1,908 research outputs found
Giving in Minnesota, 2010 Edition
The Minnesota Council on Foundations has produced its Giving in Minnesota, 2010 Edition research report, the most comprehensive analysis of charitable giving in the state. The 2010 edition features Minnesota giving in 2008, the most recent year for which comprehensive data are available. This report includes information about overall giving by foundations, corporations and individuals in Minnesota, along with detailed grantmaking trends by the Giving in Minnesota sample, which is comprised of 100 of the state's largest grantmakers based on grants paid
Global function approach in structural analysis: Basic approach, numerical results
The structural response to a given environment is described by the differential equations of motion of deformable bodies. Analytic solutions of such problems for a reasonably large class of structural configurations are not within the realm of the possible. Consequently, the mathematical problem is recast into a numerical problem for solution on the computer. New technology in the space and energy fields led to a growing demand for accurate analysis which at times cannot be met due to the limits set by available budgets for computer time. In response to this need for more efficient numerical analysis, the possibilities of reducing the number of freedoms in the system through a revival of the global function approach were explored
Scanning Electron Microscopy for Nano-morphology Characterisation of Complex Hierarchical Polymer Structures
This thesis presents novel and innovative ways of imaging and analysing natural hierarchical polymers using low-voltage scanning electron microscopy and secondary electron energies. Materials such as plant fibres, feathers and silk, have received increased societal and scientific interest recently, while the plastic industry is faced with growing public concerns over its generation of waste, and use of petrochemical precursors. In nature, materials are produced sustainably and they furthermore exhibit inspiring mechanical performance. One such material is spider silk, which is spun at room temperature from a water-based protein gel to form a thread, which even with diameters as small as 5 μm easily suspends the weight of a palm-sized spider. It is known that the secret to spider silk’s remarkable properties lies within its nanoscale structures. However, the direct observation of these nanostructures has remained difficult due to their small size and their sensitivity to chemical and mechanical alteration. This work presents novel sample preparation protocols and demonstrates their use in accessing size and location information of key nanostructures within spider silk through nanoscale observation in the scanning electron microscope. As the secondary electron spectroscopy technique employed here is relatively new, new workflows from sample preparation, over optimal imaging and spectral acquisition and novel multivariate data analysis techniques are innovated and described in detail. The rigorous consideration of the material and method are exemplified on a feather section, to show that the secondary electron energy signal in the scanning electron microscope may generate molecular composition maps on a proteinaceous structural polymer. This work lays out all requirements for unlocking the vast potential for nanoscale chemical mapping which lies in the nanoscale secondary electron signal, to further inspire ground-breaking studies into the nanostructures of complex hierarchical polymers
Single exponential decay waveform; a synergistic combination of electroporation and electrolysis (E2) for tissue ablation.
BackgroundElectrolytic ablation and electroporation based ablation are minimally invasive, non-thermal surgical technologies that employ electrical currents and electric fields to ablate undesirable cells in a volume of tissue. In this study, we explore the attributes of a new tissue ablation technology that simultaneously delivers a synergistic combination of electroporation and electrolysis (E2).MethodA new device that delivers a controlled dose of electroporation field and electrolysis currents in the form of a single exponential decay waveform (EDW) was applied to the pig liver, and the effect of various parameters on the extent of tissue ablation was examined with histology.ResultsHistological analysis shows that E2 delivered as EDW can produce tissue ablation in volumes of clinical significance, using electrical and temporal parameters which, if used in electroporation or electrolysis separately, cannot ablate the tissue.DiscussionThe E2 combination has advantages over the three basic technologies of non-thermal ablation: electrolytic ablation, electrochemical ablation (reversible electroporation with injection of drugs) and irreversible electroporation. E2 ablates clinically relevant volumes of tissue in a shorter period of time than electrolysis and electroporation, without the need to inject drugs as in reversible electroporation or use paralyzing anesthesia as in irreversible electroporation
Recuperação por conteudo em grandes coleções de imagens heterogeneas
Orientador: Alexandre Xavier FalcãoTese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação CientificaResumo: A recuperação de imagens por conteúdo (CBIR) é uma área que vem recebendo crescente atenção por parte da comunidade científica por causa do crescimento exponencial do número de imagens que vêm sendo disponibilizadas, principalmente na WWW. À medida que cresce o volume de imagens armazenadas, Cresce também o interesse por sistemas capazes de recuperar eficientemente essas imagens a partir do seu conteúdo visual. Nosso trabalho concentrou-se em técnicas que pudessem ser aplicadas em grandes coleções de imagens heterogêneas. Nesse tipo de coleção, não se pode assumir nenhum tipo de conhecimento sobre o conteúdo semântico e ou visual das imagens, e o custo de utilizar técnicas semi-automáticas (com intervenção humana) é alto em virtude do volume e da heterogeneidade das imagens que precisam ser analisadas. Nós nos concentramos na informação de cor presente nas imagens, e enfocamos os três tópicos que consideramos mais importantes para se realizar a recuperação de imagens baseada em cor: (1) como analisar e extrair informação de cor das imagens de forma automática e eficiente; (2) como representar essa informação de forma compacta e efetiva; e (3) como comparar eficientemente as características visuais que descrevem duas imagens. As principais contribuições do nosso trabalho foram dois algoritmos para a análise automática do conteúdo visual das imagens (CBC e BIC), duas funções de distância para a comparação das informações extraídas das imagens (MiCRoM e dLog) e urna representação alternativa para abordagens que decompõem e representam imagens a partir de células de tamanho fixo (CCIf)Abstract: Content-based image retrieval (CBIR) is an area that has received increasing attention from the scientific community due to the exponential growing of available images, mainly at the WWW.This has spurred great interest for systems that are able to efficiently retrieve images according to their visual content. Our work has focused in techniques suitable for broad image domains. ln a broad image domain, it is not possible to assume or use any a p1'ior'i knowledge about the visual content and/or semantic content of the images. Moreover, the cost of using semialitomatic image analysis techniques is prohibitive because of the heterogeneity and the amount of images that must be analyzed. We have directed our work to color-based image retrieval, and have focused on the three main issues that should be addressed in order to achieve color-based image retrieval: (1) how to analyze and describe images in an automatic and efficient way; (2) how to represent the image content in a compact and effective way; and (3) how to efficiently compare the visual features extracted from the images. The main contributions of our work are two algorithms to automatically analyze the visual content of the images (CBC and BIC), two distance functions to compare the visual features extracted from the images (MiCRoM and dLog), and an alteruative representation for CBIR approaches that decompose and represent images according to a grid of equalsized cells (CCH)DoutoradoDoutor em Ciência da Computaçã
Prostate cancer treatment with Irreversible Electroporation (IRE): Safety, efficacy and clinical experience in 471 treatments.
BackgroundIrreversible Electroporation (IRE) is a novel image-guided tissue ablation technology that induces cell death via very short but strong pulsed electric fields. IRE has been shown to have preserving properties towards vessels and nerves and the extracellular matrix. This makes IRE an ideal candidate to treat prostate cancer (PCa) where other treatment modalities frequently unselectively destroy surrounding structures inducing severe side effects like incontinence or impotence. We report the retrospective assessment of 471 IRE treatments in 429 patients of all grades and stages of PCa with 6-year maximum follow-up time.Material and findingsThe patient cohort consisted of low (25), intermediate (88) and high-risk cancers (312). All had multi-parametric magnetic resonance imaging, and 199 men had additional 3D-mapping biopsy for diagnostic work-up prior to IRE. Patients were treated either focally (123), sub-whole-gland (154), whole-gland (134) or for recurrent disease (63) after previous radical prostatectomy, radiation therapy, etc. Adverse effects were mild (19.7%), moderate (3.7%) and severe (1.4%), never life-threatening. Urinary continence was preserved in all cases. IRE-induced erectile dysfunction persisted in 3% of the evaluated cases 12 months post treatment. Mean transient IIEF-5-Score reduction was 33% within 12-month post IRE follow-up and 15% after 12 months. Recurrences within the follow-up period occurred in 10% of the treated men, 23 in or adjacent to the treatment field and 18 outside the treatment field (residuals). Including residuals for worst case analysis, Kaplan Maier estimation on recurrence rate at 5 years resulted in 5.6% (CI95: 1.8-16.93) for Gleason 6, 14.6% (CI95: 8.8-23.7) for Gleason 7 and 39.5% (CI95: 23.5-61.4) for Gleason 8-10.ConclusionThe results indicate comparable efficacy of IRE to standard radical prostatectomy in terms of 5-year recurrence rates and better preservation of urogenital function, proving the safety and suitability of IRE for PCa treatment. The data also shows that IRE, besides focal therapy of early PCa, can also be used for whole-gland ablations, in patients with recurrent PCa, and as a problem-solver for local tumor control in T4-cancers not amenable to surgery and radiation therapy anymore
Giving in Minnesota 2010 Edition Summary
This summary reports highlights from the Minnesota Council on Foundations' Giving in Minnesota, 2010 Edition research report, the most comprehensive analysis of charitable giving in the state. The 2010 edition features Minnesota giving in 2008, the most recent year for which comprehensive data are available. This report includes information about overall giving by foundations, corporations and individuals in Minnesota, along with detailed grantmaking trends by the Giving in Minnesota sample, which is comprised of 100 of the state's largest grantmakers based on grants paid
On Maximum Cycle Packings in Polyhedral Graphs
This paper addresses upper and lower bounds for the cardinality of a maximum vertex-/edge-disjoint cycle packing in a polyhedral graph G. Bounds on the cardinality of such packings are provided, that depend on the size, the order or the number of faces of G, respectively. Polyhedral graphs are constructed, that attain these bounds
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