Thesis (Ph. D.)--University of Canterbury, 2009. / Typescript (photocopy). Includes bibliographical references (p. 214-243). Also available via the World Wide Web.

Nicotine and stimulant medications share similar neurotransmission-related effects in the pre-frontal cortex, but it is unclear if nicotine has a similar benefit on inhibitory control. Impulsivity resulting from deficits in inhibition and sustained attention have been posited as a unifying mechanism of adult ADHD psychopathology. These deficits were quantified in the present study using Go/No-Go task accuracy and intra-individual reaction time variability (RTV). The electro-cortical P3a amplitude indexes inhibitory cognitive processes and sustained attention-related frontal cortex activation in response to infrequent NOGO stimuli. However, little work has characterized the effects of nicotine on P3a or RTV in adult ADHD. Therefore, the effects of the nicotine patch on NOGO P3a amplitude, inhibitory accuracy, and RTV were assessed in non-medicated ADHD adults (12 smokers, 12 never-smokers) in a double-blind, placebo-controlled, repeated-measures design. Nicotine patch, relative to placebo patch, significantly increased NOGO inhibitory accuracy, significantly decreased GO RTV, and significantly increased NOGO P3a peak amplitude at four frontal electrode sites. These results suggest that the nicotine reduces impulsivity in adults with ADHD. The implications of these basic findings to the clinical assessment and treatment of ADHD are discussed. Additional reports at both the basic and clinical levels are needed to confirm and extend these findings.

Bones have a large intrinsic capacity for repair and regeneration following an injury, however, an estimated 5-10% of nearly 8 million fractures that occur every year in the United States lead to nonunions. The process of bone regeneration is a complex trait that brings together different complements of molecular and cellular interactions to carry out its necessary mechanical functions. These interactions may be attributable to the effects of genetic variations that contribute to differences in bone morphology and fracture healing. This study was undertaken to determine how genetic variability that controls phenotypic qualities of bone affect rates and patterns of fracture healing. Three inbred strains of mice (A/J (AJ), C57BL/6J (B6), and C3H/HeJ (C3)) with known structural and biomechanical differences resulting from fetal bone development were examined. Transverse fractures were generated in the femur and healing traits were evaluated using quantitative real-time polymerase chain reaction (qRT-PCR), micro-computed tomography (μCT), biomechanical torsional testing, and cartilage contrast-enhanced micro-computed tomography (CECT). The temporal analysis of gene expression revealed that B6 had the longest duration of chondrocyte maturation and the greatest relative expression of osteogenic genes relative to either C3 or AJ. While AJ and C3 exhibited similar patterns of chondrogenesis, AJ initiated osteogenesis earlier than C3. These results suggest that compared to either AJ or B6, the C3 strain exhibited the least temporal coordination between the chondrogenic and osteogenic stages. Consistent with the relative patterns of RNA expression, μCT evaluations at day 21 post fracture showed that B6 had higher callus mineralization than AJ and C3. μCT, cartilage CECT, and biomechanical testing revealed less tissue mineralization and more cartilage near the fracture gap, which indicated a less developed bony bridge in C3 calluses at day 21 post fracture. The lack of large amounts of cartilage in calluses of all strains by day 21 indicated that all strains had initiated osteogenesis by this time. Taken together, these results showed that mice with different genetic backgrounds express different patterns of mobilization and renewal of skeletal stem cells with differing temporal progressions of chondrogenic and osteogenic differentiation. These data further show that these variations affect the phenotypic properties of fracture calluses during the process of fracture healing.

It has been shown in previous studies that persons with aphasia (PWA) exhibit deficits in cognitive skills, despite the traditional definition of aphasia as an impairment specifically in language processing. This project provides an in-depth look into one of these cognitive processes: attention. This project views attention from a domain-general perspective and is particularly focused on looking at intra-individual variability (IIV) in attention over time. We begin by presenting a schema of attention and language in aphasia, followed by the results of two experiments that examine the effect of task demands on attention processing, including IIV in performance. The first experiment focuses on the effect of task demands on between-session IIV (BS-IIV) in attention, as well as on group differences between PWA and controls, using purely non-linguistic tasks. Results suggest that PWA exhibit overall higher degrees of BS-IIV in domain-general, attention than do controls. Results also suggest that increased task demands elicit increased BS-IIV in attention in PWA, but not in controls. The second experiment examines the effects of task demands on BS-IIV as well as on within-session IIV (WS-IIV) in attention, as well as group differences between PWA and controls, using both linguistic and non linguistic tasks. Results of this experiment suggest that PWA and controls exhibit similar levels of BS-IIV, but that PWA exhibit higher levels of WS-IIV than do controls. Additionally, both groups show an effect of task demands on both BS-IIV and WS-IIV, such that higher task demands elicit higher levels of both types of IIV. Results also suggest that levels of BS-IIV and WS-IIV may rise even further for PWA when language demands are added to a task. Together, the results of these experiments suggest that PWA experience higher degrees of IIV than controls, and that higher task demands, including the addition of language tasks, increase PWA levels of IIV even more. These findings may have important implications for understanding attention during language therapy, as therapy sessions involve complex demands and require consistent attention over time. Future research should directly examine the relationship between IIV in attention and treatment outcomes in PWA.

AN ABSTRACT OF THE THESIS OF DAGONG RAN, for the MASTER OF ARTS degree in PSYCHOLOGY, presented on JULY 5, 2016, at Southern Illinois University Carbondale. TITLE: HEART RATE VARIABILITY IN CHILDREN: TONIC CHARACTERISTICS AND REACTIVITY MAJOR PROFESSOR: Dr. Sarah Kertz This study investigated tonic heart rate variability (HRV) and heart rate variability reactivity in response to stress in children with anxiety and worry symptoms. Twenty-nine children age 8 to 12 from a rural Midwestern region completed the study and were included in the data analyses. Participants completed an artificial auditioning task in which they were asked to sing in front of a video camera. Electrocardiogram were recorded prior, during, and after the task. Frequency and time domain analyses of HRV were conducted. Neither parent-report or child self-report anxiety/worry symptom levels were associated with baseline frequency domain and time domain HRV. All participants showed similar HRV reactivity in response to the stress task. Specifically, high frequency HRV was higher during baseline than during stress task, and low frequency HRV was higher during baseline than both during stress task and recovery. These findings contradicted with previous literature results. More studies are needed to examine the association between anxiety and HRV in children.

Circuitos integrados VLSI (Very Large Scale Integration) usando nanotecnologia demandam novos materiais, estruturas, metodologias de projeto e ferramentas de CAD para lidar com os problemas decorrentes do processo de fabricação, tais como variabilidade. Alguns tipos de concepção são mais ou menos robustos às variações de processo ou ambientais, quer sistemáticas ou aleatórias. Esta pesquisa avalia os tipos de projeto de circuitos integrados e os aspectos que podem ajudar a melhorar a capacidade de fabricação e desempenho nas futuras gerações de dispositivos. Neste contexto, é fundamental avaliar como será o comportamento da tecnologia FinFET em tecnologias além de 20nm. A tecnologia FinFET é candidata a substituir a tecnologia CMOS planar no processo de fabricação. Obter informações preditivas sobre o comportamento desta tecnologia no projeto de células é importante tanto para projetistas como para desenvolvedores de ferramentas de EDA. Esta tese explora tipos de projeto de células básicas com tecnologia FinFET. São objetivos principais a caracterização do desempenho temporal e potência, tanto dinâmica como estática, assim como a identificação dos principais parâmetros geométricos em tecnologias FinFET cuja variabilidade afete as características elétricas e a avaliação da robustez destas células aos efeitos de variabilidade de processo. A primeira contribuição deste trabalho é a exploração de tipos de projeto possíveis com a tecnologia FinFET, tais como o projeto com FinFET de 4 terminais nos estilos Short-Gate, Independent-Gate e Low-Power. Estas células foram caracterizadas e modeladas de forma a serem inseridas em um fluxo de síntese regular e comparadas com células em tecnologia bulk CMOS. A segunda contribuição deste trabalho é a identificação das principais fontes de variabilidade e a tendência de comportamento em tecnologias FinFET sub-20nm. Até o momento da elaboração deste documento, a pesquisa de estado-da-arte aponta que este foi o primeiro trabalho a investigar em nível elétrico o impacto da variabilidade em parâmetros geométricos e elétricos na potência dinâmica e estática de dispositivos FinFET sub-20nm. Finalmente, a terceira contribuição deste trabalho é quantificar a influência das flutuações da função trabalho do metal de gate em FinFETs nas tecnologias sub-20nm, traçando um panorama preditivo dos efeitos da variabilidade em tecnologias sub-20nm. / Integrated circuits VLSI (Very Large Scale Integration) using nanotechnology require new materials, structures, design methodologies and CAD tools to address the problems caused by the manufacturing process, such as variability. Some design types are more or less robust to process variations or environmental either systematic or random. This research evaluates the types and aspects of integrated circuit designs that can help to improve manufacturing capacity and performance in future generations. In this context, it is essential to assess what will be the behavior of FinFET technology technologies beyond 20nm. The FinFET technology is a candidate to replace the planar CMOS technology in the manufacturing process. To obtain predictive information about the behavior of this technology in cell design is important for both designers and developers of EDA tools. This work explores basic types of cell design with FinFET technology. Main objectives are to characterize timing and power, both dynamic and static, as well as the identification of the main geometrical parameters in FinFET technologies whose variability affects the electrical characteristics and evaluate the robustness of these cells to process variability effects. The first contribution of this work is the exploration of possible project types with FinFET technology, such as FinFET design with 4 terminals in styles Short-Gate, Independent-Gate and Low-Power. These cells were characterized and modeled in order to be inserted into one regular synthesis flow and compared with cells in bulk CMOS technology. The second contribution of this work is to identify the main sources of variability and the pattern of behavior in FinFET technology sub-20nm. By the time of this writing, the state of the art research shows that this is the first study to investigate in electrical level the variability impact of electrical and geometrical parameters in the dynamic and static power of FinFET devices sub-20nm. The third contribution of this work is to quantify the influence of metal gate workfunction fluctuations of FinFETs in sub-20nm technologies, tracing a predictive picture of the effects of variability in sub-20nm technologies.

In manufacturing, automation has replaced many dangerous, mundane, arduous and routine manual operations, for example, transportation of heavy parts, stamping of large parts, repetitive welding and bolt fastening. However, skilled operators still carry out critical manual processes in various industries such as aerospace, automotive and heavy-machinery. As automation technology progresses through more flexible and intelligent systems, the potential for these processes to be automated increases. However, the decision to undertake automation is a complex one, involving consideration of many factors such as return of investment, health and safety, life cycle impact, competitive advantage, and resources and technology availability. A key challenge to manufacturing automation is the ability to adapt to process variability. In manufacturing processes, human operators apply their skills to adapt to variability, in order to meet the product and process specifications or requirements. This thesis is focussed on understanding the 'variability involved in these manual processes, and how it may influence the automation solution'. Two manual industrial processes in polishing and de-burring of high-value components were observed to evaluate the extent of the variability and how the operators applied their skills to overcome it. Based on the findings from the literature and process studies, a framework was developed to categorise variability in manual manufacturing processes and to suggest a level of automation for the tasks in the processes, based on scores and weights given to the parameters by the user. The novelty of this research lies in the creation of a framework to categorise and evaluate process variability, suggesting an appropriate level of automation. The framework uses five attributes of processes; inputs, outputs, strategy, time and requirements and twelve parameters (quantity, range or interval of variability, interdependency, diversification, number of alternatives, number of actions, patterned actions, concurrency, time restriction, sensorial domain, cognitive requisite and physical requisites) to evaluate variability inherent in the process. The level of automation suggested is obtained through a system of scores and weights for each parameter. The weights were calculated using Analytical Hierarchical Process (AHP) with the help of three experts in manufacturing processes. Finally, this framework was validated through its application to two processes consisting of a lab-based peg-in-a-hole manual process and an industrial process on welding. In addition, the framework was further applied to three processes (two industrial processes and one process simulated in the laboratory) by two subjects for each process to verify the consistency of the results obtained. The results suggest that the framework is robust when applied by different subjects, presenting high similarity in outputs. Moreover, the framework was found to be effective when characterising variability present in the processes where it was applied. The framework was developed and tested in manufacturing of high value components, with high potential to be applied to processes in other industries, for instance, automotive, heavy machinery, pharmaceutical or electronic components, although this would need further investigation. Thus, future work would include the application of the framework in processes in other industries, hence enhancing its robustness and widening its scope of applicability. Additionally, a database would be created to assess the correlation between process variability and the level of automation.

Neurons and networks of the brain may use various strategies of computation to provide the neural substrate for sensation, perception, or cognition. To simplify the scenario, two of the most commonly cited neural codes are firing rate and temporal coding, whereby firing rates are typically measured over a longer duration of time (i.e., seconds or minutes), and temporal codes use shorter time windows (i.e., 1 to 100 ms). However, it is possible that neurons may use other strategies. Here, we highlight three methods of computation that neurons, or networks, of the brain may use to encode and/or decode incoming activity. First, we explain how single neurons of the brain can utilize a neuronal oscillation, specifically by employing a ‘spike-phase’ code wherein responses to stimuli have greater reliability, in turn increasing the ability to discriminate between stimuli. Our focus was to explore the limitations of spike-phase coding, including the assumptions of low firing rates and precise timing of action potentials. Second, we examined the ability of single neurons to track the onset of network bursting activity, namely ‘burst predictors’. In addition, we show that burst predictors were less susceptible to an in vitro model of neuronal stroke (i.e., excitotoxicity). Third, we discuss the possibility of distributed processing with neuronal networks of the brain. Specifically, we show experimental and computational evidence supporting the possibility that the population activity of cortical networks may be useful to downstream classification. Furthermore, we show that when network activity is highly variable across time, there is an increase in the ability to linearly separate the spiking activity of various networks. Overall, we use the results of both experimental and computational methods to highlight three strategies of computation that neurons and networks of the brain may employ.

Resumo: O objetivo deste trabalho foi analisar as variabilidades espacial, sazonal e interanual da precipitação pluviométrica nas regiões Sudeste e Sul do Brasil. Foram utilizadas 164 séries mensais e anuais de chuvas para o período de 1972 a 2002 e dados de médias mensais de radiação de ondas longas emergentes (ROLE), para o período de junho de 1974 a dezembro de 2002, com pontos de grade com resolução espacial de 2,5º x 2,5º, entre as latitudes 20ºN e 35ºS e longitudes entre 0º; 90ºW. A partir das análises de agrupamento, de componentes principais e geoestatística foram identificadas 13 regiões homogêneas de regime de precipitação. A precipitação anual variou de 956 mm nos vales do São Francisco- Jequitinhonha a 1830 mm na Bacia do Iguaçu-Chapecó. As três primeiras componentes principais (CP) da matriz de médias mensais de precipitação explicam conjuntamente, 61,49% da variância. A primeira CP representa o campo médio de precipitação, a segunda CP representa o período de verão e a terceira CP apresenta dois pontos extremos: o mês de novembro e o mês de fevereiro. Através dos dados de ROLE analisou-se a influência da Zona de Convergência do Atlântico Sul (ZCAS) na precipitação. As três primeiras componentes principais da matriz de médias mensais de ROLE explicam conjuntamente 96,27% da variância. A primeira CP representa a convecção média. A segunda CP representa o período de primavera e a terceira CP representa o período de verão. As correlações, significativas ao nível de 5%, obtidas entre os autovetores das matrizes de precipitação pluviométrica e de ROLE, corroboram a influência da ZCAS no regime de precipitação das regiões Sudeste e Sul do Brasil. / Abstract: The spatial, seasonal and interannual variability of rainfall in Southeastern and Southern Brazil were analyzed. For that, 164 series of rainfall for the period of 1972 to 2002 and data about outgoing longwave radiation (OLR) for the period of 1974 to 2002 were utilized. From the clusters analysis and components analysis (PCA), 13 homogeneous regions under precipitation regime were identified. The annual rainfall varied from 956 mm in São Francisco-Jequitinhonha valleys to 1830 mm in Iguaçu-Chapecó basin. The three first matrix principal components (PC) of monthly average rainfall (average of 30 years) explain together 61.49% of the variance. The first PC represents the mean rainfall field, the second PC represents the extended rainy period (September to May) and the third PC presents two extreme points: November indicates the end of spring and the beginning of summer; and February indicates the end of summer and the beginning of autumn. The OLR influence on the rainfall variability in the Southeast and in the South was also evaluated. Through the PCA, the behavior of the South Atlantic Convergence Zone (SACZ) was studied together with its influence on the rainfall variability. The three first matrix main components of OLR monthly average (average of 30 years) explain together 96.27% of the variance. The first main component (CP) is associated to the period of autumn. The second PC represents the winter/summer period, and the third PC represents summertime. The correlations, significative to the level of 5%, obtained between the rainfall and OLR eigenvectors, attest their influence on the rainfall regime in Southeastern and Southern Brazil. / Orientador: Luzia Aparecida Trinca / Coorientador: Jonas Teixeira Nery / Banca: Angelo Cataneo / Banca: João Francisco Escobedo / Banca: Shigetoshi Sugahara / Banca: Paulo Henrique Caramori / Doutor

Submitted by BRUNO NOGUEIRA DE OLIVEIRA LIMA null (limanogueirabruno@hotmail.com) on 2017-06-19T15:53:30Z No. of bitstreams: 1 Diss_Bruno_Nogueira_de_Oliveira_Lima.pdf: 928712 bytes, checksum: f772bde0ef17c470822f47584ca868ec (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-06-21T13:07:39Z (GMT) No. of bitstreams: 1 lima_bno_me_jabo.pdf: 928712 bytes, checksum: f772bde0ef17c470822f47584ca868ec (MD5) / Made available in DSpace on 2017-06-21T13:07:39Z (GMT). No. of bitstreams: 1 lima_bno_me_jabo.pdf: 928712 bytes, checksum: f772bde0ef17c470822f47584ca868ec (MD5) Previous issue date: 2017-05-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Em todos os esportes equestres é comum que os animais sejam testados com grande variação de obstáculos, percursos e ambientes. Essas dificuldades impostas nas provas equestres justificam o foco em um dos aspectos mais importantes do temperamento dos cavalos: sua reatividade ou comportamento de fuga ("flightness"). A reatividade dos potro pode ser caracterizada pela aproximação ou fuga de determinado estímulo. Este estudo teve como objetivo verificar a existência da variabilidade na expressão do comportamento de um grupo de potros Brasileiro de Hipismo (BH) frente à novo objeto e se existe alguma associação entre a reatividade dos animais durante o teste do novo objeto e a presença do polimorfismo de nucleotídeo único (SNP - Single Nucleotide Polymorphism) A758T do gene DBH. O teste do novo objeto (feito com a utilização de um guarda-chuva aberto) foi realizado em 260 potros Brasileiro de Hipismo (BH) sem nenhum treinamento montado. A avaliação da reatividade e rapidez de habituação foi feita por avaliação qualitativa do comportamento (QBA - Qualitative Behavior Analysis) durante o teste de novo objeto. Foi possível observar grande variabilidade fenotípica entre os potros, sendo que os animais foram divididos em um grupo com altos valores para as variáveis RELAXADO, FOCADO, CONFIANTE e POSITIVAMENTE CURIOSO e outro grupo de animais com altos valores para PRECAVIDO, AGITADO, CONFUSO e DESESPERADO. Também foi observado que os criatórios diferiram entre si quanto à adoção de seleção direcional ou não para a reatividade dos animais. Apesar disso, a presença de animais que podem ser caracterizados como "patologicamente ansiosos", evidencia a necessidade de maior atenção por parte dos criatórios nacionais na seleção de animais com menor reatividade. O nosso estudo evidenciou também que a SNP A758T no gene DBH não estava presente no subgrupo de 20 animais genotipados dentro da população estudada. Esse subgrupo de 20 animais genotipados era não aparentado e possuía fenótipo representativo da população, portanto, desestimula pesquisas futuras com a SNP A758T na raça BH. / In all the equestrian sports it is common that the animals are tested with a great variation of obstacles, courses and environments. These difficulties imposed in the equestrian sports justify the focus in one of the aspects of a horse's temperament: his reactivity or flight behavior (“flightiness”). The horse's reactivity can be characterized by his approach or escape of determined stimulus. This study aimed to verify the existence of behavior variability in Brazilian Sport Horse fillies and colts and if there is any association between that behavior and the presence of the DBH SNP A758T. In order to accomplish this, we tested 260 Brazilian Sport Horse fillies and colts, without any mounted training, in a novel object test using an umbrella. The horse’s reactivity and habituation speed was analyzed through a QBA- Qualitative Behavior Analysis during the novel object test. It was possible to observe a great phenotypic variability between the animals and divide them in a group with high values for the variables RELAXED, FOCUSED, CONFIDENT and POSITIVELY CURIOUS and another group of animals with high values for CAUTIOUS, AGITATED, CONFUSED and DESPAIRED. We also observed that the breeders differed with respect to the adoption of a directional selection or not for the animals' reactivity. In spite of this, the presence of animals that can be characterized as "pathologically anxious", shows the need for a greater attention on the part of national breeders in the selection of animals with less reactivity. Moreover, our study also showed that SNP A758T in the DBH gene was not present in a subgroup of 20 animals within the study population. This subgroup of 20 genotyped animals were unrelated and had a phenotype representative of the population, therefore discourages future research with SNP A758T in Brazilian Sport Horses.