Non-coding RNAs are highly abundant regulators of gene expression in all kingdoms of life that often play important roles in vital cellular functions. In bacteria, small regulatory RNAs (sRNAs) usually act post-transcriptionally by regulating mRNAs through base pairing within ribosome binding sites (RBS), thereby inhibiting translation initiation. tisB encodes a toxin, TisB, whose synthesis is controlled by the sRNA IstR-1. Intriguingly, IstR-1 base pairs far upstream of the RBS but nevertheless inhibits translation initiation. The tisB mRNA is unusual in that ribosomes cannot access the RBS directly, but instead need an unstructured upstream region. This is precisely where IstR-1 exerts its inhibitory effect. We propose this region to serve as a ribosome loading site (standby site) which permits ribosomes to overcome the obstacle of inhibitory RBS-containing structures. Sequence-independent ribosome binding to the standby site allows for efficient relocation to the RBS structure when it is transiently open. Thus, standby sites are translation enhancer elements. I also characterized TisB-mediated toxicity. The hydrophobic protein TisB is targeted to the inner membrane and causes damage. This decreases the intracellular ATP concentration and entails decreased  replication, transcription and translation rates. It is likely that this toxin is involved in multidrug tolerance under certain conditions. We identified the sRNA MicF as a negative regulator of lrp expression. Lrp is a global transcription factor that controls genes involved in amino acid metabolism and transport of small molecules. Interestingly, Lrp also downregulates MicF. Thus, this study established that the mutual downregulation of MicF/Lrp creates a positive feedback loop which gives a switch-like behavior important for fast adaptations.

Orientador: Jose Antenor Pomilio / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-07T10:48:39Z (GMT). No. of bitstreams: 1 Martins_GeomarMachado_D.pdf: 4129472 bytes, checksum: 7290e97be14c6528a200531ef75ad6b8 (MD5) Previous issue date: 2006 / Resumo: A conexão de fontes de geração distribuída com' a rede geralmente necessita de um conversor eletrônico para processar a energia gerada localmente e injetá-la na rede. Este trabalho apresenta um sistema de geração distribuída para baixas potências, composto por uma fonte primária em CC, como uma Célula a Combustível. Um conversor elevador boost conecta a fonte primária a um inversor trifásico comutado em baixa freqüência que injeta a energia na rede e garante a sua qualidade. Um circuito auxiliar é agregado à topologia do inversor com a finalidade de reduzir a distorção de sua tensão de saída, dessa forma melhorando a forma de onda da corrente. A estratégia de controle empregada permite um desempenho seguro mesmo com as flutuações na energia gerada. As principais vantagens desta proposta são a minimização das perdas de chaveamento (ou seja, alto rendimento) e a eliminação de IEM (o que evita o uso de filtros de altas freqüências comuns nos conversores chaveados em alta freqüência). Os procedimentos de projeto são estabelecidos com vistas à redução do volume dos elementos empregados no circuito, buscando uma densidade de potência mais alta. Um protótipo de 1300 V A é implementado e testado. Os resultados obtidos confirmam a análise teórica / Abstract: The connection of distributed power sources with the utility grid generally needs an electronic power converter for processing the locally generated power and injecting current into the system. This work presents a system intended to low-power distributed generation composed by a DC primary source, as a fuel cell. A boost converter connects the supply to an inverter, composed by a three-phase one using low-frequency commutation, which injects the power into the grid and guarantees the AC power quality. An auxiliary circuit is added to the inverter topology in order to reduce the output voltage distortion, thus improving the current waveform. The employed control strategy allows a secure performance even if there are fluctuations in the generated power. The main advantages of this approach are the minimization of the switching losses (i.e. high efficiency) and the elimination of the EMI (which avoids high-frequency filters necessary in high-frequency commutation inverters). Design procedures are established permiting to reduce the volume of the elements, seeking a high power density. A 1300 V A converter prototype is implemented and tested. The obtained results confirm the theoretical analysis / Doutorado / Energia Eletrica / Doutor em Engenharia Elétrica

The work deals with communication options, the power line and particularly the use of this technology in home automation to control heating and reduction in standby mode for selected domestic appliances. The issue is outlined in detail first and then examined in detail. The publication outlines a possible variant of such a device that can detect movement in the house and on the basis of such information to adjust the energy profile. The device is from its base designed to minimize the consumption of heat and electricity.

My thesis is engaged in business development of company Iveco Czech Republic, s.r.o. I would like to review current situation and then work up plan how to improve this situation.

This thesis deals with the systems reliability. At First, there is discussed the concept of reliability itself and its indicators, which can specifically express reliability. The second chapter describes the different kinds of reliability models for simple and complex systems. It further describes the basic methods for construction of reliability models. The fourth chapter is devoted to a very important Markov models. Markov models are very powerful and complex model for calculating the reliability of advanced systems. Their suitability is explained here for recovered systems, which may contain absorption states. The next chapter describes the standby redundancy. Discusses the advantages and disadvantages of static, dynamic and hybrid standby. There is described the influence of different load levels on the service life. The sixth chapter is devoted to the implementation, description of the application and description of the input file in XML format. There are discussed the results obtaining in experimental calculations.

This master's thesis report deals with the theoretical analysis of FHRP. First Hop Redundancy Protocols are network protocols which are designed to protect the default gateway and also to ensure high availability in the network by using redundancy. The reader becomes familiar with protocols VRRP, HSRP and GLBP and also learn the way how to configure them to on real Cisco devices. It also describes how implement VRRP int the simulated enviroment of OMNeT++. The result of the implementation is verified in the test topologies.

The current shift towards renewable energy resources creates volatility in the electricity production that must be compensated by nevi sources of balancing energy. To ensure a normal operation of the power system, the transmission system operators procure power reserves able to provide regulation energy through market processes. Virtual power plants are now likely to participate on the balancing markets. In this study, the technical and economic feasibility of having virtual power plants participate in the Swiss balancing market is assessed. The study begins with the evaluation and compa.rison of four European balancing market designs and continues with the clarification of the concept of virtual power plant. The focus is then set on the Swiss ancillary services market, recently open to virtual pmver plants. After a detailed market description, an economic model simulating the participation of a virtual power plant made of industrial resources on the secondary and tertiary control markets has been developed. This model \Vas evaluated on an actual market design: the Sv.riss ancillary servicel:l market. 5 cases were simulated, allowing to estimate the opportunity fom both the capacity and the energy market productl:l. The simulations indicated that an example company (based on an actual situation) could hope a decrease in its energy cost between :3 and 4% by participating in a control pool over a year. Other simulations demonstrated the greater profit expected from secondary reserves compared to tertiary rel:lerves, and the need to develop an automatized activation system. The encouraging economic study is followed by a technical overview of the envisioned system. A generic technical characterization of virtual power plant is presented, on v.rhich the Swiss use-case is later applied. The breakdown into functional requirements allowed to highlight specific issues. The design of the control strategy, particularly to deliver secondary control, as well as the hardware communication interface to use are tvw aspects that ,vill require further analysis. Additionally, on an economic level, the investment cost for remote communication modules are acceptable with respect to the economic potentials estimated in the first part, for medium­sized industrial energy resources. In conclusion, the study established the profitability of an aggregation project on the Swisl:l market but also demonstrated the need to pursue research for the project to be fully feasible on a technical level.

在二十世紀末的今天，國際間的技術輸出、工程開發、勞務僱傭以及精密技術的移轉等均有別於傳統有形物品的國際貿易，其金額與規模的鉅大，交易的頻繁，均呈現空前繁盛的情況，尤其國際間的營建工程也已成為國際貿易的一大項目，實乃始料所未及。由於工程龐大，涉及貨物或勞務的供應以及工作的履行，且需某種程度的技術與經驗,為確保工程依特定的規格或品質如期完成,業主乃要求承包商提供可靠的擔保，此乃國際上公認的正常保障措施。擔保的形式很多，擔保信用狀和「獨立性（單據化）的銀行保證函」乃最普遍、最常見，也最容易被各方所接受。雖然保證或保險公司也願簽發此種獨立性質的擔保函，而銀行也會有簽發傳統的從屬性保證函的情形，但銀行簽發的獨立性保證函與擔保信用狀仍為目前國際貿易上最盛行、最具代表性的保證方式，且其用途已不限於確保營建工程的履行，目前已被廣泛使用在各種層面的擔保上。但我國及其他大部分國家均未對此種與傳統民法炯異的銀行獨立性保證函加以立法，而許多人對此種獨立於基礎契約的保證也一知半解，因此易滋困擾。本研究的目的即欲提昇國人對獨立性銀行保證函的了解和認知，以利其發展。此外，針對受益人對獨立性銀行保證函的濫用及不公平索償的風險，本文也欲藉著探討擔保函中的條款及其所可能帶來的風險，而使當事人能於擬訂擔保函內容時，即將開發擔保函的風險減到最低。而為了與傳統民法所提的保證加以區別，本論文特將「獨立性的銀行保證函」稱為「銀行擔保函」(letterof bank guarantee)或簡稱為「擔保函」(letter of guarantee),以免因觀念相混淆而產生誤解。此外，由於擔保信用狀與銀行擔保函誠為一體兩面的擔保文件，故本文所稱的「銀行擔保函」或「擔保函」，實乃包括「擔保信用狀」。故除非必要，才會特別提及「擔保信用狀」一語，否則，本文所談有關銀行擔保函的性質、內容等，將適用擔保信用狀。

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