Vegetation of post-mining sites determines soil microbial community structure and soil processes Mgr. Michaela Urbanová Abstract The aim of this thesis, which consists of four published articles, was to investigate the effect of vegetation on soil microbial communities and processes in de novo developing soil substrate on the brown-coal spoil heaps in the surrounding of city Sokolov. Spoil material - soil clayey substrate, which had been gradually mined from the opencast brown coal mine, stratified onto spoil heaps and reclaimed by assisted afforestation with selected tree species or left for spontaneous plant succession, changes its biotic and abiotic characteristic in the course of time and particularly under the influence of plants. Changes of spoil substrate characteristics are related to the growth of plant roots and particularly also to the production of plant biomass, which is decomposed gradually and takes part of soil, where participates to soil organic matter. The process of plant dead materials decomposition and transformation is the function of the activity of soil organisms and among them notably soil microorganisms. Moreover, the presence of many of them is closely related to the presence of vegetation, whose symbionts or pathogens are. The exact mechanisms of the plant-microbes interactions...

Estudar a estrutura de remuneração de um país é importante por várias razões. Talvez uma das principais seja porque a remuneração pode afetar a atratividade da carreira e a habilidade dos profissionais que exercem a função de professor. O presente trabalho buscou comparar a diferença do salário-hora entre professores e não professores graduados em carreiras tipicamente relacionadas à profissão docente: Ciências da Educação, Formação de Professores, Língua Materna, Matemática, Biologia e Química. O objetivo era entender como profissionais recém-graduados escolheram diferentes ocupações (docente versus não docente) levando ao aparecimento de um diferencial salarial importante já nos primeiros anos de vida profissional. Desta análise, sob a hipótese de ignorabilidade e a hipótese de preferências semelhantes antes do ingresso no ensino superior corretamente especificadas, pode-se concluir que aqueles que exercem a profissão de professor, tanto na média, quanto no quantil 10 e na mediana, possuem um diferencial de salário hora positivo com relação aos que não são docentes. Já no quantil 90, não há diferença de salário entre os grupos. Os resultados mostram também que a diferença é explicada majoritariamente pelo retorno às características que determinam o salário e menos por diferenças nos níveis de tais características. Existem duas implicações desses resultados. Primeiro, considerando-se salário como proxy para habilidade, pode-se inferir que os professores já são os mais habilidosos da amostra analisada. Sendo assim, aumentar o salário dos docentes não atrairia profissionais mais habilidosos para a profissão, dentro das carreiras estudadas, pois já são os profissionais mais habilidosos que são docentes. Uma alternativa seria capacitar esses profissionais de forma a aumentar a habilidade destes. Segundo, outra forma de aumentar a habilidade dos professores seria compreender como esse diferencial salarial afeta a decisão de ingresso na carreira docente, e buscar atrair profissionais mais habilidosos para o magistério antes da escolha da carreira a ser cursada no ensino superior. Isso poderia possibilitar que indivíduos com maior habilidade se interessassem pelo magistério. Em ambos os casos, para que seja efetivo para a geração de capital humano, um aumento salarial do cargo de professor deve estar atrelado à criação de condições para o aumento da habilidade dos profissionais que ocupam tal posição. / Studying the compensation structure of a country is important for several reasons. Perhaps the most important of them is because the compensation can affect the attractiveness of the teaching profession and the professional skill of performing the job. This study aimed to compare the difference in hourly wage between teachers and teachers in undergraduate careers typically related to the teaching profession: Education Sciences, Teacher Training, First Language, Mathematics, Biology and Chemistry. The objective was to understand how newly graduated professionals chose different occupations (teaching versus non-teaching) leading to the appearance of a major wage differential in the first years of working life. This analysis, under the hypothesis and the hypothesis ignorabilidade similar preferences before entering higher education properly specified, one can conclude that those who exercise the teaching profession, both on average and in 10 quantile and median of a positive differential hourly wage with respect to non-teachers. You quantile 90, there is no difference in pay between groups. The results also show that the difference is largely explained by the return of the characteristics that determine wages and less by differences in the levels of these characteristics. There are two implications of these results. First, considering salary as textit proxy for skill, it can be inferred that teachers are already the most skilled of the sample analyzed. Thus, increasing teacher salaries would attract more skilled professionals for the profession within the careers studied because they are already the most skilled professionals who are teachers. One such alternative would enable professionals to increase the ability of these. Second, another way to increase the ability of teachers would understand how this wage gap affects the decision of entering the teaching career, and seek to attract more skilled professionals for teaching before the choice of higher education. This could enable individuals with greater ability to be interested by the magisterium. In both cases, to be effective for the generation of human capital, a raise from his professorship should be linked to the creation of conditions for increasing the ability of professionals who hold such a position.

Considerando a importância da ciclagem de nutrientes como indicador na manutenção da produtividade do ecossistema, o presente estudo teve como objetivo avaliar a dinâmica sazonal de produção e taxa de decomposição de serapilheira em um fragmento de Cerrado sensu stricto. Para avaliação de aporte de serapilheira foram utilizados 50 coletores circulares com 112,8 cm de diâmetro, distribuídos sistematicamente. As coletas de serapilheira foram realizadas mensalmente de junho de 2016 a maio 2017 e o material coletado foi acondicionado em sacos plásticos, posteriormente levados para o laboratório onde foi realizada a separação nas frações folhas, galhos e material reprodutivo. Posteriormente, o material foi embalado em sacos de papel e levado à estufa à temperatura de 70 oC, para a determinação do peso seco. A decomposição da serapilheira foi avaliada utilizando-se o método de litter bags, com distribuição aleatória de 288 litter bags que continham 20 gramas de folhas e 24 litter bags que continham 20 gramas de galhos. A produção anual de serapilheira foi quantificada em 6.042,50 kg.ha-1.a-1, em que a fração foliar foi predominante apresentando uma produção de 4.644,40 kg.ha-1.a-1, seguida da fração galhos (1.084,10 kg.ha-1.a-1) e material reprodutivo (329,90 kg.ha-1.a-1). A produção de serapilheira obteve maior produção no mês de julho com 1.464,00 kg.ha-1 e menor produção no mês de dezembro (138,70 kg.ha-1). Foi observada correlação negativa significativa entre a produção de serapilheira e suas frações com a precipitação pluviométrica e umidade relativa do ar. A decomposição da massa foliar atingiu 49% e a de galhos 50%, durante o período de nove meses, em que a constante de decomposição (k) para massa foliar e para galhos foi de 0,0030 g g-1dia-1. Por esta constante, a estimativa para o desaparecimento de massa total foi estimada em 1.000 dias (29 meses). É possível concluir que a produção de serapilheira apresentou sazonalidade bem marcada, com maior produção durante a época seca e menor na época chuvosa, com forte influência de precipitação e umidade relativa do ar na deposição das folhas. A decomposição se mostrou lenta tanto para folhas como para galhos obtendo assim o valor da constante de decomposição 0,0030 g g-1dia-1 para ambos. / Considering the importance of nutrient cycling as an indicator in the maintenance of the productivity of the ecosystem, the present study aimed to assess the seasonal dynamics of production and decomposition rate of litter in a fragment of Cerrado sensu stricto. For evaluation of supply of burlap were used 50 circular collectors with 112.8 cm diameter, distributed systematically. Litter collections were performed monthly June 2016-may 2017 and the collected material was packed in plastic bags, then taken to the laboratory where the separation was carried out in fractions leaves, twigs and reproductive material. After that, the material was packed in paper bags and washed the greenhouse at the 70 C, for the determination of the dry weight. The decomposition of leaf litter was evaluated using the method of litter bags, with random distribution of 288 litter bags containing 20 grams of leaves and 24 litter bags containing 20 grams of branches. The annual production of litterfall was quantified in 6.042,50 kg. ha-1. yr- 1, in which the leaf was prevalent fraction presented a production of 4.644,40 kg. ha-1. yr-1, then the fractions branches (1.084,10 kg. ha-1. yr-1) and reproductive material (329,90 kg. ha-1. yr-1). The litterfall obtained higher production in July with 1.464,00 kg. ha-1 and lower production in the month of December (138,70 kg. ha-1). A significant negative correlation was observed between litterfall and its fractions with the precipitation and relative humidity. The decomposition of foliar mass reached 49% and 50% of twigs during the nine-month period, in which the decomposition constant (k) for leaf mass and for branches was 0.0030 g g-1-1day.For this constant, the estimate for the disappearance of total mass has been estimated to be 1.000 days (29 months). It can be concluded that the litterfall presented seasonality well marked, with higher output during the dry season and lower in the rainy season with strong influence of precipitation and relative humidity in the deposition of the leaves. The breakdown proved slow for both leaves as for branches to get the value of the constant of decomposition 0.0030 g g-1-1 day for both.

This thesis aims to examine energy demand within UK industry and assess the improvement potential available through efficiency measures. The techniques employed throughout the work have been mainly engineering based, drawing on thermodynamics. Alongside this approach, an assessment of drivers and barriers to the technical potential was undertaken. Data availability was a key challenge in the current work. The variety in energy uses meant the use of publically available datasets was limited. A database was constructed utilising site level emissions data, and employed a subsector disaggregation that facilitated energy analysis. The database was used for an analysis of waste heat recovery options. Opportunities were identified in low temperature recovery, heat-ta-power technology, and the transport of heat. Each of these options would require further research and support to be fully realised. It was found that splitting the industrial sector into an energy-intensive and non-energy- intensive subsector, where the grouping was based on the drivers to energy efficiency, allowed generalisations to be made regarding future improvement potential. Based on analysis of past trends, it was found that the energy-intensive subsector has limited potential for further efficiency gains through currently used processes. To make significant improvements radical changes in current processes will be required. A study of the energy-intensive Cement subsector concurred with these findings. Future efficiency improvements in this subsector are likely limited without a shift to alternative cement production. The non-energy-intensive subsector was thought to have relatively greater improvement potential through existing processes. The analysis of these processes is limited by lack of data however. An analysis of the non-energy-intensive Food and drink subsector therefore focussed on improvements in supplying low temperature heat, rather than the efficiency of specific processes. Opportunities through improving steam systems, increasing combined heat-and-power use, and the adoption of heat pumps were found to offer similar improvement potentials.

Yan, Kan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 64-[66]). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.

Since their conception by Collins in 1975, Cylindrical Algebraic Decompositions (CADs) have been used to analyse the real algebraic geometry of systems of polynomials. Applications for CAD technology range from quantifier elimination to robot motion planning. Although of great use in practice, the CAD algorithm was shown to have doubly exponential complexity with respect to the number of variables for the problem, which limits its use for large examples. Due to the high complexity of CAD, much work has been done to improve its performance. In this thesis new advances will be discussed that improve the practical efficiency of CAD for a variety of problems, with a new complexity result for one set of algorithms. A new invariance condition, truth table invariance (TTICAD), and two algorithms to construct TTICADs are given and shown to be highly efficient. The idea of restricting the output of CADs, allowing for greater efficiency, is formalised as sub-decompositions and two particular ideas are investigated in depth. Efficient selection of various formulation choices for a CAD problem are discussed, with a collection of heuristics investigated and machine learning applied to assist in choosing an optimal heuristic. The mathematical expression of a problem is shown to be of great importance, with preconditioning and reformulation investigated. Finally, these advances are collected together in a general framework for applying CAD in an efficient manner to a given problem. It is shown that their combination is not cumulative and care must be taken. To this end, a prototype software CADassistant is described to help users take advantage of the advances without knowledge of the underlying theory. The effects of the various advances are demonstrated through a guiding example originally considered by Solotareff, which describes the approximation of a cubic polynomial by a linear function. Naïvely applying CAD to the problem takes 916.1 seconds of construction (from which a solution can easily be derived), which is reduced to 20.1 seconds by combining various advances from this thesis.

This project explores how to use band-pass filtering with a variety of filters to filter both two and three dimensional surface data. The software developed collects and makes available these filtering methods to support a larger project. It is used to automate the filtering procedure. This paper goes through the work-flow of the program, explaining how each filter was implemented. Then it demonstrates how the filters work by applying them to surface data used to test correlation between friction and roughness [Berglund and Rosen, 2009]. It also provides some explanations of the mathematical development of the filtering procedures as obtained from literature.

This thesis considers a novel problem of obtaining global channel state information (CSI) at every node in an ad-hoc wireless network. A class of protocols for dissemination and estimation are developed which attempt to minimize the staleness of the estimates throughout the network. This thesis also provides an optimal protocol for CSI dissemination in networks with complete graph topology and a near optimal protocol in networks having incomplete graph topology. In networks with complete graph topology, the protocol for CSI dissemination is shown to have a resemblance to finding Eulerian tours in complete graphs. For networks having incomplete graph topology, a lower bound on maximum staleness is given and a near optimal algorithm based on finding minimum connected dominating sets and proper scheduling is described in this thesis.

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