Master of Science / Department of Electrical and Computer Engineering / William B. Kuhn / RF frequency synthesizer systems are prevalent in today’s electronics. In a synthesizer there is a sensitive analog oscillator that may be affected by two different types of noise. The first is random noise injection from active devices. This results in phase noise in the synthesizer’s spectrum. The second noise source is deterministic. A digital frequency divider with high-amplitude switching is an example of such a deterministic source. This noise enters the system through various forms of electric or magnetic field coupling and manifests itself as spurs or pulling. Both forms of noise can adversely affect system performance. We will first summarize methods for reducing noise. These already known steps have to do with layout techniques, device geometry, and general synthesizer topologies. Then we will show ways to isolate noisy interfering circuits from the sensitive analog systems. Finally, we present some considerations for reducing the effects of random noise. A power supply filter can improve the effects of deterministic noise such as undesired signals on the supply line. We show several ways to improve the rejection of high frequency supply noise (characterized by the power supply rejection ratio or PSRR) through the design of a voltage regulator. The emphasis is on new techniques for obtaining good PSRR at S-band frequencies and above. To validate the techniques, we designed a regulator in Peregrine Semiconductor’s .25µm ULTRA CMOS Silicon on Sapphire process. It produces a 2.5V output with an input ranging from 2.6V to 5V and has a maximum current sourcing of 70mA. The regulator’s low drop out performance is 60mV with no load and it achieves a power supply ripple reduction of 29.8 dB at 500 MHz. To address random noise in synthesizers, the thesis provides preliminary investigation of an oscillator topology change that has been proposed in the literature. This proposed change reduces the phase noise of the oscillator within the overall system. A differential cross-coupled design is the usual topology of choice, but it is not optimal for noise performance. We investigate current noise injection in the traditional design and present an updated design that uses a differential Colpitts oscillator as an alternative to classic cross-coupled designs.

Prostate cancer (PC) is characterised by dependence upon androgen receptor (AR) as its driving oncogene. When organ-confined, radical treatment can be curative, however there is no cure for advanced, castration-resistant prostate cancer (CRPC). There is therefore a need to better understand the biology of PC, and how influencing AR can modify disease progression. Estrogen is essential for prostate carcinogenesis with evidence from epidemiological, in vitro, human tissue and animal studies. Most suggests that estrogen receptor beta (ERβ) is tumour-suppressive, but trials of ERβ-selective agents have not improved clinical outcomes. ERβ has also been implicated as an oncogene, therefore its role remains unclear. Additional evidence suggests interplay between ERβ and AR, the mechanisms of which are uncertain. The study hypothesis ‘ERβ is an important modulator of prostate carcinogenesis’ was developed to establish whether targeting ERβ could affect PC progression. Much of the confusion around ERβ stems from use of inadequately validated antibodies and cell line models. The first phase of this work was to test ERβ antibodies using an ERβ-inducible cell system. Eight ERβ antibodies were assessed by multiple techniques, showing that commonly used antibodies are either non-specific or only specific in one modality. Two reliable antibodies were identified. Next, cell lines previously used to study ERβ were assessed using validated antibodies and independent approaches. No ERβ expression was detected; an important finding that casts doubt on previously published ERβ biology. Subsequently, a PC cell line with inducible ERβ expression (LNCaP-ERβ) was developed and validated to enable controlled experiments on the effects of ERβ on proliferation, gene expression and ERβ/AR genomic cross-talk. Phase three of this work focused on ERβ biology in PC and its relationship to AR. Interrogation of clinical datasets showed that greater ERβ expression associated with favourable prognosis. Gene expression data from men treated with androgen deprivation therapy revealed that AR represses ERβ. This was confirmed in vitro. The LNCaP-ERβ cell line was treated with androgen and/or ERβ-selective estrogen. Activated ERβ in the presence of androgen-stimulated AR inhibited cell proliferation and down-regulated androgen-dependent genes. Genome-wide mapping of ERβ binding sites reveals that ERβ antagonises AR through competition for shared DNA binding sites. In conclusion, ERβ expression is down-regulated by AR during malignant transformation of prostate epithelium. We reveal an antagonistic relationship between ERβ and AR whereby sustaining or replacing ERβ may inhibit tumour growth through down-regulation of AR-target genes. In future, an ERβ-selective compound may be used to slow or abrogate PC progression.

La polarité cellulaire est une caractéristique commune à tous les organismes. Jusqu’à récemment, il était assumé que la sécrétion de protéines vers des domaines polaires de la cellule végétale se faisait de façon non polarisée, mais ce point de vue a été re-étudié, la sécrétion est polarisée mais la dynamique, les voies de traficempruntées et les mécanismes sont toujours inconnus. Précédemment, mon laboratoire d’accueil a caractérisé un enrichissement en sphingolipides contenant des acides gras à très longues chaines (VLCFAs) au niveau d’un sous-domaine du trans-Golgi Network (TGN) appelé Vésicules de Sécrétions (SVs). Plus précisément, il a été montré que la longueur des acides gras des sphingolipides jouait un rôle critique dans la sécrétion du transporteur d’auxine PIN2 des SVs vers des domaines polaires de la membrane plasmique. Pendant ma thèse, je me suis intéressé à la question suivante : comment les sphingolipides agissent-t-ils au TGN? En identifiant le protéome des SVs, ainsi qu'en utilisant des outils génétiques et pharmacologiques en combinaison avec la visualisation de marqueurs lipidiques, j'ai pu identifier que les sphingolipides agissent sur l’homéostasie des phosphoinositides en mettant en avant un lien fonctionnel entre ces deux classes de lipides au sein de la cellule végétale. En utilisant un set de marqueurs des phosphoinositides (PIPs), j’ai pu montrer que les sphingolipides ciblent principalement le phosphatidyl-inositol-3-phosphate, PI(3)P et le phosphatidylinositol- 4-phosphate, PI(4)P. De plus, mon analyse protéomique a montré que la localisation d'un ensemble de protéines liées aux PIPs était diminuée dans les SVs/TGN immunopurifiées quand la composition des sphingolipides est altérée. Mes résultats nous forcent à revoir notre vision de la dynamique des lipides au niveau des membranes, et suggère l’idée que la dynamique de remodelage de la composition d’une classe de lipide, les phosphoinositides, peut être modulée par une autre classe de lipide, les sphingolipides. / Cell polarity is a defining feature of all organisms. Until very recently, it was thought that delivery of proteins to polar domains of root epidermal cells plasma membrane was non-polar, but this view has been re-examined, the delivery is polar but the dynamics, the paths taken, and the mechanisms are unknown. My host team previously characterised an enrichment of Very-Long-Chain-Fatty-Acids (VLCFAs)-containing sphingolipids at the site of secretory vesicles (SVs) sub-domain of the trans-Golgi Network (TGN). Moreover, the length of sphingolipids acyl-chain was found to play a critical role in secretory sorting of the auxin carrier PIN2 from SVsassociated TGN to apical polar domain of the plasma membrane (PM). During my PhD, I addressed the following question: how sphingolipids act at SVs/TGN? Using proteomics of SVs, genetics and pharmacological tools in combination with visualisation of lipid probes we could identify that sphingolipids act on phosphoinositides (PIPs) homeostasis establishing a new functional link between these two lipids in plant cells. Using a set of multi-affinity fluorescent PIPs probes I could show that sphingolipids target phosphatidylinositol-3-phosphate (PI3P) and phosphatidylinositol-4-phosphate (PI4P). Moreover, my proteomic analyses show that several PIPs-related proteins are downregulated in immuno-purified TGN-associated SVs when the sphingolipid composition is altered pharmacologically. My results force the reassessment of our view of lipid membranes dynamics and highlight the idea that dynamic remodelling of the composition of one lipid class, the phosphoinositides, can be modulated by another lipid class, the sphingolipids.

Previously it has been shown that Rsp5p, a member of Nedd4 ubiquitin ligases in yeast, is modified by the ubiquitin-like protein SUMO and that this modification is performed by Siz1p, a member of PIAS SUMO ligases that are in turn substrates of Rsp5p-dependent ubiquitylation, thus defining a previously unidentified system of crosstalk between the ubiquitin and SUMO systems in yeast. This project aims to identify whether similar crosstalk pattern exists in human cells. In vitro ubiquitylation assays showed that some of the human Nedd4 family members (Nedd4.1, Nedd4.2, WWP1) are capable of ubiquitylating the human SUMO ligase PIAS3, while in contrast, Smurf2 does not appear to be able to modify this protein. This modification is partially WW-PY-motif-dependent as ubiquitylation level of PIAS3 mutants with altered PY motifs conducted by Nedd4.1 or Nedd4.2 was reduced, but not completely disrupted. Interestingly, in vitro SUMOylation assay revealed that Nedd4.1 is SUMOylated even in the absence of SUMO E3 ligases and an apparent interaction between the SUMO E2 (Ubc9) and Nedd4.1 was observed both in vitro and in vivo. I show that auto- SUMOylation of Nedd4.1 is accompanied with the formation of thioester-linked conjugates between Nedd4.1 and SUMO, but these do not involve cysteine residues (C867, C778, and C627) within the HECT domain itself and is not occurring at a predicted SUMOylation consensus site (K357). Furthermore, I have shown that Nedd4.1 and SUMO1/2 colocalize in HeLa cells, and that overexpression of epitope tagged Nedd4 and SUMO1/2, followed by denaturing pull-downs demonstrates that both Nedd4.1 and Nedd4.2 can be SUMOylated in vivo. Meanwhile, I have generated a SUMO trap based on SUMO interacting motifs (SIMs) and confirmed its ability of capturing SUMOylated proteins both in vivo and in vitro. Its use reveals that Nedd4 SUMO conjugates could be captured by SUMO trap when Nedd4 and SUMO were co-expressed in HeLa cells, again confirming Nedd4.1 as a substrate for SUMO1 or SUMO2. In conclusion, I show that SUMOylation of Nedd4.1 does exist in HeLa cells, and on the other hand, some of Nedd4 family members are responsible for PIAS3 ubiquitylation in vitro, providing evidence of a crosstalk between Nedd4 family of ubiquitin ligases and PIAS family of SUMO ligases in mammals.

<p>This master's thesis deals with timing effects in complex on chip systems. It is written in cooperation with the research and development centre of Infineon Technologies. </p><p>One primary goal of all integrated circuit designers is to make the chips as small as possible. In deep sub micron designs timing effects like crosstalk have severe impact on the functionality of the chip. Therefore, accurate timing analyses must be made before the chip is ready for manufacturing. Otherwise the production yield can be reduced drastically. A case study on timing analysis with the 0.13 µm technology is made on the bus system of the device S-GOLD. </p><p>The computer-based program PrimeTime is used to carry out the timing analysis. During the evolution of 0.13 µm technology three design packages have been developed to characterize the timing. Two releases of SGOLD have been designed based on the first and the second design package. The different design packages were compared, with and without pin capacitance variations, on chip variations and crosstalk. Furthermore the two releases are compared. The result from the analysis tool may not correlate well with what you see on the manufactured chips. In order to investigate the correlation, some tests were finally performed on an evaluation board. </p><p>The results from the timing analysis are as expected. The second netlist version is better optimized than the first one. Design package three is most pessimistic among the three design packages. Design package one is most optimistic and does not match the real performance. Both design package two and three fit to the real performance well. Among the three design packages, design package three fits the real performance best.</p>

<p>This report is the result of a Master Thesis work that has been performed between October 2003 and March 2004. The purpose of the work was to evaluate a part of the signal chain in a product of Micronic Laser Systems AB. The evaluation was performed to obtain the characterisation for the signal chain, such as impedances and crosstalk. </p><p>The work started with a literature study in order to refresh and increase the knowledge that was needed before the practical work. Then measurements, computer aided simulations and comparisons between these were performed. </p><p>Measurements were performed using TDR (Time Domain Reflectometry). The results showed the impedance levels along the signal chain. This was interesting since it showed how well the different parts in the system are matched. Unmatched parts result in reflections that disturb the transmitted signal and contribute to crosstalk, which also was measured. </p><p>Simulations were done using ADS (Advance Design System), a tool from Agilent Technologies Inc. A substantial part of the simulation work was to build models of the real system. These models have been used for simulation. The simulation results were then compared to the measurement results. </p><p>The results show that the system can be better matched concerning the channel impedance. There are large variations in impedance levels along the signal chain, resulting in signal reflections. Another effect studied is crosstalk between channels. Measurements and simulations showed the presence of crosstalk but it seems to be a minor problem in the current machine.</p>

<p>This thesis work investigates the effects of crosstalk on on-chip interconnects. We use optimal repeater insertion as a reference and derive analytical expressions for signal latency, maximum data-rate and power consumption. Through calculations and simulations we show that despite large uncertainties in arrival time of a signal that is subject to crosstalk, we are able to make predictions about the maximum data-rate on a bus. We also show that data-rates can exceed the classical limit of the latency inverted by using wave pipelining. To increase the data-rate, we can increase the number of repeaters to a limit, at the cost of additional latency and power. Savings in power consumption can be achieved by using fewer repeaters, paying in latency and data-rate. Through fewer repeaters, the top metal layer shows better performance in all investigated aspects.</p>

This master's thesis deals with timing effects in complex on chip systems. It is written in cooperation with the research and development centre of Infineon Technologies. One primary goal of all integrated circuit designers is to make the chips as small as possible. In deep sub micron designs timing effects like crosstalk have severe impact on the functionality of the chip. Therefore, accurate timing analyses must be made before the chip is ready for manufacturing. Otherwise the production yield can be reduced drastically. A case study on timing analysis with the 0.13 µm technology is made on the bus system of the device S-GOLD. The computer-based program PrimeTime is used to carry out the timing analysis. During the evolution of 0.13 µm technology three design packages have been developed to characterize the timing. Two releases of SGOLD have been designed based on the first and the second design package. The different design packages were compared, with and without pin capacitance variations, on chip variations and crosstalk. Furthermore the two releases are compared. The result from the analysis tool may not correlate well with what you see on the manufactured chips. In order to investigate the correlation, some tests were finally performed on an evaluation board. The results from the timing analysis are as expected. The second netlist version is better optimized than the first one. Design package three is most pessimistic among the three design packages. Design package one is most optimistic and does not match the real performance. Both design package two and three fit to the real performance well. Among the three design packages, design package three fits the real performance best.

This report is the result of a Master Thesis work that has been performed between October 2003 and March 2004. The purpose of the work was to evaluate a part of the signal chain in a product of Micronic Laser Systems AB. The evaluation was performed to obtain the characterisation for the signal chain, such as impedances and crosstalk. The work started with a literature study in order to refresh and increase the knowledge that was needed before the practical work. Then measurements, computer aided simulations and comparisons between these were performed. Measurements were performed using TDR (Time Domain Reflectometry). The results showed the impedance levels along the signal chain. This was interesting since it showed how well the different parts in the system are matched. Unmatched parts result in reflections that disturb the transmitted signal and contribute to crosstalk, which also was measured. Simulations were done using ADS (Advance Design System), a tool from Agilent Technologies Inc. A substantial part of the simulation work was to build models of the real system. These models have been used for simulation. The simulation results were then compared to the measurement results. The results show that the system can be better matched concerning the channel impedance. There are large variations in impedance levels along the signal chain, resulting in signal reflections. Another effect studied is crosstalk between channels. Measurements and simulations showed the presence of crosstalk but it seems to be a minor problem in the current machine.

This thesis work investigates the effects of crosstalk on on-chip interconnects. We use optimal repeater insertion as a reference and derive analytical expressions for signal latency, maximum data-rate and power consumption. Through calculations and simulations we show that despite large uncertainties in arrival time of a signal that is subject to crosstalk, we are able to make predictions about the maximum data-rate on a bus. We also show that data-rates can exceed the classical limit of the latency inverted by using wave pipelining. To increase the data-rate, we can increase the number of repeaters to a limit, at the cost of additional latency and power. Savings in power consumption can be achieved by using fewer repeaters, paying in latency and data-rate. Through fewer repeaters, the top metal layer shows better performance in all investigated aspects.