp Spherical Tokamak

Nuclear fusion holds the promise of a sustainable means of electrical power generation. The technical challenge posed by controlled nuclear fusion however is formidable. One key aspect of research into magnetically-confined fusion plasmas is the study of the behaviour of fast ions. Produced by auxiliary heating systems including neutral beam injection (NBI) and ion cyclotron resonance heating, as well as by the fusion reactions themselves, the energies of these particles range from tens of keV to several MeV. Four fast-ion diagnostics on a medium-sized experimental fusion research device, namely the Mega-Amp Spherical Tokamak (MAST), have been used to investigate the transport of NBI-generated fast ions under the influence of various magnetohydrodynamic (MHD) instabilities. These include frequency-chirping fast-ion-driven modes known as toroidal Alfv\'{e}n eigenmodes (TAE) and fishbones, as well as saturated internal kink modes and sawtooth reconnection events. The frequencies of these modes in the plasma frame ranged from 0 - 150 kHz in MAST. The effects of these modes on the fast ions have been investigated with the use of a fission chamber, a collimated neutron detector, a fast-ion deuterium alpha spectrometer and a charged fusion product detector. Data from each diagnostic are examined and compared for consistency in the presence of each type of instability. Fast-ion transport modelling is coupled with synthetic diagnostics to model the observed signals based on calculated fast-ion distributions. The data reveal a significant enhancement of fast-ion transport due to each of the MHD modes. It is found that the transport of fast ions in the presence of TAE and fishbones, averaged over the chirping mode cycle, is well-represented by assuming anomalous radial diffusion of these ions. A simple model for fast-ion mixing during sawtooth reconnection is found to reproduce partially the observations accompanying such events. The effects of the saturated internal kink mode cannot be modelled in such a simple way, and partial consistency with the measurements requires the use of tailored transport coefficients. Shortcomings and possible enhancements of the diagnostic capability are discussed in the light of these results

Automated classification of three-dimensional reconstructions of coral reefs using convolutional neural networks

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Hopkinson, B. M., King, A. C., Owen, D. P., Johnson-Roberson, M., Long, M. H., & Bhandarkar, S. M. Automated classification of three-dimensional reconstructions of coral reefs using convolutional neural networks. PLoS One, 15(3), (2020): e0230671, doi: 10.1371/journal.pone.0230671.Coral reefs are biologically diverse and structurally complex ecosystems, which have been severally affected by human actions. Consequently, there is a need for rapid ecological assessment of coral reefs, but current approaches require time consuming manual analysis, either during a dive survey or on images collected during a survey. Reef structural complexity is essential for ecological function but is challenging to measure and often relegated to simple metrics such as rugosity. Recent advances in computer vision and machine learning offer the potential to alleviate some of these limitations. We developed an approach to automatically classify 3D reconstructions of reef sections and assessed the accuracy of this approach. 3D reconstructions of reef sections were generated using commercial Structure-from-Motion software with images extracted from video surveys. To generate a 3D classified map, locations on the 3D reconstruction were mapped back into the original images to extract multiple views of the location. Several approaches were tested to merge information from multiple views of a point into a single classification, all of which used convolutional neural networks to classify or extract features from the images, but differ in the strategy employed for merging information. Approaches to merging information entailed voting, probability averaging, and a learned neural-network layer. All approaches performed similarly achieving overall classification accuracies of ~96% and >90% accuracy on most classes. With this high classification accuracy, these approaches are suitable for many ecological applications.This study was funded by grants from the Alfred P. Sloan Foundation (BMH, BR2014-049; https://sloan.org), and the National Science Foundation (MHL, OCE-1657727; https://www.nsf.gov). The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript

2014 Fed Challenge Script: Current State of the Economy

Good afternoon everyone and thank you for having us here today. Though the recession began in 2007 and officially ended in 2009, recovery has been painfully slow. GDP growth has been insufficient to close the output gap, there continues to be slack in the labor market and inflation has stabilized below the Federal Reserve percent target. We are not meeting our dual mandate of full employment and stable prices even 6 years after the end of the recession. Despite some signs of strengthening in the economy during the past year, we do not believe that economy is on a self-sustaining path of recovery. Furthermore, the monetary policy actions taken by the Fed thus far to pull us out of the Great Recession have been insufficient. We propose a substantial strengthening of the our forward guidance; specifically, a commitment not to raise the federal funds rate until nominal GDP has returned to a path that we consider consistent with the dual mandate. [excerpt