Modeling economies and ecosystems in general equilibrium

This work exploits the general equilibrium modeling framework to simulate complex systems, an economy and an ecosystem. In an economic application, this work leverages a novel data revision scheme to integrate technological detail on electricity generation and pollution abatement into national accounts data in a traditional economic computed general equilibrium (CGE) model. This integration provides a rich characterization of generation and abatement for multiple fuel sources and pollutants across 72 different generation-abatement technology configurations. Results reveal that the benefits of reductions in oxides of nitrogen and sulfur from a carbon policy in the US electric sector are on the order of $10 bn., which rival the policy's welfare costs and make 12-13% carbon abatement economically justifiable without considering any climate benefits. For ecosystem applications, this work demonstrates how the structure of economic CGE modeling can be adapted to construct a Biological General Equilibrium (BGE) model grounded in the theoretical biology literature. The BGE model contributes a novel synthesis of micro-behavioral, bioenergetic features with macroscopic ecosystem outcomes and empirical food web data. Species respond to prevailing ecosystem scarcity conditions that impinge on their energy budgets driving population outcomes within and across model periods. This adaptive capacity is a critical advance over the commonly-taken phenomenological or first-order parametric approaches. The distinctive design of the BGE model enables numerical examination of how changes in scarcity drives biomass production and consumption in a complex food web. Moreover, the BGE model design can exploit empirical datasets used by extant ecosystem models to offer this level of insight for a wide cast of ecosystems. Monte carlo simulations demonstrate that the BGE framework can produce stable results for the ecosystem robust to a variety of shocks and parameterizations. The BGE model's validity is supported in tests against real-world phenomena within the Aleutian ecosystem - both an invasive species and a harvesting-induced trophic cascade - by mimicking key features of these phenomena. The BGE model's micro-founded dynamics, the stability and robustness of its results, and its validity against real-world phenomena offer a unique and valuable contribution to ecosystem modeling and a way forward for the integrated assessment of human-ecosystem interactions

The clinical spectrum of sporadic and familial forms of frontotemporal dementia

The term frontotemporal dementia (FTD) describes a clinically, genetically and pathologically diverse group of neurodegenerative disorders. Symptoms of FTD can present in individuals in their twenties through to their nineties, but the mean age at onset is in the sixth decade. The most common presentation is with a change in personality and impaired social conduct (behavioural variant FTD). Less frequently patients present with language problems (primary progressive aphasia). Both of these groups of patients can develop motor features consistent with either motor neuron disease (usually the amyotrophic lateral sclerosis variant) or parkinsonism (most commonly a progressive supranuclear palsy or corticobasal syndrome). In about a third of cases FTD is familial, with mutations in the progranulin, microtubule-associated protein tau and chromosome 9 open reading frame 72 genes being the major causes. Mutations in a number of other genes including TANK-binding kinase 1 are rare causes of familial FTD. This review aims to clarify the often confusing terminology of FTD, and outline the various clinical features and diagnostic criteria of sporadic and familial FTD syndromes. It will also discuss the current major challenges in FTD research and clinical practice, and potential areas for future research. This article is protected by copyright. All rights reserved

Walking with farmers and talking about suicidal feelings: An interpretative phenomenological analysis

There is a lack of information about how farmers in South West England experience suicidal feelings in relation to their farming identities. This study therefore adds to the limited knowledge base of the phenomenological experiences of farmers from the United Kingdom by exploring how individuals with a history of suicidal feelings and/or attempted suicide experience those feelings in relation to their identity and rural localities. This is an interview-based study using interpretative phenomenological analysis (IPA). Six male participants aged 21 and over were interviewed, all of whom had current or previous employment as a farmer in the South West of England. All interviews followed a walk-and-talk interview methodology and took place on participants’ farmland. Four super-ordinate themes are discussed: ‘It is not macho to talk about your feelings’, ‘Changes in farming and the loss of the craft’, ‘My suicide was rational’ and ‘Making sense of it all now’. These themes capture participants’ struggles with identity, masculinity and shame leading up to their feelings of suicide. The final theme captures participants’ personal growth since their suicide experience and their recovery. The results demonstrate a complex phenomenological picture of participants’ sense of masculinity and expectations on them as farmers, which fuelled their sense of personal failure and energised their decisions to consider suicide. Results indicate that farmers’ decisions to suicide are influenced by complex social and personal factors and point to an important aspect of failed masculinity. Clinical implications, limitations and avenues for future research are discussed

Neuroinflammation in frontotemporal dementia

Frontotemporal dementia (FTD) is a clinically and pathologically diverse disease with few reliable biomarkers and no effective treatments. Increasing evidence suggests that chronic neuroinflammation and microglial dysfunction contribute to disease, particularly in genetic FTD due to progranulin (GRN) mutations. This thesis examines the clinical, histological and fluid biomarker evidence of immune dysregulation and neuroinflammation in FTD, with a focus on microglia. Assessment of systemic autoimmune diseases in individuals with genetic FTD demonstrates that non-thyroid autoimmune diseases are more prevalent in GRN mutation carriers than controls. Exploration of the histopathological correlates of MRI white matter hyperintensities (WMH) in a patient with FTD due to a GRN mutation links severe WMH in the frontal lobes to extensive white matter demyelination and microglial dystrophy. Immunohistochemical assessment of microglia in frontal and temporal post-mortem brain tissue from individuals with different sporadic and genetic subtypes of frontotemporal lobar degeneration (FTLD), Alzheimer’s disease (AD) and controls demonstrates regional differences in microglial burden, activation and dystrophy, which vary by microglial phenotype, pathological subtype and disease mechanism. Measurement of levels of glia-derived biomarkers (sTREM2, YKL-40 and chitotriosidase) in cerebrospinal fluid (CSF) of individuals with sporadic and genetic FTD and controls shows that levels are elevated in certain subgroups, particularly in those with GRN mutations, or likely underlying AD rather than FTLD. Investigation of these biomarkers in CSF of presymptomatic mutation carriers (PMC) and symptomatic individuals with genetic FTD reveals raised chitotriosidase levels in GRN and MAPT mutation carriers with FTD, with elevation several years before expected onset in GRN PMC. In conclusion, this thesis provides multimodal evidence of dysregulated neuroinflammation in FTD and highlights the role of microglial dysfunction and senescence in the pathogenesis of FTLD, particularly in GRN mutation carriers. Further investigation of these processes may guide therapeutic and biomarker approaches for use in future clinical trials

The Social Health Atlas : a policy tool to describe and monitor social inequality and health inequality in Australia

En 1988, como respuesta a la toma de conciencia del papel que las desigualdades sociales juegan en las desigualdades relacionadas con la salud, la Oficina para la Salud Social de la Comisión de Salud de Australia Meridional propuso la adopción de una estrategia en salud social. La estrategia en salud social adoptó una visión, para mejorar la salud de los habitantes de Australia Meridional, basada en el reconocimiento de políticas externas al sector sanitario que pueden tener un impacto importante sobre la salud de la comunidad en general y de los grupos más desfavorecidos en particular. Entre estas políticas externas a la salud destacan la vivienda, la educación y el transporte. En su conjunto, esta visión se conoce como "aproximación social a la salud". Como parte de esta estrategia, la información se percibe como una componente importante al facilitar la descripción de perfiles socioeconómicos y de salud en la población. Los mapas fueron elegidos como el mejor instrumento para presentar y transmitir este tipo de información. Los mapas presentan la información de tal forma que ésta se hace accesible a audiencias heterogéneas, no sólo para aquellas encargadas de establecer políticas e implementar estrategias sino también a los consumidores y a otros actores sociales que podrían tener limitaciones a la hora de manejar información estadística presentada de forma más tradicional. Los mapas del atlas que se presenta describen la distribución geográfica de la población a través de un amplio rango de indicadores socioeconómicos, su estado de salud y el uso que hace de los servicios sanitarios, subrayando, por tanto, las relaciones existentes entre los indicadores de desigualdad social y las condiciones de desigualdad en salud. Ésta es la razón por la el atlas recibe el nombre de "Atlas Socio-sanitario". Durante los catorce años que han transcurrido desde que el primer atlas socio-sanitario fue publicado, la variedad y calidad de las bases de datos existentes a nuestra disposición ha mejorado considerablemente, lo que permite una mejorada comprensión del impacto que las condiciones socioeconómicas ejercen sobre la salud. Esta mejora ha permito, asimismo, analizar tendencias temporales y patrones de distribución espacial. Los atlas representan una iniciativa de gran calado en los esfuerzos por reforzar la información sobre las infraestructuras de salud pública en Australia y constituyen una herramienta de importancia mayor en las políticas dirigidas a problemas relacionados con desigualdades sanitarias cuyo origen se encuentra en la desigualdad social.In 1988, in response to an increasing awareness in Australia of the role of social inequality as a key to health inequality, the Social Health Office within the South Australian Health Commission proposed the adoption of a social health strategy. The social health strategy outlined an approach to improving health for all South Australians through a recognition that policies in areas outside of the health sector, such as housing, education, transport etc. can have substantial impact on the health of the general community, and in particular on disadvantaged groups. This is often referred to as a 'social view of health'. Information was seen as having an important part in this strategy, by describing the socioeconomic and health status profiles of the population. The approach chosen to presenting information was through mapping. Maps present data in a way that is accessible to a wide audience, not only those charged with setting policy and undertaking strategic planning, but to consumers and other community advocates who may have limited skills in handling statistical information presented in more traditional ways. The maps describe the geographic distribution of the population by a range of socioeconomic indicators, together with maps showing their health status and use of health services, thereby highlighting the relationships between the indicators of socioeconomic inequality and inequality in health status. These reports have been titled 'social health atlases'. Over the fourteen years since the first social health atlas was released, the range and quality of datasets has improved, allowing for a better understanding of the impact of socioeconomic influences on health. It has also been possible to address changes in the overall levels, and patterns in the distribution, of socioeconomic status and health status and to assess the extent to which the health divide has been addressed. The atlases represent a major initiative in strengthening the public health information infrastructure in Australia and are a major policy tool with which to address health inequality arising from social inequality

Postural Dysfunction During Standing and Walking in Children With Cerebral Palsy: What are the Underlying Problems and What New Therapies Might Improve Balance?

In this review we explore studies related to constraints on balance and walking in children with cerebral palsy (CP) and the efficacy of training reactive balance (recovering from a slip induced by a platform displacement) in children with both spastic hemiplegic and diplegic CP. Children with CP show (a) crouched posture, contributing to decreased ability to recover balance (longer time/increased sway); (b) delayed responses in ankle muscles; (c) inappropriate muscle response sequencing; (d) increased coactivation of agonists/antagonists. Constraints on gait include (a) crouched gait; (b) increased co-activation of agonists/antagonists; (c) decreased muscle activation; (d) spasticity. The efficiency of balance recovery can be improved in children with CP, indicated by both a reduction in the total center of pressure path used during balance recovery and in the time to restabilize balance after training. Changes in muscle response characteristics contributing to improved recovery include reductions in time of contraction onset, improved muscle response organization, and reduced co-contraction of agonists/antagonists. Clinical implications include the suggestion that improvement in the ability to recover balance is possible in school age children with CP

The Social Health Atlas : a policy tool to describe and monitor social inequality and health inequality in Australia

En 1988, como respuesta a la toma de conciencia del papel que las desigualdades sociales juegan en las desigualdades relacionadas con la salud, la Oficina para la Salud Social de la Comisión de Salud de Australia Meridional propuso la adopción de una estrategia en salud social. La estrategia en salud social adoptó una visión, para mejorar la salud de los habitantes de Australia Meridional, basada en el reconocimiento de políticas externas al sector sanitario que pueden tener un impacto importante sobre la salud de la comunidad en general y de los grupos más desfavorecidos en particular. Entre estas políticas externas a la salud destacan la vivienda, la educación y el transporte. En su conjunto, esta visión se conoce como "aproximación social a la salud". Como parte de esta estrategia, la información se percibe como una componente importante al facilitar la descripción de perfiles socioeconómicos y de salud en la población. Los mapas fueron elegidos como el mejor instrumento para presentar y transmitir este tipo de información. Los mapas presentan la información de tal forma que ésta se hace accesible a audiencias heterogéneas, no sólo para aquellas encargadas de establecer políticas e implementar estrategias sino también a los consumidores y a otros actores sociales que podrían tener limitaciones a la hora de manejar información estadística presentada de forma más tradicional. Los mapas del atlas que se presenta describen la distribución geográfica de la población a través de un amplio rango de indicadores socioeconómicos, su estado de salud y el uso que hace de los servicios sanitarios, subrayando, por tanto, las relaciones existentes entre los indicadores de desigualdad social y las condiciones de desigualdad en salud. Ésta es la razón por la el atlas recibe el nombre de "Atlas Socio-sanitario". Durante los catorce años que han transcurrido desde que el primer atlas socio-sanitario fue publicado, la variedad y calidad de las bases de datos existentes a nuestra disposición ha mejorado considerablemente, lo que permite una mejorada comprensión del impacto que las condiciones socioeconómicas ejercen sobre la salud. Esta mejora ha permito, asimismo, analizar tendencias temporales y patrones de distribución espacial. Los atlas representan una iniciativa de gran calado en los esfuerzos por reforzar la información sobre las infraestructuras de salud pública en Australia y constituyen una herramienta de importancia mayor en las políticas dirigidas a problemas relacionados con desigualdades sanitarias cuyo origen se encuentra en la desigualdad social.In 1988, in response to an increasing awareness in Australia of the role of social inequality as a key to health inequality, the Social Health Office within the South Australian Health Commission proposed the adoption of a social health strategy. The social health strategy outlined an approach to improving health for all South Australians through a recognition that policies in areas outside of the health sector, such as housing, education, transport etc. can have substantial impact on the health of the general community, and in particular on disadvantaged groups. This is often referred to as a 'social view of health'. Information was seen as having an important part in this strategy, by describing the socioeconomic and health status profiles of the population. The approach chosen to presenting information was through mapping. Maps present data in a way that is accessible to a wide audience, not only those charged with setting policy and undertaking strategic planning, but to consumers and other community advocates who may have limited skills in handling statistical information presented in more traditional ways. The maps describe the geographic distribution of the population by a range of socioeconomic indicators, together with maps showing their health status and use of health services, thereby highlighting the relationships between the indicators of socioeconomic inequality and inequality in health status. These reports have been titled 'social health atlases'. Over the fourteen years since the first social health atlas was released, the range and quality of datasets has improved, allowing for a better understanding of the impact of socioeconomic influences on health. It has also been possible to address changes in the overall levels, and patterns in the distribution, of socioeconomic status and health status and to assess the extent to which the health divide has been addressed. The atlases represent a major initiative in strengthening the public health information infrastructure in Australia and are a major policy tool with which to address health inequality arising from social inequality

Ontogenies of Phototactic Behavior and Metamorphic Competence in Larvae of Three Species of \u3cem\u3eBugula\u3c/em\u3e (Bryozoa)

The free swimming larvae of many marine invertebrates actively respond to light. Light cues can be used to regulate position in the water column and to facilitate encountering sites suitable for metamorphosis. We examined the ontogeny of larval phototaxis and the ontogeny of metamorphic competency in larvae from three congeneric species of bryozoans. Larvae of Bugula neritina are positively phototactic on emergence from the brood chamber, whereas larvae of B. simplex and B. stolonifera appear initially photoneutral when populations of larvae are examined. Larvae of all three species become photonegative with time. Temporally coincident with this change to negative phototaxis is an increase in the competency of larvae to initiate metamorphosis. This observation suggests that these events are either physiologically linked or co-occurring, but independent developmental processes. We tested these hypotheses by artificially changing the sign of phototaxis from positive to negative using 10-5 M bath- applied 5-hydroxytryptamine (5HT) in larvae of B. neritina that were swimming for 1 h. Larvae that were photopositive and 1-h-old did not metamorphose at levels significantly different from larvae that were 1-h-old and treated with 5HT (i.e., young, photonegative larvae). Additionally, photopositive larvae which were swimming for 4 h initiated metamorphosis at rates nearly identical to photonegative larvae of the same age. Our data document that in larvae of B. neritina the changes in sign of phototaxis and levels of metamorphic competency are independent developmental events that occur in temporal coincidence. The concurrent timing of these two pathways may have been synchronized through selective processes resulting in a tight coupling between arrival at potentially suitable sites for metamorphosis and ability to respond to metamorphic cues

Electronic and Plasmonic Properties of Real and Artificial Dirac Materials

Inspired by graphene, I investigate the properties of several different real and artificial Dirac materials. Firstly, I consider a two-dimensional honeycomb lattice of metallic nanoparticles, each supporting localised surface plasmons, and study the quantum properties of the collective plasmons resulting from the near field dipolar interaction between the nanoparticles. I analytically investigate the dispersion, the effective Hamiltonian and the eigenstates of the collective plasmons for an arbitrary orientation of the individual dipole moments. When the polarisation points close to normal to the plane the spectrum presents Dirac cones, similar to those present in the electronic band structure of graphene. I derive the effective Dirac Hamiltonian for the collective plasmons and show that the corresponding spinor eigenstates represent chiral Dirac-like massless bosonic excitations that present similar effects to those of electrons in graphene, such as a non-trivial Berry phase and the absence of backscattering from smooth inhomogeneities. I further discuss how one can manipulate the Dirac points in the Brillouin zone and open a gap in the collective plasmon dispersion by modifying the polarisation of the localized surface plasmons, paving the way for a fully tunable plasmonic analogue of graphene. I present a phase diagram of gapless and gapped phases in the collective plasmon dispersion depending on the dipole orientation. When the inversion symmetry of the honeycomb structure is broken, the collective plasmons become gapped chiral Dirac modes with an energy-dependent Berry phase. I show that this concept can be generalised to describe many real and artificial graphene-like systems, labeling them Dirac materials with a linear gapped spectrum. I also show that biased bilayer graphene is another Dirac material with an energy dependent Berry phase, but with a parabolic gapped spectrum. I analyse the relativistic phenomenon of Klein Tunneling in both types of system. The Klein paradox is one of the most counter-intuitive results from quantum electrodynamics but it has been seen experimentally to occur in both monolayer and bilayer graphene, due to the chiral nature of the Dirac quasiparticles in these materials. The non-trivial Berry phase of pi in monolayer graphene leads to remarkable effects in transmission through potential barriers, whereas there is always zero transmission at normal incidence in unbiased bilayer graphene in the npn regime. These, and many other 2D materials have attracted attention due to their possible usefulness for the next generation of nano-electronic devices, but some of their Klein tunneling results may be a hindrance to this application. I will highlight how breaking the inversion symmetry of the system allows for results that are not possible in these system’s inversion symmetrical counterparts