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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Konstruktion und funktionelle Charakterisierung löslicher Fragmente des Cytochrom c1 aus Paracoccus denitrificans

Eichhorn, Anna Carina. Unknown Date (has links)
Universiẗat, Diss., 2003--Frankfurt (Main).
2

Open Platform Semi-Passive Ultra High Frenquency Radio Frequency Identi

Li, Tzu Hao 20 June 2011 (has links)
Radio frequency identi cation (RFID) is a rapidly emerging technology that enables au- tomatic remote identi cation of objects. Passive and semi-passive RFID systems can be distinguished from other forms of wireless systems, because the RFID tags (transponders) communicate by way of backscatter. In addition, passive tags derive their energy from the RF energy emitted by the reader. RFID technology can provide a fully automated data capture and analysis system. Compared to a passive RFID system, an open platform semi-passive UHF RFID tag can provide identi cation, security, low-power (compared to a wireless sensor net- work(WSN)), medium range and medium processing speed. However, the eld of semi- passive RFID is still under development, and has yet there are no open development platforms available. This thesis develops a prototype of a semi-passive UHF RFID tag that is compatible with the leading UHF RFID standard EPCglobal Gen 2 Class 1. I alsot has the exible I2C and analog digital converter(ADC) interface, which allows the additional of external analog and digital sensors. The sensor data can be read by microcontroller and stored at memory. Standard reader can get sensor data by sending QUERY and READ command to tag. Test results of our open platform semi-passive UHF RFID tag demonstrated that it can achieve a read rate above 50% when an open platform semi-passive UHF RFID tag is placed four meters from the reader antenna and the reader output power is set to 21 dBm. In addition, the proposed semi-passive open platform RFID tag consumes very little power (4.9 mA in 2V with system frequency set to 8MHz).
3

Open Platform Semi-Passive Ultra High Frenquency Radio Frequency Identi

Li, Tzu Hao 20 June 2011 (has links)
Radio frequency identi cation (RFID) is a rapidly emerging technology that enables au- tomatic remote identi cation of objects. Passive and semi-passive RFID systems can be distinguished from other forms of wireless systems, because the RFID tags (transponders) communicate by way of backscatter. In addition, passive tags derive their energy from the RF energy emitted by the reader. RFID technology can provide a fully automated data capture and analysis system. Compared to a passive RFID system, an open platform semi-passive UHF RFID tag can provide identi cation, security, low-power (compared to a wireless sensor net- work(WSN)), medium range and medium processing speed. However, the eld of semi- passive RFID is still under development, and has yet there are no open development platforms available. This thesis develops a prototype of a semi-passive UHF RFID tag that is compatible with the leading UHF RFID standard EPCglobal Gen 2 Class 1. I alsot has the exible I2C and analog digital converter(ADC) interface, which allows the additional of external analog and digital sensors. The sensor data can be read by microcontroller and stored at memory. Standard reader can get sensor data by sending QUERY and READ command to tag. Test results of our open platform semi-passive UHF RFID tag demonstrated that it can achieve a read rate above 50% when an open platform semi-passive UHF RFID tag is placed four meters from the reader antenna and the reader output power is set to 21 dBm. In addition, the proposed semi-passive open platform RFID tag consumes very little power (4.9 mA in 2V with system frequency set to 8MHz).
4

Influence of growth and migration of human breast cancer cell by human C1 inhibitor N-terminus

Chen, Gen-yen 03 September 2010 (has links)
C1 inhibitor (C1 INH) is a member of the serine protease inhibitor (serpin) superfamily. It is the only physiological inhibitor of protease C1r and C1s in the complement system. C1 INH is a single chain glycoprotein with apparent molecular weight of 105 KDa, consisting of 478 amino acids. C1 INH N-terminal domain includes first 98 amino acids with 10 definite and 7 potential glycosylation site. Various of carbohydrates are present on the cell surface and component of ECM (extracellular matrix) in every eukaryotic cell, including both cancer cells and cells that are important for tumur survival. Carbohydrates on the cancer cell surface have been shown to be important in many aspects of cancer cell physiological processes, involved in cell growth and cell adhesion. Carbohydrates are also able to bind and interact with growth factors and other proteins that trigger signal transduction. Interfere carbohydrates maybe offer a useful therapeutic approach for treating cancers. In order to understand whether the C1 INH NT98 polypeptides can influences cancer or not, we amplified a DNA fragment encoding C1 INH N-terminal domain 98 residues (C1 INH NT98) by PCR, and transfer to the plasmid pGEX-2T, than use E.coli (BL21 strain) to express the non-glycosylated polypeptides, and further analyze the influence of the effective roles exhibited by the polypeptides non-glycosylated on breast cancer cell MDA-MB-435s. Proliferation and migration assays in our experiment showed that non-glycosylated C1 INH NT98 can inhibited breast cancer cell growth and migration, and the mechanism needed to be clarified clearly through extensive research.
5

Open Platform Semi-Passive Ultra High Frenquency Radio Frequency Identi

Li, Tzu Hao 20 June 2011 (has links)
Radio frequency identi cation (RFID) is a rapidly emerging technology that enables au- tomatic remote identi cation of objects. Passive and semi-passive RFID systems can be distinguished from other forms of wireless systems, because the RFID tags (transponders) communicate by way of backscatter. In addition, passive tags derive their energy from the RF energy emitted by the reader. RFID technology can provide a fully automated data capture and analysis system. Compared to a passive RFID system, an open platform semi-passive UHF RFID tag can provide identi cation, security, low-power (compared to a wireless sensor net- work(WSN)), medium range and medium processing speed. However, the eld of semi- passive RFID is still under development, and has yet there are no open development platforms available. This thesis develops a prototype of a semi-passive UHF RFID tag that is compatible with the leading UHF RFID standard EPCglobal Gen 2 Class 1. I alsot has the exible I2C and analog digital converter(ADC) interface, which allows the additional of external analog and digital sensors. The sensor data can be read by microcontroller and stored at memory. Standard reader can get sensor data by sending QUERY and READ command to tag. Test results of our open platform semi-passive UHF RFID tag demonstrated that it can achieve a read rate above 50% when an open platform semi-passive UHF RFID tag is placed four meters from the reader antenna and the reader output power is set to 21 dBm. In addition, the proposed semi-passive open platform RFID tag consumes very little power (4.9 mA in 2V with system frequency set to 8MHz).
6

Open Platform Semi-Passive Ultra High Frenquency Radio Frequency Identi

Li, Tzu Hao January 2011 (has links)
Radio frequency identi cation (RFID) is a rapidly emerging technology that enables au- tomatic remote identi cation of objects. Passive and semi-passive RFID systems can be distinguished from other forms of wireless systems, because the RFID tags (transponders) communicate by way of backscatter. In addition, passive tags derive their energy from the RF energy emitted by the reader. RFID technology can provide a fully automated data capture and analysis system. Compared to a passive RFID system, an open platform semi-passive UHF RFID tag can provide identi cation, security, low-power (compared to a wireless sensor net- work(WSN)), medium range and medium processing speed. However, the eld of semi- passive RFID is still under development, and has yet there are no open development platforms available. This thesis develops a prototype of a semi-passive UHF RFID tag that is compatible with the leading UHF RFID standard EPCglobal Gen 2 Class 1. I alsot has the exible I2C and analog digital converter(ADC) interface, which allows the additional of external analog and digital sensors. The sensor data can be read by microcontroller and stored at memory. Standard reader can get sensor data by sending QUERY and READ command to tag. Test results of our open platform semi-passive UHF RFID tag demonstrated that it can achieve a read rate above 50% when an open platform semi-passive UHF RFID tag is placed four meters from the reader antenna and the reader output power is set to 21 dBm. In addition, the proposed semi-passive open platform RFID tag consumes very little power (4.9 mA in 2V with system frequency set to 8MHz).
7

Studies on distribution and colonization of facultative methylotrophic bacteria Methylobacterium spp. on the perilla plant / 通性メチロトロフ細菌Methylobacterium spp.のシソ上での分布と定着能に関する研究

Mizuno, Masayuki 23 May 2013 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第17792号 / 農博第2013号 / 新制||農||1016(附属図書館) / 学位論文||H25||N4783(農学部図書室) / 30599 / 京都大学大学院農学研究科応用生命科学専攻 / (主査)教授 阪井 康能, 教授 小川 順, 教授 梅澤 俊明 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
8

Neurônios catecolaminérgicos do tronco encefálico participam dos ajustes respiratórios induzidos por hipóxia e hipercapnia. / Catecholaminergic neurons of the brainstem contributes to respiratory adjusts induced by hypoxia and hypercapnia.

Lima, Milene Rodrigues Malheiros 25 August 2017 (has links)
Os neurônios do grupamento catecolaminérgico C1, localizados na porção ventrolateral do bulbo, são classicamente conhecidos por seu envolvimento no controle cardiovascular. O modelo atual propõe que os neurônios C1 são recrutados em situações que ofereçam risco de vida aos indivíduos, desencadeando respostas generalizadas e estereotipadas em defesa da homeostase. Tais respostas envolvem ajustes cardiovasculares, imunológicos, neuroendócrinos, metabólicos, termorregulatórios e respiratórios. Ferramentas anatômicas e funcionais foram utilizadas para investigar se os neurônios C1 contribuem para os ajustes respiratórios induzidos pela hipóxia e pela hipercpania. Os resultados mostram que os neurônios C1 contribuem para a aumento da ventilação induzido pela hipóxia, mas não pela hiperpania, via aumento da frequência da respiratória. Além disso, demonstramos que o aumento da frequência respiratória promovido pela ativação do grupamento C1 depende da ativação de receptores glutamatérgicos, mas não adrenérgicos, localizados na região do complexo pré-Bötzinger. / The catecholaminergic C1 neurons, located in the rostral ventrolateral portion of the medulla, are classically known by their involvement in the cardiovascular control. Recent models suggest that C1 neurons are recruited in situations of life risk, triggering generalized and stereotyped responses to homeostasis. Such responses involve cardiovascular, immunologic, neuroendocrine, metabolic, thermoregulatory and respiratory adjustments. Thus, anatomic and functional tools were used to assess the contribution of C1 neurons to the respiratory adjustments induced by hypoxia and hypercapnia. The results show that these neurons contribute to the increase of ventilation induced by hypoxia, but not by hypercapnia, via an increase of the breathing frequency. Moreover, we demonstrated that increase of breathing frequency promoted by the activation of C1 neurons depend on the activation of glutamatergic receptors, but not adrenergic, located in the pre-Bötzinge complex.
9

Arthrobacter globiformis glicino betaino katabolizmo genų tyrimas / Analysis of genes encoding glycine betaine catabolism in arthrobacter globiformis

Bružytė, Simona 08 September 2009 (has links)
Arthrobacter sp. yra dirvoje paplitusios bakterijos, kurios gali prisitaikyti prie nepalankių aplinkos sąlygų, tokių kaip osmosinis šokas ar maisto medžiagų trūkumas. Osmoreguliacijoje daugelis organizmų naudoja glicino betainą. Yra žinoma, kad Arthrobacter globiformis bakterijos gali panaudoti glicino betainą kaip anglies ir azoto šaltinį, tačiau nebuvo aišku, ar Arthrobacter globiformis gali šią medžiagą naudoti kaip osmoprotektorių. Iš Arthrobacter globiformis buvo klonuotas DNR fragmentas, kuriame buvo identifikuoti genai, kurie tiesiogiai ir netiesiogiai dalyvauja glicino betaino katabolizme. Struktūrinė genų organizacija leidžia manyti, kad šios bakterijos gali panaudoti glicino betainą kaip osmoprotektorių, Taip pat buvo įdomu patikrinti, ar tokią funkciją glicino betainas gali vykdyti ir kitose A. globiformis giminingose bakterijose. Tyrimui buvo pasirinkti tipiniai Arthrobacter genties bakterijų kamienai (A. atrocyaneus, A. citreus, A. crystalopoietes, A. globiformis, A. ramosus, A. sulfureus bei Arthrobacter spp. (KA3, P3, KA2V2, PY22, KA2, GAZ21, P2G, KA4, KA2V3, GAZ3, PRH1, PY21, VM22, VP23, RD1, VM22, VP22, VP3, VPW7, VPS4, 96, 94, 85, 68M, 83 68B, BL-3 ir 1-IN). Darbo metu paaiškėjo, kad šį junginį apsaugai nuo osmosinio streso naudoja tik dalis Arthrobacter genties bakterijų. Glicino betainas artrobakterėse dažniau naudojamas kaip anglies šaltinis. / Arthrobacter spp. are wide-spread soil bacteria, which are adapted to grow under osmotic stress and shortage in available carbon (energy) sources. Many organisms utilise glycine betaine as an osmoprotectant. It is known, that Arthrobacter globiformis can use glycine betaine as a sole carbon and nitrogen source, however, it is unclear whether this bacterium use this substrate as osmoprotectant. A DNA fragment harbouring genes, which directly and indirectly are involved in glycine betaine degradation, was cloned from A. globiformis. The structural organization of these genes suggested, that this bacterium could use glycine betaine as an osmoprotectant. So, it was tested if other Arthrobacter spp. strains use glycine betaine to protect from osmotic stress. Typical Arthrobacter sp. strains (A. atrocyaneus, A. citreus, A. crystalopoietes, A. globiformis, A. ramosus, A. sulfureus and Arthrobacter spp. (KA3, P3, KA2V2, PY22, KA2, GAZ21, P2G, KA4, KA2V3, GAZ3, PRH1, PY21, VM22, VP23, RD1, VM22, VP22, VP3, VPW7, VPS4, 96, 94, 85, 68M, 83 68B, BL-3 and 1-IN) were chosen in this study. It turned out, that less than a half of studied strains use glycine betaine as osmoprotectant. The arthrobacters used glycine betaine more as a sole carbon source than as an osmoprotectant.
10

Réactions d’interconversion catalytiques entre composés C1 : CO2, CO, acide formique, méthanol, méthane et dérivés / Catalytic interconversion reactions between C1 compounds : CO2, CO, formic acid, methanol, methane and derivatives

Imberdis, Arnaud 30 September 2019 (has links)
Notre société s’est considérablement développée grâce à l’utilisation des ressources fossiles. L’utilisation de ces ressources, dans le domaine de l’énergie ou de l’industrie chimique, provoque un dérèglement du cycle naturel du carbone par l’accumulation dans l’atmosphère d’un CO2 anthropogénique. Pour pallier ces difficultés, une des solutions envisagées consiste à abandonner progressivement les hydrocarbures fossiles au profit de ressources carbonées renouvelables telles que le CO₂ pour le stockage des énergies renouvelables et/ou comme sources de produits chimiques. Les premières briques obtenues grâce au CO2 sont des molécules comportant un seul atome de carbone, rassemblées dans la classe de composés C1. Elle comprend le méthane (CH4), le monoxyde de carbone (CO), le méthanol (CH3OH), l’acide formique (HCOOH). Ces réactions ne sont pas idéales, limitées par leur praticité, leur rendement ou par leur sélectivité. Dans ce contexte, le présent travail doctoral a exploré des chemins alternatifs permettant d’interconvertir ces composés pour offrir des voies de valorisation du CO2. En premier lieu, l’utilisation de HCOOH sera proposé comme vecteur de CO. Cette thématique est née de l’intérêt grandissant pour le secteur de la chimie organique d’obtenir des sources liquides ou solides de CO. Dans un second temps, il a été développé une nouvelle stratégie de dismutation pour accéder au CH3OH à partir de dérivés de HCOOH, les formiates de silicium. Ces réactifs permettent de s’affranchir de la limitation thermodynamique dont souffre la dismutation de HCOOH. Cette transformation a été assurée en maîtrisant le recyclage des coproduits silylés. Une nouvelle voie de production de CH4 a également été développée à partir du CH3OH, en utilisant HCOOH comme réducteur. Enfin, les connaissances acquises sur l’activiation et la réactivité du CO2 ont permis, par analogie, de transposer ces connaissances à l’étude d’autres molécules iso-électroniques, telles que les carbodiimides et leur transformation en isourées dans des conditions organocatalytiques. / Our society has grown considerably thanks to the use of fossil resources. The use of these resources, in the field of energy or the chemical industry, leads to a disruption of the natural carbon cycle caused by the accumulation of an anthropogenic CO2 in the atmosphere. To overcome this issue, one of the conceivable solutions is to gradually abandon fossil hydrocarbons in favor of renewable carbon resources such as CO₂ for the storage of renewable energies and / or as a source of chemical products. The first building blocks obtained from CO2 are one carbon atom containing molecules, known as C1 compounds. It includes methane (CH4), carbon monoxide (CO), methanol (CH3OH), formic acid (HCOOH). These reactions are limited by their practicality, their yield or by their selectivity. Therefore, they are not an ideal solution to the initial problem. In this context, this doctoral work has explored alternative ways of interconverting these compounds to offer CO2 recovery pathways. In the first place, the use of HCOOH was proposed as a CO vector. This topic is born of the growing interest for the organic chemistry sector to obtain liquid or solid sources of CO. In a second step, a new disproportionation strategy was developed to access CH3OH from HCOOH derivatives, the silicon formates. These reagents allow to avoid the thermodynamic limitation related to the disproportionation of HCOOH. The control of the silylated by-products recycling enabled the success of this transformation. A new CH4 production route was also developed from CH3OH using HCOOH as a reducing agent. Finally, the knowledge acquired on CO2 activation and reactivity enabled a transposition by analogy to other iso-electronic molecules, including carbodiimides in order to form the isoureas under organocatalytic conditions.

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