Made available in DSpace on 2014-06-12T23:14:37Z (GMT). No. of bitstreams: 2 arquivo8665_1.pdf: 2737608 bytes, checksum: 964c4063f82e235ed012a56e02f126ef (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O objetivo deste estudo foi avaliar a degradação por fratura sob tensão ambiental (environmental stress cracking ou ESC) de alguns polímeros vítreos, o poli(metacrilato de metila), o poliestireno e o poli (metacrilato de metila) tenacificado (PMMA-t), após esses polímeros terem sido submetidos a diferentes doses de radiação gama. A exposição à radiação gama foi realizada com doses de até 200kGy utilizando uma fonte de cobalto-60. Foram feitas avaliações prévias sobre o efeito da radiação gama na estrutura do polímero por meio de ensaios de massa molar, espectroscopia no infravermelho e visível, e ensaios de absorção de líquido, em que foram comparados os resultados obtidos para os polímeros irradiados nas diferentes doses com os do não-irradiado. Os estudos de ESC consistiram em submeter os polímeros a ensaios de tração em diferentes taxas de deformação e relaxação de tensão sob líquido e sem líquido. Análises de microscopia ótica e eletrônica de varredura foram feitas na superfície de fratura após ensaios de ESC. A radiação gama promoveu intensas mudanças na massa molar do PMMA e PMMA-t e ocasionou apenas modificações moderadas no PS. As velocidades de absorção de etanol pelo PMMA e PMMA-t aumentaram com o aumento da dose. Para o PS a velocidade de absorção de querosene reduziu nas duas doses maiores (100 e 200kGy). O PMMA e o PMMA-t mostraram nítida dependência do efeito de ESC com a dose de radiação gama e com as condições de ensaio, evidenciada pela maior redução percentual da tensão de ruptura e deformação na ruptura verificada em ensaios realizados com líquidos em comparação aos sem líquido. O poliestireno mostrou a menor dependência do efeito de ESC com a dose de radiação gama

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A comprehensive evaluation of roll and yaw stability of tractor/semitrailers with single and dual trailers in city and highway conditions is conducted. Commercial vehicles fundamentally behave differently in city driving conditions than at high speeds during highway driving conditions. In order to closely examine each, this study offers two distinct evaluations of commercial vehicles: 1) low-speed driving in tight turns, representative of city driving; and 2) high-speed lane change and evasive maneuvers, typical of highway driving. Specifically, for city driving, the geometric parameters of the roadway in places where tight turns occur—such as in roundabouts—are closely examined in a simulation study in order to evaluate the elements that could cause large vehicle body lean (or high rollover index), besides the truck elements that have most often been studied. Two roundabout geometries, 140-ft single-lane and a 180-ft double-lane, are examined for various truck load conditions and configurations. The vehicle configurations that are considered are a straight 4x2 truck, a tractor with a 53-ft semi-trailer (commonly known as WB-67), and two trucks in double-trailer configurations. Five potential factors are identified and thoroughly studied: circulatory roadway cross-section, roundabout tilt, truck configurations, truck apron geometry, and truck load condition. The results of the study indicate that when the rear axles of the trailer encounter the truck apron in the roundabout, the climbing and disembarking action can cause wheel unloading on the opposite side, therefore significantly increasing the risk of rollover. Interestingly, in contrast to most high-speed rollovers that happen with fully-loaded trailers, at low speeds, the highest risks are associated with lightly loaded or unloaded trucks. For high-speed driving conditions, typical of highway driving, a semi-truck with a double 28-ft trailer configuration is considered, mainly due to its increasing use on U.S. roads. The effect of active safety systems for commercial vehicles, namely Roll Stability Control (RSC) for trailers and Electronic Stability Control (ESC) for the tractor, is closely examined in a test study. Various trailer loading possibilities are evaluated for different combinations of ESC/RSC on the tractor and trailer, respectively. The results of the study indicate that 1) RSC systems reduce the risk of high-speed rollovers in both front and rear trailers, 2) the combination of ESC (on tractor) and RSC (on trailer) reduce the risk of rollover and jackknifing, and 3) RSC systems perform less effectively when the rear trailer is empty. / PHD

Syftet med denna studie är att analysera de fyra senaste nordiska vinnarbidragen i Eurovision Song Contest, för att se om det föreligger återkommande mönster, normativa könsstereotyper och hur makt uttrycks i tävlingen. Genom multimodala analyser av dessa bidrag med fokus på kön och makt, kommer följande frågeställningar att besvaras: Hur ser den multimodala gestaltningen ut inom de fyra senaste nordiska vinnarbidragen i Eurovision Song Contest? Samt: Hur representeras kvinnor respektive män i de olika bidragen? Som material för analyserna har Youtube-klipp på samtliga bidrag använts, där det multimediala har analyserats genom multimodala analyser. Efter dessa analyser blir sammanfattningen att det finns återkommande mönster och könsstereotyper inom ESC, där männen ofta tilldelas makt medan kvinnor i stället är den mer försumbara. Dessa mönster och stereotyper ser vi inte givetvis vid första inblicken av ett bidrag, utan genom att göra djupare multimodala analyser. / The primary aim of this study is to examine and analyze how different media (multimedia or mixed media) in the Eurovision Song Contest work togheter when combined. The expectation is to see if there are reocurring themes and patterns in the representation of the Nordic countries in the ESC with a main focus on gender bias and authority. Four different winning entries from the Eurovision Song Contest performed by the Nordic countries have been chosen and analyzed. The thesis in this essay is that there are patterns in the representation of different countries in the ESC, and that there also may occur stereotypical gender bias. Therefore the key questions have been the following: What does the multimodal impersonation of the latest four Nordic winners in the ESC look like? And: What does the representation of men and women look like? Youtube-videos have been used as material to analyse these performances by doing multimodal analyses. This study indicates that there are occuring gender bias and stereotypes in the ESC, and also reoccuring patterns in the representation of the Nordic countries as a geographical area. We can not see this by the first glimpse, but through deeper multiodal analyses.

In 1944, the Soviet Union deported hundreds of thousands of Crimean Tatars from Crimea, one of whom was the Ukrainian artist Jamala's great-grandmother Nazylchan. Almost a hundred years later, and only two years after Russia's annexation of Crimea, Jamala represents Ukraine in the Eurovision Song Contest 2016 with the song "1944". The song is about the great-grandmother's experiences of the deportation of Crimean Tatars and was accused of containing political messages, which becomes relevant as the competition prohibits all kinds of political elements. The contribution was reviewed by the EBU, the European Broadcasting Union, and was not judged to be political. The Eurovision Song Contest is an avowedly non-political competition that was started after the Second World War with the aim of keeping the peace in Europe and giving Europeans something to unite around. The countries participating in the competition nominate artists and songs that represent the country in the international music competition. This study examines how the case of Jamala and the contribution "1944" has been used in and outside the competition by Jamala to create awareness and mobilize support for both Ukraine and Crimean Tatars with the deportation of Crimean Tatars in 1944, the annexation of Crimea in 2014 and the invasion of Ukraine in 2022. To examine how Jamala identifies with her family, how she relates to what is political and what is not, as well as how she and other representatives of countries in international cultural events can be understood as political ambassadors, this study can provide some answers to how politics, national identity and representation in that type of context can be understood to be related. / År 1944 deporterade Sovjetunionen hundratusentals krimtatarer från Krim, en av dem var artisten Jamalas gammelfarmor Nazylchan. Nästan hundra år senare och bara två år efter Rysslands annektering av Krim ställer Jamala upp som representant för Ukraina i Eurovision Song Contest 2016 med låten "1944". Låten handlar om gammelfarmoderns upplevelser av deportationen av krimtatarer och anklagas för att innehålla politiska budskap, vilket blir relevant då tävlingen förbjuder alla typer av politiska inslag. Bidraget granskas av EBU, the European Broadcasting Union, och bedöms inte vara politisk. Eurovision Song Contest är en uttalat icke-politisk tävling som startades efter andra världskriget med syfte att behålla freden i Europa och ge européerna något att enas kring. Länderna som medverkar i tävlingen utser artister och låtar som representerar landet i den internationella musiktävlingen. Denna studie undersöker hur fallet Jamala och bidraget "1944" använts i och utanför tävlingen av Jamala för att skapa medvetenhet kring och mobilisera stöd till såväl Ukraina som krimtatarer i och med deportationen av krimtatarer 1944, annekteringen av Krim 2014 samt invasionen av Ukraina 2022. Genom att undersöka hur Jamala identifierar sig med sin familj, hur hon förhåller sig till vad som är politiskt och inte samt hur hon och andra representanter för länder i internationella kulturella evenemang kan förstås som politiska ambassadörer kan denna studie ge några svar på hur politik, nationell identitet och representation i den typen av sammanhang kan förstås höra samman.

Tyrimo objektas ir metodai: dobilų genties augalų lapų, stiebų, žiedų žaliavų tyrimas. Izoflavonai nustatyti ESC metodu. Darbo tikslas: Atlikti izoflavonų genisteino, formononetino ir daidzeino analizę dobilų genties augaluose, taikant ESC metodą. Darbo uždaviniai: atlikti literatūros analizę, apibendrinant dobilų (Trifolium L) genties augalų biologines savybes, izoflavonų taikymą gydymo tikslais ir nustatymo metodus. Parinkti ekstrakcijos sąlygas, įvertinant pasirinkto ekstrakcijos tirpiklio, jo poliškumo ir ekstrakcijos laiko įtaką. Optimizuoti ESC metodą dobilų žaliavos tyrimui ir pagrįsti metodo tinkamumą izoflavonų kiekio nustatymui. Atlikti įvairių dobilų rūšių lapų, žiedų, stiebų ir šaknų mėginių analizę optimizuotu ESC metodu ir nustatyti izoflavonų kiekius juose. Įvertinti izoflavonų kiekio įvairavimą skirtingose dobilų rūšyse. Nustatyti izoflavonų kiekybinės sudėties pasiskirstymą augalų dalyse. Palyginti T. pratense izoflavonų kiekių skirtumus augalo dalyse. Palyginti izoflavonų kiekybinės sudėties skirtumus T. pratense kultivuojamų ir laukinės populiacijos augalų žaliavose. Išvados: atlikus mokslinės literatūros šaltinių analizę, apibendrintos dobilų genties augalų biologinės savybės, izoflavonų taikymas gydymo tikslais ir flavonoidų bei izoflavonoidų nustatymo metodai. Įvertintas tirpiklio poliškumas ir taikomos ekstrakcijos trukmės įtaka izoflavonų kiekiui. Optimizuotas ESC metodas kiekybinei izoflavonų analizei dobilų (Trifolium L.) genties augalų žaliavoms... [toliau žr. visą tekstą] / Object and methods: phytochemical analysis of different parts (leaves, blossoms, roots) of clover genus plants. Aim: to perform analysis of isoflavons genistein, formononetin and daidzein in clover genus plants by HPLC method. Objective: to perform analysis of scientific literature and evaluate characteristics of clover genus (Trifolium L.) plants and their usage for medical purpose, and analysis methods of active components. Select the conditions of extraction considering influence of solvent, its polarity and time of extraction. Optimize HPLC method for raw material analysis of clover genus and justify its suitability for quantitative analysis of isoflavons. Perform analysis of isoflavons in different parts of various clover genus plants by optimized HPLC method. Evaluate quantity difference between isoflavons in various genus of clover. Evaluate quantity difference between isoflavons in different parts of plants. Compare quantities of isoflavons in different parts of T. pratense pants. Compare quantity difference between isoflavons in raw materials of cultivated and naturally grown T. pretense plants. Results: performed scientific literature analysis justified characteristics and therapeutic effects of clover genus (Trifolium L.) plants, evaluated analysis methods of flavonoids and isoflavonoids. Also was evaluated influence of polarity of solvent and time of extraction to quantity of isoflavons. Quantitative HPLC analysis method for isoflavons in raw materials of clover... [to full text]

Fibroblast growth factor (FGF) signalling plays many fundamentally important roles during the development of the mammalian embryo. However, its effects on pluripotent stem cells derived from mouse and human embryos appear to be markedly different. FGF2 is routinely added to culture medium for propagating undifferentiated human (hES) cells, whereas in mouse (mES) cell cultures FGFs have been described as regulators of their differentiated progeny. To assess the effect of FGF signalling on undifferentiated mES cells, the effects of FGF2 and 4 were analysed in the presence of saturating and sub-saturating levels of the inhibitor of differentiation, leukaemia inhibitory factor (LIF). Mouse ES cell self-renewal was quantified by measuring the expression of the stem cell specific reporter Oct4-LacZ in biochemical and fluorometric assays. Treatment with FGF reduced the expression of the OCT4-LacZ reporter, even under saturating concentrations of LIF and this was mirrored by decreased levels of OCT4 protein. Furthermore, treatment with FGF leads to upregulation of the ectodermal differentiation marker Pax6. These results suggest that FGF signalling has a direct impact on undifferentiated mES cells, and actively promotes their differentiation. To asses the effect of FGF signalling on hES cells without the influence of undefined factors, a feeder and serum free system was developed. Cells growing in this conditions for >20 passages maintained expression of surface (SSEA3 and TRA1-60 and 81) and internal (OCT4) markers specific for undifferentiated hES cells. Expression of these markers was dependant on the continuous presence of FGF2. Indeed, withdrawal of FGF2 resulted in a rapid decrease of in hES cell growth and of the emergence of cell flattened morphology and of the surface marker SSEA1, changes typically associated with differentiation. Two important signals activated by FGF in hES cells are the ERK/MAPK and PI3K pathways. To assess their functional relevance, hES cell cultures were treated with the drugs UO126 and LY294002, inhibitors of the MAPK and PI3K pathways respectively. Drug mediated suppression of the phosphorylation of these pathways, correlated with a reduction in cell growth, flattening of the colonies and reduction in SSEA4 expression. Use of SB431542, specific inhibitor of TGFβ/activin type I receptor kinase (Alk5) also resulted in the flattening of the colonies and the appearance of dispersed cells. Therefore, inhibition of MAPK and PI3K appears to impair growth and self-renewal in hES cells and this may be happening in conjunction with TGFβ/Activin pathway. Taken together, these results suggest that FGF signalling has opposite effects in mouse and human ES cells: inducing differentiation in mES and sustaining self-renewal in hES.

Master of Science / Department of Computing and Information Science / Torben Amtoft / Invariants are properties which are asserted to be true at certain program points. Invariants are of paramount importance when proving program correctness and program properties. Method, constructor, and class invariants can serve as contracts which specify program behavior and can lead to more accurate reuse of code; more accurate than comments because contracts are less error prone and they may be proved without testing. Dynamic invariant generation techniques run the program under inspection and observe the values that are computed at each program point and report a list of invariants that were observed to be possibly true. Static checkers observe program code and try to prove the correctness of annotated invariants by generating proofs for them. This project attempts to get strong invariants for a subset of classes in Java; there are two phases first we use Daikon, a tool that suggests invariants using dynamic invariant generation techniques, and next we get the invariants checked using ESC/Java2, which is a static checker for Java. In the first phase an ‘Instrumenter’ program inspects Java classes and generates code such that sufficient information is supplied to Daikon to generate strong invariants. All of this is achieved without any user input. The aim is to be able to understand the behavior of a program using already existing tools.

<p>The objective of this thesis is to implement a basic, yet realistic, ESC system into the VTI simulator environment. This system is then validated to assure that it is working properly and provides a realistic behavior.</p><p>The implemented ESC system is used in a study, where the ESC system could be turned on and off, to evaluate the benefits of an ESC system after a side impact. This study shows that an ESC system may aid the driver in such a critical situation when the driver is unaware that a side impact will occur. With the ESC system active no driver lost control while with the system inactive there were five drivers that lost control, but deviations in initial speed give statistical difficulties, thus more tests are needed. In the case where the driver knows that an impact will occur the ESC system showed to stabilize the automobile faster and it is shown that an expected improvement in stabilization time is between 40 to 62 percent. It was also seen during this part of the scenario that 2 percent loss of control occurred with an active ESC system and 45 percent without.</p>