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(Un)Happiness during Transition: Levels, Distribution and Determinants of Subjective Well-Being in Post-Socialist Countries
No full textThe social costs of transformation from socialism to capitalism gave rise to widespread discontent with the course of transition reforms, and the status anxiety, insecurity, and uncertainty in coping with the difficulties of everyday life that came along with the system change have pervaded people’s lives. Unhappiness and dissatisfaction with life have appeared as dominant sentiments in post-socialist societies. This dissertation has investigated how (un)happiness in post-socialist countries has been influenced and structured in post-communist countries by using a longitudinal comparative perspective. The present study set out (1) to describe and monitor the distribution of subjective well-being during the course of market transformation and to explain the macro-level determinants of happiness inequality across post-communist countries; (2) to shed new light on the social cost of market transformation through suggesting life satisfaction as an alternative tool to examine the dynamic and complex structure of distribution of well-being among different socio-economic groups, thereby overcoming the limitations of using the dichotomy of ‘winners and losers’; (3) to understand the relationship between transition legitimacy, i.e. attitudes towards economic and political liberalization, and people’s subjective well-being in post-socialist countries. This dissertation followed a quantitative cross-national comparative research design, using secondary data sets including cross-national survey data and databases for economic, political, and social development indicators which cover approximately three decades of market transition. The six waves of the World Values Survey (WVS) and European Values Study (EVS) (1982 - 2014), and two waves of the Life in Transition Survey (LiTS) (2006 and 2010), were used as the main data source for the empirical studies
Effect of Internal and External Electric Fields in Organic Semiconductor Systems: Experimental Studies in Frequency and Time Domain
No full textLaser spectroscopy is a powerful tool for the investigation of structural and dynamical changes in diverse material systems. The work presented in this thesis is focused on the investigation of organic semiconductors. Work has also been done on ionic liquids, which also present a highly attractive substance class. In the first part of the Ph.D. thesis, time-resolved studies of the effect of an external static electric field on dynamical properties of an organic semiconductor-based system are presented. The important processes in organic semiconductor devices strongly depend on the presence of internal and external electric fields. This is important when trying to understand the generation and decay mechanism of charge pairs generated in organic semiconductor-based devices. Here, we have used femtosecond transient absorption spectroscopy to investigate the polaron pair dynamics in neat Poly (3-hexylthiophene-2,5-diyl) (P3HT) thin films and P3HT films sandwiched between different electrical contacts in presence of external static electric field. Field-induced dissociation of polaron pairs, generated after photoexcitation mainly from hot excitons, to charge carriers is observed in the P3HT device increasing the reverse bias. We have also studied the polaron-pair dynamics of a typical donor/acceptor heterojunction device made from phenyl-C61-butyric acid methyl ester (PCBM) as acceptor and P3HT as donor with different donor/acceptor concentration. In the second part of the thesis, we have used density functional theory (DFT) to model different systems. We have investigated the effect of external fields on structural parameters in P3HT and the change in reorganization energy and hence the electron-phonon coupling ‘Huang-Rhys factor’, due to change in external electric field in P3HT, have been calculated. In addition, here, we provide a summary of our work on ionic liquid systems on water-ionic liquid interactions in frequency domain using Raman spectroscopy and DFT
The murine cytomegalovirus immunoevasin gp40/m152 inhibits activation of NK cell receptor NKG2D by intracellular retention and cell surface masking of RAE-1 gamma ligand
No full textNKG2D is a crucial Natural Killer (NK) cell activating receptor, and the murine cytomegalovirus (MCMV) employs multiple immunoevasins in order to avoid NKG2D-mediated activation. One of the MCMV immunoevasins, gp40 (m152), downregulates the cell surface NKG2D ligand, RAE-1 gamma, thus limiting NK cell activation. My study establishes the molecular mechanism by which gp40 retains RAE-1 gamma in the secretory pathway. Using flow cytometry and pulse chase analysis, I demonstrate that gp40 retains RAE-1 gamma in the early secretory pathway, and that this effect depends on the binding of gp40 to a host protein, TMED10, a member of the p24 protein family. I also show that the TMED10-based retention mechanism can be saturated, and that gp40 has a backup mechanism as it masks RAE-1 gamma on the cell surface, blocking the interaction with the NKG2D receptor and thus NK cell activation
Quantum Aspects of Cosmology
No full textIn the present work we examine the cosmological horizon problem from a quantum mechanical to effectively quantum gravitational perspective.
Spacetime coarse graining is a basic property of many quantum gravitational theories. In this spirit, noncommutative and nonassociative models yield spacetime uncertainties. A small time uncertainty is enough to solve
the horizon problem without adding a cosmological inflationary process, because this small time uncertainty induces an infinite spatial uncertainty on the initial hyperplane. We interpret this as maximal quantum entanglement of the cosmological quantum state. We analyze
a non-local deformation of quantum field theory; the canonical equal time commutation relations of a scalar quantum field with its canonical momentum allow for an isotropic and homogeneous deformation which incorporates violation of microcausality. The physical core of this consideration can be traced back to a deformed dispersion relation in the Hamiltonian, which allows quantum
correlations across the classical light cone. This explicitly Lorentz-violating model furthermore allows to calculate the deformation in the quantum fluctuation spectrum.
In order to measure the initial entanglement it is
necessary to consider a particle probe which propagates on
(quantum) spacetime. The correct quantization of this probe
including spin, interactions and gravity, needs a common
mathematical framework for the classical theory. For this
purpose, we consider graded Poisson brackets which are
deformed via gauge interactions and gravity. We show that
the bosonic string and the (spinning) relativistic particle
can be coherently formulated via this approach.
Ultimately, models have to be compatible with physical
observations. In this work we describe two methods which
are used to investigate the temperature fluctuations of the
Cosmic Microwave Background for deviations from Gaussianity
and Isotropy: multipole vectors and pseudo entropies
Host-Guest Reporter Pairs for Fluorescence Monitoring of Enzymatic Reactions and a Supramolecular Relay Process
No full textCompared with traditional synthetic chemistry, supramolecular chemistry focus on systems
organized by noncovalent interactions. Host-guest chemistry is a vigorous field of supramolecular chemistry. However, researchers have paid lots of attention mainly in thermodynamics of host-guest binding, while their kinetics did not receive enough concern. Actually, kinetics investigation provides more information than thermodynamics, especially related to mechanism.
In this thesis, we try to inspect the host-guest binding from the perspective of kinetics. For example, fast-exchanged host-dye reporter pairs are used for monitoring slower process. Slow-exchanged rotaxanes are stable enough to be used as functional materials.
In Chapter 1, we briefly introduced the host-guest chemistry and supramolecular kinetics. In Chapter 2, we used two reporter pairs to monitor reaction of kinase and phosphatase, as well as screening inhibitor. In Chapter 3, a supramolecular relay process of CBs and a putrescine derivative of aminomethyladamantane has been monitored by reporter pairs, in a ratiometric manner. In Chapter 4, a series of kinetically stable polyrotaxanes constructed by CDs and conjugated polymers have been synthesized and characterized, they are potential materials for optoelectronic applications. In Chapter 5, amphiphilic calixarenes were investigated as counterion activators for peptide transport, both through synthetic lipid membrane and cell membrane, by lowering the kinetic barrier
Chemistry of Cocoa Bean Roasting
No full textThis thesis aims to use mass spectrometric chemical profiling methods to deepen the scientific understanding of roasting of cocoa with an emphasis on its organoleptic properties.
A series of cyclic dipeptides (2,5-diketopiperazines or DKPs) responsible for the bitter taste of cocoa was studied. Along already known to the literature, new species were identified, and a kinetic model of their formation was established. Their relative concentrations were correlated with their putative peptide precursors in the raw material. Significant positive correlations indicated that short peptides in unroasted cocoa formed during fermentation are taste precursors for bitter 2,5-diketopiperazines. Additionally, it was shown that most DKPs were generated during the degradation of the single most abundant peptide precursor.
Furthermore, an investigation of Maillard reaction during cocoa processing, demonstrated a higher than suspected so far variety of Amadori compounds. These first stable reaction products of simple sugars with amino acids were proven to form from oligopeptides as well. Their generation and degradation trends were shown for the first time on cocoa beans processing series from Ghana. Fermentation, drying, and roasting changes of other components such as oligopeptides, sugars, aroma volatiles were illustrated as well.
Finally, an HPLC-MS based design of experiments model of cocoa roasting was established. Standard process parameters, such as time, temperature, the addition of water, acid and base, were investigated to demonstrate their influence over the chemical composition of the resulted product. Relative concentrations of procyanidin monomers, dimers, and trimers, an Amadori compound, and a peptide were considered as markers. For each, high-quality models were accomplished and validated, which displayed sound prediction accuracy. These proof-of-concept results show great promise in the optimization of cocoa roasting
Tactile Attenuation of Visual Search Performance Deficiencies in Low Luminance Environments
No full textDiverse adaptive visual processing mechanisms allow us to complete simple discrimination and more complex visual search tasks in a wide visual photopic range (> 0.6 cd/m2). Despite extensive research ranging from the psychophysical to neurophysiological disciplines, none has examined how these processes behave in the scotopic and low - mesopic luminance ranges, even though we still utilize these processes daily albeit facing considerable decreases in performance. Characterization of perceptual and environmental limitations are needed. Furthermore, visual performance is often enhanced by innate visual - tactile mechanisms, and if patterned properly, application of additional tactile information could attenuate observed decreases in the low luminance spectral ranges. This dissertation will first demonstrate novel behavioural performance efficiency functions for visual discrimination and visual search as one traverses the scotopic to low - mesopic luminance ranges. Second, will demonstrate how various properties of tactile encoding can either attenuate behavioural deficiencies or even facilitate normal performance. Third, these results are supported from both behavioural (eye tracking) and neurophysiological (event related potential) analyses, isolating critical temporal gating windows with more efficient search patterns mediated via a central - parietal network
Engineering the central carbon metabolism of Saccharomyces cerevisiae for succinic acid production from glycerol
No full textGlycerol is an attractive carbon source in industrial biotechnology because its conversion into the glycolytic intermediate pyruvate via the glycolytic pathway produces twice the amount of reducing equivalents (per carbon equivalent) compared to glucose. This enables higher maximum theoretical yields of metabolic products whose production pathways require more reducing equivalents in the form of NADH such as succinic acid (SA). Since Saccharomyces cerevisiae does not naturally produce SA at high levels, extensive metabolic engineering is necessary to increase SA production. Therefore, the first part of the thesis consists of a review of the state-of-the-art regarding the S. cerevisiae growing on glycerol, which highlights the importance of gaining more knowledge about the carbon catabolism during growth of S. cerevisiae on this carbon source. This thesis also presents novel findings regarding the anaplerotic reactions active during growth of S. cerevisiae on glycerol. In comparison to glucose or ethanol as carbon sources, S. cerevisiae shows a higher metabolic flexibility with regard to the active anaplerotic reactions during growth on glycerol. The knowledge gained from investigating the anaplerotic reactions proved to be essential for engineering S. cerevisiae for SA production through the redox-neutral pathway, i.e. glycerol catabolism via the NAD+-dependent pathway and SA production through the cytosolic reductive branch of the TCA cycle (referred to as ‘SA module´). The data presented in this thesis shows for the first time SA production from glycerol in S. cerevisiae. Although the SA was not produced via the initially envisaged pathway, i.e. ‘SA module’, the experimental data provides a solid basis for future work focusing on further metabolic engineering to channel the carbon flux through the desired pathway for achieving redox-neutral production of SA
The Impact of Production Order Interdependencies on Logistics Performance
No full textCommonly, methods applied in production planning may lead to production orders flowing
across similar sequences of machines within similar periods of time. However, within such
spatiotemporal neighbourhoods, interdependency effects among production orders may arise,
causing compounding delays. The importance of anticipating interdependencies amongst
production orders during production planning is key to accurately predict logistics performance such as lead time or expected delays. This is a challenging task for production planners, as interdependencies arise during operations, are difficult to foresee, and can be caused by a multitude of different factors. Only little research has been carried out to establish a generic and measurable understanding of the root-causes of interdependencies in manufacturing systems. In other research areas, such interdependency effects are explored as a key impact factor on system performance. Particularly in physics, research on granular matter systems has led to the development of multiple theories and concepts of particle-particle interactions, summarised here as Granular Matter Theory (GMT). In this thesis, we draw on these concepts in order to define and measure interdependency effects for manufacturing systems and discover a negative relation between to logistics performance indicators. Furthermore, we provide first evidence on some structural and non-structural impact factors that drive such effects and derive recommendations for practitioners in production planning
Potentially pathogenic Vibrio species in the German Bight, North Sea
No full textVibrio spp. are ubiquitous bacteria, common to estuaries and coasts. V.parahaemolyticus, V.vulnificus and V.cholerae are the main water-related pathogenic species, able to cause serious gastroenteritis, wound infections or septicaemia. Infection cases have become more frequent in northern temperate waters, attributed to climate change related events. Little is known about pathogenic Vibrio spp. in the German Bight. Occurrence, abundance and pathogenicity of V.parahaemolyticus, V.vulnificus and V.cholerae were investigated in a salinity gradient of the German Bight over 14 months. Seasonal patterns with increased abundances during summer were detected, while extended periods of warm seawater coincided with prolonged Vibrio spp. occurrences in the German Bight. Temperature and nitrite were the significant factors explaining variations in Vibrio spp. abundances. This study revealed that environmental human pathogenic Vibrio spp. comprise multiple virulence-associated genes in the German Bight, especially in estuarine regions. Pathogen growth potentials of clinically relevant V.vulnificus and V.cholerae strains were investigated in the German Bight to determine the extent of in vitro growth in a broad range of physico-chemical conditions of surface waters originating from a salinity gradient. Those strains, despite revealing different growth patterns, are capable of growth in most seawater samples under ambient physicochemical conditions. Growth kinetics showed strong temperature dependency when grown in seawater, while no salinity dependency was detected. Potentially pathogenic V.parahaemolyticus was detected on marine microplastics for the first time, evidencing that microplastics can serve as additional surfaces for attachment and function as vectors for the enrichment and dispersal. Given the future predictions of climate variability, a species-specific monitoring and risk assessment regarding potentially pathogenic Vibrio spp. in the German Bight is crucial