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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.
81

Interferon induction by paramyxoviruses : investigations into specific RNA:protein interactions

Dominguez Palao, Francisco January 2017 (has links)
RNA:protein interactions are central in many cellular processes, including activation of innate immune responses against microbial infection. Their study is essential to better understand the diverse biological events that occur within cells. However, isolation of RNA:protein complexes is often laborious and requires specialized techniques. This thesis is concerned with attempts to develop an improved purification protocol to isolate specific RNA:protein complexes. Taking advantage of the specific interaction of the Pseudomonas aeruginosa PP7 protein with its cognate RNA binding site, termed the PP7 recognition sequence (PRS), the aim was to identify cellular proteins involved in activating cell-signalling pathways, including the interferon-induction cascade, following viral infection with stocks of parainfluenza virus 5 (PIV5) rich in copyback defective interfering (DI) particles. Copyback DI genomes are powerful inducers of IFN and, here, I show they also activate the induction of IL-6, IL-8 and TNFα; cytokines that also have antiviral properties. Following the successful cloning of the PRS into a copyback DI genome, we investigated conditions for optimal in vitro capture of DI-PRS:protein complexes by PP7 on Dynabeads. When tested, the protocol led to the successful capture of ILF3 and PKR, two dsRNA binding proteins induced by IFN. We further developed a tap-tagging system to minimize the presence of non-specifically bound proteins to Dynabeads that may interfere with future mass spectrometry analysis. To isolate DI-PRS RNA:protein complexes from infected cells, attempts were made to rescue replicating DI-PRS genomes in the context of wild type PIV5. Similarly, efforts were made to isolate influenza A virus RNPs that contained the PRS in the neuraminidase (NA) gene from infected cells using the PP7-based protocol developed. However, for reasons discussed, unfortunately RNA:proteins complexes were not successfully purified from infected cells in either case.
82

Självkänsla : En studie om barns självkänsla i förskolan / Self-esteem : A study of childrens self-esteem in preschool

Rosenius, Maria January 2018 (has links)
Syftet med studien var att belysa hur förskollärare definierar självkänsla och hur de beskriver självkänslans betydelse för individen. Min avsikt var också att skapa en förståelse för hur arbetet i verksamheten kan påverka barns självkänsla. Studien utgick från Daniel Sterns utvecklingspsykologiska teori och RIGs samt affektintoning. Även det sociokulturella perspektivet och Hundeides kontrakt och metakontrakt var en utgångspunkt i studien. Dessa båda beskriver hur varje interaktion eller samspel bidrar till individens självförståelse. För att besvara studiens syfte genomfördes fyra kvalitativa intervjuer. Informanterna var alla förskollärare som genom sin utbildning har ett ansvar över att arbetet på förskolan sker i enlighet med läroplanen. Intervjusvaren analyserades genom att meningen i informanternas svar tolkades, och reducerades till några kategorier som sorterades under respektive forskningsfråga. Studiens resultat visade att förskollärarna i stor utsträckning definierar självkänsla som något inre, som är kopplat till grundtrygghet och positiv värdering av sig själv. Förskollärarnas beskrivningar av självkänslans betydelse för individen kan förstås ha både kortsiktiga och långsiktiga effekter för individen. Resultatet ger möjlighet att förstå att arbetet i verksamheten ofta fungerar stärkande för barns självkänsla på olika sätt.
83

Modelling of Test Bench for Road Load Simulation

Åberg Skender, Dennis January 2017 (has links)
Warehouse forklifts are often powered by batteries. By using a test bench where the forklift can be driven in a certain driving-cycle, the battery capacity can be tested. To obtain the same speed curve on the test bench as a forklift obtains when driving on a real road, the test bench must be able to simulate road load. In this master’s thesis, a test bench is modelled in Simulink using grey-box modelling and validated with measured data. Also, a speed regulator is developed and implemented in the test bench model to simulate road load. Simulations with the model and the speed regulator show high accuracy when compared against measured data. However, the results show that the pre-attached torque sensor is not optimally located, and that the gear oil temperature is of interest to measure to be able to model the friction torque as a function of the temperature. / Lagertruckar drivs ofta av batterier. Batterikapaciteten kan testas genom att använda en testbänk där trucken körs i en körcykel. För att simulera samma hastighetskurva på testbänken som trucken erhåller vid riktig körning på väg måste testbänken kunna simulera vägmotstånd. I detta examensarbete modelleras en testbänk i Simulink genom grey-box modellering och valideras med uppmätt data. Även en hastighetsregulator utvecklas och implementeras i modellen för att simulera vägmotstånd. Simuleringar med modellen och hastighetsregulatorn visar på hög träffsäkerhet jämfört med uppmätt data. Resultaten visar dock på att den monterade momentsensorn inte är optimalt belägen och att växeloljans temperatur är av intresse att mäta för att kunna modellera friktionen som en funktion av temperaturen.
84

Modelling and Analysis of a Screw Joint Test Rig

Fallsberg, Beatrice January 2017 (has links)
Today, tightening tools are widely used in the industry and on the market you will find several products that have been assembled with the help of tightening tools. For example, tightening tools are used in the automotive industry and when assembling computer hardware. It is important that the tightening tools are robust and of high quality in order to fulfil the demanded requirements. High assembly speed has entailed an extensive use of tightening tools. To ensure that the tightening tools have the desired properties, tightening tools are tested continuously using so-called test systems. This puts high demands on the test systems since it is of importance that the tightening tools can be tested in a simple, fast and reliable way as well as repeatedly. Therefore, Atlas Copco would like to investigate whether a test system constructed with an electrical motor is a good choice. The idea of this thesis is to investigate possibilities and limitations in a test system consisting of an electrical motor that emulates the behaviour of a screw joint. To be able to investigate hardware limitations a test rig is constructed and then modelled in MATLAB. Further, simulations have been carried out in order to analyse the possibilities and limitations of such a test rig. The conclusion is that the implemented LQ controller seems to be able to control the braking motor sufficiently like a screw joint.
85

Evaluating the repeatability of friction and wear testing on a lubricant with dispersed hexagonal-boron nitride nanoparticles

Benadé, Howard P. January 2015 (has links)
The SRV test rig was used to evaluate the friction and wear properties of a lubricant in a laboratory setup. Normally, the coefficient of friction and the amount of wear that occurred are measured while the wear scar surface is also evaluated. Special attention was paid to factors that affect the repeatability. The test fluid was subjected to a friction and wear test on the SRV test rig in order to determine what factors affect the repeatability of the coefficient of friction, the amount of wear that occurred and the wear scar appearance. The test fluid used was based on rapeseed oil and white mineral oil. The fluid also contained an extreme pressure additive in the form of sulphurised ester. This was also compared for the same test fluid with dispersed hexagonal-boron nitride (h-BN) nanoparticles. The standard test method as described by ASTM D 6425, was used as test method. Instead of the standard temperature, the block temperature was increased to 100 °C in order to simulate harsher operating environments. The load was set at 200 N It was found that:  The rapid load increase from 50 to 200 N at the end of the running-in period (as described in the standard test method) caused poor repeatability. The test was modified with a more gradual load application for the duration of the running-in period (30 N/min), which resulted in improvement in the repeatability of the tests conducted.  The moisture content in the atmosphere also affected the repeatability of the friction and wear tests. This was most likely due to the formation of a corrosion layer that involves water and by keeping the relative humidity constant, a further improvement in the repeatability was observed. The addition of the h-BN nanoparticles resulted in an improvement of the repeatability of the coefficient of friction (COF), wear scar surface (WSS) and wear scar volume (WSV), since the wear scar surfaces indicated that the particles remove the corrosion layers. This could have led to more consistent wear surfaces for the duration of the test.  The particles also influenced the corrosion layer formation. For both fluids, Raman spectroscopy indicated that greigite (Fe3S4) and goethite (α-FeOOH) were found on the surface, while additional corrosion products were found on the wear scar surface for the test fluid with dispersed particles. These compounds were melanterite (FeSO4.7H2O) and rozenite (FeSO4.4H2O). All these corrosion products were most likely formed due to the reaction of iron from the specimens with sulphurised esters in the test fluid. / Dissertation (MEng)--University of Pretoria, 2015. / tm2015 / Chemical Engineering / MEng / Unrestricted
86

Constitutive RIG-I activation causes skin lesion resembling psoriasis in transgenic mice / 恒常的活性型RIG-Iのマウスへの遺伝子導入は乾癬様の皮膚炎の原因となる

Ahmed, S.A. Abu Tayeh 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(生命科学) / 甲第23335号 / 生博第453号 / 新制||生||60(附属図書館) / 京都大学大学院生命科学研究科統合生命科学専攻 / (主査)教授 野田 岳志, 教授 杉田 昌彦, 教授 千坂 修 / 学位規則第4条第1項該当 / Doctor of Philosophy in Life Sciences / Kyoto University / DFAM
87

Návrh stavu pro dlouhodobé testování pryžových segmentů / Test Rig Design for Durability Testing of the Rubber Segments

Borek, Vojtěch January 2019 (has links)
The aim of diploma thesis is construction design of test rig for durability testing of the rubber segments. The work contains a brief description of tested component, test rigs and individual parts of the testing system. Next chapter describes conception and construction solutions with justification of choice specific parts, supported by analysis of critical parts. Finally the overall construction design is evaluated and accompanied with a documentation of drawings, which is attached to the thesis.
88

Tankovací a osvětlovací věž pro závody GT automobilů / Petrol station and lighting tower for races of GT cars

Nakládal, Tomáš January 2008 (has links)
The aim of this diploma work is an engineering design of technical set of equipment for endurance racing according with FIA regulations. Equipment of pit box should assure: refueling, lighting place of pit box and distribution of compressed air. CAD model of box equipment is designed in SolidWorks 2007 software. Construction is verified by the help of finite element method (FEM) in ANSYS WORKBENCH software. Main emphasis is attached to functionality, variability and low prize of this solution.
89

Rekonstrukce stanice pro testování převodovek / Reconstruction of Gearbox Testing Rig

Rozsypálek, Tomáš January 2013 (has links)
The aim of this diploma thesis is reconstruction of gearbox testing rig. Modernization will allow fully automatic long-term gearbox tests according to pre-defined test parameters. The first part of thesis describes commercial and scientific solutions of used testing rigs. Individual solutions are inspected and evaluated for applicability to upgrade the testing rig. The second part of diploma thesis deals with selection of purchased components for allowing automatic drive, design concepts, selection of appropriate design, assembly and installation of control board and calibration of used components. This part of diploma thesis deals with analysing of software solution made for automatic drive too. The output of this work is a functional sample of control hardware and software for automatic and manual control which contains recording of measured data.
90

Rekonstrukce stanice AXMAT / Reconstruction of AXMAT Testing Station

Gergel, Matej January 2014 (has links)
The master´s thesis deals with reconstruction of RCF test rig AXMAT. Main goal is design new hydraulic load system and his realization. The first part of thesis describes similar experimental machines and their pros and cons. This analysis is base for complete reconstruciton of AXMAT. New hydraulic load system allows dynamic programmable load cycles. Control system with close loop and feedback was created in software Matlab – Simulink. Main frame was reconstructed too. Control and action parts were asseble to station. Output of thesis is function sample.

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