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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.
101

Effets des entrées énergétiques sur les composés azotés dans la haute atmosphère de la Terre / Energetic inputs effects on nitrogen compounds in Earth's upper atmosphere

Vialatte, Anne 09 October 2017 (has links)
La météorologie de l’espace est un domaine dédié à l’étude de l’impact des variations de l’activité solaire sur l’environnement spatial de la Terre. Celles-ci peuvent avoir des conséquences importantes sur les technologies humaines, comme les réseaux de lignes haute-tension ou les systèmes de télécommunication par satellites. Ces mêmes variations sont également à l’origine des aurores, phénomènes observés dans la haute atmosphère de la Terre au niveau des pôles, au pied des lignes de champ magnétique. Elles vont pouvoir nous servir de traceur dans l’étude des particules so- laires piégées dans l’environnement spatial de notre planète.Les émissions aurorales, complexes, de part leur étalement et différen- ciation en altitude et de leur diversité spectrale, restent un challenge ob- servationnel.Les émissions atomiques aurorales sont bien documentées, mais ce n’est pas toujours le cas des émissions moléculaires, qui sont pourtant une source d’information potentielle sur les précipitations énergétiques prove- nant de la magnétosphère. C’est dans ce contexte que se place la définition de la mission du nanosatellite ATISE (Auroral Thermospheric and Ionosphe- ric Spectrometer Experiment), développé au Centre Spatial Universitaire de Grenoble. Il aura pour but l’observation de la haute atmosphère terrestre via l’acquisition de spectres dans le proche UV et le visible.Le diazote N2 et son ion N2+ font partie des composés majoritaires de l’atmosphère, et sont donc un choix cohérent afin de définir l’observabilité des émissions moléculaires. Le monoxyde d’azote NO est une espèce mino- ritaire dans la thermosphère, mais va avoir un rôle clé dans la destruction d’ozone stratosphérique, et donc dans la problématique du dérèglement climatique.Les émissions de ces composés, et notamment leurs profils verticaux ainsi que intensités ont été étudiées grâce au modèle TRANS, qui résout l’équation de Boltzmann pour le transport d’électrons. Ceci nous a aidé à caractériser les besoins scientifiques de la mission ATISE. Dans un second temps, l’analyse des résultats du démonstrateur-sol de ce nanosatellite a montré le potentiel de cette mission, bien que certaines spécifications ne soient pas encore atteintes. Enfin, toujours dans cette logique de recherche de nouvelles quantités observables pour la météorologie de l’espace, une dernière partie abordera la polarisation de la lumière aurorale, avec l’étude de la bande à 427,8 nm de N2+ . / Space weather is the study of the Solar activity’s impact on Earth’s space environment. This is relevant as it may have serious consequences over modern technology, such as high-voltage power lines grids or telecommu- nication systems via satellites. Solar activity is also the phenomenon that causes the aurorae, which can be seen in Earth’s upper atmosphere, at the poles, at the base of magnetic field lines. Due to this aurorae may be used as a proxy for the study of Solar particles trapped in Earth’s magnetic field.Auroral emissions are complex, as they are spread over various altitudes and wide spectral ranges. Therefore, they remain an observational chal- lenge.Emissions from atomic lines transitions in aurorae are well documented and understood, but this is not always the case for molecular emissions. These are a potential source of information on energetic inputs from the magnetosphere. This is the context in which the ATISE (Auroral Thermo- spheric and Ionospheric Spectrometer Experiment) nanosatellite was designed in the Grenoble University Space Center. Its purpose will be to observe Earth’s upper atmosphere through the acquisition of spectra in near-UV and visible domains.Dinitrogen N2 and its ion N2+ are major components of Earth’s atmos- phere at larges altitudes, and therefore a logical choice in order to define molecular emission observability. On the other hand, nitrogen monoxide NO is a minor component in the thermosphere, but has a key role in stra- tospheric ozone destruction, and therefore has important consequences on the climate.Auroral emissions, and more particularly their vertical profiles and in- tensities were studied with the TRANS model, which solves the Boltzmann equation for electron transport in the atmosphere. We used these results to define the scientific requisites for the ATISE mission. In a second phase, we tested and analyzed the results of a ground demonstrator of the instru- mentation that will be found in the nanosatellite. It showed great potential, despite the fact that part of the specifications are not yet fulfilled. Finally, still looking for new observables quantities for space weather, we studied the polarisation of auroral light, with a focus on the 427,8 nm band of N2+.
102

Galna män av kvinnliga genier : –En studie av gotiska genrekonventioner i Aurora Ljungstedts Hin Ondes Hus och Lucie Lagerbielkes En Sällsam Upplefvelse

Almer, Desirée January 2018 (has links)
Primärkällorna utgörs av de två skönlitterära verken Hin Ondes Hus (1853) av Aurora Ljungstedts och En Sällsam Upplefvelse (1913) av Lucie Lagerbielke. De båda verken har en anknytning till några av gotikens centralfigurer och förhåller sig på olika sätt till gotikens genrekonventioner. Undersökningen syftar till att utreda vilken funktion verkens författare har låtit det explicita inflytandet av den gotiska strömningen fylla och hur förhållningssättet till gotiklitteraturens klassiska genrekonventioner kommer till uttryck. Metoden är komparativ där gotiska motiv urskiljs och redogörs för. Den teoretiska utgångspunkten är en genrediskussion utifrån Yvonne Leffler respektive Mattias Fyhrs definitioner av gotik och vilka komponenter som krävs i ett verk för att bestämma genretillhörighet. Analysens resultat visar att författarna låtit inflytandet av den gotiska strömningen fylla olika typer av funktioner. Där Ljungstedt följt de klassiska genrekonventionerna i större utsträckning och låtit verket syfta till att frambringa den njutbara rysningen. Lagerbielke å andra sidan har ett annat ändamål och budskap med sitt verk, men följer också i stor utsträckning de klassiska gotiska genrekonventionerna.
103

Co-targeting aurora kinase with PD-L1 and PI3K abrogates immune checkpoint mediated proliferation in peripheral T-cell lymphoma: a novel therapeutic strategy

Islam, Shariful, Vick, Eric, Huber, Bryan, Morales, Carla, Spier, Catherine, Cooke, Laurence, Weterings, Eric, Mahadevan, Daruka 01 November 2017 (has links)
Peripheral T-cell non-Hodgkin lymphoma (PTCL) are heterogeneous, rare, and aggressive diseases mostly incurable with current cell cycle therapies. Aurora kinases (AKs) are key regulators of mitosis that drive PTCL proliferation. Alisertib (AK inhibitor) has a response rate similar to 30% in relapsed and refractory PTCL (SWOG1108). Since PTCL are derived from CD4(+)/CD8(+) cells, we hypothesized that Program Death Ligand-1 (PDL1) expression is essential for uncontrolled proliferation. Combination of alisertib with PI3K alpha (MLN1117) or pan-PI3K inhibition (PF-04691502) or vincristine (VCR) was highly synergistic in PTCL cells. Expression of PD-L1 relative to PD-1 is high in PTCL biopsies (similar to 9-fold higher) and cell lines. Combination of alisertib with pan-PI3K inhibition or VCR significantly reduced PD-L1, NF-kappa B expression and inhibited phosphorylation of AKT, ERK1/2 and AK with enhanced apoptosis. In a SCID PTCL xenograft mouse model, alisertib displayed high synergism with MLN1117. In a syngeneic PTCL mouse xenograft model alisertib demonstrated tumor growth inhibition (TGI) similar to 30%, whilst anti-PD-L1 therapy alone was ineffective. Alisertib + anti-PD-L1 resulted in TGI > 90% indicative of a synthetic lethal interaction. PF-04691502 + alisertib + anti-PD-L1 + VCR resulted in TGI 100%. Overall, mice tolerated the treatments well. Co-targeting AK, PI3K and PD-L1 is a rational and novel therapeutic strategy for PTCL.
104

Chemical Genomics Approach Leads to the Identification of Hesperadin, an Aurora B Kinase Inhibitor, as a Broad-Spectrum Influenza Antiviral

Hu, Yanmei, Zhang, Jiantao, Musharrafieh, Rami, Hau, Raymond, Ma, Chunlong, Wang, Jun 08 September 2017 (has links)
Influenza viruses are respiratory pathogens that are responsible for annual influenza epidemics and sporadic influenza pandemics. Oseltamivir (Tamiflu((R))) is currently the only FDA-approved oral drug that is available for the prevention and treatment of influenza virus infection. However, its narrow therapeutic window, coupled with the increasing incidence of drug resistance, calls for the next generation of influenza antivirals. In this study, we discovered hesperadin, an aurora B kinase inhibitor, as a broad-spectrum influenza antiviral through forward chemical genomics screening. Hesperadin inhibits multiple human clinical isolates of influenza A and B viruses with single to submicromolar efficacy, including oseltamivir-resistant strains. Mechanistic studies revealed that hesperadin inhibits the early stage of viral replication by delaying the nuclear entry of viral ribonucleoprotein complex, thereby inhibiting viral RNA transcription and translation as well as viral protein synthesis. Moreover, a combination of hesperadin with oseltamivir shows synergistic antiviral activity, therefore hesperadin can be used either alone to treat infections by oseltamivir-resistant influenza viruses or used in combination with oseltamivir to delay resistance evolution among oseltamivir-sensitive strains. In summary, the discovery of hesperadin as a broad-spectrum influenza antiviral offers an alternative to combat future influenza epidemics and pandemics.
105

Stadsnära Norrskensturism : Viktiga parametrar gällande artificiell belysning för utvecklingen av norrskensturism i ett stadsnära läge / Northern Light tourism in an urban environment : Important aspects of the artificial lighting regarding the development of northern light tourism in an urban environment

Petersson, Rasmus, Tigerstrand, Rex January 2020 (has links)
Enligt Tillväxtverket (2019) har den totala konsumtionen inom svensk turismnäring ökat med 124% mellan åren 2000–2018. Denna trend kan även utläsas för den svenska naturturismen där en studie från Mittuniversitet (2014) visade att det inom naturturism omsätts ca 3.6 miljarder kronor varje år och att 40% av företagen var i en tillväxtfas (Fredman, Margaryan, 2014). En form av naturturism som växt sig stark norra Sverige under senare år är norrskenturismen (Jóhannesson & Lund, 2017; Mathisen, 2017; Friedman, 2010), som i enbart Kiruna kommun beräknas omsätta runt 100 miljoner varje år (Naturturismföretagen. 2019). Idag är denna typ av turism framförallt koncentrerad till landsbygden med långa avstånd och höga resekostnader som följd. Samtidigt som många turister har en negativ påverkan på djur och natur (Björnsdóttir, 2015). Syftet med studien är således att ta fram och föra en diskussion kring vilka aspekter av en belysningsanläggning som är viktiga för att göra norrskensturismen mer stadsnära och tillgänglig för en större del av befolkningen. Arbetet ska även ge förslag på generella anpassningar av den artificiella belysningen som kan appliceras på anläggningen. Metoden som används är en kombination av litteraturstudie, intervjuer och en analys av befintliga belysningsprogram. Litteraturstudien gav en bakgrundsundersökning inom ämnet samt tydliggjorde hur studiens syfte skulle formuleras. Intervjuerna genomfördes med fyra ljusdesigners där deras tankar och idéer gällande vilka aspekter som anses viktiga för att skapa en stadsnära norrskensturism. I studiens sista steg analyserades redan befintliga belysningsprogram från städer där belysningsanläggningen anpassats för att minimera stadens ljusföroreningar. Analyserna gav sedan konkreta åtgärdsförslag som jämfördes med intervjudeltagarnas resonemang. Studiens resultat visar på att armaturavskärmning, ljusfördelning, ljuspunktshöjder och belysningsstyrning anses vara de viktigaste aspekterna för den artificiella belysningen. Lagar, standarder och andra former av styrdokument är en annan aspekt som ofta togs upp, med resonemang för hur dessa kan påverka en belysningsanläggnings hösta respektive lägsta nivå. Gällande de generella förslagen på anpassningar redovisas att både anpassningar av ljuskällors färgtemperaturer och ljusriktning kan appliceras på en anläggning förhållandevis enkelt. Men att en väl anpassad belysningsstyrning är svårare, det ska dock tilläggas att denna anpassning kan ha större och mer positiv påverkan för en norrskensanpassad belysningsanläggning. Till de personer som vill utveckla denna typ av projekt rekommenderas att i ett tidigt skede blanda in eventuella intressenter och ta hänsyn till deras aspekter. Arbetets ämnesområde är relativt outforskat och en väl utförd förstudie inför projektet är därför av stor vikt för att minimera eventuella misstag. Studien begränsas av att enbart ta hänsyn till och föra en diskussion kring de aspekter som uppkommit under intervjuerna. Dessa aspekter är endast hämtade ur en ljusdesigners perspektiv och tydliggör således inte andra intressenters intressen inom ämnet. / According to The Swedish Agency for Economic and Regional Growth (2019) the total consumption of tourism in Sweden has grown with 124% between the years 2000-2018. This trend that also applies for the Swedish nature-tourism where a study from Mid Sweden University (2014) shows that nature-based tourism each year has approximately 3.6 billion SEK in turnover, and that 40% of concerned businesses is in a phase of growth (Fredman & Margaryan, 2014). Northern light-tourism is a form of nature-tourism that has grown quickly in northern Sweden in recent years (Jóhannesson & Lund, 2017; Mathisen, 2017; Friedman, 2010). In Kiruna alone it is estimated that the northern light tourism alone has a revenue of 100 million SEK each year (Swedish Nature and Ecotourism Association, 2019). This form of tourism often has a high traveling costs and is concentrated to the countryside with far traveling distances between each site. In the same time, a lot of tourists on the countryside has a negative impact on the nature and wildlife (Björnsdóttir, 2015). The purpose of this study is therefore to point out and discuss around different aspects concerning the artificial lighting with an impact on how we can develop a northern light- tourism in a more urban environment. The study shall also give general suggestions for how these aspects can be adapted into a light installation. The method that is use in this research is a literature study, interviews and an analyse of four cities’ lighting masterplans. The literature study was used to specify the foundation and aim of the study. Where the interviews clarified the important aspect for an urban development of northern light-tourism from a lighting designers’ point of view. In the last phase of the study, four lighting masterplans with a clear focus on how to prevent light pollution where analysed. These analyses then gave some action proposals that can be compared to the answers from the interview participants. The results from the study show that shielded luminaires, light distributions, luminaire installation height and lighting controls are considered to have the largest impact on the lighting installation regarding the visibility of the northern light. Also, laws and regulations were a common answer, with some reasoning about the regulations of max and min requirements from an installation. Regarding the general proposals some suggestions concerning luminaire colour temperature and light distribution can quite easy be applied to an installation, in comparison to a more complicated lighting control. To everyone that would like to develop a project of this kind it is recommended that in an early stage get in contact with any stakeholders and listen to their opinions. In that way any mistakes are minimised even though the topic of this study is relatively unexplored.The study is limited to only show and discuss the answers that came up under the interviews, and that these answers is only reproduced from a lighting designers’ point of view.
106

Understanding Design Requirements for Building Reliable, Space-Based FPGA MGT Systems Based on Radiation Test Results

Ellsworth, Kevin M. 20 March 2012 (has links) (PDF)
Space-based computing applications often demand reliable, high-bandwidth communication systems. FPGAs with Mulit-Gigabit Transceivers (MGTs) provide an effective platform for such systems, but it is important that system designers understand the possible susceptibilities MGTs present to the system. Previous work has provided a foundation for understanding the susceptibility of raw FPGA MGTs but has fallen short of testing MGTs as part of a larger system. This work focuses on answering the questions MGT system designers need to know in order to build a reliable space-based MGT system. Two radiation tests were performed with a test architecture built on the Aurora protocol. These tests were specifically designed to discover system susceptibilities, and effective mechanisms for upset detection, recovery, and recovery detection. Test results reveal that the Aurora protocol serves as an effective basis for simple point-to-point communication for space-based systems but that some additional logic is necessary for high reliability. Particularly, additional upset detection and recovery mechanisms are necessary as well as additional status indicators. These additions are minimal, however, and not all are necessary depending on system requirements. The most susceptible part of the MGT system is the MGT tile components on the RX data path. Upsets to these components most often results in data corruption only and do not affect system operation or disrupt the communication link. Most other upsets which do disrupt normal system operation can be recovered automatically by the Aurora protocol with built-in mechanisms. Only 1% of observed events in testing required additional recovery mechanisms not supplied by Aurora. In addition to test data results, this work also provides suggestions for system designers based on various system requirements and a proposed MGT system design based on the Aurora protocol. The proposed system serves as an example to illustrate how test data can be used to guide the system design and determine system availability. With this knowledge designers are able to build reliable MGT systems for a variety of space-based systems.
107

Single Event Mitigation for Aurora Protocol Based MGT FPGA Designs in Space Environments

Harding, Alexander Stanley 17 June 2014 (has links) (PDF)
This work has extended an existing Aurora protocol for high-speed serial I/O between FPGAs to provide greater fault recovery in the presence of high-energy radiation. To improve on the Aurora protocol, additional resets that affect larger portions of the system were used. Detection for additional error modes that occurred but were not detected by the Aurora protocol was designed. Radiation testing was performed on the Aurora protocol with the additional mitigation hardware. The test gathered large amounts of data on the various error modes of the Aurora protocol and how the additional mitigation circuitry affected the system. The test results showed that the addition of the recovery circuitry greatly enhanced the Aurora protocol's ability to recover from errors. The recovery circuit recovered from all but 0.01% of errors that the Aurora protocol could not. The recovery circuit further increased the availability of the transmission link by proactively applying resets at much shorter intervals than used in previous testing. This quick recovery caused the recovery mechanism to fix some errors that may have recovered automatically with enough time. However, the system still showed an increase in performance, and unrecoverable errors were reduced 100x. The estimated unrecoverable error rate of the system is 5.9E-07 in geosynchronous orbit. The bit error rate of the enhanced system was 8.47754E-015, an order of magnitude improvement.
108

The Role of LIM Kinase 1 and its Substrates in Cell Cycle Progression

Ritchey, Lisa 01 January 2014 (has links)
LIM Kinase 1 (LIMK1), a modulator of actin and microtubule dynamics, has been shown to be involved in cell cycle progression. In this study we examine the role of LIMK1 in G1 phase and mitosis. We found ectopic expression of LIMK1 resulted in altered expression of p27Kip1, the G1 phase Cyclin D1/Cdk4 inhibitor. Overexpression of LIMK1 resulted in lower levels of p27Kip1 and p27Kip1-pY88 (inactive p27Kip1). Knockdown of LIMK1 resulted in elevated levels of p27Kip1 and p27Kip1-pY88. Together, these results suggest LIMK1 regulates progression of G1 phase through modulation of p27Kip1 expression. LIMK1 is involved in the mitotic process through inactivating phosphorylation of Cofilin. Aurora kinase A (Aur-A), a mitotic kinase, regulates initiation of mitosis through centrosome separation and proper assembly of bipolar spindles. Phosphorylated LIMK1 is recruited to the centrosomes during early prophase, where it colocalizes with ?-tubulin. Here, we report a novel functional cooperativity between Aur-A and LIMK1 through mutual phosphorylation. LIMK1 is recruited to the centrosomes during early prophase and then to the spindle poles, where it colocalizes with Aur-A. Aur-A physically associates with LIMK1 and activates it through phosphorylation, which is important for its centrosomal and spindle pole localization. Aur-A also acts as a substrate of LIMK1, and the function of LIMK1 is important for its specific localization and regulation of spindle morphology. Taken together, the novel molecular interaction between these two kinases and their regulatory roles on one other's function may provide new insight on the role of Aur-A in manipulation of actin and microtubular structures during spindle formation. The substrates of LIMK1, Aur-A and Cofilin, are also involved in the mitotic process. Aur-A kinase regulates early mitotic events through phosphorylation and activation of a variety of proteins. Specifically, Aur-A is involved in centrosomal separation and formation of mitotic spindles in early prophase. The effect of Aur-A on mitotic spindles is mediated by modulation of microtubule dynamics and association with microtubule binding proteins. In this study we show that Aur-A exerts its effects on spindle organization through regulation of the actin cytoskeleton. Aur-A phosphorylates Cofilin at multiple sites including S3 resulting in inactivation of its actin depolymerizing function. Aur-A interacts with Cofilin in early mitotic phases and regulates its phosphorylation status. Cofilin phosphorylation follows a dynamic pattern during progression of prophase to metaphase. Inhibition of Aur-A activity altered subcellular localization of Cofilin and induced a delay in the progression of prophase to metaphase. Aur-A inhibitor also disturbed the pattern of Cofilin phosphorylation, which correlated with the mitotic delay. Our results establish a novel function of Aur-A in the early mitotic stage through regulation of actin cytoskeleton reorganization. ?
109

Cuerpos femeninos enfermos, cuerpos que importan: 'Las primas' de Aurora Venturini

Patsias Valle, Lucia 22 December 2020 (has links)
En la presente tesis, se realiza un análisis exhaustivo de la novela Las primas (2007) de la escritora argentina Aurora Venturini. Sustento que la novela propone modelos de género alternativos a la matriz heterosexual hegemónica como válidas en sí mismas y que van contra la noción de lo normado, generando posibilidades para la existencia de los sujetos. Teniendo en cuenta la biografía y trayectoria de Venturini, Las primas configura un relato innovador y único, además de relevante en cuanto a sus propuestas de reivindicación del cuerpo femenino y los cuerpos considerados ‘disidentes’, en una sociedad que los construye como abyectos y grotescos. La narración plantea a la protagonista como una wounded storyteller (Frank 1995) dentro del marco narrativo del Künstlerroman. Como herramientas teóricas, empleo la teoría de Mikhail Bakhtin sobre lo grotesco y lo abyecto de Julia Kristeva, así como lo propuesto por Judith Butler en El género en disputa (2015 [1990]) y Cuerpos que importan (2002 [1993]) en relación a la performatividad y la matriz heterosexual. Analizo la construcción de los cuerpos, la sexualidad y la maternidad en la novela y la manera en la que la protagonista los considera peligrosos. Asimismo, demuestro cómo el mandato patriarcal actúa de manera velada en la vida de los personajes e impide la sororidad entre las mujeres de la novela, aunque finalmente el patriarcado es subvertido por la protagonista
110

A statistical study of incoherent scatter plasma line enhancements during the International Polar Year ’07-’08 in Svalbard

Hammarsten, Michael January 2016 (has links)
There was a large radar campaign during 2007 and 2008, the International Polar Year (IPY),and at that time the EISCAT Svalbard Radar was operated and measured the ionosphere continuouslyat most times. This report presents statistical results from an electron enhancementpoint of view. Until now there has been some research into the field and results based on theions in the ionosphere, and the enhancements we refer to as Naturally enhanced ion acousticlines (NEIALs). Plasma line data from May 2007 to February 2008 has been analysed inorder to find and classify enhancements as NEIALs have been classified but with respect tothe electron distribution instead of the ion distribution. A method of detection was developedin order to differentiate the enhancements from the background with a relation between theminimum and maximum power of each measured dump. Results show that there is a largedifference between the downshifted plasma lines and the upshifted plasma lines, both has arange distribution peak at 180 km and the upshifted plasma line has another peak at 230 kmwhich the downshifted plasma line does not. The occurrence rate of the enhancements was1.64 % for the downshifted plasma line and 4.69 % for the upshifted plasma line. Threedifferent types of enhancements are classified using the variance distribution for the peakfrequency of that detected dump, Single, Profile, and Diffuse. The Single enhancements havea bit different spectral, range, and time of day distributions than of the Profile and Diffusedistributions. The Diffuse classifications are mostly wrong classifications and aliasing and itis very similar to Profile enhancements as seen by its distribution.

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