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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
561

Caracterização molecular da atividade de interação da proteína RPA-1 com os telômeros de Leishmania spp. / Molecular characterization of the interaction activity of the RPA-1 protein with the telomeres of Leishmania spp.

Santos, Gabriel Arantes Galvão Dias dos 27 April 2018 (has links)
Submitted by Gabriel Arantes Galvão Dias dos Santos (arantes_gabriel@hotmail.com) on 2018-05-14T15:21:05Z No. of bitstreams: 1 Dissertação pós defesa.pdf: 3303163 bytes, checksum: 01b3ceab15b6016a9aaca279d39ebdc5 (MD5) / Approved for entry into archive by Sulamita Selma C Colnago null (sulamita@btu.unesp.br) on 2018-05-14T17:46:54Z (GMT) No. of bitstreams: 1 santos_gagd_me_bot.pdf: 3303163 bytes, checksum: 01b3ceab15b6016a9aaca279d39ebdc5 (MD5) / Made available in DSpace on 2018-05-14T17:46:54Z (GMT). No. of bitstreams: 1 santos_gagd_me_bot.pdf: 3303163 bytes, checksum: 01b3ceab15b6016a9aaca279d39ebdc5 (MD5) Previous issue date: 2018-04-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Entre as espécies do gênero Leishmania estão os protozoários que causam leishmaniose, uma doença tropical negligenciada endêmica em muitos países, incluindo o Brasil. Métodos de controle e tratamento ainda são ineficientes e a resistência a drogas é um desafio. Por isso, pesquisas para entender melhor a biologia molecular desses parasitos são encorajadas. Uma possível estratégia para isso, é o estudo dos telômeros, estrutura fundamental para a homeostase do genoma. Os telômeros são estruturalmente diferentes do resto do cromossomo, e contam com proteínas específicas que realizam sua manutenção. A Replication Protein A subunit 1 (RPA-1) é uma proteína que interage de DNA de simples fita que tem diversas funções relacionadas com o metabolismo do DNA eucarioto, incluindo os telômeros. A RPA-1 é parte de um complexo heterotrimérico conservado nos eucariotos, incluindo Leishmania spp.. Recentemente nós mostramos por modelagem molecular que a estrutura terciária da LaRPA-1 difere dos seus ortólogos em humanos e leveduras, além de mostrar interações específicas nos telômeros dos parasitos, que na ausência de homólogos canônicos para telomere-end binding protein (TEP) elegem a LaRPA-1 como um potencial candidato para essa função. Neste trabalho, avaliamos a capacidade da LaRPA-1 como uma TEP, cujo papel principal é proteger a extremidade 3' dos telômeros de ataques por exonucleases. Uma busca estrutural por proteínas que compartilham com as TEP domínios de interação proteína-DNA, mostrou que no genoma de Leishmania spp. não existem homólogos estruturais para as mesmas. Aqui mostramos por diferentes abordagens que a LaRPA-1 tem a capacidade de interagir com no mínimo uma repetição telomérica e também é capaz de proteger in vitro a simples fita telomérica rica em G (5’ TTAGGG 3’) da digestão por Exonuclease I bacteriana cuja atividade é no sentido 3’-5’. Somando esses dados, com dados anteriores que mostram que a LaRPA-1 tem preferência pela fita telomérica rica em G e o fato dela ter sido co-purificada com a atividade de telomerase sugerem fortemente que ela está diretamente relacionada com a manutenção da maquinaria telomérica, podendo inclusive ser considerada a principal ligante de simples fita telomérica rica em G (3’ G-overhang) em Leishmania spp. / Among the protozoa parasites of the Leishmania genus are the causative agents of leishmaniasis, a neglected tropical disease endemic in many countries, including Brazil. Disease control and treatment are still inefficient and parasite drug resistance is a challenge. Therefore, efforts for the establishment of intensive research to better understand the molecular biology of these parasites are encouraged. One possible strategy is to study parasite telomeres, a vital chromosome structure important to maintain genome homeostasis. Telomeres are significantly different from the rest of the chromosome and are associated with proteins involved in their maintenance. Replication Protein A subunit 1 (RPA1), a single-stranded DNA-binding protein that plays multiple roles in eukaryotic DNA metabolism, including telomeres, is part of a conserved heterotrimeric complex which is present in most eukaryotes including Leishmania spp. Recently, using molecular dynamics simulations we have shown that the tertiary structure of LaRPA-1 differs from human and yeast RPA-1 and that it also shows parasitespecific interactions with telomeric DNA. In the absence of real homologues to telomere-end binding proteins, LaRPA-1 could be considered a potential candidate. If LaRPA-1 is a telomere-end binding protein, one of its main role would be to protect the telomeric 3`-end termini from nuclease attack. A structural search for proteins that share with the TEP domains of protein-DNA interaction, showed that in the genome of Leishmania spp. there are no structural homologues for them. In this work, we show by different methods, that in vitro LaRPA-1 can bind at least one telomeric repeat and it can also protect the telomeric G-rich sequence (5’ TTAGGG 3’) from the bacterial 3’-5’Exonuclease I digestion. These data compiled to previous data showing that LaRPA-1 preferentially binds the G-rich telomeric DNA and that it co-purifies with telomerase activity strongly suggest that LaRPA-1 is directly involved with parasite telomere maintenance and, possibly, is the main G-rich single-stranded (3’ G-overhang) telomere-binding protein in Leishmania spp.
562

Organizational politics in the front end of innovation : What types of organizational politics can be identified in the front end of innovation - an explorative study

Oskarsson, Steinthor, Nilsson, Linda January 2012 (has links)
New product development (NPD), represent a valuable source for companies’ futuresustainability and development. Previous literature underline the importance of managing theearly period of NPD, since this can increase the performance and consequently reduce theproducts time to market. Organizational politics is present during the whole innovation process,but especially in the front end where there is uncertainty or dissent about choices. For thisreason, contributing a developed understanding of organizational politics within the front end ofinnovation (FEI), is the aim of this study.The theoretical framework of this study combines prior theories that relate to the organizationalpolitics. The structure of it is based on two elements referring to the individual- and theorganizational elements. Organizational elements can further be particularised to structural- andstrategical elements.A qualitative study and a research design with six interviews, where conducted in six innovativefirms of all size. This choice of methodology reflects the explorative purpose of this research.The empirical data are only primary data, collected during the interviews with Research andDevelopment (R&D) managers and R&D subordinates.The analysis of empirical findings revealed relevant conclusions, which can bring value to theresearch area, and also to the practice. Our findings show that diverse sources of organizationalpolitics can be identified in the front end of innovation. Organizational politics both on theindividual and organizational level are identified. Further its we find that informal and formalpower is distributed both in the organizational level and the individual level.The study’s practical relevance consists in the advices and implications to decision makers ofinnovative companies and managers within R&D. By identifying and increasing knowledge inthe field of organizational politics in the front end of innovation, organizations can make frontend activities more efficient and therefore obtain competitive advantages. The theoreticalimplications reflect the organizational politics in the area of the FEI.
563

Intensive Care Nurses' Meaningful Experiences in Providing End-of-Life Care

Stokes, Heather January 2018 (has links)
End-of-life care (EOLC) has become a significant area of expertise in the intensive care unit (ICU). Critical care nurses are the primary caregivers of patients in the ICU and they provide EOLC for patients and families daily. Nurses have portrayed EOLC as difficult and demanding work; yet, they have also described their experiences of providing EOLC as rewarding, gratifying, and a privilege. The purpose of this study was to explore nurses’ meaningful experiences with providing EOLC for patients and families in the context of the ICU. Van Manen’s approach to interpretive phenomenology was used. Unstructured face-to-face interviews were conducted with six registered nurses who were employed in a medical/surgical tertiary care ICU. The interviews were audio-recorded, transcribed, and analyzed. The essence of nurses’ meaningful experiences in providing EOLC was ‘being able to make a difference’. For the nurses, being able to make a difference reflected their efforts to create a good death for the dying patient and their family. The nurses had to navigate a variety of challenges that affected the creation of a good death, however, they made it work by building relationships quickly with families, taking care of themselves, and recognizing it’s a privilege to provide EOLC. These research findings contribute to an expanding body of knowledge and understanding with regards to nurses’ role with the provision of EOLC in the ICU.
564

Modelling and Performance Analysis of New Coolstreaming for P2P IPTV

Raghvendra, Potnis Varada January 2012 (has links) (PDF)
Peer to peer networks are becoming increasingly popular among Internet users as the downloading peers share the storage and upload bandwidth load of the system. This makes it possible for a large number of users to share a data file available at a server without the server upload bandwidth becoming a bottleneck. The P2P technology is being widely used not only for file sharing but also for video on demand, live streaming and IPTV. The delay deadlines are more stringent in live streaming and IPTV than those in file sharing as the traffic is real time. The performance perceived by a user depends upon whether the video stream is being downloaded at the streaming rate. Coolstreaming is the first large scale P2P IPTV system. We model the multi-channel Coolstreaming system via an open queueing network. The peer dynamics at a channel is modelled by a closed queueing network working at a faster rate. We compute the expected number of substreams in the overlay of New Coolstreaming which are not being received at the proper rate. The computation of the Markov chain with a very large state space is handled using the two time scale decomposition. Further we characterize the end to end delay encountered by a video stream originating from the server and received at a user of New Coolstreaming. Three factors contribute towards the delay. The first factor is the mean path length in terms of overlay hops of the partnership graph. The second factor is the mean number of routers between any two overlay peers in the network layer and the third factor is the queueing delay at a router in the Internet. The mean shortest path length in terms of overlay peers in the New Coolstreaming graph is shown to be O(logn)where nis the number of peers in the overlay. This is done by modelling the overlay by a random graph. The mean shortest path in terms of routers in the Internet’s router level topology is seen to be at most O(logNI)where NIis the number of routers in the Internet. We also discuss a method by which we can get the mean delay at a router in the Internet. Thus, the mean end to end delay in New Coolstreaming is shown to be upper bounded by O(lognlogNIE[W])where E[W]is the mean delay at a router in the Internet.
565

Skapandet av en webbaserad informationsplattform : Designprocess från koncept till slutprodukt / The creation of a web based information platform : Design process from concept to final product

Norén, Jonathan January 2012 (has links)
Jag kommer i denna uppsats beskriva den designprocess som pågått vid skapandet av en webbaserad informationsplattform från koncept till slutprodukt. Mitt uppdrag har varit att effektivisera en webbyrås nuvarande sätt att hantera och sprida information på, som bestod av en blandning mellan digital och analog information, och skapa en ny webbaserad informationsplattform. Den nya webbaserade informationsplattformen ska kunna samla all information på en plats och skapa ett effektivare informationsutbyte mellan de anställda på företaget. Jag har använt mig av två teoretiska ramverk; Nielsens tio heuristics samt Krugs visuella design hierarki. Jag har arbetat nära beställaren för att kunna skräddarsy webbplatsen till deras behov. Resultatet efter ett omfattande arbete med designmallar och front-end kodning blev grunden för webbyråns webbaserade informationsplattform, utvecklad för att effektivisera spridningen av information på företaget. / In this essay I will describe the design process during the creation of a web-based information platform, from concept to final product. My assignment has been to take a web agency’s current way of managing and distributing information, which consisted of a mix between digital and analog information, and create a new web-based information platform. The new web-based information-platforms purpose is to gather all information in one place for easier exchange of information between employees at the company and make it more efficient. I used two theoretical frameworks as a theoretical base working on the project; Nielsen's ten heuristics and Krugs visual design hierarchy. I have worked closely with the client to customize the platform to their needs. The result after extensive work with design templates and front-end coding became the foundation for the web agency’s web-based platform, developed to distribute information more efficiently within the agency.
566

Ultra-Low Power RFIC Solutions for Wireless Sensor Networks / Conception de frontaux RF à très faible consommation

Kraimia, Hassen 10 July 2013 (has links)
Depuis leur émergence, les réseaux de capteurs sans fil (WSN) n’ont cessé de se développer devenant un acteur clé dans de nombreuses applications telles que le suivi militaires, la surveillance à distance, la bio-détection et de la domotique. Ces réseaux sont basés sur la norme IEEE 802.15.4 qui est dédié aux réseaux personnels sans fil à faible débit (LR-WPAN) dans la bande de fréquences radio sans licence (868MHz/915MHz/2.4GHz). Faible consommation d'énergie, faible coût de mise en œuvre et le niveau élevé d'intégration sont les principaux défis de ces systèmes. L’émetteur-récepteur est le bloc qui consomme le plus d’énergie dans un nœud capteur, ainsi, la consommation d'énergie du frontal radiofréquence (RFFE) doit être réduite. Pour ce faire, plusieurs approches sont possibles, que ce soit au niveau circuit en enquêtant sur les modes de fonctionnement du transistor ou bien en combinant les fonctionnalités des blocs radiofréquences. Une autre stratégie est d’investiguer le niveau système en proposant de nouvelles architectures de démodulation. Cette thèse explore les exigences et les défis spécifiques pour la conception de circuits intégrés radiofréquences (RFIC) ultra-basse consommation pour les réseaux de capteurs sans fil. Ces travaux ont abouti à la conception d'un démodulateur compact réalisé dans une technologie CMOS 65nm et qui est compatible avec tous les types de modulation. / Since their emergence, Wireless Sensor Networks (WSN) have been growing continually becoming a key player in many applications such as military tracking, remote monitoring, bio-sensing and home automation. These networks are based on IEEE 802.15.4 standard which is dedicated to low rate wireless personal area networks (LR-WPANs) in the unlicensed radio band (868MHz/915MHz/2.4GHz). Low power consumption, low cost of implementation and high level of integration are the main challenges of these systems. As radio frequency transceiver is one of the most power hungry block in wireless sensor node, power consumption of radio frequency front-end (RFFE) must be reduced. To deal with, several approaches are possible, either at circuit level by investigating operating modes of transistors and merging functionalities or at system level by searching novel demodulation architecture. This thesis explores the specific requirements and challenges for the design of ultra-low power radio frequency integrated circuits (RFICs), leading to the design of a compact demodulator implemented in 65 nm CMOS technology and compatible with all modulation schemes.
567

OFFLINE SCHEDULING OF TASK SETS WITH COMPLEX END-TO-END DELAY CONSTRAINTS

Holmberg, Jonas January 2017 (has links)
Software systems in the automotive domain are generally safety critical and subject to strict timing requirements. Systems of this character are often constructed utilizing periodically executed tasks, that have a hard deadline. In addition, these systems may have additional deadlines that can be specified on cause-effect chains, or simply task chains. They are defined by existing tasks in the system, hence the chains are not stand alone additions to the system. Each chain provide an end-to-end timing constraint targeting the propagation of data through the chain of tasks. These constraints specify the additional timing requirements that need to be fulfilled, when searching for a valid schedule. In this thesis, an offline non-preemptive scheduling method is presented, designed for single core systems. The scheduling problem is defined and formulated utilizing Constraint Programming. In addition, to ensure that end-to-end timing requirements are met, job-level dependencies are considered during the schedule generation. Utilizing this approach can guarantee that individual task periods along with end-to-end timing requirements are always met, if a schedule exists. The results show a good increase in schedulability ratio when utilizing job-level dependencies compared to the case where job-level dependencies are not specified. When the system utilization increases this improvement is even greater. Depending on the system size and complexity the improvement can vary, but in many cases it is more than double. The scheduling generation is also performed within a reasonable time frame. This would be a good benefit during the development process of a system, since it allows fast verification when changes are made to the system. Further, the thesis provide an overview of the entire process, starting from a system model and ending at a fully functional schedule executing on a hardware platform.
568

Perceptions of Wooden Multifamily Houses : Applying an Extended Association Pattern Technique

Schauerte, Tobias January 2006 (has links)
During the past years, wooden one and two family houses showed a higher growth rate on the German construction market compared to conventional material like brick and stone. Wood as construction material became more and more attractive. Furthermore, a growing demand on multifamily houses could be recognized, yet, wood has not been considered as an alternative in this field of application until now. Trying to understand the end-users attitudes towards wooden multifamily houses, this licentiate thesis aims at exploring German end-users’ perceptions of wooden multifamily houses. To collect the necessary data, the Association Pattern Technique (APT) was applied, which is a two-stage method and has its foundations in the Means-End theory. In the first stage, 31 in-depth laddering interviews were carried out, which served as the base for the matrix-survey in the second stage, where 229 answers were received. Extending the existing method in the matrix-survey stage allowed for important additional data to be uncovered. The results show that individuals associate certain product attributes with wooden multifamily houses and that these attributes are thought to entail specific consequences. These consequences are in turn linked with the personal values of the respondents. The most dominant perceptual orientations of different groups of respondents are shown and significant differences could be found in how individuals in German perceive wooden multifamily houses depending on age, income and habitation.
569

End-to-end Security Enhancement of an IoT Platform Using Object Security

Tjäder, Hampus January 2017 (has links)
The Internet of Things (IoT) is seen as one of the next Internet revolutions. In a near future the majority of all connected devices to the Internet will be IoT devices. These devices will connect previously offline constrained systems, thus it is essential to ensure end-to-end security for such devices. Object Security is a concept where the actual packet or sensitive parts of the packet are encrypted instead of the radio channel. A compromised node in the network will with this mechanism still have the data encrypted ensuring full end-to-end security. This paper proposes an architecture for using the object security format COSE in a typical constrained short-range radio based IoT platform. The IoT platform utilizes Bluetooth Low Energy and the Constrained Application Protocol for data transmission via a capillary gateway. A proof-of-concept implementation based on the architecture validates that the security solution is implementable. An overhead comparison between current channel security guidelines and the proposed object security solution results in a similar size for each data packet. The thesis concludes that object security should be seen as an alternative for ensuring end-to-end security for the Internet of Things.
570

High-performance near-time processing of bulk data

Swientek, Martin January 2015 (has links)
Enterprise Systems like customer-billing systems or financial transaction systems are required to process large volumes of data in a fixed period of time. Those systems are increasingly required to also provide near-time processing of data to support new service offerings. Common systems for data processing are either optimized for high maximum throughput or low latency. This thesis proposes the concept for an adaptive middleware, which is a new approach for designing systems for bulk data processing. The adaptive middleware is able to adapt its processing type fluently between batch processing and single-event processing. By using message aggregation, message routing and a closed feedback-loop to adjust the data granularity at runtime, the system is able to minimize the end-to-end latency for different load scenarios. The relationship of end-to-end latency and throughput of batch and message-based systems is formally analyzed and a performance evaluation of both processing types has been conducted. Additionally, the impact of message aggregation on throughput and latency is investigated. The proposed middleware concept has been implemented with a research prototype and has been evaluated. The results of the evaluation show that the concept is viable and is able to optimize the end-to-end latency of a system. The design, implementation and operation of an adaptive system for bulk data processing differs from common approaches to implement enterprise systems. A conceptual framework has been development to guide the development process of how to build an adaptive software for bulk data processing. It defines the needed roles and their skills, the necessary tasks and their relationship, artifacts that are created and required by different tasks, the tools that are needed to process the tasks and the processes, which describe the order of tasks.

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