Absolute diffusion measurements of active enzyme solutions by NMR

The diffusion of enzymes is of fundamental importance for many biochemical processes. Enhanced or directed enzyme diffusion can alter the accessibility of substrates and the organization of enzymes within cells. Several studies based on fluorescence correlation spectroscopy (FCS) report enhanced diffusion of enzymes upon interaction with their substrate or inhibitor. In this context, major importance is given to the enzyme fructose-bisphosphate aldolase, for which enhanced diffusion has been reported even though the catalysed reaction is endothermic. Additionally, enhanced diffusion of tracer particles surrounding the active aldolase enzymes has been reported. These studies suggest that active enzymes can act as chemical motors that self-propel and give rise to enhanced diffusion. However, fluorescence studies of enzymes can, despite several advantages, suffer from artefacts. Here we show that the absolute diffusion coefficients of active enzyme solutions can be determined with Pulsed Field Gradient Nuclear Magnetic Resonance (PFG-NMR). The advantage of PFG-NMR is that the motion of the molecule of interest is directly observed in its native state without the need for any labelling. Further, PFG-NMR is model-free and thus yields absolute diffusion constants. Our PFG-NMR experiments of solutions containing active fructose bisphosphate aldolase from rabbit muscle do not show any diffusion enhancement for the active enzymes nor the surrounding molecules. Additionally, we do not observe any diffusion enhancement of aldolase in the presence of its inhibitor pyrophosphate

Existence of positive solutions to stochastic thin-film equations

We construct martingale solutions to stochastic thin-film equations by introducing a (spatial) semidiscretization and establishing convergence. The discrete scheme allows for variants of the energy and entropy estimates in the continuous setting as long as the discrete energy does not exceed certain threshold values depending on the spatial grid size $h$. Using a stopping time argument to prolongate high-energy paths constant in time, arbitrary moments of coupled energy/entropy functionals can be controlled. Having established Hölder regularity of approximate solutions, the convergence proof is then based on compactness arguments---in particular on Jakubowski's generalization of Skorokhod's theorem---weak convergence methods, and recent tools on martingale convergence

Our Common Cropland: Quantifying Global Agricultural Land Use from a Consumption Perspective

Understanding teleconnections of regional consumption patterns and global land use supports policy making towards achieving sustainable land use. We present an innovative globally consistent hybrid land-flow accounting method to track biomass flows and embodied land along global supply chains. It uses the large FAOSTAT database, which is, for non-food commodities, complemented with a multi-regional input-output model. We employ the hybrid model globally between 1995 and 2010 and present results for regional markets. Results highlight the growing integration in international markets. In 2010, 31% of cropland cultivation was for export markets compared to 16% in 1995. The higher land demand of livestock-based diets, which account for one third of global cropland use, and differences in land use intensities cause large regional variations in extents and composition of land footprints. The utilization of cropland changed towards a growing importance of the non-food sector accounting for 12% in 2010. Comparing land quality weighted cropland footprints across regions further reveals large differences in the appropriation of available global cropland productivity. Because of large uncertainties and quality differences in the actual use of grassland for feeding ruminants, we propose land quality weighted grassland footprints to discuss the additional land use for ruminant livestock products

O Design de experiências em interfaces web: um estudo de levantamento para pesquisa de usuários baseado em uma rede social

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão, Programa de Pós-Graduação em Design e Expressão Gráfica, Florianópolis, 2010Esse estudo trata da experiência dos usuários em interfaces web, e tem como objetivo identificar quais são os componentes mais influentes da experiência sobre a interação. A partir de uma categorização da experiência em aspectos estéticos, emocionais e hedônicos, desenvolveu-se um instrumento de pesquisa, aplicado a um grupo de usuários. Com os resultados obtidos é proposta uma discussão acerca da natureza do Design. Enquanto o design de experiências mostra-se como disciplina em consolidação, o Design em sentido amplo adquire implicações epistemológicas que o orientam ora para a arte, ora para engenharia. Os resultados da pesquisa mostram que o componente hedônico da eficiência ainda é tido como mais significativo pelos usuários

Práticas de liderança na escola pública: um estudo comparativo

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia e Gestão do Conhecimento, Florianópolis, 2017.As escolas e o trabalho pedagógico são de relevância social inestimável e a liderança é um dos fatores que contribuem para a melhoria da qualidade de um centro de ensino. Pelas peculiaridades das escolares públicas brasileiras, a abordagem da liderança como prática se mostra um caminho viável, promissor e alinhado ao enfrentamento dessa realidade. Com esta tese busquei compreender o processo de liderança em duas escolas públicas de ensino fundamental, sob a perspectiva da liderança como prática, no município de Florianópolis (SC). Para tanto, utilizou-se o método da pesquisa qualitativa, mediante anotações de campo e entrevistas dos colaboradores que compunham a equipe de gestão de cada escola: nove pessoas em uma escola e cinco pessoas na outra. Sobre as transcrições e anotações de campo foi aplicada a análise temática, a partir da qual foram identificadas 12 práticas de liderança: ?conjuntação?, criação e fortalecimento de vínculos, facilitação e suporte, ?formativação?, gestão de conflitos, gestão de urgências, orientação, planejamento, gestão partilhada, acompanhamento, educação por projetos e readaptação. As práticas que mais contribuem para a dinâmica do processo de liderança e demonstram mais consistência são: criação e fortalecimento de vínculos; readaptação; ?conjuntação?; gestão compartilhada; e orientação. As descrições das práticas de liderança foram feitas com base em seus principais elementos: pessoas, ação, modo, motivos e contexto. Percebi livre inter-relação entre esses elementos e a massiva influência do contexto não institucional sobre essas práticas. Concluí que o trabalho de liderança é em grande parte emergente e baseado na experiência, pela influência e imprevisibilidade que o contexto exerce sobre a prática. O diálogo, a conversa, o acompanhamento, a união, a aproximação, o vínculo e o senso de missão compõem a maneira pela qual a liderança escolar é efetivada.Abstract : The schools and their pedagogical work has inestimable social relevance. Leadership is one of the factors that contribute to improving the quality of an educational institution. Due to the peculiarities of Brazilian public schools, the leadership as practice approach shows a viable, promising and aligned path to face this reality. In this research I sought to understand the leadership process in two public elementary schools, from the perspective of leadership as practice, in the city of Florianópolis (SC/Brazil). For this purpose, the method of qualitative research was used, using field notes and interviews with the employees that comprised the management team of each school: nine people in one school and five people in the other. The thematic analysis was applied on transcripts and field annotations, from which 12 leadership practices were identified: joint action efforts, creation and strengthening of bonds, facilitation and support, formative actions, conflict management, emergency management, guidance, planning, shared management, monitoring, education through projects and readaptation. The practices that most contribute to the dynamics of the leadership process and demonstrate more consistency are: creating and strengthening bonds; readaptation; joint action; shared management; and guidance. Descriptions of leadership practices were made based on their main elements: people, action, mode, motives, and context. I was able to perceive the free interrelationship between these elements and the massive influence of the non-institutional context on these practices. I conclude that leadership work is largely emergent and based on experience, due to the influence and unpredictability that the context exerts on practice. The dialogue, the conversation, monitoring, the union, the approach, the bond and the sense of mission make up the manner in which the school leadership is effective

Estrutura organizacional e implementação da estratégia: o caso da Softplan

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Sócio Econômico, Programa de Pós-Graduação em Administração, Florianopolis, 2011Esta dissertação versa sobre estrutura organizacional e implementação da estratégia. Percebe-se que ainda é difícil e complexo implementar a estratégia e encontrar as estruturas organizacionais certas para determinada estratégia é, portanto, fundamental para o sucesso prático. Diante disso, esta pesquisa tem como objetivo geral analisar os aspectos da estrutura organizacional que favorecem a implementação da estratégia. Metodologicamente, caracteriza-se por ser predominantemente qualitativa e utiliza o estudo de caso na empresa Softplan como unidade de análise, pautado em 20 categorias de análise e obtenção de dados por entrevistas com gerentes e coordenadores (pessoas que concentram a operação da implementação da estratégia) e aplicação de questionários para obter a percepção dos colaboradores sobre o processo de implementação. Obteve-se, então, 23 aspectos da estrutura organizacional favoráveis à implementação da estratégia, quais sejam: gerentes que convertam necessidades externas e internas em ações; indicadores definidos junto à equipe; normas e planos formais; informação adequada disponível; uso de painel e sistemas para gerenciamento de indicadores e ações; acompanhamento regular para avaliação da implementação; obtenção de informações junto ao cliente para entendimento do ambiente; divulgação formal da estratégia, com integração de meios e linguagem; metas financeiras bem definidas; incentivos atrelados à estratégia; uso do contato direto para gerenciar questões intangíveis e forças-tarefa para demandas específicas; abertura pra feedbacks entre a equipe; visão integrada entre as unidades de negócio e os projetos; hierarquia bem definida e realização de ajustes administrativos; alocação integrada com alinhamento entre pessoas, processos e recursos, descentralização e priorização e prazos. Em contrapartida, verificou-se também aquilo que não favorece na relação estrutura e implementação da estratégia, resultando em 56 aspectos desfavoráveis

The global cropland footprint of the non-food bioeconomy. ZEF - Discussion Papers on Development Policy No. 253

A rapidly growing share of global agricultural areas is devoted to the production of biomass for non - food purposes. The derived products include, for example, biofuels, textiles, detergents or c osmetics. Given the far - reaching global implications of an expanding non - food bioeconomy, an assessment of the bioeconomy's resource use from a footprint perspective is urgently needed. We determine the global cropland footprint of non - food products with a hybrid land flow accounting model combining data from the Food and Agriculture Organization and the multi - regional input - output model EXIOBASE. The globally interlinked model covers all cropland areas used for the production of crop - and animal - based non - food commodities for the years from 1995 to 2010. We analyse global patterns of raw material producers, processers and consumers of bio-based non-food products, with a particular focus on the European Union. Results illustrate that the EU is a major processer and the number one consumer region of non-food cropland, despite being only the fifth largest producing region. Two thirds of the cropland required to satisfy EU non-food consumption are located in other world regions, giving rise to a significant depe ndency on imported products and to potential impacts on distant ecosystems. With almost 29% in 2010, oilseed production, used to produce, for example, biofuels, detergents and polymers, represents the dominant share in the EU's non-food cropland footprint. There is also a significant contribution of more traditional non-food biomass uses such as fibre crops (for textiles) and animal hides and skins (for leather products). Our study emphasises the importance of comprehensively assessing the implications of the non-food bioeconomy expansion as envisaged in various policy strategies, such as the Bioeconomy Strategy of the European Commission

Demographische Grenzen der Bildungsexpansion: Eine Modellrechnung zur künftigen quantitativen Entwicklung des Berufsbildungs- und Hochschulsystems

"Die Bildungsexpansion der letzten Jahrzehnte hat in den alten Bundesländern praktisch alle Bereiche des Ausbildungssystems erfaßt. Ein weiteres ungebremstes Wachstum der Bildungsnachfrage würde allerdings in absehbarer Zukunft an demographische Grenzen stoßen. Mit Hilfe von Modellrechnungen bis zum Jahr 2020 (Westdeutschland) bzw. 2010 (Ostdeutschland) werden die möglichen Obergrenzen der künftigen Bildungsexpansion und deren Auswirkungen auf das Ausbildungs- und Erwerbssystem der Zukunft abgeschätzt. Als Referenzbasis dienen die Ergebnisse einer Status-quo-Variante. Die Ergebnisse für Westdeutschland zeigen, daß demographisch bedingte Einbrüche im beruflichen Ausbildungssystem zwar langfristig ausgeglichen werden könnten, allerdings mit einem erheblichen Rückgang der Erwerbsbeteiligung junger Altersjahrgänge der Bevölkerung verbunden wären. Die Eintritte in eine berufliche Erstausbildung (Lehre, Berufsfachschule) würden - gemäß der Maximalvariante - bis zum Jahr 2010 auf rund 900 000 ansteigen (1991: knapp 650 000), danach aber aus demographischen Gründen deutlich abnehmen. Die Zahl der Studienanfänger an Hoch- und Fachhochschulen würde - nach einem Rückgang in den 90er und einem allmählichen Anstieg in den folgenden Jahren - mit 260 000 (2015) wieder auf das Niveau zu Anfang der 90er Jahre ansteigen; anschließend ist auch hier, demographisch bedingt, eine Abnahme zu erwarten. Die Entwicklung der Absolventenzahlen folgt diesen Schwankungen mit entsprechender zeitlicher Verzögerung. Seit der Wiedervereinigung hat sich die Ausbildungslandschaft in den neuen Bundesländern gravierend verändert. Sie wurde im wesentlichen nach westlichem Muster neu strukturiert. Im Rahmen eines Anpassungsszenarios wird verdeutlicht, mit welchen Folgen zu rechnen wäre, wenn sich das Bildungs- und Ausbildungsverhalten der nachrückenden Jahrgänge innerhalb von 10 Jahren dem der alten Bundesländer angleichen würde. Die Berechnungen zeigen, daß dann erhebliche Anstrengungen notwendig sein dürften, um die entsprechenden Kapazitäten an Schul-, Ausbildungs- und Studienplätzen bereitzustellen. Die Zahl der Eintritte in die berufliche Erstausbildung würde sich bis zum Jahre 2001 verdoppeln und dann infolge des Geburteneinbruchs Ende der 80er/Beginn der 90er Jahre wieder sinken, läge aber in 2010 mit 124 000 immer noch über dem Ausgangsniveau 1991 (97 000). Der Geburtenrückgang seit 1988/89 wird sich erst nach dem Jahre 2010 gravierend auswirken. Die Entwicklung der Hochschulzugänge verläuft ähnlich: eine Verdoppelung von 31 000 (1991) auf 62 000 im Jahre 2001 und ein anschließender Rückgang auf 53 000 im Jahre 2010. Auf die Absolventenzahlen wirken sich diese Entwicklungen mit entsprechender Verzögerung aus." (Autorenreferat, IAB-Doku)Bildungsnachfrage - Prognose, Bildungsexpansion, demografische Faktoren, Berufsbildungssystem, Hochschulsystem, Bildungsbeteiligung, Westdeutschland, Ostdeutschland, Bundesrepublik Deutschland

High current hollow cathode as a radiometric transfer standard source for the extreme vacuum ultraviolet

A high current hollow cathode source has been developed as a radiometric source standard for the extreme VUV. The source is operated at a constant current of 2 A with an aluminum cathode and helium or argon as buffer gas at pressures of ~1 hPa. The radiance of spectral lines in the wavelength range from 13 to 60 nm has been determined by comparison to the calculable spectral radiant power of the electron storage ring BESSY. An uncertainty of the order of 13% has been achieved for most of the investigated lines. The spectral emission is stable to better than 5% for an operating time of 30 h. An exchange of the cathode restores the original radiance