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Choice in the Age of Opinion How Opinion Voicing Reconfigures the Psychological Meaning of Choosing
No full textThe aim of this thesis is to study how opinion voicing can affect choice at a basic psychological level. Seven experiments lend empirical support to the premise that opinion voicing reconfigures the psychological meaning of choice through two different ways. First, it was argued that the availability of opinion voicing opportunities can undermine choice self-expressiveness and hence reduce post-choice rationalization. Second, it was suggested that the subjective construal of opinionation can reduce preference-choice consistency. As a whole, the overarching idea informing all studies is that opinion voicing reconfigures the psychological function of choice, as studied through well-established effects associated with the relation between preferences and choices through an experimental social psychological perspective. Unlike prior research that has largely focused on the interpersonal influence of expressed opinions on others’ choices, this research proposes an intrapersonal approach. Insofar as opinion and choice are parts of the self-concept, one’s opinions can interact with one’s own choices. In view of groundbreaking technological developments and societal changes that render opinion voicing at once all the more accessible and all the more valued, this research highlights how the proliferation of opportunities to express ourselves through opinions might change the way we relate to our choices, and how different construals of opinion voicing might also affect the extent to which we are driven by our preferences when choosing
A proteome wide approach to understand chromatography behavior on hydrophobic adsorbents
No full textThe separation behavior of the Saccharomyces cerevisiae cell proteome was explored by hydrophobic interaction chromatography (HIC). Several beaded adsorbents were studied. A first group of HIC adsorbents (n = 3) harbored the same ligand moiety (i.e., Phenyl) but presented differences in the chemical nature of the matrix backbone. On the other hand, a second group of adsorbents (n = 3) presented the same chemical structure (i.e. based on polymethacrylate; Toyopearl / TP) but differed in the chemical nature of the HIC ligands. Chromatography runs were performed under typical conditions employing ammonium sulfate / phosphate buffer (pH = 7.5) as a mobile phase. Chromatography fractions were collected and further analyzed by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE); selected spots were identified by MALDI-ToF-MS and database search. A comparative analysis of protein separation behavior is presented as a function of the adsorbent type. As expected, TP-Hexyl and TP-Butyl showed increased protein retention in comparison with TP-Ether. Moreover, an influence of protein size and isoelectric point (pI) was also revealed. Larger and / or neutral proteins showed increased while acidic (pI 8) proteins depicted decreased or increased retention, depending on the adsorbent-type. Protein characteristics such as average surface hydrophobicity, average hydrophobicity average polarity, average bulkiness and average flexibility were tabulated for the identified spots and correlated with chromatography behavior. The proteins properties revealed limited ability to differentiate among the ligands and base supports for their hydrophobicity. This work -for the first time- studied the separation behavior of a real and complex cell proteome as a function of commercially available HIC adsorbents. The mentioned results will favor the understanding and the application of HIC, a method of choice in many industrial bio-separation schemes
Decoupling Mesh and Data Representations for Geo-spatial Data Visualization
No full textNowadays, data visualization plays an important role in geo-spatial data investigations, speci cally in the context of visual exploration at interactive frame rates. Geo-spatial data typically include geographic information in form of a set of gridded or un-gridded points, where each point identies a location on the earth's surface. A variety of projection methods are in use to re-produce the location of a speci c data point. For example, in contrast to the longitude/latitude projection system, the UTM (Universal Transverse Mercator) system provides a conformal projected location of the earth based on a non-linear scaling in both easting and northing. In this work, geo-spatial data such as terrain or ocean oor data are represented as 2D coordinates, e.g., longitude/latitude, and a number of associated attributes of measured information such as depth or height, backscattering, sub-bottom pro le information, etc. Both main and graphical memory capacities are steadily increasing, but so are data sizes. Hence, current and future storage capacities still lack the ability to handle the targeted enormous data sizes with proper efficiency. To allow for interactive exploration, the number of rendered objects in most dynamic approaches is obligated to be below a certain complexity at run time. Ful lling such goals requires several techniques to be integrated in our data exploration approach. View-dependency, LOD (level of detail) representations, and multi-resolution methods form the basis to tackle the objects redundancy, dynamic data updates, and simplification. Existing approaches can be classi ed into two main groups, the ones that operate on irregular triangular meshes and the ones that operate on regular grids. While irregular triangular meshes can provide better adaptivity, regular grids can be handled more effciently. Our approach is to decouple mesh and data representations such that data management is performed effciently on regular grids while mesh rendering is executed using a fixed adaptive triangular mesh in parameter plane. The triangular mesh is optimized with respect to the projected triangle sizes and shapes. During interaction we update the mesh by merely adjusting the vertices' heights, which are queried from an underlying multi-resolution grid structure. The triangular mesh and the multi-resolution grid structure are precomputed and cached on the GPU. A tiling strategy is employed for the grid structure. We are able to generate very high frame rates using triangles with optimized shape in a high-quality rendering. Our approach is applied to di erent data types as inputs such as terrain data and bathymetry data. Terrain data include heightfield and color information that is acquired using aerial instruments. From the given data, hierarchies are generated in a pre-processing step. Bathymetry data are acquired using multibeam sonar. The measured data include information on the structure and nature of the ocean floor and gas maps underneath the ocean surface. Data exploration, ocean floor rendering, and further data visualization methods are employed in an interactive system. Our work provides highperformance algorithms and evaluates them utilizing synthetic as well as real data from both terrain and bathymetry measurements. Our contribution in the terrain or ocean floor rendering field is providing a new and fast method for height eld exploration and rendering with frame rates exceeding those of most state-of-the-art approaches while providing optimal triangle shapes. In particular, using a fixed mesh, some interactive operations do not require data updates. Moreover, the interactive visual system comprises visualization of backscatter and water column data incorporated in the final rendering scene, which is a novel visualization task that has not yet been tackled by the existing 3D visualization systems for bathymetry data such as Fledermaus
Particulate organic matter fluxes and carbon cycling at cold-water coral reefs A three years study at the Tisler Reef, Norway
No full textCold-water corals (CWC) occur throughout the world’s oceans, with the reef building coral Lophelia pertusa forming giant reefs and mounds in the Northeast Atlantic. Several important issues regarding CWC reefs remain not well understood. These include the relative contribution of different food sources to CWC ecosystem nutrition, the influence of hydrodynamic processes on reef nutrition, as well as the contribution of CWC ecosystems to benthic carbon turnover along continental margins. Within this PhD project, these issues were addressed at the Tisler cold-water coral reef (Norway) in a succession of field campaigns between 2007 and 2009, using a variety of methodological approaches. These consisted, amongst others, of the collection of CTD and chlorophyll profiles, the sampling and analyses of particulate organic matter (POM), the deployment of sediment traps, as well as the deployment of current meters, temperature sensors and oxygen sensors for time-series measurements. The environmental conditions at the Tisler Reef were found to be highly dynamic in terms of temperature and flow. Downwelling periodically delivered warmer, fresher and chlorophyll richer water masses down to the benthic boundary layer (BBL) of the downstream reef side. Particulate organic carbon (POC) content in the BBL was significantly depleted across the reef. Biodeposition was calculated to be 459 mg POC m-2 d-1 on average. Dissolved oxygen concentration within the reef structure decreased rapidly during short phases of stagnant or near stagnant flow. A community respiration rate of 981 mg C m-2 d-1 was estimated. Vertical POC fluxes measured with sediment traps supplied only ~25% of the estimated community respiration, indicating the presence of other carbon supplying mechanisms to the coral community such as biodeposition and feeding on zooplankton. These data on biodeposition, vertical carbon fluxes and respiration suggest that CWC reefs could play an important role in carbon cycling along continental margins
Design, Development and Modeling of Supra- and Biomolecular Systems Using Spectroscopic Methods
No full textThe seemingly weaker interactions involved in non-covalent supramolecular systems play an instrumental role in the chemistry of life. This doctoral thesis deals with the modeling, design, and development of such interactions and systems from a photophysical as well as synthetic perspective. A broad survey of numerous uorescent host−guest ensembles in aqueous solution has been conducted and their photophysical properties have been discussed. These generally involve the complexation of typical macrocyclic hosts, such as cyclodextrins, calix[n]arenes and cucurbit[n]urils, with various classes of uorescent dyes. Furthermore, the range of current as well as future applications of such complexes towards the development of uorescence tags, analyte sensing, as well as enzyme assays has been brie y explored. This is followed by a theoretical modeling of the thermodynamics of such host−guest systems and sheds light on how they can be designed and optimized.
Theoretical modeling has also been employed to investigate the effects of diffusion in the folding of short polypetides by using Förster resonance energy transfer (FRET) measurements. The novelty of this method lies in the combination of two FRET donoracceptor reporter pairs having comparable Förster radii, which are small enough to provide accurate information on end-to-end distances in these polypeptides.
The catalytic properties of cucurbit[n]urils in the hydrolysis of a number of acidlabile functional groups has also been investigated. The results showed that while cucurbiturils enhanced the rate of hydrolysis for amide and carbamate substrates, the most impressive rate accelerations were obtained in the hydrolysis of the oxime substrate. Furthermore, the catalytic activity of the macrocycles could be verified via inhibition studies.
Finally, efforts to photochemically functionalize the relatively stable cucurbit[n]uril macrocycles have been documented. This environmentally friendly method avoids the use of harsh oxidising agents and is conducted in aqueous solution. While it leads to very promising results in terms of reaction yields, procedures to effectively isolate the final product are yet to be developed
Second-Party Quality Auditing in the Automotive Industry: In-depth Methodology Analysis
No full textToday automotive producers operate on a global market with very strong competition and vast variety of customers, each with their own preferences. Under these conditions automotive companies need to provide products of excellent quality in order to stay in business. However, managing quality in the automotive production is a particularly demanding task due to the fact that automotive Original Equipment Manufacturers (OEM) have some of the most intricate production networks which exist. They are involved in only about 20% to 40% of the actual production process and the trend is that in the future this share will keep on shrinking. Therefore OEMs should make sure that they cooperate only with reliable and quality capable business partners. Supplier auditing is a very important quality management tool, which is used to assess the capability of a particular supplier to deliver products of high quality and therefore its suitability as a business partner. Quality auditing is employed before awarding contracts and during the series production to assess the quality risks down the supply chain. This work studies the ability of supplier quality auditing in the automotive industry to provide reliable process capability evaluations. The case study presented here was carried out in cooperation with Volkswagen AG and evaluates the effectiveness of the supplier auditing process at the German automotive manufacturer with respect to the challenges on the global automotive market. This paper employs a research approach for assessment of the quality auditing process, which draws similarities to sampling - an important measurement method in the field of Electrical Engineering. The discussion points out important aspects for the technical implementation of the quality audit in the automotive industry as well as critical points regarding the information management of audit evaluation records. Even though the focus of this work is on the automotive industry, the analytical approach and the statistical methods used here can be used to assess the effectiveness of supplier quality auditing also in other industry sectors
Fibrous Adsorbents as Novel Chromatography Matrices for Enhancing Industrial Downstream Processing of Bioproducts
No full textThe high demand for the production of biopharmaceuticals is limited by the total available manufacturing capacity, process efficiency and cost in a biotechnology industry mainly due to bottlenecks in the downstream processing (DSP) of the products. Downstream purification by traditional packed bed chromatography adsorbents plays a central role which exhibit major limitations, as a consequence the biopharmaceutical industry requires alternative materials and systems to replace. This PhD thesis is aimed at developing adsorption systems based on novel ion-exchange fibrous adsorbents for efficient and cost effective solutions to industrial downstream processing of bioproducts. In this work, strong cation exchange composite fibrous adsorbents have been developed and characterized. The mentioned system showed high capacity and high throughput for chromatography performance that can be used in intermediate purification and also exhibited superior performance during early protein capture application utilizing a model protein from an artificial crude feed stock. Similarly, strong anion-exchange fibrous adsorbents have been developed and characterized as high capacity chromatography support and investigated for their mass transfer properties. The fibrous geometry system demonstrated the potential for use in column scalable operations with high binding capacity and high throughput. A scaling prototype chromatography cartridge system based on the functionalized fibrous adsorbents has been evaluated and demonstrated superior hydrodynamics and process performances compared to commercial columns for industrial downstream processing. Finally, in this research work, the real application of fibrous base adsorbents has been successfully demonstrated as chromatographic support as an alternative to commercial beads in a single step capture and large-scale purification of an algal product, beta-Phycoerythrin, from unicellular marine algae using the mentioned system
Social cost benefit analysis and energy policy
No full textThe energy sector has changed considerably over the past few years, with more changes to come. Both liberalisation and the trend towards a less CO2-intensive society require a lot of different policy measures. Policymakers choices impact society; most policies benefit some actors but hurt others. This uneven distribution of effects makes it difficult for the government to choose the best welfare-maximizing policy. A social cost benefit analysis (SCBA) can help in this choice by quantifying and valuing all of a policys effects for the whole society and not just for the decision maker. This thesis starts with two introductory chapters and contains six papers that focus on three policy topics: the cost of supply interruptions, ownership unbundling of the Dutch energy distribution companies and investments in interconnectors
Protein Engineering for Photobiological Hydrogen Production
No full textDevelopment of renewable energy is essential in achieving economic growth goals and to help address the persisting world's energy crisis. Hydrogen a promising fuel source has higher energy content than oil. Here, we report for the first time (according to our knowledge) the potential application of oxygen tolerant artificial hydrogenases for the biological production of hydrogen, the up-coming alternative fuel. We created Synechocystis sp. PCC 6803 strains that photoautotrophically produce hydrogen. Transformation of wild-type Synechocystis (WT-PCC6803) was performed using an integrating or a self-replicating shuttle vector plasmid to introduce the newly engineered hydrogenase genes tolerant to oxygen, into the Synechocystis sp. PCC 6803 under the influence of the very efficient, light driven psbAII promoter or under copper repressible promoter, respectively. PCR based assays were used to screen for stable transformants. Laboratory made photobioreactor systems were established for the experimental design and data acquisition for the analysis of the Synechocystis sp. 6803 cell cultures and hydrogen production. The systems described here produced on average 15 ppm H2. We showed that H2 production was due to the enhanced expression of the artificial enzyme as untransformed microorganisms produced hydrogen closer to the background value (1ppm). These results demonstrate that it is possible to channel the energy from sunlight into hydrogen gas. Methylation pattern of the bacterial genome Abstract Methylation of DNA by the Escherichia coli DNA adenine methyltransferase (EcoDam) plays a pivot role in providing signals that influences and controls various biological processes in the bacterial cell, ranging from gene regulation and phase variation, mismatch repair, to transcription. Additionally, DNA methylation at the origin of replication is believed to play a significant role in chromosome replication and cell cycle. In the first part of this research work, we were able to analyzed and establish the relationship between the methylation of GATC sites at the origin of replication and growth phase. It was observed that the origin of replication (oriC) is kept in hemi-methylated state for nearly one-third of the cell cycle. Furthermore, we were able to determine methylation delay of DNA in the cell after replication. It was also observed that the relative activity of EcoDam reduces as cells approaches stationary phase. Additionally, we analyzed the methylation profile of the entire bacterial genome by the controlled expression of EcoDam in E. coli SCS110 cells. It was later observed that, after induction, EcoDam is capable of methylating the entire bacterial genome within 5 min. This gave a clear indication on how active EcoDam is
Resource Allocation in OFDM Based Wireless Relay Networks
No full textThe combination of relay transmission with orthogonal frequency division multiplexing (OFDM) technique is deemed as the candidate for the fourth generation (4G) wireless networks. This thesis addresses the resource allocation problem in OFDM based relay networks. Different scenarios of relay networks are considered, e.g., the multi-user relay networks, the multi-relay networks, and the cognitive radio (CR) relay networks. The resource management strategies are developed to analyse: how to optimally distribute available resources among different users, how resource optimization enhances the performance under cooperative communication, how to maximize the lifetime of multi-hop wireless sensor networks (WSNs), and how to improve CR transmission without degrading the performance of the primary network? For each relay transmission scenario, two or more resources are optimized to enhance the system performance under various constraints. The resources include: the power allocation at the source terminal, the power allocation at the relay nodes, the sub-carrier allocation among different users, and the sub-carrier matching over different hops. Multi-user transmission adopts orthogonal frequency division multiple access (OFDMA) technique and is subject to separate power constraint at each terminal. Initially, the resource management issue in multi-user uplink relay transmission is discussed. Then, the similar resource allocation problem is solved when OFDMA multi-user system operates under the bidirectional relay transmission. The multi-relay dual hop transmission is optimized under different transmission schemes, specifically, the non-orthogonal transmission where all the terminals transmit simultaneously in the second time slot and the time division multiple access (TDMA) based transmission where each relay transmits in the pre-defined time slot. The resource allocation in CR relay networks is considered which ensures that the interference caused by the secondary network is not harmful to the primary system. Convex optimization techniques are exploited to solve the problems for each relay transmission and the near optimal solutions are developed. Further, several suboptimal algorithms are also designed to reduce the computational complexity