947 resultados para Mutant Cycle Analysis


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Chagas disease, caused by the parasite Trypanosoma cruzi, is the cause of Chronic chagasic cardiomyopathy (CCC). The prospection of innovative therapeutic agents against CCC is a major task. The recombinant form of 21 (rP21), a secreted T. cruzi protein involved in host cell invasion and on progression of chronic inflammatory processes have been studied as a potential novel therapeutic target. Our present work aimed to verify and investigate the impact of rP21 in the formation of blood vessels in vitro and in vivo. First, tEnd cells were treated with different concentrations of rP21 or bacterial extract and viability and cellular adhesion were evaluated by MTT and angiogenesis inhibition by Matrigel tube formation assay and murine model. To verify the proteolytic activity of rP21 on extracellular matrix (ECM) components, fibrinogen, matrigel and fibronectin was incubated with rP21 or not. In addition, we performed proliferation assays and cell cycle analysis. Furthermore, the accumulation and distribution of F-actin was determined by Phalloidin staining using ImageJ software. Finally, tEnd cells were incubated with rP21 and the mRNA levels were analyzed by real-time PCR. Our results showed that rP21 did not alter cell viability and adhesion, but strongly inhibited vessel formation in vitro and in vivo. Tube formation assay showed that angiogenesis inhibition was dependent of the CXCR4-rP21 binding. In addition to these results, we observed that the rP21 was able to inhibit cell proliferation and promoted a significant reduction in the number of 4n cells (G2/M phase). Moreover, we found that rP21 significantly increased F-actin levels and this protein was able to modulate expression of genes related to angiogenesis and actin cytoskeleton. However, rP21 showed no significant activity on the matrix components. In this sense, we conclude that the rP21-endothelial cells (ECs) interaction via CXCR4 promotes inhibition of vessel formation through a cascade of intracellular events, such as inhibition of ECs proliferation and modulation of the expression of molecules associated with angiogenic processes and actin cytoskeleton.

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Date of Acceptance: 08/05/2014 Acknowledgements The authors are indebted to Julia Römer for assisting with editing several hundred references. Helmut Haberl gratefully acknowledges funding by the Austrian Academy of Sciences (Global Change Programme), the Austrian Ministry of Science and Research (BMWF, proVision programme) as well as by the EU-FP7 project VOLANTE. Carmenza Robledo-Abad received financial support from the Swiss State Secretariat for Economic Affairs.

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Date of Acceptance: 08/05/2014 Acknowledgements The authors are indebted to Julia Römer for assisting with editing several hundred references. Helmut Haberl gratefully acknowledges funding by the Austrian Academy of Sciences (Global Change Programme), the Austrian Ministry of Science and Research (BMWF, proVision programme) as well as by the EU-FP7 project VOLANTE. Carmenza Robledo-Abad received financial support from the Swiss State Secretariat for Economic Affairs.

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Global warming, energy savings, and life cycle analysis issues are factors that have contributed to the rapid expansion of plant-based materials for buildings, which can be qualified as environmental-friendly, sustainable and efficient multifunctional materials. This review presents an overview on the several possibilities developed worldwide about the use of plant aggregate to design bio-based building materials. The use of crushed vegetal aggregates such as hemp (shiv), flax, coconut shells and other plants associated to mineral binder represents the most popular solution adopted in the beginning of this revolution in building materials. Vegetal aggregates are generally highly porous with a low apparent density and a complex architecture marked by a multi-scale porosity. These geometrical characteristics result in a high capacity to absorb sounds and have hygro-thermal transfer ability. This is one of the essential characteristics which differ of vegetal concrete compared to the tradition mineral-based concretes. In addition, the high flexibility of the aggregates leads to a non-fragile elasto-plastic behavior and a high deformability under stress, lack of fracturing and marked ductility with absorbance of the strains ever after having reached the maximum mechanical strength. Due to the sensitivity to moisture, the assessment of the durability of vegetal concrete constitutes one of the next scientific challenging of bio-based building materials.

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In the mid 1990s a previous prohibitions against multi-story buildings higher than two floors with a wooden frame was changed. Today multi-storey buildings are being built in Skellefteå, Sundsvall, Växjö, and Stockholm with others. Despite this only one of five houses being built today has a wooden frame. Since the municipality is a key force to get projects with wooden frames, this papers purpose is to improve tender document for the opportunity to submit bids and building with wooden frames. To help us forward with our work three questions were formulated. 1) What is the basis from a wooden constructions company perspective, of which they determines if they can place a bid or not? 2) What is the difference between tender documents made by a municipality compared to a private buyer? 3) How can tender documents be improved to create an opportunity to place a bid containing an alternative frame system? To answer these questions a literature study was carried out. The literature study is the basis of this paper. To obtain empirical data a document analysis of tender documents was carried out. The result of the study shows that wood frames are hard to adapt to an already finished technical specification, or to a tender document containing an extensive technical specification. To obtain alternative solutions, the buyer should focus on object design, form and function, or a general technical specification. Instead the technical specifications should be drawn up by the supplier, or in collaboration with them. The tender evaluation should be made by the most economically advantageous rather then the lowest price. Then the buyer can evaluate the offers against each other, rather then choosing the lowest price. This also gives the possibility for suppliers to make a bid containing an alternative solution. As a continuation of this paper, we recommend a study on which impact a general technical specification has on the project final cost.  Furthermore a study exploring which possibilities partner procurement can have alternative solutions in the Swedish procurement act. This report deal exclusively with how tender documents should be formulated. Life cycle analysis, carbon dioxide emissions and strength calculations will not be executed. 

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The current energy market requires urgent revision for the introduction of renewable, less-polluting and inexpensive energy sources. Biohydrogen (bioH2) is considered to be one of the most appropriate options for this model shift, being easily produced through the anaerobic fermentation of carbohydrate-containing biomass. Ideally, the feedstock should be low-cost, widely available and convertible into a product of interest. Microalgae are considered to possess the referred properties, being also highly valued for their capability to assimilate CO2 [1]. The microalga Spirogyra sp. is able to accumulate high concentrations of intracellular starch, a preferential carbon source for some bioH2 producing bacteria such as Clostridium butyricum [2]. In the present work, Spirogyra biomass was submitted to acid hydrolysis to degrade polymeric components and increase the biomass fermentability. Initial tests of bioH2 production in 120 mL reactors with C. butyricum yielded a maximum volumetric productivity of 141 mL H2/L.h and a H2 production yield of 3.78 mol H2/mol consumed sugars. Subsequently, a sequential batch reactor (SBR) was used for the continuous H2 production from Spirogyra hydrolysate. After 3 consecutive batches, the fermentation achieved a maximum volumetric productivity of 324 mL H2/L.h, higher than most results obtained in similar production systems [3] and a potential H2 production yield of 10.4 L H2/L hydrolysate per day. The H2 yield achieved in the SBR was 2.59 mol H2/mol, a value that is comparable to those attained with several thermophilic microorganisms [3], [4]. In the present work, a detailed energy consumption of the microalgae value-chain is presented and compared with previous results from the literature. The specific energy requirements were determined and the functional unit considered was gH2 and MJH2. It was possible to identify the process stages responsible for the highest energy consumption during bioH2 production from Spirogyra biomass for further optimisation.

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Inadequate final disposal of municipal solid waste (MSW) is associated with significant greenhouse gas (GHG) emission, environmental, health and safety issues, space consumption, public health and developmental issues in general. The environmental impact of waste is mostly felt in developing countries, inadequate waste management and treatment solution, inadequate policies and outdated practices are some of the factors leading to the significantly high final disposal of waste in dumps in developing countries. Brazil and other developing countries are changing the status quo by adopting polices that will adequately address this problem of inadequate waste management and disposal. Life cycle analysis (LCA) identifies the potential environmental impact of a product though environmental impact assessment, International Organization for Standardization (ISO) created the ISO 14040 and ISO 14044 to serve as principle guidelines for conducting LCA. Various waste treatment solution was applied to identify the waste management solution with the least Global warming potential (GWP) for treating the MSW generated from the city of Rio de Janerio, while reducing significantly final waste disposed in landfill.

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Dissertação para a obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Vias de Comunicação e Transportes

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Dissertação de Mestrado, Ciências Económicas e Empresariais, 18 de Julho de 2016, Universidade dos Açores.

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A preocupação com o meio ambiente, nomeadamente na descarga de águas residuais, consumo de água excessivo e produção de resíduos industriais, está cada vez mais presente no quotidiano. Devido a estas problemáticas, efetuou-se a avaliação de impacte ambiental (AIA) do processo produtivo das rolhas de cortiça naturais, tratamento das águas de cozedura da cortiça (estudo da possível reutilização do efluente tratado) e valorização de subprodutos – resíduo sólido (raspa de cortiça), sendo estes os objetivos propostos para a realização da presente dissertação. Na AIA, efetuada no decorrer das fases da Análise do Ciclo de Vida (ACV), foram selecionadas 8 categorias de impacte – aquecimento global, acidificação, dessecação, toxicidade e ecotoxicidade, eutrofização, consumo de recursos não renováveis e oxidação foto-química. A água de cozedura caracterizou-se por uma elevada carga poluente, apresentando elevada concentração de cor, Carência Química de Oxigénio (CQO), taninos e lenhina e Sólidos Suspensos Totais (SST). O processo de tratamento proposto consistiu num pré-tratamento por ultrafiltração (UF), com membranas de 30.000 e 20.000 MWCO, seguido de adsorção por carvão ativado (comercial e produzido a partir de raspa de cortiça). No tratamento por UF, utilizando uma membrana de 30.000 MWCO, foram obtidas percentagens de remoção para a primeira amostra de água de cozedura de 74,8 % para a cor, 33,1 % para a CQO e para a segunda amostra de 85,2 % para a cor e 41,8 % para a CQO. Posteriormente, apenas para a segunda amostra de água de cozedura e com uma membrana de 20.000 MWCO, as percentagens de remoção obtidas foram superiores, de 93% para a cor, 68,9 % para a CQO, 88,4 % para taninos e lenhina e 43,0 % para azoto total. No tratamento por adsorção com carvão ativado estudou-se o tempo de equilíbrio do carvão ativado comercial e do carvão ativado produzido a partir de aparas de cortiça, seguindo-se o estudo das isotérmicas de adsorção, no qual foram analisados os parâmetros da cor e CQO para cada solução. Os ajustes dos modelos teóricos aos pontos experimentais demonstraram que ambos os modelos (Langmuir e Freundlich) poderiam ser considerados, uma vez que apresentaram ajustes idênticos. Relativamente ao tratamento de adsorção em contínuo do permeado, obtido por UF com membrana de 20.000 MWCO, constatou-se que ambos os carvões ativados (comercial e produzido) não ficaram saturados, tendo em consideração os tempos de saturação estimados pela capacidade máxima de adsorção (determinada para a isotérmica de Langmuir) e as representações gráficas dos valores experimentais obtidos para cada ensaio. No ensaio de adsorção com carvão ativado comercial verificou-se que o efluente tratado poderia ser descarregado no meio hídrico ou reutilizado no processo industrial (considerando os parâmetros analisados), uma vez que até aos 11 minutos de ensaio a concentração da solução à saída foi de 111,50 mg/L O2, para a CQO, e incolor, numa diluição de 1:20. Em relação à adsorção em contínuo com carvão ativado produzido verificou-se no ensaio 4 que o efluente resultante apresentou uma concentração de CQO de 134,5 mg/L O2 e cor não visível, numa diluição de 1:20, ao fim de 1h22 min de ensaio. Assim, concluiu-se que os valores obtidos são inferiores aos valores limite de emissão (VLE) presentes no Decreto-Lei n.º 236/98 de 1 de Agosto. O carvão ativado produzido apresentou elevada área superficial específica, com 870 m2/g, comparativamente ao carvão comercial que foi de 661 m2/g. O processo de extração da suberina a partir de raspa de cortiça isenta de extraíveis, efetuado através da metanólise alcalina, apresentou percentagens de extração superiores aos restantes métodos. No processo efetuado em scale-up, por hidrólise alcalina, obteve-se uma extração de 3,76 % de suberina. A aplicação da suberina no couro demonstrou que esta cera apresenta enormes potencialidades, uma vez que a sua aplicação confere ao couro um aspeto sedoso, com mais brilho e um efeito de “pull-up”.

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Biologia Molecular, 2016.

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Sustainable development has only recently started examining the existing infrastructure, and a key aspect of this is hazard mitigation. To examine buildings under a sustainable perspective requires an understanding of a building's life-cycle environmental costs, including the consideration of associated environmental impacts induced by earthquake damage. Damage repair costs lead to additional material and energy consumption, leading to harmful environmental impacts. Merging results obtained from a seismic evaluation and life-cycle analysis for buildings will give a novel outlook on sustainable design decisions. To evaluate the environmental impacts caused by buildings, long-term impacts accrued throughout a building's lifetime and impacts associated with damage repair need to be quantified. A method and literature review for completing this examination has been developed and is discussed. Using software Athena and HAZUS-MH, this study evaluated the performance of steel and concrete buildings considering their life-cycle assessments and earthquake resistance. It was determined that code design-level greatly effects a building repair and damage estimations. This study presented two case study buildings and found specific results that were obtained using several premade assumptions. Future research recommendations were provided to make this methodology more useful in real-world applications. Examining cost and environmental impacts that a building has through, a cradle-to-grave analysis and seismic damage assessment will help reduce material consumption and construction activities from taking place before and after an earthquake event happens.

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El objetivo de este trabajo es utilizar algunos hechos estilizados de la "Gran recesión", específicamente la drástica caída en el nivel de capitalización bancario, para analizar la relación entre los ciclos financieros y los ciclos reales, así como la efectividad de la política monetaria no convencional y las políticas macroprudenciales. Para esto, en el primer capítulo se desarrolla una microfundamentación de la banca a partir de un modelo de Costly State Verification, que es incluido posteriomente en distintas especificaciones de modelos DSGE. Los resultados muestran que: (i) los ciclos financieros y los ciclos económicos pueden relacionarse a partir del deterioro del capital bancario; (ii) Las políticas macroprudenciales y no convencionales son efectivas para moderar los ciclos económicos, pero son costosas en términos de recursos e inflación.

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Despite numerous therapeutic interventions cancer is still today the second leading cause of death. A growing interest has been addressed to isothiocytanates and more recently, the 6- (methylsulfonyl) hexyl isothiocyanate (6-MITC), the main constituent of the rhizome of Wasabia Japonica, has stimulated the interest of researchers. Aim of the research was to study if 6-MITC is able to modulate the main mechanisms underlying chemopreventive process in leukemic cells lines, verify the selectivity of action and the safety of use in terms of mutagenicity. The study was conducted on different cell types. In particular, Jurkat and HL-60 cells were treated with increasing concentrations of 6-MITC and cell viability, induction of apoptosis, cell cycle analysis, autophagy modulation and stimulation of differentiation were evaluated by flow cytometry. PBL, the non-transformed counterparty of leukemia cells, was used to analyse the selectivity of action by studying the same mechanisms previously indicated. Finally, safety of use and antimutagenicity were studied in TK6 cells adopting an automated protocol in flow cytometry. The achieved results have demonstrated that isothiocyanate modulates many signaling pathways involved in chemopreventive mechanism. In fact, 6-MITC induces apoptosis of both transformed cells, limits tumor growth by slowing down the cell cycle of Jurkat cells and blocks HL-60 cell cycle, increases the autophagic flux and induces cytodifferentiation of promyelocytic HL-60 into macrophage and granulocytic phenotypes. Furthermore, the results obtained with 6-MITC on PBL from healthy donors suggest that the isothiocyante is a good selective cytotoxic agent. Essential feature of a good chemopreventive agent is selectivity toward cancer cells and low toxicity towards non-transformed cells. Finally, the analysis of the micronuclei revealed that 6-MITC is not mutagenic, ensuring safe use, and that instead, it is able to counteract the mutagenic activity of the aneuploidogen Vinblastine, demonstrating another important and interesting chemopreventive activity.

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igments, proteins and enzyme activity related to chlorophyll catabolism were analysed in senescing leaves of wild-type (WT) Lolium temulentum and compared with those of an introgression line carrying a mutant gene from stay-green (SG) Festuca pratensis. During senescence of WT leaves chlorophylls a and b were continuously catabolised to colourless products and no other derivatives were observed, whereas in SG leaves there was an accumulation of dephytylated and oxidised catabolites including chlorophyllide a, phaeophorbide a and 132 OH-chlorophyllide a. Dephytylated products were absent from SG leaf tissue senescing under a light-dark cycle. Retention of pigments in SG was accompanied by significant stabilisation of light harvesting chlorophyll-proteins compared with WT, but soluble proteins such as Rubisco were degraded during senescence at a similar rate in the two genotypes. The activity of phaeophorbide a oxygenase measured in SG tissue at 3d was less than 12% of that in WT tissue at the same time-point during senescence and of the same order as that in young pre-senescent WT leaves, indicating that the metabolic lesion in SG concerns a deficiency at the ring-opening step of the catabolic pathway. In senescent L. temulentum tissue two terminal chlorophyll catabolites were identified with chromatographic characteristics that suggest they may represent hitherto undescribed catabolite structures. These data are discussed in relation to current understanding of the genetic and metabolic control of chlorophyll catabolism in leaf senescence.