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TT-FLASH: Explosion i Oslo : En undersökning om SVT:s, TV4:s och SR:s bevakning av terrordåden i Norge 2011Berg, Alexander, von Schoenberg, Nichol January 2011 (has links)
Den 22 juli 2011 utförde Anders Behring Breivik det värsta terrorattentatet i Norge i modern tid. Svenska medier valde att lägga alla sina resurser på att bevaka katastrofen i grannlandet. I denna uppsats undersöker vi hur SVT, SR och TV4 arbetade med bevakningen. Studien som behandlar nyhetsbevakningens första dygn, går in på vilka etiska, praktiska och källkritiska problem som respektive kanals nyhetsredaktioner ställdes inför (inklusive webben). Vi tar även upp hur arbetet och bemanningen organiserades. Det empiriska materialet bygger på forskningsintervjuer med nyhetschefer, reportrar och webbredaktörer. Studien bygger på Lee B. Beckers och Tudor Vlads översikt om organisering och rutiner på nyhetsorganisationer. Fungerande nyhetsrutiner är ett krav i dagens medielandskap. Nyhetsrutiner används av journalister för att kunna producera nyheter under tidspressade förhållanden. Att dåden skedde en fredagseftermiddag under semestertider försvårade arbetet för redaktionerna. Framför allt SVT och TV4 var underbemannade. Vårt resultat visar också att nyhetsredaktionerna slet med tekniska problem. Framför allt handlar det om reportrar på plats i Norge som hade svårt att få hem sitt material till Sverige. I de fall obekräftade uppgifter publicerades uppgavs alltid uppgiftens källa. Etiska problem som redaktörer och reportrar fick ta ställning till handlade främst om bildmaterial som ansågs för obehagliga eller innehöll bilder på offer som var identifierbara. Även intervjuer med chockade anhöriga diskuterades. Samtliga beslut togs från fall till fall. Studien visar att de undersökta medierna var flexibla i sitt arbete. Den visar också hur beroende webbdeskarna är av tv- och radioredaktionernas arbete. Erfarenhet och flexibilitet hos journalister, nyhetschefer och övrig redaktionell personal gjorde att samtliga redaktioner trots tekniska problem och personalbrist klarade av nyhetsbevakningen. Det visar att redaktionernas nyhetsrutiner i grunden fungerade väl.
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Micromachined epitaxial colossal mognetoresistors for uncooled infrared bolometerKim, Joo-Hyung January 2005 (has links)
<p>High quality perovskite manganites, La1<sub>-x</sub>A<sub>x</sub>MnO<sub>3</sub> (A = Ca, Sr, Ba) are very attractive materials due to their great application potential for magnetic memory, uncooled infrared (IR) microbolometer and spintronics devices. This thesis presents studies of the growth and material characterization (including structural, electrical, magnetic and noise) of epitaxial manganite films on Si and GaAs. Furthermore, investigations about strain effect on structural and electrical properties of manganites, and finally fabrication of self-supported free standing microstructures for uncooled IR bolometer are also demonstrated.</p><p>To obtain high quality epitaxial manganite films on semiconductor substrates at room temperature, using a combination of La<sub>0.67</sub>Sr<sub>0</sub>.<sub>33</sub>MnO<sub>3 </sub>(LSMO) and La<sub>0.67</sub>Ca<sub>0.33</sub>MnO<sub>3 </sub>(LCMO) compounds, La<sub>0.67</sub>(Sr,Ca)<sub>0.33</sub>MnO<sub>3</sub> (LSCMO) films were successfully grown on Si substrates with Bi<sub>4</sub>Ti<sub>3</sub>O<sub>12</sub>(BTO)/CeO<sub>2</sub>/YSZ buffers by pulsed laser deposition (PLD) technique. Crystallographic relations between layers shows cube-on-cube for BTO/CeO2/YSZ/Si and diagonal-on-side for LSCMO films on BTO layer. 4.4 %K<sup>-1 </sup>maximum temperature coefficient of resistivity (TCR = 1/ρ·dρ/dT) and 2.9 %kOe<sup>-1</sup> colossal magnetoresistance (CMR) were obtained at room temperature. Assuming of a prototype of temperature sensor, 1.2 μK/√Hz of noise equivalent temperature difference (NETD) and 2.9×10<sup>8</sup> cm√Hz/W of detectivity are expected to achieve at 294 K, 30 Hz. For GaAs substrates, using MgO buffer layer, LCMO films shows 9.0 %K<sup>-1</sup> of TCR at 223 K while LSMO exhibits 2 %K<sup>-1</sup> at 327 K.</p><p>Systematic strain effects on structural and electrical properties of La<sub>0</sub>.<sub>75</sub>Sr<sub>0.25</sub>MnO<sub>3</sub> LSMO) films on BTO/CeO2/YSZ-buffered Si, Si<sub>1-x</sub>Ge<sub>x</sub>/Si (compressive strain, x = 0.05-0.20) and Si<sub>1-y</sub>C<sub>y</sub>/Si (tensile, y = 0.01) were investigated. The strain induced from Si<sub>1-x</sub>Ge<sub>x</sub>/Si and Si<sub>0.99</sub>C<sub>0.01</sub>/Si has a tendency to decrease the roughness of CMR films compared to Si sample. High resistivity and low TCR values are observed for Si<sub>0.8</sub>Ge<sub>0</sub>.<sub>2</sub>/Si and Si<sub>0.99</sub>C<sub>0.01</sub>/Si samples due to excessive strains whereas Si<sub>0</sub>.<sub>9</sub>Ge<sub>0.1</sub>/Si and Si<sub>0.95</sub>Ge<sub>0.05</sub>/Si show slight improvements of films quality and TCR value.</p><p>To fabricate LSCMO manganite bolometer on Si, wet etching with KOH and BHF and dry etching methods with Ar ion beam etching (IBE) were studied. For KOH wet etching, LSCMO films show high chemical resistance with lower than 0.2 nm/min of etch rate. BHF wet etching shows high etching selectivity over photoresist mask and silicon substrates. The etch rates for LSCMO and BTO layers are 22 and 17 nm/min. For Ar IBE, LSCMO films and oxide buffer layers show similar etch rates, 16-17 nm/min that are lower compared to 24 nm/min for Si.</p><p>Free standing, self-supported heteroepitaxial LSCMO/BTO/CeO<sub>2</sub>/YSZ membranes for bolometer pixels on Si was successfully fabricated by Ar IBE and ICP etching techniques using a preannealed photoresist. The structural investigation by TEM revealed the sharp interfaces between layers. The electrical property of the free standing membrane was slightly degraded due to strain release and multi-step etching effect. These results demonstrate feasibility to use heteroepitaxial oxide structures as a thermally isolated membrane with conventional photoresist patterning.</p>
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Serine/Arginine-rich proteins in Physcomitrella patensRing, Andreas January 2011 (has links)
Serine/Arginine-rich proteins (SR-proteins) have been well characterized in metazoans and in the flowering plant Arabidopsis thaliana. But so far no attempts on characterizing SR-proteins in the moss Physcomitrella patens have been done. SR-proteins are a conserved family of splicing regulators essential for constitutive- and alternative splicing. SR-proteins are mediators of alternative splicing (AS) and may be alternatively spliced themselves as a form of gene regulation. Three novel SR-proteins of the SR-subfamily were identified in P. patens. The three genes show conserved intron-exon structure and protein domain distribution, not surprising since the gene family has evidently evolved through gene duplications. The SR-proteins PpSR40 and PpSR36 show differential tissue-specific expression, whereas PpSR39 does not. Tissue-specific expression of SR-proteins has also been seen in A. thaliana. SR-proteins determine splice-site usage in a concentration dependent manner. SR-protein overexpression experiments in A. thaliana and Oryza sativa have shown alteration of splicing patterns of endogenous SR-proteins. Overexpression of PpSR40 did not alter the splicing patterns of PpSR40, PpSR36 and PpSR39. This suggests that they might not be a substrate for PpSR40. These first results of SR-protein characterization in P. patens may provide insights on the SR-protein regulation mechanisms of the common land plant ancestor.
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Origin of rutile-bearing ilmenite Fe-Ti deposits in Proterozoic anorthosite massifs of the Grenville ProvinceMorisset, Caroline-Emmanuelle 11 1900 (has links)
The Saint-Urbain and Big Island rutile-bearing ilmenite Fe-Ti oxide deposits are located
in the composite 450 km² Saint-Urbain anorthosite (1055-1046 Ma, U-Pb zircon) and in
the Lac Allard intrusion (1057-1062 Ma, U-Pb zircon) of the 11,000 km² Havre-Saint
Pierre anorthosite suite, respectively, in the Grenville Province of Eastern Canada. Slow
cooling rates of 3-4°C/m.y. are estimated for both anorthosites, based on combined U-Pb
zircon/rutile/apatite and ⁴⁰Ar/³⁹ Ar biotite/plagioclase geochronology, and resulted from
emplacement during the active Ottawan Orogeny. Slow cooling facilitated (1) diffusion
of Zr from ilmenite and rutile, producing thin (10-100 microns) zircon rims on these
minerals, and (2) formation of sapphirine via sub-so lidus reactions of the type: spinel +
orthopyroxene + rutile ± corundum → sapphirine + ilmenite. New chemical and
analytical methods were developed to determine the trace element concentrations and Hf
isotopic compositions of Ti-based oxides. Rutile is a magmatic phase in the deposits
with minimum crystallization temperatures of 781°C to 1016°C, calculated by Zr-in
rutile thermometry. Ilmenite present in rutile-free samples has higher Xhem (hematite
proportion in ilmenite), higher high field strength element concentrations (Xhem = 30-17;
Nb = 16.1-30.5 ppm; Ta 1.28-1.70 ppm), and crystallized at higher temperatures than
ilmenite with more fractionated compositions (Xhem = 21-11; Nb = 1.36-3.11 ppm; Ta =
<0.18 ppm) from rutile-bearing rocks. The oxide deposits formed by density segregation
and accumulation at the bottom of magma reservoirs, in conditions closed to oxygen,
from magmas enriched in Fe and Ti. The initial ¹⁷⁶Hf/¹⁷⁷ Hf of rutile and ilmenite (Saint
Urbain [SU] = 0.28219-0.28227, Big Island [BI] = 0.28218-0.28222), and the initial Pb
isotopic ratios (e.g.²⁰⁶Pb/²⁰⁴ Pb: SU = 17.134-17.164, BI = 17.012-17.036) and ⁸⁷Sr/⁸⁶ Sr
(SU = 0.70399-0.70532, BI = 0.70412-0.70427) of plagioclase from the deposits overlap
with the initial isotopic ratios of ilmenite and plagioclase from each host anorthosite,
which indicates that they have common parent magmas and sources. The parent magmas
were derived from a relatively depleted mantle reservoir that appears to be the primary
source of all Grenvillian anorthosite massifs and existed for --600 m.y. along the margin
of Laurentia during the Proterozoic.
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Origin and Geochemistry of Modern Bahamian OoidsDuguid, SARAH 27 January 2009 (has links)
The Bahamian Archipelago is one of the few locations in the world where ooid formation is actively occurring. Ooid cortices from six locations in the region were incrementally dissolved and analyzed for 14C, δ18O, δ13C, Mg/Ca and Sr/Ca ratios. Ooids were examined under SEM after each step in the incremental analyses to characterize the nature of dissolution. Radiocarbon dating indicates that surface ooids began forming across the Archipelago between 1000 and 2800 yr BP and continue to form today.
The ooids have the same pattern of microboring alteration across the region. The surface and outer cortex of the ooids are punctuated with unfilled microborings, whereas the inner cortex contains two morphologies of aragonite cement filling the microborings. The two morphologies of cement form in association with two different species of cyanobacteria, one is Solentia sp. the other is interpreted to be Hyella sp..
The chemistry of ooids from across the region is remarkably similar. δ18O and δ13C values for all samples vary directly, having a slope of approximately 1. The outer cortex has low δ18O and δ13C values of -3.4‰ and 0.2‰ respectively, whereas the δ18O and δ13C values of the inner cortex are high with values of 1.9‰ and 6.8‰ respectively. The presence of aragonite cement in microborings in the inner cortex increases the overall isotopic composition of both oxygen and carbon in the ooid, causing it to appear close to equilibrium with seawater. The isotopic variation in δ18O and δ13C within the cortex can be characterized as a mixing line between the low values in the unaltered ooid laminae and the aragonite cement in the microborings.
The most exterior portion of the ooid has very high Mg/Ca values and is interpreted as an amorphous calcium carbonate (ACC) coating. There are two other phases in the cortex, both being aragonite. The outer cortex has a higher Mg/Ca ratio and lower Sr/Ca ratio than the inner cortex. This difference in chemistry is a result of the presence of aragonite cement in the inner cortex.
Stable isotopic and trace element results coupled with SEM investigations indicate that microbes do not play a role in ooid formation, but instead alter the texture and chemistry of ooids after they have formed. This alteration occurs throughout the entire shoal region. A new model of ooid formation is proposed whereby a veneer of ACC precipitates on an ooid while it is at the sediment-water interface (the active phase). This veneer of ACC later recrystallizes to aragonite needles, possibly nucleating on organic material and a new cortex layer is formed. Observations from this study lead to a deeper understanding of the chemical processes involved in ooid genesis, which allows for a better understanding of paleoenvironments hosting ooid formation. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2009-01-27 13:29:42.765
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A Study on Reliability-based Selective Repeat Automatic Repeat Request for Reduction of Discrimination Time of P300 SpellerFuruhashi, Takeshi, Yoshikawa, Tomohiro, Takahashi, Hiromu, Kaneda, Yusuke January 2010 (has links)
Session ID: SA-B1-2 / SCIS & ISIS 2010, Joint 5th International Conference on Soft Computing and Intelligent Systems and 11th International Symposium on Advanced Intelligent Systems. December 8-12, 2010, Okayama Convention Center, Okayama, Japan
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A comparison on the release modifying behaviour of chitosan and kollidon SR / Carel Petrus BouwerBouwer, Carel Petrus January 2007 (has links)
Controlled release formulations deliver an active ingredient over an extended period of time. It is an ideal dosage form for an active ingredient with a short elimination half-life. An active ingredient with a short elimination half-life would be released in small portions over an extended period of time and thus less frequent administration is necessary and this improve patient compliance. Other advantages of these formulations include: decreased side effects, constant drug levels in the blood, improvement in treatment efficiency and reduction in cost of administration.
Controlled release beads are formulated in such a way that the active ingredient is embedded in a matrix of insoluble substance like chitosan; the dissolving drug then has to find its way through the pores of the matrix into the surrounding medium. The chitosan matrix swells to form a gel, the drug then has to first dissolve in the matrix and diffuse through the outer surface into the surrounding medium.
Chitosan is a biocompatible, biodegradable polymer of natural origin. It has mucoadhesive properties as well as the ability to manipulate the tight junctions in the epithelium membrane and these properties have qualified chitosan as an effective drug carrier in controlled release dosage forms. The effect of a modern controlled release polymer namely Kollidon® SR in combination with chitosan on drug release was investigated. Ketoprofen was chosen as model drug. Ketoprofen is an anti-inflammatory drug that causes gastrointestinal side effects in conventional dosage forms. Ketoprofen has a short elimination half-life of 2.05 ± 0.58 h and this characteristic makes it an ideal candidate for use in a controlled release formulation. The aim of this study was to achieve controlled release and minimize gastrointestinal effects of ketoprofen with chitosan particles. Kollidon® SR was used as polymer because it exhibits pH independent release characteristics and previous studies have shown potential for this combination.
Chitosan beads and chitosan-Kollidon® SR beads, as well as chitosan granules and chitosan-Kollidon® SR granules, were prepared and investigated as potential controlled release formulations. Chitosan beads were prepared through the inotropic gelation method using tripolyphosphate as a cross linking agent. Granules were prepared through wet granulation using 2% v/v acetic acid as the granulating fluid or by dissolving ketoprofen in ethanol and Kollidon® SR in 2-pyrrolidinone and using the solution as granulating fluid. Kollidon® SR was added in concentrations of 0.25, 0.5 and 1% (w/v) in the bead formulations and concentrations of 1, 5 and 10% (w/w) in the granule formulations. The beads and granules were characterised by evaluating the following properties: morphology, drug loading and drug release. Additionally swelling and friability tests were also conducted on the bead formulations.
The cross linking times of the bead formulations were varied to investigate the effect of cross linking time on the characteristics of the beads. Chitosan-Kollidon® SR beads showed promising results for controlled release formulations and ketoprofen were released over an extended period of time. Drug loading of the plain chitosan beads was 74.65 ± 0.71% and it was noted that the inclusion of Kollidon® SR in the beads resulted in an increase in drug loading and the formulation containing 1% (w/v) Kollidon® SR, cross linked for 30 minutes had a drug loading of 77.38 ± 0.01%. Drug loading of the beads that were cross linked for a longer time were slightly lower which is an indication that some of the drug might have leached out during cross linking. The degree of swelling was promising with some beads swelling to a degree of 2.5 in phosphate buffer solution pH 5.6. Granules had a drug loading between 81.73 ± 1.53% and 93.30 ± 0.50%.
Ketoprofen release from the beads and the granules in PBS pH 7.40 at 37 °C over a period of 6 hours were investigated. The bead formulations were more effective in achieving controlled release and it was noted that the bead formulations that was cross linked for a longer period was more efficient in achieving controlled release. The granules did not form a matrix and were not effective in achieving controlled release. Controlled release of ketoprofen were achieved and the results show potential for chitosan-Kollidon® SR formulations in the future. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2008.
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Aplicação de métodos radiométricos (Rb-Sr e Sm-Nd) na análise de bacias sedimentares o exemplo da Bacia do ParanáSilva, Diogo Rodrigues Andrade da January 2006 (has links)
Os métodos radiométricos (Rb-Sr e Sm-Nd) têm sido aplicados, com sucesso, em rochas sedimentares visando a obtenção de idades deposicionais e informações sobre proveniência. Em muitos casos, apesar dos resultados geologicamente significativos, ainda persistem dúvidas em relação a extensão e interpretação dos dados obtidos. Isto ocorre porque as rochas sedimentares resultam da mistura de fragmentos detríticos de diversas proveniências com diferentes sistemas isotópicos, conseqüentemente, já contendo um registro isotópico da rocha fonte. No caso do método Rb-Sr, aplicado em rochas sedimentares de granulometria fina, pode-se obter idades absolutas para o evento deposicional. Isto é viável desde que este registro isotópico proveniente das rochas fonte seja apagado no momento da deposição, ou seja, deve ocorrer a homogeneização isotópica do Sr no ambiente sedimentar. Para tanto, devem ser observados alguns pré-requisitos em relação a amostragem, granulometria, ambiente deposicional e composição mineralógica das amostras, entre outros. No entanto, ainda existem questionamentos em relação a esta metodologia especialmente quanto à ocorrência e à extensão do processo de homogeneização isotópica do Sr em ambiente sedimentar.(Continua0 O método Sm-Nd, apesar de ser uma técnica relativamente nova quando aplicada a rochas sedimentares, tem se tornado uma ferramenta fundamental para auxílio na determinação de proveniência de rochas sedimentares. As maiores dificuldades estão na correta interpretação dos valores obtidos e sua associação com um ambiente sedimentar, ou seja, de baixa temperatura. Neste trabalho, foram aplicados os métodos radiométricos Rb-Sr e Sm-Nd em amostras de rochas sedimentares coletadas em diferentes contextos geológicos da Bacia do Paraná. Foram tentativamente testados os diferentes parâmetros que atuam no sentido da homogeneização isotópica do Sr e do comportamento do Nd. Os resultados obtidos permitiram aprimorar a metodologia radiométrica Rb-Sr e Sm-Nd quando aplicada em rochas sedimentares, bem como obter resultados sobre a idade deposicional de diferentes unidades sedimentares e, por vezes, sua proveniência.
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Aplicação de métodos radiométricos (Rb-Sr e Sm-Nd) na análise de bacias sedimentares o exemplo da Bacia do ParanáSilva, Diogo Rodrigues Andrade da January 2006 (has links)
Os métodos radiométricos (Rb-Sr e Sm-Nd) têm sido aplicados, com sucesso, em rochas sedimentares visando a obtenção de idades deposicionais e informações sobre proveniência. Em muitos casos, apesar dos resultados geologicamente significativos, ainda persistem dúvidas em relação a extensão e interpretação dos dados obtidos. Isto ocorre porque as rochas sedimentares resultam da mistura de fragmentos detríticos de diversas proveniências com diferentes sistemas isotópicos, conseqüentemente, já contendo um registro isotópico da rocha fonte. No caso do método Rb-Sr, aplicado em rochas sedimentares de granulometria fina, pode-se obter idades absolutas para o evento deposicional. Isto é viável desde que este registro isotópico proveniente das rochas fonte seja apagado no momento da deposição, ou seja, deve ocorrer a homogeneização isotópica do Sr no ambiente sedimentar. Para tanto, devem ser observados alguns pré-requisitos em relação a amostragem, granulometria, ambiente deposicional e composição mineralógica das amostras, entre outros. No entanto, ainda existem questionamentos em relação a esta metodologia especialmente quanto à ocorrência e à extensão do processo de homogeneização isotópica do Sr em ambiente sedimentar.(Continua0 O método Sm-Nd, apesar de ser uma técnica relativamente nova quando aplicada a rochas sedimentares, tem se tornado uma ferramenta fundamental para auxílio na determinação de proveniência de rochas sedimentares. As maiores dificuldades estão na correta interpretação dos valores obtidos e sua associação com um ambiente sedimentar, ou seja, de baixa temperatura. Neste trabalho, foram aplicados os métodos radiométricos Rb-Sr e Sm-Nd em amostras de rochas sedimentares coletadas em diferentes contextos geológicos da Bacia do Paraná. Foram tentativamente testados os diferentes parâmetros que atuam no sentido da homogeneização isotópica do Sr e do comportamento do Nd. Os resultados obtidos permitiram aprimorar a metodologia radiométrica Rb-Sr e Sm-Nd quando aplicada em rochas sedimentares, bem como obter resultados sobre a idade deposicional de diferentes unidades sedimentares e, por vezes, sua proveniência.
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Aplicação de métodos radiométricos (Rb-Sr e Sm-Nd) na análise de bacias sedimentares o exemplo da Bacia do ParanáSilva, Diogo Rodrigues Andrade da January 2006 (has links)
Os métodos radiométricos (Rb-Sr e Sm-Nd) têm sido aplicados, com sucesso, em rochas sedimentares visando a obtenção de idades deposicionais e informações sobre proveniência. Em muitos casos, apesar dos resultados geologicamente significativos, ainda persistem dúvidas em relação a extensão e interpretação dos dados obtidos. Isto ocorre porque as rochas sedimentares resultam da mistura de fragmentos detríticos de diversas proveniências com diferentes sistemas isotópicos, conseqüentemente, já contendo um registro isotópico da rocha fonte. No caso do método Rb-Sr, aplicado em rochas sedimentares de granulometria fina, pode-se obter idades absolutas para o evento deposicional. Isto é viável desde que este registro isotópico proveniente das rochas fonte seja apagado no momento da deposição, ou seja, deve ocorrer a homogeneização isotópica do Sr no ambiente sedimentar. Para tanto, devem ser observados alguns pré-requisitos em relação a amostragem, granulometria, ambiente deposicional e composição mineralógica das amostras, entre outros. No entanto, ainda existem questionamentos em relação a esta metodologia especialmente quanto à ocorrência e à extensão do processo de homogeneização isotópica do Sr em ambiente sedimentar.(Continua0 O método Sm-Nd, apesar de ser uma técnica relativamente nova quando aplicada a rochas sedimentares, tem se tornado uma ferramenta fundamental para auxílio na determinação de proveniência de rochas sedimentares. As maiores dificuldades estão na correta interpretação dos valores obtidos e sua associação com um ambiente sedimentar, ou seja, de baixa temperatura. Neste trabalho, foram aplicados os métodos radiométricos Rb-Sr e Sm-Nd em amostras de rochas sedimentares coletadas em diferentes contextos geológicos da Bacia do Paraná. Foram tentativamente testados os diferentes parâmetros que atuam no sentido da homogeneização isotópica do Sr e do comportamento do Nd. Os resultados obtidos permitiram aprimorar a metodologia radiométrica Rb-Sr e Sm-Nd quando aplicada em rochas sedimentares, bem como obter resultados sobre a idade deposicional de diferentes unidades sedimentares e, por vezes, sua proveniência.
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