Master of Science

thesisThis thesis describes the investigation of solvent evaporation processing of random block copolymers and its effects on morphology. Molecular dynamics simulations were performed on a coarse-grained bead spring model of a generic random block copolymer. A standard Lennard-Jones nonbonded potential and a finitely extensible nonlinear elastic (FENE) bonded potential were used. The model was first characterized without the use of solvent processing by ‘quenching' the polymer. The Lennard-Jones well depth, ?, was increased for one monomer to produce a block copolymer with blocks of different glass transition temperatures. A co-solvent was then added and the evaporation process was carried out by randomly removing solvent particles from the simulation box. The effect of the solvent evaporation process on morphology was investigated and compared to the quenched polymer. Effect of the strength of solvent, evaporation rate, and Lennard-Jones well depth were all looked at. It was concluded that quenching of random block copolymer melts under conditions where one of the blocks is glassy leads to a kinetically arrested morphology. This morphology has a smaller domain size and more extended chain conformation than the morphology when both blocks are nonglassy. Solvent evaporation processing, however, reduces these effects and produces a larger domain size

General anesthesia does not have persistent effects on attention in rodents

Background: Studies in animals have shown that general anesthesia can cause persistent spatial memory impairment, but the influence of anesthetics on other cognitive functions is unclear. This study tested whether exposure to general anesthesia without surgery caused a persistent deficit in attention in rodents.Methods: To evaluate whether anesthesia has persistent effects on attention, rats were randomized to three groups. Group A was exposed for 2 h to isoflurane anesthesia, and tested the following seven days for attentional deficits. Group B was used as a control and received room air before attentional testing. Since there is some evidence that a subanesthetic dose of ketamine can improve cognition and reduce disorders of attention after surgery, rats in group C were exposed to isoflurane anesthesia in combination with a ketamine injection before cognitive assessment. Attention was measured in rats using the 5-Choice Serial Reaction Time Task, for which animals were trained to respond with a nose poke on a touchscreen to a brief, unpredictable visual stimulus in one of five possible grid locations to receive a food reward. Attention was analyzed as % accuracy, % omission, and premature responses.Results: Evaluating acute attention by comparing baseline values with data from the day after intervention did not reveal any differences in attentional measurements. No significant differences were seen in % accuracy, % omission, and premature responses for the three groups tested for 7 consecutive days.Conclusion: These data in healthy rodents suggest that general anesthesia without surgery has no persistent effect on attention and the addition of ketamine does not alter the outcome

Three Decades in the Cold and Wet: A Career in Northern Archaeology

Thomas H. McGovern has been a pioneering researcher in the North Atlantic region for most of the past 40 years. He has taken his specialty in zooarchaeology beyond counting bones to actually addressing questions about human environment interactions and human response to extreme environmental events. A prolific writer and researcher with a multitude of publications and an impressive funding record, McGovern has always been a proponent of multidisciplinarity and international collaboration. His vision resulted in the creation of the North Atlantic Biocultural Organization (NABO) that currently has more than 400 scientific partners and has been leading projects throughout the Circum Atlantic for over 25 years. The interconnectivity of regions and global events has always been the key to his research, and as of last year, with support from the National Science Foundation Office of Polar Programs, it resulted in the creation of the Global Human Ecodynamics Alliance (GHEA) that is now taking interdisciplinarity and international collaboration to a global perspective

Addressing environmental and atmospheric challenges for capturing high-precision thermal infrared data in the field of astro-ecology

Using thermal infrared detectors mounted on drones, and applying techniques from astrophysics, we hope to support the field of conservation ecology by creating an automated pipeline for the detection and identification of certain endangered species and poachers from thermal infrared data. We test part of our system by attempting to detect simulated poachers in the field. Whilst we find that we can detect humans hiding in the field in some types of terrain, we also find several environmental factors that prevent accurate detection, such as ambient heat from the ground, absorption of infrared emission by the atmosphere, obscuring vegetation and spurious sources from the terrain. We discuss the effect of these issues, and potential solutions which will be required for our future vision for a fully automated drone-based global conservation monitoring system.Comment: Published in Proceedings of SPIE Astronomical Telescopes and Instrumentation 2018. 8 pages, 3 figure

Faunal Analysis of the Early Modern Bishop\u27s Farm at Skalholt, Arnessysla Iceland

This dissertation presents the analysis of faunal material recovered from middens outside the main complex of the Bishop of Southern Iceland\u27s Cathedral farm at Skáholt, Arnessysla, Iceland. Issues of diet, deposition patterns, as well as participation in larger trade and intellectual networks addressed. All of these issues are examined in order to investigate larger issues centered around the early modern Atlantic world. The Skáholt material is also compared with the larger body of existing early modern Icelandic archaeofaunal data in order to investigate issues of adaptation and resilience in the face of harsh climatic as well as social and economic conditions

Diagrama de manejo da densidade para Araucaria angustifolia (Bert.) o. Ktze.

Orientador : Prof. Dr. Nelson Carlos RosotCoorientador : Prof. Dr. Julio Eduardo ArceCoorientador : Prof. Dr. Cesar Augusto Guimarães FingerDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Engenharia Florestal. Defesa: Curitiba, 25/02/2013Bibliografia: f. 67-71Área de concentração : Manejo FlorestalResumo: O diagrama de manejo da densidade (DMD) permite encontrar a máxima produtividade em área basal e volume de um povoamento florestal, a partir de diferentes espaçamentos iniciais e densidades, indicando os momentos de intervenções de desbastes, evitando a mortalidade das árvores por concorrência e consequentes prejuízos econômicos. Neste sentido, o objetivo deste estudo foi determinar um diagrama de manejo da densidade para Araucaria angustifolia (Bert.) O. Ktze a partir do modelo de Tang et al. (1994). Foram utilizados dados provenientes de Misiones na Argentina para a construção do DMD; e dados da empresa Araupel, da Estação Experimental de Rio Negro e da Floresta Nacional de Irati foram empregados para a validação do DMD. O modelo de Tang et al.(1994) foi selecionado devido a sua fácil aplicabilidade, e assim ajustado no espaçamento 1,5 x 1,5 m para a construção do DMD e espaçamentos 1,5 x 2,0m, 2,0 x 2,0m; 2,0 x 2,5m; 2,5 x 2,5m; 2,5 x 3,0m; 3,0 x,3,0m, 3,5 x 3,5m e 4,0 x 4,0m afim de verificar o comportamento deste modelo em diferentes situações de densidade. A partir da equação foram estimadas densidades para diâmetros médios quadráticos entre 4 e 46 cm em espaçamentos 1,5 m²; 2,5 m²; 4,0 m²; 6,0 m² e 9,0 m², modificando apenas as variáveis independentes número de árvores potencial por hectare e diâmetro médio quadrático no tempo t. Utilizando o mesmo modelo foram gerados o gráfico de autodesbaste, as zonas de concorrência, e Índices de Densidade do Povoamento (IDP) adotando um diâmetro médio quadrático padrão de 25 cm. Para obter o diagrama de manejo da densidade utilizando o volume como variável dependente, foi selecionado o melhor entre cinco modelos. Foi possível construir o diagrama de manejo da densidade com os dados de Misiones na Argentina para área basal e volume e validá-lo com os povoamentos Araucaria angustifolia em situações extremas de manejo, confirmando sua aplicabilidade para qualquer plantio homogêneo desta espécie. Além disso, foi verificado que os plantios mais adensados entram primeiro na zona de concorrência que os plantios com maiores espaçamentos.Abstract: The density management diagram (DMD) allows finding the maximum productivity in basal area and volume of a forest stand from different initial spacings and densities, indicating the moments of thinning avoiding tree mortality by competition and consequent economics losses. Therefore the objective of this study was to build a density management diagram for Araucaria angustifolia (Bert.) O. Ktze from Tang et al. (1994) model. Data from Misiones (Argentina) were used for the DMD construction, and data from Araupel Company, Experimental Station of Rio Negro, and Irati National Forest were used to validate the DMD. The Tang et al. (1994) model was selected due to its easy application and thus adjusted in the density 1.5 x 1.5m for the density management diagram construction and the densities 1.5 x 2.0m, 2.0 x 2.0m; 2.0 x 2.5m; 2.5 x 2.5m; 2.5 x 3.0m; 3.0 x 3.0m, 3.5 x 3.5m and 4.0 x 4.0m in order to verify the behavior of this model in different density situations. From the density equations were estimated for quadratic mean diameters between 4 and 46 cm on spacing at 1.5 m²; 2.5 m²; 4.0 m²; 6.0 m² and 9.0 m², changing only the independent variables potential tree number per hectare and mean square diameter at time t. With the same model, the self thinning graphic zones of competition and Stand Density Indices (IDP) were generated, adopting a standard quadratic mean diameter of 25 cm. To obtain the density management diagram using volume as a dependent variable, the best among five models was selected. It was possible to construct the density management diagram with data from Misiones (Argentina) for basal area and volume and validate it with Araucaria angustifolia stands in extreme situations of management, confirming its applicability to any homogeneous planting of this species. Furthermore, it was found that denser initial spacing regimes come first in the competition zone then plantations with larger spacings

Stem cell-mediated osteogenesis: therapeutic potential for bone tissue engineering

Intervertebral disc degeneration often requires bony spinal fusion for long-term relief. Current arthrodesis procedures use bone grafts from autogenous bone, allogenic backed bone, or synthetic materials. Autogenous bone grafts can result in donor site morbidity and pain at the donor site, while allogenic backed bone and synthetic materials have variable effectiveness. Given these limitations, researchers have focused on new treatments that will allow for safe and successful bone repair and regeneration. Mesenchymal stem cells have received attention for their ability to differentiate into osteoblasts, cells that synthesize new bone. With the recent advances in scaffold and biomaterial technology as well as stem cell manipulation and transplantation, stem cells and their scaffolds are uniquely positioned to bring about significant improvements in the treatment and outcomes of spinal fusion and other injuries

Redes neurais artificiais e modelos de regressão para estimação de variáveis dendrométricas em Pinus taeda L : análise comparativa

Orientador : Prof. Dr. Carlos Roberto SanquettaCoorientadores : Prof. Dr. Renato Vinicius Oliveira Castro, Prof. Dr. Julio Eduardo ArceTese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Engenharia Florestal. Defesa: Curitiba, 19/12/2016Inclui referências: f. 142-153Resumo: Estudos com Redes Neurais Artificiais (RNA) para o gênero Pinus são incipientes no Brasil. O objetivo deste trabalho foi testar as RNA para estimação da altura, volume e afilamento para povoamentos de Pinus taeda L., bem como avaliar sua aplicabilidade e compará-la com os métodos tradicionais de regressão. Para a estimação de altura por regressão e RNA foram utilizados dados de 304 parcelas permanentes, totalizando 2.454 remedições de parcela em plantios de Pinus taeda L. entre 3 e 21 anos, pertencentes à empresa Klabin S.A. No ajuste dos modelos hipsométricos os dados foram estratificados em ano de plantio, totalizando 11 estratos. Para cada estrato foram ajustados 4 modelos hipsométricos, e esses avaliados de acordo com o coeficiente de correlação ajustado (R² ajust), erro padrão da estimativa (Syx%), gráficos de dispersão de resíduos, além de estatísticas complementares como viés (V), média das diferenças absolutas (MD) e desvio padrão das diferenças (DPD). Os melhores modelos aplicados nos dados de validação foram comparados às RNA, que por sua vez foram treinadas no software Statistica 7.0, em que as 20 melhores redes foram aplicadas aos dados sem estratificação. A RNA com melhor desempenho para estimar a altura total foi comparada com o modelo de regressão por estrato. Para avaliar a precisão dos modelos hipsométricos e RNA para a redução da medição das alturas, os dados de ajuste foram reduzidos em 30% e 60%, e ajustados e treinados respectivamente. Para a estimação de volume total com casca e diâmetros e volumes ao longo do fuste e ainda volume total com casca por meio de funções de afilamento, foram utilizadas 212 cubagens de árvores com diâmetro a 1,30 (dap) entre 5 e 45 cm e aplicados o método da RNA e regressão. Na metodologia de ajuste por regressão os dados foram divididos em 4 estratos e para cada estrato ajustado 4 modelos de volume e 4 modelos de afilamento. O treinamento das RNA e seleção dos modelos de regressão foram realizados com a mesma metodologia da relação hipsométrica. As melhores RNA e modelos de regressão aplicados aos dados de validação foram comparados para verificar as melhores estimativas. Na estimativa de altura, modelos de regressão apresentaram melhor desempenho que as RNA para a base de dados total e na redução de até 60%. Na estimativa de volume total com casca os modelos estratificados por regressão apresentaram resultados mais satisfatórios, enquanto na estimativa do diâmetro e volume ao longo do fuste as RNA foram mais precisas. Conclui-se que, para as estimativas de altura e volume total de Pinus taeda, o uso de modelos de regressão é mais adequado especialmente em função da maior facilidade de aplicação. Já para as estimativas de diâmetros e volumes ao longo do fuste, o uso das RNA é mais adequado em razão de sua maior precisão e maior complexidade de ajuste dos modelos de afilamento. Palavras-chave: desempenho, interações não lineares, modelos de regressão.Abstract: Studies with Artificial Neural Networks (ANN) for the genus Pinus are incipient in Brazil. The main purpose of this work was to test ANN for height, volume and taper estimation for stands of Pinus taeda L., as well as to evaluate its applicability and to compare it with traditional regression methods. For the height estimation by regression and ANN, data from 304 permanent plots were used, totaling 2,454 remeasurements in Pinus taeda L plantations between 3 and 21 years, belonging to the company Klabin S.A. For the hypsometric models the data were stratified in year of planting, totaling 11 strata. For each stratum, 4 hypsometric models were fitted, and these were evaluated according to the adjusted correlation coefficient (R² adjust), standard error of estimative (Syx%), residual scatter plots, as well as complementary statistics, such as bias (V), absolute differences (MD) and standard deviation of differences (DPD). The best models applied in the validation data were compared to ANN trained in the Statistica 7.0 software, in which the 20 best networks were applied to the data without stratification. The best ANN performing to estimate total height was compared with the stratum regression model. To evaluate the accuracy of the hypsometric and ANN models for the height measurements reduction, the data were reduced by 30% and 60%, and adjusted and trained, respectively. For the estimation of the total volume with bark and diameters and volumes along the stem and also total volume with bark by means of tapering functions, 212 trees were scaled with diameter at 1.30 (dbh) between 5 and 45 cm and ANN and regression method was applied. In the regression adjustment method the data were divided into 4 strata and for each stratum adjusted 4 volume models and 4 taper models. The ANN training and regression models selection were performed using the same methodology as the hypsometric relation. The best ANN and regression models applied to the validation data were compared to verify the best estimates. In height estimation, regression models presented better performance than ANN for the total database and data reduction of up to 60%. For the estimation of total volume with bark, the models stratified by regression presented more satisfactory results, whereas for the estimation of diameter and volume along the stem the ANN was more accurate. It was concluded that, for the estimates of height and total volume of Pinus taeda, the use of regression models is more appropriate especially due to the greater ease of application. For the estimation of diameters and volumes along the stem, the use of ANN is more adequate because of the better precision and greater complexity of adjustment of the models of tapering. Keywords: Performance, nonlinear interactions, regression models

Abraham Lincoln, his spirit lives : an appreciation

This edition is limited to 300 copies. Includes port. of Lincoln engraved by H. Gugler after a painting by J.H. Littlefield. The cover includes a small shadow illustration of Lincoln standing in front of a chair with his name above the chair.https://scholarsjunction.msstate.edu/fvw-pamphlets/2071/thumbnail.jp