Abstract Purpose: To compare the frequency specific Cortical Auditory Evoked Potential (CAEP) and the chirp-evoked 40 Hz Auditory Steady State Response (ASSR) with equivalent residual noise levels for behavioural threshold prediction in adults with normal hearing and with SNHL. Method: The study tested 23 adults with normal hearing and 20 adults with SNHL. The participants were aged between 18–65 years. A repeated measures within- participant descriptive design was used to collect the quantitative data. The participants underwent behavioural pure tone, CAEP and ASSR testing on the same day. Results: Similar CAEP difference scores across frequencies for the participants with normal hearing (mean=12.32-14.40 dB) and with SNHL (mean=10.00-16.47 dB) were measured. However, for the ASSR difference scores across frequencies slightly smaller difference scores were measured for the participants with SNHL (mean=10.17-17.30 dB) than for the participants with normal hearing (mean=11.74- 17.14 dB). CAEP thresholds were significantly closer to the behavioural pure tone thresholds at 500 (p=0.028; mean absolute difference 14.40 dB) and 2000 (p=0.016; mean absolute difference 12.56 dB) Hz for participants with normal hearing. In participants with sensorineural hearing loss, CAEP and ASSR thresholds were measured at similar sensation levels and were not statistically different (p>0.05). Conclusion: For the purpose of threshold estimation, representing the auditory function to the level of the auditory cortex the CAEP was closer to the behavioural hearing thresholds than the 40 Hz ASSR at all frequencies except at 4000 Hz, regardless of the hearing sensitivity. Keywords: Auditory steady state response (ASSR), Cortical auditory evoked potential (CAEP), Auditory evoked potential (AEP), Residual noise, Signal to noise ratio (SNR), objective threshold estimation, awake adults. / Dissertation (MA (Audiology))--University of Pretoria, 2019. / Speech-Language Pathology and Audiology / MA Audiology / Unrestricted

Academic studies of sustainable fashion, and the discourses of actors in business and policy, under-define fashion as a system by treating the social and ecological aspects of fashion separately. This reduces the potential for academic findings to provide knowledge useful for transformation of the fashion system and obstructs desired outcomes from policy and business responses to fashion’s negative social and environmental impacts. Understanding how fashion works as a system presents a challenge to transdisciplinary efforts for transformation towards sustainability. In this Licentiate, I explore ways to look at fashion using a feminist critical realist social-ecological system approach. I develop a theoretical framework to understand the fashion system, and particularly to understand what is keeping it unsustainable. I view fashion as a ‘nested’ social-ecological system with inseparable social and biophysical parts.  I use a feminist lens characterized by diversity; this draws attention to gaps, what is known, missing and absent. To show that social aspects and material aspects are intertwined and cannot be studied independently of each other, I use critical realism as a metatheory. I bring its idea of a stratified reality and the model of the four-planar social being to the social-ecological system approach that forms the core of my work. I combine Ostrom’s frequently used general framework for analysing social-ecological systems with a policy-oriented framework for sustainable development. Drawing from these two frameworks I develop a five principles for a strategy framework for sustainable fashion. In summary, applying the strategy framework within the theoretical framework enables thinking more deeply about the structure and implications of knowledge contributions when taking a social-ecological perspective on actions for sustainability.  The two papers in this licentiate thesis examine the effects of ontological standpoints that allow environmental impacts of textile fibres to be analysed in isolation from the cultural and social aspects of fashion.    Paper 1, ‘Making Resilient Decisions for Sustainable Circularity of Fashion’, is recently published in the journal Circular Economy and Sustainability (Palm et al. 2021). It aimed to show how current circularity responses to global sustainability challenges have so far fallen short. The current path of the expanding fashion industry is fraught with accelerated material throughputs and increased disposal and waste, contributing to human-driven environmental changes at planetary scale. In addition the fashion industry has issues of poor working conditions, modern-day slavery, and justice. By representing a Driver – State – Response framework as an adaptive cycle of a social-ecological system, it makes it clear that reducing planetary pressure from the global fashion and textiles industry requires greater recognition of the system’s social drivers. This paper was a step towards the iterative development of my sustainable fashion framework.   Paper 2, ‘Reviewing and defining the concept of Sustainable Fashion: a critical social-ecological approach’, is included as an early-stage draft manuscript. It aims to provide a starting point for discussions towards a coherent science-business-policy definition of the concept of sustainable fashion itself. Using the five theoretically grounded principles of my strategy framework, I examine the manifold definitions related to sustainable fashion such as eco fashion, green fashion, ethical fashion, slow fashion, organic fashion and cradle-to-cradle-fashion. Critical realism’s idea of absence structures this paper.  This thesis contributes to knowledge of what a nested inseparable social-ecological system fashion is, enriching ontological descriptions for resilience research more generally.  Also, it provides concrete guidance for transdisciplinary efforts with business and policy working to decrease fashion’s negative impacts on humans and the planet, by showing that fruitful responses pay attention to social activities beyond the industry value chain, not just material flows within. Finally,  I hope my research serves as a contribution to propaedeutics of the field of sustainable fashion, i.e. giving an introductory understanding of the reality and the possibilities of fashion for people and planet. / <p>The work presented here was part of a consortium research project between Stockholm Resilience Centre and the Ellen MacArthur Foundation, initiated and funded by H&amp;M Group, the Swedish public limited company. Celinda Palm, Sarah Cornell and Tiina Häyhä’s employment was part-funded through this project.</p>

On the way towards a more biobased economy, the sustainable use of global wood resources remains a challenge as several trade-offs arise, e.g., from an increased energetic use of wood, an increased use of innovative but probably less recyclable wood composites, or from the need to conserve other forest ecosystem services. The aim of this study is to identify existing environmental indicators and methods for an evaluation of the sustainability of wood products in consideration of all life cycle stages, site-dependent aspects and later use in corporate decision-making. We chose a systematic literature review to answer the research questions explicitly and comprehensively. Qualitative content analysis was used to code indicators and scientific methods according to the Pressure-State-Response (PSR) framework. The sample (N = 118) is characterized by a high number of life cycle assessment (LCA) case studies. In 51% of all studies, the study authors use a combination of different methods. A total of 78 indicators and 20 site-dependent aspects could be identified in the sample. The study findings represent a first step towards a holistic environmental assessment of wood products.

There has always been a need for objective tests that assess auditory function in infants, young children, and/or any patient whose development level precludes the use of behavioral audiometric techniques. Although the Auditory Brainstem Response (ABR) is seen as the ‘gold standard’ in the field of objective audiometry, it presents with its own set of limitations. The Auditory Steady State Response (ASSR) has gained considerable attention and is seen as a promising addition to the AEP ‘family’ to address some of the limitations of the ABR. The ASSR promises to estimate all categories of hearing loss (mild to profound) in a frequency specific manner. It also indicates to the possibility to validate hearing aid fittings by determining functional gain of hearing aids by determining unaided and aided ASSR thresholds. An exploratory research design was selected in order to compare unaided thresholds, obtained through the use of three different procedures – ABR, ASSR and behavioral thresholds. Aided thresholds were also obtained and compared with two procedures – the aided ASSR (measured and predicted) and aided behavioral threshold. The results indicated that both the ABR (tone burst and click) and ASSR provided a reasonable estimation of the subsequently obtained behavioral audiograms. The ASSR, however, approximated the behavioral thresholds closer than the ABR and were furthermore able to quantify hearing thresholds accurately for subjects with severe and profound hearing losses. The result indicated further that the ASSR can be instrumental in the validation process of hearing aid fittings in infants. These results demonstrated however, that the ASSR measured thresholds underestimate the aided behavioral thresholds and the aided ASSR predicted thresholds overestimate the aided behavioral thresholds. The research concluded that the ASSR is useful in estimating frequency-specific behavioral thresholds accurately in infants and validating hearing aid fittings. Until evidence is sufficient to recommend the ASSR as primary electrophysiological measure of hearing in infants, the ASSR should be used in conjunction with the ABR – following a test battery approach in the diagnostic process of hearing loss in infants. The ASSR further shows great promise in validating hearing aid fittings, but this specific application of the ASSR needs further research evidence on large groups to validate the procedure. / Dissertation (Master of Communication Pathology)--University of Pretoria, 2007. / Speech-Language Pathology and Audiology / unrestricted

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The application of environmental performance indicators (EPIs) has received increasing attention by both governments and international organisations as a tool for assessing complex environmental scenarios in national and local decision making processes. However, at the regional scale there is a gap in the application of EPIs, as this has not been well understood and defined due to a limited theoretical foundation and often insufficient data from all participant countries. The regional scale is important because it can incorporate natural ecosystems which often transcend national boundaries. A case study is developed for the Lower Mekong Subregion (LMS), where four riparian Southeast Asian countries (Lao PDR, Thailand, Cambodia, and Viet Nam) share the Lower Mekong River. The research proposes a conceptual framework to identify approaches for developing criteria for acceptable and appropriate EPIs which can be used to support and implement decision making processes by relevant organisations at the regional level. This research evaluates the application of environmental performance indicators using methodologies that assess cross-national quantitative and qualitative data and existing decision support systems. In addition, global and national indicators are examined for application and relation to the regional context. The research finds that the application of EPIs varies according to spatial scale, and is diverse among the four countries. Data availability is also identified as a major problem encountered during the development and selection of EPIs. The study finds that the governance of the existing regional body is ineffective due to differing agendas pursued by each participating country. This is because the current regional body is structured only to facilitate information exchange and cooperation in a limited manner, focusing so far only on water management issues. LMS regional goals need to be set in order to guide the stakeholders in identifying an appropriate set of EPIs. Most importantly, the research is intended to be a catalyst for encouraging the participants to integrate methods and other species of EPIs proposed in this research in their environmental assessment policies.

Parkinson’s Disease affects 10 million people worldwide, with 40% of patients developing an associated psychosis which has been identified by studies as the number one source of caretaker distress and is related to increased mortality. This is further complicated by the fact that typical antipsychotic drugs worsen many of the motor symptoms implicated in Parkinson’s Disease, with only one commercially available drug able to ameliorate both symptoms. This problem ushers the development of novel drugs to treat these symptoms, as first tested on research animals. Complicating matters, drug effectiveness on the degree of psychosis is hard to obtain in animals without a reliable biomarker. However, a hallmark of psychotic states is thought to be the reduced coordination between brain structures, through neuronal synchronization, as demonstrated by steady-state responses and is suggested to be a potential biomarker of psychosis. By building a MATLAB software we were able to analyze the degree of neural synchronization between structures, during an auditory steady-state response, in rats that had been unilaterally lesioned by the 6-Hydroxydopamine model of Parkinson’s Disease, before and after administration of the psychotomimetic drug MK801. These rats had been chronically implanted with 128-channel multi electrode array, enabling us to measure the strength of coherence between several limbic structures, associated with auditory processing, from the sampled local field potential, identifying the degree of synchronization in the animal brain. As our data demonstrate that coherence levels dropped in the psychotic drug state, for structures in both the healthy and the Parkinsonian hemisphere, we are able to further demonstrate the validity of coherence measures as a biomarker for psychosis. These results demonstrate that our software can be used as a tool to assess the therapeutic response of drugs developed, aimed at treating Parkinson’s associated psychosis. / Parkinsons sjukdom drabbar 10 miljoner världen över, där 40% av patienterna utvecklar en associerad psykos vilket har visats vara en av de största stressfaktorerna för deras vårdgivare och är även förknippat med en högre dödlighetsgrad. Denna situation förvärras av det faktum att de vanliga antipsykotiska drogerna kan förvärra många av de motoriska symptom som utgörs av Parkinsons sjukdom och det finns i dagsläget enbart en enda kommersiell drog som kan dämpa bägge symptom samtidigt. Detta problem frammanar vidare utveckling av nya läkemedel som kan behandla dessa symptom, som innebär att de först måste testas på försöksdjur. En komplikation som uppstår i relation till detta är svårigheten att utvärdera om läkemedel har någon terapeutisk effekt på de psykotiska tillstånden, enbart genom att observera försöksdjurens beteenden, och en pålitlig biomarkör krävs istället. En lösning kan dock finnas i det faktum att psykotiska tillstånd karaktäriseras av en reducerad förmåga för olika hjärnområden att koordinera genom neural synkronisering vilket demonstreras av ‘steady- state’ responser. Detta föreslår att ett mått på graden av koordineringsförmåga kan agera som en möjlig biomarkör för psykotiska tillstånd. Genom att konstruera ett MATLAB-program kunde vi analysera graden av synkronicitet mellan hjärnstrukturer, under den auditiva steady- state responsen i råttor som hade blivit ensidigt lesionerade genom 6-Hydroxiddopamin modellen av Parkinsons sjukdom, före och efter administration av den psykotomimetiska drogen MK801. Dessa råttor hade blivit kroniskt implanterade med 128 elektroder vilket möjliggjorde att vi kunde mäta styrkan i koherens i den lokala fält potentialen mellan limbiska strukturer, som är associerade med auditiv processering, vilket möjliggjorde identifiering av3dessa strukturers synkronicitet. Vår data demonstrerar att koherensen minskade under det psykotiska drogtillståndet för limbiska strukturer både i den intakta och den lesionerade hjärnhalvan. Detta är en vidare demonstration av att koherensnivåer kan agera som en biomarkör för det psykotiska tillståndet, liksom att vår mjukvara kan nyttjas som ett verktyg för att utvärdera nya läkemedels behandlingsförmåga på Parkinsons psykos.