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Dissertations / Theses on the topic 'Iod'

Author: Grafiati
Published: 4 June 2021
Last updated: 20 February 2023

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1

Ernst, Thomas. "Anthropogenes Iod-129 als Tracer für Umweltprozesse ein Beitrag zum Verhalten von Spurenstoffen bei der Migration in Böden und beim atmosphärischen Transport /." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970679068.

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2

Szidat, Sönke. "Iod-129 Probenvorbereitung, Qualitätssicherung und Analyse von Umweltmaterialien /." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=960643281.

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3

Daraoui, Abdelouahed [Verfasser]. "Migration von Iod-129 und retrospektive Dosimetrie / Abdelouahed Daraoui." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover, 2010. http://d-nb.info/1005408637/34.

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4

Langenauer, Marcel. "Vergleich der Gehalte an Fluor, Chlor, Brom und Iod in antarktischen und nicht-antarktischen Meteoriten : Bestimmung von Fluor und Iod in organischen Materialien /." [S.l.] : [s.n.], 1993. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.

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5

Schmidt, Annette Christine. "129I und stabiles Iod in Umweltproben Qualitätskontrolle von Analysenmethoden und Untersuchungen zur Radioökologie und zur retrospektiven Dosimetrie /." [S.l. : s.n.], 1998. http://deposit.ddb.de/cgi-bin/dokserv?idn=954459563.

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6

Haubold, Kathrin. "Aspekte der Schilddrüsenphysiologie am Beispiel von Iod, TSHR und IGF-IR." Doctoral thesis, Universitätsbibliothek Leipzig, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-108132.

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Im Rahmen der vorliegenden Arbeit wurden zentrale Aspekte der Schilddrüsenphysiologie am Beispiel von Iod, TSHR und IGF-IR untersucht. Der Pathologie der Schilddrüsenautonomie liegen konstitutiv aktivierende Mutationen des TSHR zugrunde. Die Prävalenz der Schilddrüsenautonomie ist in Iod armen Regionen deutlich erhöht. Als Ursache für Mutationen im TSHR wird vermehrter oxidativer Stress unter Iodmangel angenommen (Krohn et al. 2007; Maier et al. 2007). Die genauen molekularen Mechanismen konnten bisher noch nicht hinreichend aufgeklärt werden. In diesem Zusammenhang interessierte uns inwiefern eine ausreichende Iodversorgung die Entwicklung bereits autonomer Zellen beeinflussen kann. Das verwendete in vitro Modell der Schilddrüsenautonomie mit konstitutiv aktivierenden Mutationen im TSHR wurde bereits in früheren Arbeiten charakterisiert (Führer et al. 2003). Mit Hilfe von Microarray Untersuchungen und Funktionsanalysen, konnten wir deutliche Genregulationen durch Iod an Hand von normalen und autonomen Thyreozyten erkennen. Besonders auffällig war die differentielle Regulation von Genen, die z.B. in der Proliferation, dem Zellzyklus und metabolischen Prozessen involviert sind. Wesentlich ist, dass trotz einer konstitutiven Aktivierung des TSHR Iod dennoch die Proliferation und Funktion einer frühzeitigen Schilddrüsenautonomie herabsetzt. Die physiologische Rolle des IGF-IR in der Schilddrüsenphysiologie in vivo wurde noch nicht systematisch erforscht. Um die Rolle des IGF-IR in der Schilddrüse im Hinblick auf deren Entwicklung und Metabolismus näher zu untersuchen, wurde ein Mausmodell generiert bei dem der IGF-IR schilddrüsenspezifisch über eine durch den TG Promoter regulierte Cre Rekombinase (Igf1rTgCre) ausgeschaltet wurde. Ziel war es nun zu untersuchen, welche Folgen ein thyreoidaler Igf1r Knockout auf die Funktion, Morphologie und Entwicklung der murinen Schilddrüse und metabolischer Parameter hat. Dieser Knockout zeigte in den Mäusen keine Veränderungen des Schilddrüsengewichtes und der Serum T3 Werte, wobei das Serum T4 nach 8 Wochen leicht absank, nach 4 Monaten aber wieder Normalwerte zeigte. Allerdings waren die Serum TSH Werte bis zu 9fach erhöht. Die Histologie der Igf1r-/- Mäuse zeigten mit einer Rate von 86% papilläre Schilddrüsenhyperplasien sowie eine starke Heterogenität der Follikelstruktur, die auch bei den Igf1r-/- Mäuse zu finden war. Die molekulare Kompensation des Igf1r Knockouts in der Schilddrüse besonders durch TSH konnte durch unsere Untersuchungen nicht hinreichend geklärt werden. Die Daten aus unseren Ergebnissen und eines reversen Mausmodells (Überexpression des IGF-IR und IGF-I) (Clement et al. 2001) weisen daraufhin, dass das IGF-IR Signal weniger essentiell für die Schilddrüsenhormonsynthese ist als für das Aufrechterhalten einer Homöostase und normaler Schilddrüsenmorphogenese.
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7

Pel, E. [Verfasser]. "Zum Verhalten von Iod im System Boden-Pflanze-Luft / E. Pel." Karlsruhe : KIT-Bibliothek, 1993. http://d-nb.info/114179246X/34.

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8

Gómez, Martín Juan Carlos. "Spectroscopic, kinetic and mechanistic studies of atmospherically relevant I2-O3 photochemistry." Berlin Logos-Verl, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=2927252&prov=M&dok_var=1&dok_ext=htm.

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9

Köhler, Fabian Matthias [Verfasser]. "Spektroskopische Untersuchungen und Speziation von Iod-129 in Umweltproben / Fabian Matthias Köhler." Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2020. http://d-nb.info/1209268833/34.

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10

Bayrhof, Markus. "Vergleich der Kontamination von Vorderkammerwasser nach Prophylaxe mit topisch appliziertem 0,5%-Levofloxacin und 1%-Iod-Povidon versus 1%-Iod-Povidon allein, bei Patienten, die sich einer intraokularen Operation unterziehen." Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-100718.

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11

Shaaban, Ahmed A. "Modulation of East African Precipitation by the Indian Ocean Dipole (IOD) and ENSO." Thesis, State University of New York at Albany, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1588004.

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Tropical East Africa is influenced by two main rainy seasons, during autumn and spring. During autumn, tropical East African precipitation is clearly influenced by Indian Ocean Dipole (IOD) and/or ENSO. During spring, there is no clear SST pattern in the Indian Ocean. The association between El Niño and positive IOD phases is much stronger than the association between La Niña and negative IOD during October and November. During October, the association between El Niño and wet condition over tropical eastern Africa is stronger than association between La Niña and dry conditions. During November, the association between positive IOD and eastern African precipitation is stronger than the association between La Niña and dry conditions.

During short wet phases (such as autumn) over eastern Africa, two anticyclones form in the lower troposphere with upper baroclinic structure. These anticyclones decay rapidly by December. These anticyclones are responsible for supplying East Africa with increased moisture.

Most strong positive IOD events are associated with wet outcomes over eastern Africa. Not all strong El Niño events lead to wet outcomes.

It is well known that during northern spring, precipitation over eastern Africa is not connected to any inter-annual SST modes of variability. During northern spring, SST in Indian Ocean is nearly always sufficiently high to sustain convection, however, convection is not always active. We found that precipitation over eastern Africa during spring is associated with a dipole pattern of outgoing longwave radiation anomaly (OLRA) not associated with SST variability.

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12

Kantoci, Silvia. "Anreicherung von Iod und Omega-3-Fettsäuren in der Karpfenproduktion durch Algen im Fischfutter." Diss., lmu, 2008. http://nbn-resolving.de/urn:nbn:de:bvb:19-91631.

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13

Kantoci, Silvia. "Anreicherung von Iod und Omega-3-Fettsäuren in der Karpfenproduktion durch Algen im Fischfutter." kostenfrei, 2008. http://edoc.ub.uni-muenchen.de/9163/.

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14

Power, Katherine. "Regional and local impacts of the ENSO and IOD events of 2015 and 2016 on the Indian Summer Monsoon - A Bhutan case study." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-193611.

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The Indian Summer Monsoon (ISM) plays a vital role in the livelihoods and economy of those living on the Indian subcontinent, including the small, mountainous country of Bhutan. The ISM fluctuates over varying temporal scales and its variability is related to many internal and external factors including the El Niño Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD). In 2015, a Super El Niño occurred in the tropical Pacific alongside a positive IOD in the Indian Ocean and was followed in 2016 by a simultaneous La Niña and negative IOD. These events had worldwide repercussions. However, it is unclear how the ISM was affected during this time, both at a regional scale over the whole ISM area and at a local scale over Bhutan. First, an evaluation of data products comparing ERA5 reanalysis, TRMM and GPM satellite, and GPCC precipitation products against weather station measurements from Bhutan, showed that ERA5 reanalysis was the most suitable product to investigate ISM change in these two years. Using the reanalysis datasets, it was shown that there was disruption to the ISM during this period, with a late onset of the monsoon in 2015, a shifted monsoon flow in July 2015 and in August 2016 and a late withdrawal in 2016. However, this resulted in neither a monsoon surplus nor deficit across both years but instead large spatial-temporal variability. It is possible to attribute some of the regional scale changes to the ENSO and IOD events, but the expected impact of a simultaneous ENSO and IOD events are not recognisable. This may be due to a supposed weakening of the ENSO/ISM relationship and it is likely that 2015/16 monsoon disruption was driven by a combination of factors alongside ENSO and the IOD, including varying boundary conditions, the Pacific Decadal Oscillation, the Atlantic Multi-decadal Oscillation, and more. At a local scale, the intricate topography and orographic processes ongoing within Bhutan further amplified or dampened the already altered ISM. Whilst ENSO and IOD driven monsoon variability can be recognised at a regional scale, a direct link between ENSO and IOD activity and changes to the monsoon at a local scale over Bhutan is hard to distinguish. It is unknown how the ISM, ENSO, and the IOD will evolve under a future changing climate and therefore this presents a concern to Bhutan with its inherent vulnerability to monsoon variability.
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15

Kusserow, Sabrina. "Totalsynthese und Aufklärung der Stereochemie von Kuhistanol C sowie Entwicklung neuer Oxidationsreaktionen mit Iod(VII) /." Berlin, 2008. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000252761.

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16

Tosch, Lübbert [Verfasser]. "Kontamination von Nord- und Ostsee mit langlebigem Iod-129 und anderen anthropogenen Radionukliden / Lübbert Tosch." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover, 2010. http://d-nb.info/1009414259/34.

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17

Einspieler, Ingo [Verfasser], Klemens M. [Akademischer Betreuer] Scheidhauer, and Markus [Akademischer Betreuer] Schwaiger. "Iod-131-SPECT-CT Hybridbildgebung im Vergleich zur planaren Iod-131-Ganzkörperszintigraphie nach Radioiodtherapie und in der Nachsorge von Patienten mit differenziertem Schilddrüsenkarzinom / Ingo Einspieler. Gutachter: Markus Schwaiger ; Klemens M. Scheidhauer. Betreuer: Klemens M. Scheidhauer." München : Universitätsbibliothek der TU München, 2013. http://d-nb.info/1035502747/34.

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18

Parsons, Katherine. "Not all droughts are equal: understanding the climate drivers of wind erosion (ENSO, SAM and IOD)." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/373953.

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Wind erosion is recognised as an important issue globally. It is of importance in Australia due to a large proportion of the continent being classed as arid to semi-arid. With increases in land use and projected increases in the frequency and intensity of drought periods in Australia, wind erosion may be seen to increase, intensify and expand across the continent. Additionally, increases in the severity of annual to inter-annual climate systems (such as the El Niño Southern Oscillation (ENSO), the Southern Annual Mode (SAM), the Indian Ocean Dipole (IOD)) and even in overarching decadal to inter-decadal climate systems (such as the Interdecadal Pacific Oscillation (IPO) and the Pacific Decadal Oscillation (PDO)) will result in the spatial and temporal impacts of wind erosion being altered over time. Variations in drought and climate systems are recognised to affect wind erosion in Australia due to their influences on precipitation and erosive wind systems. Literature in the field of drought, wind erosion and climate systems was reviewed with respect to framing the need for this dissertation. It was identified that although a detailed understanding of drought has been developed over time (including definitions, impacts and influences) there are still challenges associated with the lack of uniform definition and with measures of severity, scale and overall prediction. Few wind erosion studies have focused on the impact that drought may have (and its flow-on effects to other wind erosion variables such as vegetation), particularly with respect to changes in response to climate. Climate systems research presents another layer of complexity to measuring or predicting wind erosion in Australia. This dissertation explores the role of drought and climate systems in wind erosion in eastern Australia (over the past 100 years), comparing a calculation of the potential for wind erosion with actual wind erosion (AWE) measures. It selects and adapts a drought index suitable for use in wind erosion studies and estimates the wind erosion potential (WEP) of eight drought periods, incorporating measures of soil erodibility and wind erosivity. It also evaluates why actual wind erosion rates (according to three different measures) differ to results produced by the WEP and examines how climate systems (the ENSO, SAM and IOD) and synoptic-scale systems influence wind erosion during the drought periods. Two drought indices (rainfall deciles (RD) and the Standardized Precipitation Index (SPI)) were assessed according to seven criteria developed to evaluate the favourability of indices for use in wind erosion studies. The SPI was selected as the most favourable due to its ability to identify the start and end dates of drought, provide measures of drought intensity, magnitude and severity and best capture wind erosion activity. The SPI was adapted and enhanced for the calculation of WEP using established factors of drought, erodibility (vegetation cover) and erosivity (wind speed) and applied to historical data (over 100 years from the consolidation of 63 observer stations into 22 stations in eastern Australia. Differences in results were evident for northeastern Australia (NEA) and southeastern Australia (SEA), reflecting varying short and longer term climatic influences. At a localised level wind severity, vegetative cover types and geomorphological features were able to explain differences. Specific climate systems phases (negative ENSO, negative SAM and positive IOD) occurring drought periods were found to favour wind erosion activity (both in NEA and SEA). A combination lock of climate system phase and wind erosion risk was developed to provide a conceptual understanding of the influence of climate systems on wind erosion during drought periods in Australia. This conceptual approach is unique to this dissertation, constituting an original innovation in the field of wind erosion research during drought and climate system studies in general. Combinations of climate system phases and associated wind erosion risk were presented for eight combinatoric scenarios, with highest wind erosion risk associated with negative ENSO, negative SAM and positive IOD. These combinations were demonstrated to have differing impacts according to location on the Australian continent due to differing synoptic-scale system dominance (trough systems in the north and cold fronts in the south). This dissertation has confirmed the important role that climate systems have on wind erosion during drought periods in eastern Australia. Its results have new implications for research in the field of wind erosion. It demonstrates a method of measuring drought from a wind erosion perspective and develops a way of both estimating wind erosion potential risk and investigating wind erosion activity from the lens of climate systems. The combination lock approach to climate systems and wind erosion during drought periods provides a conceptual advance in the climatological and meteorological understanding of wind erosion activity (spatially and temporally). Furthermore, at a time when the future impacts of drought and climate systems are predicted to intensify in severity and spatial scale, this research could provide a way for aeolian geomorphologists and land managers to predict the risk of wind erosion occurrence.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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19

Moers, H. [Verfasser]. "Oberflaechenanalytische Untersuchungen zum Freisetzungsverhalten fluechtiger Spaltprodukte bei simulierten Kernschmelzunfaellen und zum Reaktionsverhalten von Iod mit Silberoberflaechen / H. Moers." Karlsruhe : KIT-Bibliothek, 2014. http://d-nb.info/1196577471/34.

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20

Vitkute, Milda [Verfasser]. "Effekte ausgewählter Konzentrationen von Povidon-Iod auf das Elektroretinogramm im Modell der isolierten und perfundierten Vertebratennetzhaut / Milda Vitkute." Tübingen : Universitätsbibliothek Tübingen, 2019. http://d-nb.info/1227963173/34.

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21

Köhler, Lena. "Radiotracer für die molekulare Bildgebung: Radiomarkierung von Inhibitoren der CDK4/6 mit den Radionukliden Iod-124 und Fluor-18." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-38369.

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Krebserkrankungen stellen in Deutschland die zweithäufigste Todesursache dar und die Anzahl der Neuerkrankungen nimmt stetig zu. Frühzeitige Diagnosen und Therapiemöglichkeiten sind daher dringend erforderlich. Cyklinabhängige Proteinkinasen (Cdk) spielen eine entscheidende Rolle bei der Regulation des Zellzyklus. Viele Tumore zeigen eine deregulierte Cdk4‑Aktivität und/oder ‑Expression. Insgesamt zeigen ca. 80% aller Tumore eine Fehlregulation der für den Zellzyklus zentralen Cdk4/CykD1/INK4/pRb/E2F Signalkaskade. Somit besitzen Cdks ein enormes therapeutisches Potential im Kampf gegen Krebs. Die spezifische Inhibierung der Cdks verhindert die Zellproliferation und damit das Tumorwachstum. In den letzten Jahren wurden verschiedenste Strukturklassen vorgestellt, die als Cdk4-Inhibitor wirken. Im Rahmen der Promotion sollen die Möglichkeiten einer funktionellen Tumordiagnose mittels cyklinabhängiger Kinasen untersucht werden. Die Entwicklung von radioaktiv markierten Inhibitoren der Cdk4/6 als Radiotracer und ihre radiopharmakologische Charakterisierung stellt dabei einen neuen Ansatz dar. Um die Rolle der Cdk4/6 im Zellzyklus von gesunden und deregulierten (z.B. Tumor-) Zellen aufzuklären, sollten mit Iod-124 und Fluor-18 markierte Inhibitoren eingesetzt werden, die hochselektiv diese Cdks blockieren. Zunächst wurden verschiedene Inhibitoren der Cdk4/6 und deren Vorstufen für die Radiomarkierung dargestellt. Die bereits aus den Vorarbeiten von VanderWel et al., 2005 und Toogood et al., 2001 bekannten Syntheserouten mussten dazu optimiert werden und für neue Verbindungen, wie die fluorethylierten Substanzen, wurden neue Reaktionswege gefunden. Die dargestellten Referenzverbindungen CKIA-E wurden anschließend mittels Durchflusszytometrie an den Zelllinien HT-29 und FaDu auf ihre inhibitorischen Wirkung untersucht. Die Untersuchungen der Verbindungen CKIA/B/E zeigte, dass ein Zellzyklusarrest unter Einwirkung der Inhibitoren erreichbar ist. Die weiteren Untersuchungen zur Radiomarkierbarkeit sowie die radiopharmakologische Evaluation sollten daher an den Verbindungen CKIA, CKIB und CKIE stattfinden. Die Darstellung der Verbindungen [124I]CKIA und [124I]CKIB erfolgte in zwei Schritten über die elektrophile Substitution durch regioselektive Destannylierung mit anschließender Entschützung der Seitenkette. Die Darstellung der fluorethylierten Verbindung erfolgte ebenfalls über eine Zweischrittsynthese beginnend mit der Synthese der prosthetischen Gruppe [18F]BFE aus der Tosylmarkierungsvorstufe. Die zur Markierung des sekundären Amins zur Auswahl stehenden prosthetischen Gruppen [18F]Fluorethyltosylat ([18F]FETos) und [18F]Bromfluorethan ([18F]BFE) wurden auf ihre Eignung untersucht, ebenso wie die Auswahl einer geeigneten Markierungsvorstufe für die Darstellung der prosthetischen Gruppe. Die optimierten Syntheserouten ermöglichten die Isolierung von ausreichenden Mengen an Produktaktivität für die radiopharmakologischen Untersuchungen. Es fanden, neben der Bestimmung der spezifischen Aktivität und der Lipophilie der Verbindungen, Zellaufnahmeuntersuchungen und Bestimmungen zur Stabilität der Verbindungen in vitro, ex vivo und in vivo statt. Die radioiodierten Verbindungen konnten des Weiteren zur Untersuchungen der Bioverteilung in normalen männlichen Wistar-Ratten eingesetzt werden. Für alle drei Verbindungen konnte eine sehr hohe in vitro-Stabilität festgestellt werden. Die Zellaufnahmeuntersuchungen zeigten vor allem für die Verbindungen [124I]CKIA und [124I]CKIB eine beträchtliche Zellaufnahme von über 1000% ID/mg Protein nach 2 h. Die Zellaufnahme der Verbindung CKIE ist geringer, sollte allerdings für eine in vivo-Anwendung ausreichend sein. Die Untersuchung der in vivo‑Stabilität der Verbindungen [124I]CKIA, [124I]CKIB und [18F]CKIE im Blut von Wistar Ratten ergab allerdings, dass alle Verbindungen schnell metabolisiert werden. Die Untersuchung der Bioverteilung der radioiodierten Verbindungen belegen eine in vivo Radiodeiodierung sowie eine hohe hepatobliliäre Auscheidungsrate. Im Hinblick auf eine Anwendung als Radiotracer konnten im Rahmen dieser Arbeit neue Erkenntnisse gewonnen werden. Die dargestellten Inhibitoren sind in der Lage am Zellmodell den Zellzyklusarrest in der G1-Phase zu induzieren. Eine Radiomarkierung der ausgewählten Strukturen liefert das Produkt mit reproduzierbarer Ausbeute in hoher radiochemischer Reinheit und ausreichender spezifischer Aktivität, allerdings ist eine Herstellung der fluorethylierten Verbindung unter GMP-Bedingungen nur schwer realisierbar. Die radiomarkierten Verbindungen zeigen eine hohe in vitro-Stabilität und werden energieabhängig in die Zelle aufgenommen. Anhand der Stabilitätsuntersuchungen in vivo wurde gezeigt, dass alle drei Verbindungen in vivo instabil sind und sehr schnell hepatobiliär eliminiert.
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22

Schedler, Kathrin Verfasser], Axel [Akademischer Betreuer] [Kramer, Axel Gutachter] Kramer, and Georg [Gutachter] [Daeschlein. "Charakterisierung von zehnprozentigem PVP-Iod als Referenzsubstanz im Prüfkörpertest / Kathrin Schedler ; Gutachter: Axel Kramer, Georg Daeschlein ; Betreuer: Axel Kramer." Greifswald : Ernst-Moritz-Arndt-Universität, 2018. http://nbn-resolving.de/urn:nbn:de:gbv:9-opus-20359.

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23

Schedler, Kathrin [Verfasser], Axel [Akademischer Betreuer] Kramer, Axel [Gutachter] Kramer, and Georg [Gutachter] Daeschlein. "Charakterisierung von zehnprozentigem PVP-Iod als Referenzsubstanz im Prüfkörpertest / Kathrin Schedler ; Gutachter: Axel Kramer, Georg Daeschlein ; Betreuer: Axel Kramer." Greifswald : Ernst-Moritz-Arndt-Universität, 2018. http://d-nb.info/115371292X/34.

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24

Kaufmann, R. [Verfasser]. "Oberflaechenanalytische Untersuchungen zum thermischen Verhalten von passivierten Zircaloy-4 Oberflaechen und Reaktionsverhalten von Iod an Zircaloy-4 Oberflaechen / R. Kaufmann." Karlsruhe : KIT-Bibliothek, 2015. http://d-nb.info/119662898X/34.

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25

Haubold, Kathrin [Verfasser], Dagmar [Akademischer Betreuer] Führer, Knut [Akademischer Betreuer] Krohn, and Ralf [Gutachter] Paschke. "Aspekte der Schilddrüsenphysiologie am Beispiel von Iod, TSHR und IGF-IR / Kathrin Haubold ; Gutachter: Ralf Paschke ; Dagmar Führer, Knut Krohn." Leipzig : Universitätsbibliothek Leipzig, 2013. http://d-nb.info/123836618X/34.

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26

Person, Helmut. "Zur Kristallstruktur und elektronischen Struktur neuer Verbindungen im System Lanthanid-Titan-Chalkogen-Iod mit einem Beitrag über Pr2Se[SiO4] und Sm2Te[SiO4] /." [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965445496.

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27

Brandl, Florian [Verfasser], Sabine [Akademischer Betreuer] Beuermann, and Diethelm [Akademischer Betreuer] Johannsmann. "Halbkontinuierliche Iod-Transfer-Emulsionspolymerisation von Vinylidenfluorid - Von der Prozessoptimierung und dem kinetischen Verständnis bis hin zur Synthese von Kern/Schalen-Partikeln / Florian Brandl ; Sabine Beuermann, Diethelm Johannsmann." Clausthal-Zellerfeld : Technische Universität Clausthal, 2019. http://d-nb.info/1231363053/34.

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28

Dörfel, Dorothea [Verfasser], Axel [Akademischer Betreuer] Kramer, Axel [Gutachter] Kramer, and Martin [Gutachter] Exner. "Antiseptische Wirksamkeit alkoholbasierter Antiseptika mit Zusatz von PVP-Iod oder Chlorhexidindigluconat auf die anaerobe und aerobe Hautflora der Schulterregion / Dorothea Dörfel ; Gutachter: Axel Kramer, Martin Exner ; Betreuer: Axel Kramer." Greifswald : Universität Greifswald, 2021. http://d-nb.info/1236693132/34.

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29

Saffar, Illyyne. "Machine learning to infer user behavior in 5G autonomic networks." Thesis, Rennes 1, 2020. http://www.theses.fr/2020REN1S039.

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L'idée développée dans cette thèse est d’utiliser le Machine Learning Deep Learning et l’analyse de données radio 3GPP pour estimer et prédire le comportement d'un utilisateur, en termes d'habitudes et de préférence d'usage des services mobiles d’un réseau 5G. Le caractère multidimensionnel du comportement de l'utilisateur rend son estimation complexe et reste actuellement un défi. On a donc étudié son estimation sous une approche innovante au regard de l'état de l'art. On a proposé de la réaliser au sein d'un système unifié qui estime en parallèle chaque dimension du comportement. En utilisant des méthodes basées sur l’apprentissage approfondi (deep learning) supervisé et hybride/semi-supervisé, on propose une solution pour la détection de l’environnement (Indoor/ Outdoor Detection (IOD)) et jusqu'à 8 classes d'environnement d’un utilisateur de téléphone portable. Nous proposons ensuite une solution permettant de détecter la catégorie de mobilité (Mobility Speed Profile (MSP) Detection) jusqu'à 8 profils de vitesses. Enfin, une solution innovante basée sur des algorithmes d’apprentissage profond dans une architecture multitâches permet d'estimer conjointement à la fois l'environnement et le profil de mobilité. La comparaison avec l'état de l'art a montré l'efficacité des méthodes proposées. Ce qui permet d'envisager leur utilisation par des opérateurs mobiles au sein de leurs futurs
The main idea of this thesis is to use machine learning/deep learning techniques to estimate and predict user behavior by analyzing 3GPP radio signals. The user behavior is defined in terms of habits and preferences while consuming 5G services. The estimation of user behavior is complex and remains a challenge due to its multidimensional nature. We therefore studied an innovative approach for the user behavior estimation: we use a unified system which jointly as well as parallelly estimates each dimension of behavior. Using methods based on supervised and hybrid / semi-supervised deep-learning, we propose a solution for the detection of the user environment (from Indoor/ Outdoor Detection (IOD) to up to 8 classes). We then propose a solution to detect the mobility categories (Mobility Speed Profile (MSP) Detection) up to 8 speed profiles. Finally, an innovative solution jointly estimates both the environment and the mobility profile using deep learning algorithms and a multitasking architecture. The comparison with the state of the art shows the effectiveness of the proposed methods. This allows to consider its deployment by operators in future
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Valiya, Parambil Akhil. "Apport des données spatiales pour la modélisation numérique de la couche de mélange du Golfe du Bengale." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30333/document.

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Le Golfe du Bengale (GdB), dans l'océan indien Nord, est sous l'influence d'intenses vents de mousson, qui se renversent saisonnièrement. Les fortes pluies et les apports fluviaux associés à la mousson de Sud-Ouest font du GdB l'une des régions les moins salées des océans tropicaux. La forte stratification haline proche de la surface qui en découle contribue à limiter le mélange vertical, ce qui maintient des températures de surface élevées et favorise la convection atmosphérique et les pluies. Cette stratification en sel a ainsi des implications profondes sur les échanges air-mer et sur le climat des pays riverains. L'objectif de ma thèse est d'améliorer la description de la variabilité de la salinité de surface (SSS) du GdB, et de comprendre ses mécanismes aux échelles de temps saisonnières à interannuelles. Les climatologies existantes ont permis de mettre en évidence un cycle saisonnier marqué de la SSS, avec un dessalement intense de la partie Nord du bassin pendant l'automne, suivi par une expansion de ces eaux dessalées le long du bord Ouest du bassin. Cette langue dessalée s'érode finalement pendant l'hiver, pour revenir à son extension minimale au printemps. Cependant, la rareté des observations in-situ de SSS ne permet d'observer les fluctuations interannuelles autour de ce cycle saisonnier que de manière parcellaire dans le GdB. Le développement récent de la télédétection spatiale de la SSS (missions SMOS et AQUARIUS) a ouvert de nouvelles opportunités à cet égard. Cette technologie reste toutefois délicate dans le cas d'un bassin de petite taille tel que le GdB, du fait des contaminations éventuelles du signal de SSS par les interférences radio et par les sources d'origine continentale. Une validation systématique des produits satellites par comparaison à un jeu de données in-situ exhaustif montre qu'Aquarius capture de façon réaliste les évolutions saisonnières et interannuelles de la SSS partout dans le GdB. A l'inverse, SMOS ne parvient pas à restituer une salinité meilleure que les climatologies existantes
Located in the Northern Indian Ocean, the Bay of Bengal (BoB) is forced by intense seasonally reversing monsoon winds. Heavy rainfall and strong river runoffs associated with the southwest monsoon makes the bay one of the freshest regions in the tropical ocean. This surface fresh water flux induces strong near surface salinity stratification, which reduces vertical mixing and maintains high sea surface temperatures and deep atmospheric convection and rainfall. This intense near surface haline stratification has therefore profound implications on the air-sea exchanges, and on the climate of the neighboring countries. The goal of my thesis is to improve the description of the Sea surface salinity (SSS) variability in the BoB and to understand the oceanic and atmospheric processes driving this variability at seasonal and interannual timescales. Existing climatologies reveal a marked seasonal cycle of SSS with an intense freshening of the northern part of the basin during fall that subsequently spreads along the western boundary. This fresh pool finally erodes during winter, to reach its minimal extent in spring. The paucity of in-situ SSS observations however prevented to monitor the interannual fluctuations around this seasonal picture with a good spatial coverage. The recent development of SSS remote-sensing capabilities (with SMOS and AQUARIUS satellites) may help with that regard. However this is particularly challenging for a small semi-enclosed basin such as the Bay of Bengal, because of the potential contamination of the SSS signal by radio frequency interferences and land effects in the near coastal environment. A thorough validation of these satellite products to an exhaustive gridded in-situ dataset shows that Aquarius reasonably captures the large-scale observed seasonal and interannual SSS evolution everywhere in the BoB while SMOS does not perform better than existing climatologies, advocating for improvements of its SSS retrieval algorithm there
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Patzelt, Christoph Verfasser], Tanja [Akademischer Betreuer] [Gutachter] [Gulder, and Wolfgang [Gutachter] Eisenreich. "Iod(III)-katalysierte, direkte Umwandlung von Imiden zu beta-Lactamen und Derivaten und Design, Synthese und Evaluierung fluorhaltiger Verbindungen als Kontrastmittel für Anwendungen in der 19F-MRT / Christoph Patzelt ; Gutachter: Tanja Gulder, Wolfgang Eisenreich ; Betreuer: Tanja Gulder." München : Universitätsbibliothek der TU München, 2016. http://d-nb.info/1115856421/34.

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Mehari, Symon [Verfasser], Johannes [Akademischer Betreuer] Meller, Andrea [Akademischer Betreuer] Hille, and Patricia [Akademischer Betreuer] Virsik-köpp. "Hochdosis-Chemotherapie gefolgt von einer myeloablativen Hochdosis-Radioimmuntherapie (HD-RAIT) mit Iod-131-Rituximab und peripherer Stammzelltransplantation (SCTx) bei primär refraktären und rezidivierten Non-Hodgkin-Lymphomen / Symon Mehari. Gutachter: Johannes Meller ; Andrea Hille ; Patricia Virsik-Köpp. Betreuer: Johannes Meller." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2011. http://d-nb.info/104269057X/34.

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33

Alinder, Simon. "Space Situational Awareness with the Swedish Allsky Meteor Network." Thesis, Uppsala universitet, Observationell astrofysik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-390397.

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This thesis investigates the use of the Swedish Allsky Meteor Network (SAMN) for observing, identifying, and determining the orbits of satellites. The overall goal of this project is to determine the feasibility of using such a network for Space Situational Awareness (SSA) purposes, which requires identification and monitoring of objects in orbit. This thesis is a collaboration with the Swedish Defense Research Agency (FOI) to support their efforts in SSA. Within the frame of this project, the author developed software that can take data of observations of an object collected from the all-sky cameras of SAMN and do an Initial Orbit Determination (IOD) of the object. An algorithm that improves the results of the IOD was developed and integrated into the software. The software can also identify the object if it is in a database that the program has access to or, if it could not be identified, make an approximate prediction of when and where the object will be visible again the next time it flies over. A program that analyses the stability of the results of the IOD was also developed. This measures the spread in results of the IOD when a small amount of artificial noise is added to one or more of the observed coordinates in the sky. It was found that using multiple cameras at different locations greatly improves the stability of the solutions. Gauss' method was used for doing the IODs. The advantages and disadvantages of using this method are discussed, and ultimately other methods, such as the Gooding method or Double R iteration, are recommended for future works. This is mostly because Gauss' method has a singularity when all three lines of sight from observer to object lie in the same plane, which makes the results unreliable. The software was tested on a number of observations, both synthetic and real, and the results were compared against known data from public databases. It was found that these techniques can, with some changes, be used for doing IOD and satellite identification, but that doing very accurate position determination required for full orbit determination is not feasible.
Detta examensarbete undersöker möjligheterna att använda ett svenskt nätverk av allskykameror kallat SAMN (Swedish Allsky Meteor Network) för att observera, identifiera och banbestämma satelliter. Det övergripande målet med detta projekt är att bestämma hur användbart ett sådant nätverk skulle vara för att skapa en rymdlägesbild, vilken i sin tur kräver bevakning och identifikation av objekt som ligger i omloppsbana. Detta examensarbete är ett samarbete mellan Uppsala Universitet och FOI (Totalförsvarets Forskningsinstitut). Inom ramen för detta projekt har författaren utvecklat mjukvara som kan ta data från observationer av objekt utförda av SAMN och göra initiala banbestämningar av objekten. En algoritm som förbättrar resultaten av den initiala banbestämningen utvecklades och integrerades i programmen. Programmen kan också identifiera satelliter om de finns med i en databas som programmet har tillgång till eller förutsäga objektets nästa passage över observatören om det inte kunde identifieras. Ett annat program som analyserar känsligheten av resultaten av den initiala banbestämningen utvecklades också. Detta program mäter spridningen i resultat som orsakas av små störningar i de observerade koordinaterna på himlen. Det framkom att stabiliteten av resultaten kan förbättras avsevärt genom att använda flera observatörer på olika orter. I detta projekt användes Gauss metod för att göra banbestämningarna. Metodens för- och nackdelar diskuteras och i slutänden rekommenderas istället andra metoder, som Goodings metod eller Dubbel R-iteration, för framtida arbeten. Detta beror mest på att Gauss metod innehåller en singularitet när alla siktlinjer från observatören till objektet ligger i samma plan som varandra vilket gör resultaten opålitliga i de fallen. Programmen testkördes på ett antal olika observationer, både artificiella och verkliga, och resultaten jämfördes med kända positioner. Slutsatsen av arbetet är att de undersökta teknikerna kan, med vissa modifikationer, användas för att göra initiala banbestämningar och satellitidentifikationer, men att göra de väldigt precisa positionsbestämningarna som krävs för fullständig banbestämning är inte genomförbart.
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Citron, Albert. "Hidden in Plain Sight: Development and Testing of a Model to Evaluate Political Leadership Tactics." Master's thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5918.

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This thesis analyzes the kinds of verbal and nonverbal signals elites manifest to show leadership qualities. Launching from Max Weber's conceptual framework of charisma as a power term and Harold Lasswell's study of propaganda, this study takes a multidisciplinary approach to studying political leadership with elements of communication methodology and an ontological basis in evolutionary psychology. The study's goal is to offer a framework for defining and evaluating the diverse signal patterns employed by political elites in three real-life situations. These are the Malta Summit, the 1992 Virginia Presidential Debate, and the 2012 South Carolina Republican Presidential Primary. The cases were chosen because they display a diverse set of signal variations during different types of interactions. The three case studies are evaluated by measuring frequency and patterns of occurrence of the five different interaction constructs (indicator of interest, indicator of disinterest, demonstration of high value, demonstration of low value, and compliance testing) to explain different interaction patterns. A simple frequency distribution of the different signals during a given interaction is used to display the empirical findings and to compare patterns across the case studies. This study reveals that the presence of DLV (demonstration of low value) signals weaken an elite's position in relation to other elites and the public while the presence of DHV (demonstration of high value) signals strengthen an elite's position. It is largely the presence, absence, and frequency of these two signals that determines who conveys leadership qualities effectively regardless of leadership style. Studying the signaling patterns of political elites would allow scholars to understand better the kinds of signal patterns and signal frequencies that are used in different types of leadership styles and norm ranges for signals including for political elites belonging to different cultures and subcultures.
M.A.
Masters
Political Science
Sciences
Political Science; International Studies
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CHRISTOFORAKIS, IOANNIS. "Protection and safety framework for on-chip communications and Mixed-Critical Cyber-Physical Systems." Doctoral thesis, Università Politecnica delle Marche, 2020. http://hdl.handle.net/11566/279598.

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L'Internet of Things (IoT), una rete globale emergente di dispositivi elettronici embedded identificabili in modo univoco all'interno della rete Internet, sta trasformando il modo in cui viviamo e lavoriamo aumentando la connessione di persone e cose su una scala che un tempo era inimmaginabile. Oltre a una maggiore efficienza di comunicazione tra gli oggetti connessi, l'IoT comporta anche nuove sfide in termini di sicurezza e privacy. La specifica della sicurezza deve essere implementata in dispositive IoT che hanno il vincolo di memoria limitata, middleware vincolato, bassa potenza di calcolo e basso consumo. La sicurezza è uno degli aspetti fondamentali che differenzia l’IoT dai generici dispositivi embedded. L'implementazione hardware su circuito integrato di diverse funzionalità di sicurezza migliora la protezione di un sistema implementando il controllo degli accessi a risorse critiche, il rilevamento di manomissioni e guasti, la protezione dei canali laterali e la protezione contro il reverse engineering e il furto di IP. La presente tesi ha come obiettivo la definizione di una metodologia di progettazione hardware che garantisca sicurezza e protezione. Questa metodologia è stata implementata in un framework sviluppato per estendere le capacità del sistema al controllo delle minacce alla sicurezza del sistema attraverso una protezione a livello hardware. In questa tesi presentiamo il framework dell'architettura hardware, che combina la TAMMU (Translation and Allocation Memory Management Unit) utilizzata in SoC eterogenei che supportano la virtualizzazione integrata con un'architettura di protezione hardware (MSU). Questi miglioramenti hardware si concentrano sull'isolamento dei compartimenti della memoria fisica applicando regole di accesso. Il framework, pertanto, consente l'applicazione di politiche dinamiche di sicurezza sull'hardware per la protezione da componenti hardware o software non affidabili. D'altra parte, nelle Networks-on-Chip la velocità di iniezione del traffico è gestita principalmente impiegando tecniche complesse. Questo lavoro propone un Traffic Shaper Module che supporta sia il monitoraggio che il controllo del traffico sull'interfaccia di rete su chip o sul controller di memoria. Il vantaggio di questo Traffic Shaper Module è che garantisce una larghezza di banda di memoria alle applicazioni critiche limitando il traffico di attività non critiche. Il sistema è sviluppato hardware Xilinx ZYNQ7000 system-on-chip, mentre le misurazioni sono state acquisite su una scheda di sviluppo Xilinx Zed-board. Abilitando il Traffic Shaper nella nostra architettura, abbiamo raggiunto il controllo della larghezza di banda con un sovraccarico trascurabile, fornendo allo stesso tempo una larghezza di banda dello 0,5-5 per cento in meno rispetto alla larghezza di banda teorica specificata. L'architettura TAMMU proposta offre funzionalità innovative uniche che supportano più istanze di macchine virtuali (VM) simultaneamente attive con commutazione del contesto con latenza zero e abilitando i servizi di traslazione degli indirizzi per un massimo di mille domini virtuali mentre servono più dispositivi. Allo stesso tempo, il progetto proposto consente di soddisfare più richieste di traslazione di indirizzi in parallel e una in invalidazione per dominio del Translation Look-aside Buffer (TLB). L’architettura proposta è innovative rispetto allo stato dell’arte in quanto combina i servizi di enabling address translation con una larghezza di banda di memoria garantita e protesione della memoria. L’implementazione sulla piattaforma programabile FPGA Xilinx XC5VLX110T ha permesso il confronto con architetture alternative. La tesi è organizzata nel seguente modo: lo stato dell’arte è presentato nell’introduzione. Le caratteristiche del framework proposto sono descritte nella Sezione 2. La viosione generale del Sistema è presentato nella Sezione 3. La Sezione 4 riporta il test del sistema con la valutazione delle performances e le risorse richieste. Un confronto con le prestazioni di altre architetture è presentato nella Sezione 5.Un esempio applicativo sull’healtcare è presentato nella Sezione 6. Infine, la Sezione 7 riporta le conclusioni.
The Internet of Things (IoT), an emerging global network of uniquely identifiable embedded computing devices within the existing Internet infrastructure, is transforming how we live and work by increasing the connectedness of people and things on a scale that was once unimaginable. In addition to increased communication efficiency between connected objects, the IoT also brings new security and privacy challenges. The security requirements for the huge base of connected embedded devices are distinct on account of their limited memory, constrained middleware, and low computing power. Security is the new differentiator for embedded and IoT devices. At the on-chip level, several security features enhance the protection of a system by implementing access control to critical resources, by tamper and fault detection, by side-channel protection, and by protection against reverse engineering and IP theft. The thesis targets the design of on-chip system by implementing a methodology that ensures safety and security by design. This methodology is enabled by a framework developed to extend system capabilities so as to control the concurrent effects of security threats on the system behavior focusing on hardware level protection. We present the hardware architecture Framework, that combines Translation and Allocation Memory Management Unit (TAMMU) utilized in heterogeneous SoCs that support full virtualization integrated with a hardware protection architecture (MSU). These hardware enhancements focus on isolating physical memory compartments by applying access rules; thus, we allow dynamic security policies to be enforced at the hardware for protection against untrustworthy hardware or software components. On the other hand, Networks-on-Chip manage the traffic injection rate mainly by employing complex techniques; either back-pressure based low-control mechanisms or rate-control of traffic load (i.e. traffic shaping). This work proposes such a Traffic Shaper Module that supports both monitoring and traffic control at the on-chip network interface or the memory controller. The advantage of this Traffic Shaper Module is that proposed security framework provides guaranteed memory bandwidth to the critical applications by limiting traffic of non-critical tasks. The system is developed in the Xilinx ZYNQ7000 System-on-Chip while the measurements were captured on a Zed-board development board. By enabling the Traffic Shaper in our architecture, we achieved ne-grain bandwidth control with negligible overhead, while providing bandwidth of only 0.5-5 percent less than the theoretical specified bandwidth The proposed TAMMU architecture offers unique innovative features supporting multiple concurrently active virtual machine instances (VMs) with zero-latency world-context switching and enabling address translation services for up to a thousand virtual domains while serving multiple devices. At the same the proposed design allows for serving multiple address translation requests in parallel and per domain Translation Look-aside Buffer (TLB) invalidation. Proposed architecture is innovative in relation to the state of the art as it combines enabling address translation services with the capability that the proposed security framework provides guaranteed memory bandwidth and memory protection. The combination of these two complex features is not supported in previous systems. We prove that despite the increased need for hardware, our design manages to keep resource utilization at least at the same level as other known technologies implemented in modern systems. Significant differentiation, favorable to our architecture, is also achieved in performance compared to the state of the art. The need for comparisons with alternative architectures made it necessary to integrate our system into the Xilinx XC5VLX110T FPGA platform as well. The thesis is organized as follows. An overview of state of the art is given in Introduction section. The techniques that our framework include and its features are described in Section 2, followed by full system overview in Section 3. In Section 4, the testing of Framework and the performance and resource requirements are discussed. In Section 5, comparison with the State of the Art presented. A healthcare example is given in Section 6. Finally, Section 7 concludes the thesis.
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Graf, Franziska. "Die Cyclin-abhängigen Kinasen 4 und 6 als Zielproteine für die Therapie und Bildgebung von Tumoren." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-38909.

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Die Cyclin-abhängigen Kinasen 4 und 6 (Cdk4/6) wurden als essentielle Enzyme für die Regulation des Zellzyklus mit kritischem Beitrag zur gestörten Zellproliferation während der Kanzerogenese identifiziert. Als Konsequenz davon erwiesen sich die Cdk4/6 als attraktive Zielproteine für die Entwicklung neuer therapeutischer Konzepte zur pharmakologischen Tumorbehandlung. Verbindungen aus der Substanzklasse der Pyrido[2,3-d]pyrimidine zeigten vielversprechende inhibitorische Wirkungen auf die Aktivität der Cdk4/6 bei gleichzeitiger herausragender Selektivität gegenüber anderen Cdk. Anschließende Untersuchungen in vitro und in vivo verdeutlichten das Potential einiger Pyrido[2,3 d]pyrimidine zur Inhibierung des Tumorzellwachstums. Die Weiterentwicklung und Nutzung selektiver Cdk4/6-Inhibitoren zur funktionellen Charakterisierung der Cdk4/6 in Tumoren in vivo mit Hilfe der nicht-invasiven Bildgebungstechnik Positronen-Emissions-Tomographie (PET) ist ein neuer vielversprechender Forschungsansatz und von großem Interesse für die Evaluierung neuer Strategien zur Diagnose und Therapie maligner Erkrankungen. Das Ziel der vorliegenden Arbeit ist die biochemische und radiopharmakologische Charakterisierung neuer potentieller Cdk4/6-Inhibitoren aus der Verbindungsklasse der Pyrido[2,3-d]pyrimidine und deren Bewertung hinsichtlich ihrer therapeutischen Wirksamkeit zur gezielten Cdk4/6-Inhibierung in ausgewählten Tumorzelllinien sowie ihres Potentials zur funktionellen Bildgebung der Cdk4/6 in Tumoren mittels PET am Tiermodell. Die biochemische Charakterisierung der Pyrido[2,3 d]pyrimidine CKIA, CKIB, CKIC, CKID und CKIE hinsichtlich ihrer zellulären und molekularen Wirkung erfolgte in den kontinuierlich proliferierenden humanen Tumorzelllinien HT-29, FaDu und THP 1 und in differenzierten THP-1-Makrophagen. Die Zweckmäßigkeit der untersuchten Zelllinien zur Charakterisierung potentieller Cdk4/6-Inhibitoren wurde anhand von Studien zur mRNA-Expression und Proteinbiosynthese der Kinasen Cdk4/6 nachgewiesen. Des Weiteren wurde das Vorkommen der Cdk4/6 in den humanen Xenograft-Tumoren HT-29 und FaDu, sowie in ausgewählten Organen und Geweben von nu/nu-NMRI-Mäusen charakterisiert. In vitro wurden für alle untersuchten Pyrido[2,3-d]pyrimidine signifikante, konzentrations- und zeitabhängige inhibitorische Effekte auf die Tumorzellproliferation beobachtet. Durchflusszytometrische Zellzyklusanalysen 24 Stunden nach Inkubation mit den Pyrido[2,3 d]pyrimidinen zeigten eine konzentrationsabhängige Zunahme des Anteils der HT-29-, FaDu- und THP-1-Zellen in der G1-Phase bis auf 90%. Für die nicht-proliferierenden THP 1-Makrophagen wurden bei Inkubation mit den Pyrido[2,3 d]pyrimidinen geringe Veränderungen ihrer Zellzahl und Zellzyklusphasen-verteilung detektiert. Die zellulären Studien identifizierten deutliche qualitative und quantitative Unterschiede der untersuchten Pyrido[2,3 d]pyrimidin-Derivate. Nanomolare Konzentrationen von CKIA, CKIB bzw. CKIE erzielten bereits 24 Stunden nach Inkubation deutliche Effekte, während für CKIC und CKID die 10- bis 100-fache Konzentration eingesetzt werden musste, um eine ähnliche Wirkung zu erhalten. Die molekularen Ursachen der Wachstumshemmung und des Zellzyklusarrests wurden durch Untersuchungen zur Pyrido[2,3 d]pyrimidin-abhängigen Beeinflussung des Cdk4/6-Cyclin D-Retinoblastom-E2F-Signalwegs geklärt. In allen Zelllinien wurde eine deutliche Inhibierung der Cdk4/6-spezifischen Phosphorylierung der Aminosäure Serin-780 des Retinoblastom-Proteins (pRb) beobachtet. Als Konsequenz dieser Inhibierung wurde für CKIA, CKIB und CKIE die signifikante konzentrationsabhängige Unterbrechung der Genexpression von E2F-1 und PCNA nachgewiesen. Die Radiomarkierung der Cdk4/6-Inhibitoren CKIA und CKIB mit 124I bzw. von CKIE mit 18F ermöglichte erstmals die Charakterisierung von in vivo-Interaktionen und des Metabolismus im Blut zirkulierender Pyrido[2,3 d]pyrimidin-Derivate. Die radiopharmako-logischen Eigenschaften von [124I]CKIA, [124I]CKIB und [18F]CKIE wurden in Untersuchungen zur zellulären Radiotracer-Aufnahme, der metabolischen Stabilität und der Bioverteilung bei Ratten sowie abschließend in Kleintier-PET-Untersuchungen bei FaDu-Tumor-tragenden nu/nu-NMRI-Mäusen analysiert. In vitro-Experimente mit [124I]CKIA, [124I]CKIB und [18F]CKIE verdeutlichten eine hohe Stabilität und schnelle Aufnahme der Radiotracer in humane Tumorzellen bei 37°C. Allerdings deutet die Zelltyp-unabhängige Anreicherung auf eine geringe Abhängigkeit der Pyrido[2,3 d]pyrimidin-Akkumulation vom Cdk4/6-Status der Zellen hin. Die signifikant geringeren Aufnahmewerte aller untersuchten Pyrido[2,3-d]pyrimidine bei 4°C und die Blockierung der Aufnahme von [18F]CKIE mit nichtradioaktivem CKIE unterstützen die Vermutung spezifischer Transportmechanismen für die Aufnahme der Pyrido[2,3 d]pyrimidine. Untersuchungen von [124I]CKIA, [124I]CKIB und [18F]CKIE in vivo identifizierten eine schnelle, innerhalb weniger Minuten stattfindende Eliminierung aus dem Blut und die primäre Aufnahme in die Leber als grundlegende Stoffwechseleigenschaft aller drei Radiotracer. Aus den PET-Untersuchungen mit [124I]CKIA und [124I]CKIB bei FaDu-Tumor-tragenden Mäusen wurden nur marginale Anreicherungen der radioaktiven Substanzen im Bereich des Tumors festgestellt. Für [18F]CKIE wurde eine Akkumulation im proliferierenden Randbereich des Tumors beobachtet. Die schnelle Metabolisierung von [18F]CKIE im Blut sowie das konstante, geringe Verhältnis der Aktivität im Tumor zur Aktivität im Skelettmuskel wiesen allerdings auf eine unspezifische Anreicherung hin. Schlussfolgernd aus den Ergebnissen der vorliegenden Arbeit wurde die Effektivität der Pyrido[2,3 d]pyrimidine CKIA, CKIB und CKIE hinsichtlich der Inhibierung der Cdk4/6-vermittelten Zellzyklusprogression gezeigt. Die antiproliferative Aktivität der Substanzen unterstützt eine weiterführende Evaluierung dieser Cdk4/6-Inhibitoren zur pharmakologischen Tumortherapie. Auf der Basis der erhaltenen radiopharmakologischen Ergebnisse werden die kurze biologische Halbwertszeit und unspezifische Tumoranreicherung von [124I]CKIA, [124I]CKIB und [18F]CKIE als limitierende Faktoren für die Eignung dieser Verbindungen als Radiotracer zur nicht-invasiven Bildgebung der Cdk4/6 im Zielgewebe mittels PET angesehen. Es bleibt zu klären, ob eine längere Verweildauer und höhere Stabilität radiomarkierter Pyrido[2,3-d]pyrimidine im Blut die Chance der Cdk4/6-spezifischen Gewebeanreicherung erhöhen oder Transport-mechanistische Effekte allein ausschlaggebend für die Anreicherung in Zellen und Geweben sind. Die Untersuchung optimierter Cdk4/6-selektiver Inhibitoren für die Charakterisierung und Therapie von Tumoren bleibt weiterhin ein interessanter Aspekt in der Tumorforschung.
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37

Höfig, Carolin. "Establishment, validation and application of immunological and LC-MS/MS-based detection methods to study the role of human aromatic L-amino acid decarboxylase as an enzyme potentially involved in thyronamine biosynthesis." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2012. http://dx.doi.org/10.18452/16645.

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Thyronamine (TAM) sind eine neue Molekülklasse, die endokrinologische und metabolische Prozesse miteinander vereinen. Der biologisch aktive Metabolit 3-Iod-L-Thyronamin (3-T1AM) wird durch eine kombinierte Deiodierung und Decarboxylierung von Schilddrüsenhormonen (TH) gebildet. Existierende Methoden zum Nachweis und zur Quantifizierung von 3-T1AM im menschlichen Serum sind immer noch umstritten. Auch die an der Biosynthese vermutlich beteiligte TH-Decarboxylase konnte noch nicht identifiziert werden. Für die Identifizierung und Quantifizierung von TH und TAM Profilen wurde die Flüssigchromatographie-Tandem-Massenspektrometrie (LC-MS/MS) verwendet. In der bisherigen präanalytischen Aufarbeitung liefern weder Flüssig-Flüssig- noch Festphasenextraktionen reproduzierbare Ergebnisse des 3-T1AM-Gehalts im Serum. Mit der Entwicklung eines spezifischen Extraktionsverfahrens und nachfolgender Detektion mittels LC-MS/MS gelang der gleichzeitige Nachweis der häufigsten TH im humanen Serum. Parallel dazu wurden monoklonale Antikörper gegen 3-T1AM entwickelt, auf deren Basis ein quantitativer 3-T1AM Chemilumineszenz-Immunoassay entstand. Ergebnisse aus klinischen Kollektiven zeigen, dass 3-T1AM im Serum im nM Konzentrationsbereich vorkommt und dass 3-T1AM bei Patienten außerhalb der Schilddrüse produziert wird. Viele Forscher gehen davon aus, dass die aromatische L-Aminosäure Decarboxylase (AADC) die Synthese von TAM über Decarboxylierung von TH katalysiert. Diese Hypothese wurde durch Inkubation von rekombinanter humaner AADC mit TH getestet. In keinem der Experimente konnte AADC die Decarboxylierung von TH katalysieren. Zusammenfassend ist die Bestimmung von 3-T1AM im Serum mittels LC-MS/MS aufgrund der nicht reproduzierbaren präanalytischen Probenaufbereitung problematisch. In dieser Arbeit wird der erste MAb-basierte 3-T1AM assay vorgestellt, der 3-T1AM zuverlässig in humanem Serum quantifiziert. Die AADC ist wahrscheinlich nicht an der Biosynthese von TAM beteiligt.
Thyronamines (TAM) are a new class of molecules linking endocrinology and metabolism. Combined deiodination and decarboxylation of thyroid hormones (TH) generates a biologically active ‘cooling’ metabolite, 3-iodo-L-thyronamine (3-T1AM).. It remains controversial, which methods are able or not to reliably detect 3-T1AM in human serum, and the presumed TH decarboxylase is still elusive. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used for the simultane-ous identification and quantification of TH and TAM profiles in biological samples. Several preanalytical methods were tested for complete extraction of 3-T1AM in human serum. Thus far, neither liquid-liquid nor solid-phase extraction methods allowed reproducible extraction of 3-T1AM from human serum samples in the preanalytical sample workup. Nevertheless, a rapid and sensitive extraction procedure was developed for detection of the major TH by LC-MS/MS in a single human serum sample. In parallel, monoclonal antibodies (MAb) targeting 3-T1AM were developed and characterized, and a highly specific quantitative 3-T1AM MAb-based chemiluminescence immunoassay was developed. Studies in clinical cohorts provide evidence that 3-T1AM is present in human serum in the nM concentration range and that 3-T1AM is produced extrathyroidally. Many researchers have reasoned that the aromatic L-amino acid decarboxylase (AADC) mediates TAM synthesis via decarboxylation of TH. This hypothesis was tested by incubating recombinant human AADC with several TH. In all tested conditions, AADC failed to catalyze the decarboxylation of TH. These in vitro observations are supported by the finding that 3-T1AM is also present in plasma samples of patients with AADC deficiency. In summary, 3-T1AM detection in serum using LC-MS/MS encounters preanalytical problems. The first MAb-based 3-T1AM CLIA is presented, which reliably quantifies 3-T1AM in human serum. AADC is likely not involved in TAM biosynthesis.
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38

Foriel-Destezet, Caroline. "Le traitement du phéochromocytome malin par la métaiodobenzylguanidine marquée à l'iode 131 : à propos d'un cas." Montpellier 1, 1992. http://www.theses.fr/1992MON11207.

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39

Hughes, Ian G. "Electron ion and ion-ion collisions." Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335410.

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40

LUBRANO, PASCALE. "Le traitement des tumeurs carcinoides : place de la 131i-mibg : a propos de 2 observations." Lyon 1, 1994. http://www.theses.fr/1994LYO1M050.

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41

Hloušek, Martin. "iPad and its potential in education." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-73622.

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This master thesis focuses on the Apple's iPad in the educational institutions and provides reader with the compact overview about the device in this field. Firstly, it shows the strategy of the company in the Europe and the Czech Republic. Secondly, there are mentioned iPad competitors from the different perspectives and the comparison. Thirdly, iPad usage in the schools; if it is even suitable device for this field and how students and educators can benefit from it. This is followed by the survey among the high school and university students. The questionnaire was divided into the two groups -- non-iPad users and iPad users. And lastly the thesis shows various case studies from the different schools and how the iPad can be implemented into the curriculums. Also contains recommendations and the best practises from the different high schools and universities, which can be inspiring for the new iPad pilot projects.
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42

Marie, Pierre-Yves. "Évaluation de la viabilité myocardique par un acide gras beta-méthyle marque par l'iode-123 : étude réalisée chez l'homme et sur un modèle de cœur isolé perfusé de lapin." Nancy 1, 1996. http://www.theses.fr/1996NAN10373.

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43

Ljunggren, Anette. "Effekter av EDI i interorganisatoriska relationer." Thesis, University of Skövde, Department of Computer Science, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-435.

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EDI står för elektroniskt utbyte av data från dator till dator och sker mellan kända affärspartners. När EDI införs i en relation mellan två organisationer anses relationen bli mer komplex än tidigare. Syftet med detta arbete är därför att undersöka hur EDI påverkar interorganisatoriska relationer.

Undersökningen utförs genom att studera affärsrelationerna mellan en offentlig förvaltning och tre av dess leverantörer. I dessa relationer studeras speciellt hur förhandlingsstyrkan, flexibiliteten och tillförlitligheten har påverkats av att EDI har börjat användas för den offentliga förvaltningens inköpsprocess.

De slutsatser som dras är att de undersökta faktorerna förändras i takt med att EDI blir alltmer integrerat i affärsrelationerna. Initialt byggs vissa omställningskostnader upp, som ökar leverantörernas förhandlingsstyrka. När EDI-kommunikationen fungerar kan kunden komma att öka sin förhandlingsstyrka på grund av bättre informationsdelning och något större inköpsvolymer hos leverantören. Flexibiliteten har ännu inte förändrats nämnvärt, medan tillförlitligheten i leveranserna har ökat till följd av EDI.

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44

Schumann, Matthew Thomas. "The effect of ion-orbit-loss on the distribution of ion, energy and momentum from the edge plasma into the scrape-off layer in tokamaks." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53519.

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Some of the outflowing ions in the plasma edge have sufficient energy to access orbits which allow them to free-stream out of the confined plasma region and be lost to the wall or divertor. The effects of this ion-orbit-loss (IOL) on the poloidal distribution of ion, energy and momentum fluxes from the plasma edge into the tokamak scrape-off layer (SOL) are analyzed for a representative DIII-D H-mode discharge. IOL yields large fluxes of particle, energy and momentum, distributed poloidally over the SOL, but predominantly into the outboard SOL, significantly changing the fluxes due to transport processes for confined ions within the edge plasma. An intrinsic co-current rotation in the edge of the plasma is produced by the preferential loss of counter-current ions
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45

Isildak, Ibrahim. "Ion selective electrodes in ion chromatography." Thesis, University of Newcastle Upon Tyne, 1992. http://hdl.handle.net/10443/859.

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The number of applications of potentiometric detection In Ion chromatography Is Increasing In the use of ion selective electrodes for which the response Is not limited to a few number of Ions. In this research, membrane electrodes, for a number of Ions, based on PVC were prepared to examine selectivity, detection limit and reproducibility for chromatographic and flow-injection measurements via mixed solution method and flow-injection technique. The selectivity sequence of anion selective electrodes for single charged Inorganic anions was F< Cl < Br < NO 2< NO 3
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46

Adelhelm, Philipp. "From Lithium-Ion to Sodium-Ion Batteries." Diffusion fundamentals 21 (2014) 5, S.1, 2014. https://ul.qucosa.de/id/qucosa%3A32397.

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47

Kjell, David. "ICD-patienters livskvalitet efter en ICD-implantation." Thesis, Malmö högskola, Fakulteten för hälsa och samhälle (HS), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-25577.

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En implanterbar defibrillator (ICD) är nuförtiden en väl beprövad behandlingsmetod för patienter som överlevt ett hjärtstopp eller har en avancerad hjärtsjukdom och därmed har ökad risk för ventrikulära arytmier. Syftet med vårt arbete var att beskriva ICD-patienters livskvalitet och de livsomställningar som en ICD-implantation medförde. Studien genomfördes som en litteraturöversikt enligt Willman et al. Resultat visade att livet med en ICD innebar omställningar och förändringar som många patienter inte var helt förberedda på. En defibrilleringschock visade sig inverka negativt på livskvaliteten. Professionell sjukvårdspersonal och anhöriga hade en viktig roll att spela vad gäller stöd, information och utbildning. Sjukvårdspersonal kan behöva ytterligare utbildning för att kunna ta hand om patienterna och möta dem i deras situation. Ytterligare forskning kan vara av värde för att se hur patienternas livskvalitet ser ut på längre sikt.
An implantable defibrillator is nowadays a well-known treatment for patients who survived a cardiac arrest or suffer from severe heart disease. The aim of our study was to describe ICD-patients quality of life and the life changes that come with the ICD-implantation. The study was conducted as a literature review pursuant to Willman et al. The result showed that patients living with an ICD needed to adapt to life changes that could occur. Defibrillation had a negative impact on quality of life. Medical staff and next of kin were important to provide support, information and education. All medical staff may need further education to properly manage the care of ICD-patients. Further research can be of value to evaluate patients’ quality of life in the long term.
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48

Mazon, Talita [UNESP]. "Preparação e caracterização de filmes finos de 'BA''BI IND.2''TA IND.2''O IND.9(BBT)' e 'BA''BI IND.2''NB IND.2''O IND.9(BBN)'." Universidade Estadual Paulista (UNESP), 2001. http://hdl.handle.net/11449/105671.

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Made available in DSpace on 2014-06-11T19:35:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2001Bitstream added on 2014-06-13T21:07:11Z : No. of bitstreams: 1 mazon_t_dr_araiq.pdf: 3325805 bytes, checksum: 1e16f8675a27d9c718c1eacce9a6a467 (MD5)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Nos últimos anos, filmes finos dos óxidos ferroelétricos de camadas de bismuto, também conhecidos como compostos pertencentes à família do Aurivillius, têm sido extensivamente estudados para aplicações em memórias ferroelétricas de acesso aleatório (FERAM). No entanto, muito pouco se sabe a respeito da preparação e propriedades dielétricas de filmes de BaBi2Ta2O9 (BBT) e BaBi2Nb2O9 (BBN), bem como a respeito da estrutura do BBT. Por isso, numa primeira etapa deste trabalho, pós de BBT foram preparados pelo método Pechini, para a determinação da estrutura. A formação de fases foi acompanhada por DRX. O pó calcinado a 800 oC por 2 horas e sinterizado a 850 oC por 4 horas apresentou 100% da fase BBT. A estrutura do BBT foi determinada pelo Método de Rietveld. Verificou-se que o BBT tem estrutura tetragonal com grupo espacial I4/mm, os cátions Ba e Bi compartilham ambos os sítios 2b e 4e. A fórmula (Ba0,70Bi0,30)(Bi1,64Ba0,36)Ta2O9 pode ser usada para escrever sua fórmula unitária. Numa segunda etapa, filmes finos de BBT e BBN foram preparados pelo método químico de Pechini. As soluções foram depositadas por “spin-coanting” em substratos de Pt/TiO2/SiO2/Si e rotacionados a 3000 rpm durante 30 segundos. Após a deposição os filmes foram tratados termicamente entre 600 e 800 oC sob atmosfera de oxigênio. Os filmes foram analisados por DRX, MEV, MFA, MET e propriedades elétricas. Os filmes preparados por este processamento apresentaram microestrutura heterogênea e piores propriedades dielétricas. Visando controlar a microestrutura e obter melhores propriedades dielétricas, foram feitas algumas modificações no processamento, tais como, adição de excesso de bismuto e adição de uma camada intermediária de tungstênio entre as camadas dos filmes de BBT ou BBN. Tanto a adição de excesso de bismuto como a utilização do dopante tungstênio...
In recent years the layered-structure perovskites, also known as Aurivillius compounds have attracted considerable attention for use in ferroelectric random access memories (FeRAM). However, there is little information available about the preparation and dielectric properties of BaBi2Ta2O9 (BBT) and BaBi2Nb2O9 (BBN) thin films, as well as, about the structure of BBT. Therefore, firstly BBT powders were prepared by Pechini method and the phase formation was verified by XRD. The powder calcined at 800 oC / 2 hours and sintered at 850 oC / 4h showed 100% of BBT phase. The structure of BBT was determined by the Rietveld method. BBT shows tetragonal structure (I4/mmm), and Ba and Bi share both the 2b and 4e sites. The (Ba0,70Bi0,30)(Bi1,64Ba0,36)Ta2O9 can be used to describe its unit formula. Secondly, thin films of BBT and BBN were prepared by Pechini method. They were deposited by spin coating over Pt/TiO2/SiO2/Si substrates followed by annealing under oxygen flux at different temperature. The thin films were analyzed by XRD, SEM, AFM, TEM and electric properties. The thin films showed heterogeneous microstructure and worst dielectric properties. Aiming to control the microstructure, it was done some modification during the process of preparation of BBT and BBN thin films. The use of Bi excess as well as the use of W6+ as dopant was favorable to control the microstructure and to obtain better dielectric properties. The best values to dielectric constant and dissipation factor were obtained for BBT thin films with addition of 5 wt% Bi excess heat annealed at 750 oC for 1 hour and BBN thin films with addition of 2 wt% Bi excess heat annealed at 700 oC for 1 hour The typical measured small signal dielectric constant and dissipation factor at 100 kHz were 210 and 0,025 for BBT and 356 and 0,023 for BBN, respectively...(Complete abstract click electronic access below)
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49

Mazon, Talita. "Preparação e caracterização de filmes finos de 'BA''BI IND.2''TA IND.2''O IND.9(BBT)' e 'BA''BI IND.2''NB IND.2''O IND.9(BBN)' /." Araraquara : [s.n.], 2001. http://hdl.handle.net/11449/105671.

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Orientador: Maria Aparecida Zaghete
Banca: Carlos de Oliveria Paiva-Santos
Banca: Sidney José Lima Ribeiro
Banca: Ducinei Garcia
Banca: Antonio Carlos Hernandes
Resumo: Nos últimos anos, filmes finos dos óxidos ferroelétricos de camadas de bismuto, também conhecidos como compostos pertencentes à família do Aurivillius, têm sido extensivamente estudados para aplicações em memórias ferroelétricas de acesso aleatório (FERAM). No entanto, muito pouco se sabe a respeito da preparação e propriedades dielétricas de filmes de BaBi2Ta2O9 (BBT) e BaBi2Nb2O9 (BBN), bem como a respeito da estrutura do BBT. Por isso, numa primeira etapa deste trabalho, pós de BBT foram preparados pelo método Pechini, para a determinação da estrutura. A formação de fases foi acompanhada por DRX. O pó calcinado a 800 oC por 2 horas e sinterizado a 850 oC por 4 horas apresentou 100% da fase BBT. A estrutura do BBT foi determinada pelo Método de Rietveld. Verificou-se que o BBT tem estrutura tetragonal com grupo espacial I4/mm, os cátions Ba e Bi compartilham ambos os sítios 2b e 4e. A fórmula (Ba0,70Bi0,30)(Bi1,64Ba0,36)Ta2O9 pode ser usada para escrever sua fórmula unitária. Numa segunda etapa, filmes finos de BBT e BBN foram preparados pelo método químico de Pechini. As soluções foram depositadas por "spin-coanting" em substratos de Pt/TiO2/SiO2/Si e rotacionados a 3000 rpm durante 30 segundos. Após a deposição os filmes foram tratados termicamente entre 600 e 800 oC sob atmosfera de oxigênio. Os filmes foram analisados por DRX, MEV, MFA, MET e propriedades elétricas. Os filmes preparados por este processamento apresentaram microestrutura heterogênea e piores propriedades dielétricas. Visando controlar a microestrutura e obter melhores propriedades dielétricas, foram feitas algumas modificações no processamento, tais como, adição de excesso de bismuto e adição de uma camada intermediária de tungstênio entre as camadas dos filmes de BBT ou BBN. Tanto a adição de excesso de bismuto como a utilização do dopante tungstênio...(Resumo Completo, clicar acesso eletrônico abaixo)
Abstract: In recent years the layered-structure perovskites, also known as Aurivillius compounds have attracted considerable attention for use in ferroelectric random access memories (FeRAM). However, there is little information available about the preparation and dielectric properties of BaBi2Ta2O9 (BBT) and BaBi2Nb2O9 (BBN) thin films, as well as, about the structure of BBT. Therefore, firstly BBT powders were prepared by Pechini method and the phase formation was verified by XRD. The powder calcined at 800 oC / 2 hours and sintered at 850 oC / 4h showed 100% of BBT phase. The structure of BBT was determined by the Rietveld method. BBT shows tetragonal structure (I4/mmm), and Ba and Bi share both the 2b and 4e sites. The (Ba0,70Bi0,30)(Bi1,64Ba0,36)Ta2O9 can be used to describe its unit formula. Secondly, thin films of BBT and BBN were prepared by Pechini method. They were deposited by spin coating over Pt/TiO2/SiO2/Si substrates followed by annealing under oxygen flux at different temperature. The thin films were analyzed by XRD, SEM, AFM, TEM and electric properties. The thin films showed heterogeneous microstructure and worst dielectric properties. Aiming to control the microstructure, it was done some modification during the process of preparation of BBT and BBN thin films. The use of Bi excess as well as the use of W6+ as dopant was favorable to control the microstructure and to obtain better dielectric properties. The best values to dielectric constant and dissipation factor were obtained for BBT thin films with addition of 5 wt% Bi excess heat annealed at 750 oC for 1 hour and BBN thin films with addition of 2 wt% Bi excess heat annealed at 700 oC for 1 hour The typical measured small signal dielectric constant and dissipation factor at 100 kHz were 210 and 0,025 for BBT and 356 and 0,023 for BBN, respectively...(Complete abstract click electronic access below)
Doutor
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50

Ebanezar, John Angelin [Verfasser]. "Negative Ion formation in Ion-Molecule and Ion-Surface collisions / Angelin Ebanezar John." Greifswald : Universitätsbibliothek Greifswald, 2014. http://d-nb.info/1061064654/34.

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