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1. The study confirms an association between transverse arch dimensions and severity of ankyloglossia, which reflects relationship between molar difference and free tongue. 2. Molar difference in group A (complete and severe ankyloglossia cases) has high negative values (average -4.38) which was much smaller than the data from the literature concerning many different types of occlusion. 99 3. The exact relation between transverse arch dimension and severity of ankyloglossia needs further research.
The present work is the first work dealing with turbulence in the WEGA stellarator. The main object of this work is to provide a detailed characterisation of electrostatic turbulence in WEGA and to identify the underlying instability mechanism driving turbulence. The spatio-temporal structure of turbulence is studied using multiple Langmuir probes providing a sufficiently high spatial and temporal resolution. Turbulence in WEGA is dominated by drift wave dynamics. Evidence for this finding is given by several individual indicators which are typical features of drift waves. The phase shift between density and potential fluctuations is close to zero, fluctuations are mainly driven by the density gradient, and the phase velocity of turbulent structures points in the direction of the electron diamagnetic drift. The structure of turbulence is studied mainly in the plasma edge region inside the last closed flux surface. WEGA can be operated in two regimes differing in the magnetic field strength by almost one order of magnitude (57mT and 500mT, respectively). The two regimes turned out to show a strong difference in the turbulence dynamics. At 57mT large structures with a poloidal extent comparable to the machine dimensions are observed, whereas at 500mT turbulent structures are much smaller. The poloidal structure size scales nearly linearly with the inverse magnetic field strength. This scaling may be argued to be related to the drift wave dispersion scale. However, the structure size remains unchanged when the ion mass is changed by using different discharge gases. Inside the last closed flux surface the poloidal ExB drift in WEGA is negligible. The observed phase velocity is in good agreement with the electron diamagnetic drift velocity. The energy in the wavenumber-frequency spectrum is distributed in the vicinity of the drift wave dispersion relation. The three-dimensional structure is studied in detail using probes which are toroidally separated but aligned along connecting magnetic field lines. As expected for drift waves a small but finite parallel wavenumber is found. The ratio between the average parallel and perpendicular wavenumber is in the order of 10^-2. The parallel phase velocity of turbulent structures is in-between the ion sound velocity and the Alfvènvelocity. In the parallel dynamics a fundamental difference between the two operational regimes at different magnetic field strength is found. At 500mT turbulent structures can be described as an interaction of wave contributions with parallel wavefronts. At 57mT the energy in the parallel wavenumber spectrum is distributed among wavenumber components pointing both parallel and antiparallel to the magnetic field vector. In both cases turbulent structures arise preferable on the low field side of the torus. Some results on a novel field in plasma turbulence are given, i.e. the study of turbulence as a function of resonant magnetic field perturbations leading to the formation of magnetic islands. Magnetic islands in WEGA can be manipulated by external perturbation coils. A significant influence of field perturbations on the turbulence dynamics is found. A distinct local increase of the fluctuation amplitude and the associated turbulent particle flux is found in the region of magnetic islands.
The human antibody response to experimental colonization with Staphylococcus aureus NCTC8325-4
(2008)
The four main work packages and their most important results are briefly described as following. 1. Characterization of the extracellular proteome of S. aureus NCTC8325-4 Reference maps of the extracellular proteins of S. aureus NCTC8325-4 were produced at pH ranges 6-11 and 4-7. In total, 119 (pH 6-11) and 177 (pH 4-7) protein spots were identified, corresponding to 48 and 114 proteins, respectively. Among them were many well-known virulence factors such as alpha-hemolysin (Hla), beta-hemolysin Hlb, gamma-hemolysin subunits (HlgA-C), hyaluronate lyase (HysA) and staphylococcal superantigen-like protein 11 (Ssl11). We also detected various extracellular enzymes, which can cause tissue degradation and are involved in nutrient acquisition, for example, autolysin (Atl), glycerol ester hydrolase (Geh), lipase (Lip), thermonuclease (Nuc), several serine proteases SplA-F (SplA-F), V8 protease (SspA), cysteine protease (SspB), staphopain thiol proteinase (88195808, SspP). Many of these proteins probably also contribute to the virulence of S. aureus. 2. Optimization of a 2-D immunoblot (IB) method for the comprehensive investigation of IgG binding to S. aureus extracellular proteins (strain NCTC8325-4) The immune proteome of S. aureus NCTC8325-4 was revealed by probing 2-D blots of S. aureus extracellular proteins at the two pH ranges 6-11 and 4-7 with a pool of sera from 16 volunteers. IgG binding was detected with high sensitivity using a peroxidase-coupled secondary Ab in combination with an ECL-substrate. With application of the software package Delta2D, we could clearly define 66 immune reactive spots on the immunoblots (IBs) of pH range 6-11 and 38 spots on IBs of pH range 4-7. 72 of these 104 immune reactive spots could be identified by matching the IBs with the protein reference maps. These spots represented 36 identified proteins, many of which are known virulence factors, or they are involved in bacterial cell wall biosynthesis and degradation. Generally, the most abundant proteins were also highly immune reactive, but there was no strict correlation between protein abundance and immune reactivity. Some low abundance proteins, especially basic proteins, showed high immune reactivity on 2-D IBs, for example, Atl, 88195808 (SspP) and iron-regulated surface determinant protein A (IsdA). On the other hand, we observed proteins, which were present in large amounts but did not bind IgG such as peptidoglycan hydrolase (LytM) and a hypothetical protein 88193909 (SAOUHSC_00094). 3. Determination of the anti-staphylococcal Ab profiles of S. aureus carriers and noncarriers Comparing the serum IgG binding patterns of sera from the 16 individual volunteers, we observed pronounced heterogeneity in total IgG binding, spot patterns and spot intensities. Five spots were stronger in carriers than in noncarriers (P< 0.05, Mann-Whitney U test). These spots represent IgG binding to SspA, SspB, IsaA, and two hypothetical proteins. A principal component analysis based on differential IgG binding to these spots showed that the carriers were more closely related to each other than the noncarriers, but that they could not be clearly separated from the noncarriers. 4. Does experimental colonization induce changes of the anti-staphylococcal Ab profiles? Finally, we tested whether symptom-free experimental colonization of the 16 volunteers with S. aureus NCTC8325-4 elicited an IgG response. When we compared sera obtained before colonization with those taken 4 weeks after the inoculation with the laboratory S. aureus strain, we did not observe major changes in the Ab patterns. We conclude that short- term colonization with a strain of low virulence does not suffice to induce an Ab production, which is comparable to that present already before the colonization. Thus, either long term high density colonization is required, or as we consider most likely, the adaptive immune response is primarily triggered by (minor) S. aureus infections. Taken together, in this work we have separated the soluble proteins from complex extracellular S. aureus protein extracts with good reproducibility, large coverage (pH 6-11 and 4-7) and high resolution. With application of an ECL substrate, our 2-D immunoblotting procedure resulted in the highly sensitive detection of IgG binding over a wide range of signal intensities. The most important finding with this technique was the pronounced variability of anti-staphylococcal Ab profiles in healthy adults. This could well explain differences in susceptibility to S. aureus infection and its complications. The Ab responses are presumably triggered by long-term colonization or, more likely, by minor infections with S. aureus, since experimental nasal colonization of healthy volunteers with a bacterial strain of low virulence did not induce impressive changes in the Ab profiles.
Understanding of the regulatory mechanisms controlling stress gene expression of S.aureus in response to environmental stress is very essential in studying its fitness and virulence. In this work, the changes in protein expression profiles as well as the gene transcription of S.aureus after heat exposure, osmotic stress and in response to the antibiotic puromycin were studied in order to provide detailed insights into the response of S.aureus to various kinds of environmental stress under in vitro conditions, namely: (1) to investigate the global response of S.aureus to heat stress conditions using transcriptomic and proteomic analyses. (2) to study the transcriptome and proteome of S.aureus in response to antibiotic substance puromycin. (3) to define the proteome signatures of S.aureus under NaCl stress condition. (4) to complete the proteome map of cytoplasmic proteins of S.aureus by identifying proteins exclusively synthesized during the exposure to stress. Firstly, the high resolution 2-D protein gel electrophoresis technique combined with MALDI-TOF-MS and a DNA array approach were used to investigate the cellular response of S.aureus to heat stress. A switch from normal growth temperature to high temperature condition revealed complex changes in the protein expression pattern as well as the genes expression profile. The effect of puromycin stress on S.aureus cells was analyzed, using a gel-based proteomic approach and transcriptomic analyses with DNA microarrays. We compared the protein synthesis pattern as well as the transcription data of S.aureus in response to puromycin stress with that in response to heat shock. The results demonstrated that both stress conditions induced specific, overlapping and general responses. Finally, the protein expression profile of S.aureus in response to NaCl stress was analyzed with 2D gel based proteomic approach. Our proteome analyses revealed the repression of the synthesis of many enzymes belong to different metabolism pathways . In summary, the signatures for stress or starvation stimuli can be used as diagnostic tools for the prediction of the mode of action of new antibiotics or for studying the physiological state of cells grown. Expression of the respective genes under in vivo conditions could provide some ideas on the environmental signals that specifically influence the survival of S.aureus within and outside the host.
The study of sow reproduction traits is important in livestock science and production to increase animal survival and economic efficiency. This work deals with the detection of different effects on within-litter variance of birth weight by applying different statistical models with different distributional assumptions. The piglets within one litter were separated by sex. The trait of sow was formed from the sample variances of birth weights within litter separated by sex to consider the sex effect on mean birth weight. A linear mixed model (LMM) approach was fitted to the logarithmized sample variance and the sample standard deviation. A generalized linear mixed model with gamma distributed residuals and log-link function was applied to the untransformed sample variance. Appropriate weights were constructed to account for individual litter sizes. Models were compared by analysing data from Landrace and Large White. The estimates of heritability for the different traits ranged from 6-14%. The LMM for the weighted standard deviation of birth weights was identified as most suitable in terms of residual normality. Furthermore, the impact of piglets´ sex on birth weight variability was tested, but it was only proved for one practical dataset. Additionally, we analysed the influence of including or not including birth weights of stillborn piglets on the estimates of variance components of birth weight variability. With omitted stillborns the estimates of heritability resulted in about 2% higher values than in investigations of total born piglets. We were interested in the presence of the random boar effect on birth weight variability. The corresponding variance component was tested via restricted likelihood ratio test. Among others, the null distribution of the test statistic was approximated by parametric bootstrap simulations which were computational intensive. We picked up a two-parametric approach from literature and proposed a three-parametric approach to approximate the null distribution of the test statistic. We have analysed correlated data in balanced (simulated data) and unbalanced (empirical data) designs. The two-parametric approach using a scaled mixture of chisquare-distributions as well as a three-parametric approach, that uses a mixture of the point mass at zero and a gamma distribution, behaved most solid in all investigations and were most powerful in the simulation study.
The rapid neutron-capture or the r-process is responsible for the origin of about half of the neutron-rich atomic nuclei in the universe heavier than iron. For the calculation of the abundances of those nuclei, atomic masses are required as one of the input parameters with very high precision. In the present work, the masses of the neutron-rich Zn isotopes (A=71 to 81) lying in the r-process path have been measured in the ISOLTRAP experiment at ISOLDE/CERN. The mass of 81Zn has been measured directly for the first time. The half-lives of the nuclides ranged from 46.5 h (72Zn) down to 290 ms (81Zn). In case of all the nuclides, the relative mass uncertainty (∆m/m) achieved was in the order of 1E-8 corresponding to a 100-fold improvement in precision over previous measurements.
The New Zealand coal covering the complete maturity range from peat to high volatile bituminous, thus from early diagenetic to catagenesis coalification levels, has been studied in order to bring out new insights into molecular alterations, macromolecular structural evolution, elemental-compositional changes as function of maturation and to propose which processes cause these changes. As particular note from the previous observations that many immature coals from around the world often have rather high extraction yields. It is uncertain whether or not bitumen affecting on petroleum potential and structural evolution of coals. My purposes were therefore to find out the possible interaction between kerogen and bitumen during pyrolysis, and to elucidate the role of bitumen in defining petroleum potential and structural evolution of coals. Furthermore, it is assumed that low rank coals appear to be well suited for feeding the deep subsurface microbes. The products are released as either CO2 or CO that could be substrates for microbial activity. Thus, in this dissertation, I have calculated the loss of CO2 during diagenesis to give the quantitative feeding potential link to deep biosphere, using a mass balance model. To achieve these purposes, at the primary step, the facies variability as well as the molecular compositional changes within the coal band sequence in regard to distinguish the influences of organofacies and maturity need to be clear. Hence, the first aim was to gather information about depositional environment and insights into the plant communities that have contributed to New Zealand coals. Numerous organic-geochemical techniques were used to analyse the free lipids and macromolecular organic matter. Total organic carbon determination (TOC), bulk δ13Corg isotope analysis, the Rock-Eval pyrolysis, pyrolysis- gas chromatography and infrared spectrometry were performed on the original samples and the residue after solvent extraction. The crude lipid extract was separated into fractions that were then analysed by gas chromatography and gas chromatography-mass spectrometry. The obtained data shows that organic matter of New Zealand coals contains mainly terrestrial higher plant material, with a more or less constant background supply of bacterial biomass, deposited in oxidising environment. Angiosperms contributed as the main proportion of the organic matters. Gymnosperms, particularly the Podocarpaceae, Cupressaceae, Taxodiaceae, Pinanceae and Araucariaceae conifer species, still dominated during the Cretaceous. New Zealand coal is classified as mixed gas- and oil-prone. Hydrogen index values increase from 120 to 280 (mg/g TOC) with increasing maturity, which has been explained by the loss of oxygen during diagenesis. A Transformation Ratio of CO2 (TRCO2) has been formulated here in order to quantify the loss of CO2 for any given coal type. It obviously shows CO2 generation is one of the major features of diagenesis that might feed the deep biosphere. In case of study, about 10 to 105 mg CO2 per gram of total organic carbon have been released during maturation from peat to high volatile bituminous. This is equivalent to 0.23 to 2.4 millimoles CO2 per g TOC. For methanogenesis via CO2 reduction, between 0.92 and 9.6 millimoles hydrogen would be required for complete CO2 reduction during diagenesis. Future work must determine if this is feasible or not. The important role of bitumen in defining the petroleum generation potential was elucidated. The presence of hydrogen transfer agents in bitumen helps to stabilize free radicals hence prevents recombination/ repolymerization processes thus preserving the petroleum generating potential in original coals. Specially, second-order reactions between kerogen and bitumen occurred during pyrolysis that reduce the primary gas yield, but increase the potential secondary gas as well as oil yields. Therefore, it is proposed that pre-extraction of source rocks before pyrolysis, especially coals where extraction yields are particularly high, is not recommended. The comparative investigation with previously studied higher rank Carboniferous German coals showed an excellent fit for both pyrolysis and infrared spectrometry data, suggesting that the New Zealand coals can be considered as natural precursors of the German coals. The structural evolution of coals during maturation is firstly characterized by the enrichment of the aliphatic structures in low rank, peat to high volatile bituminous, then decreases with further maturation. This enrichment of aliphatic carbon content in low rank is accompanied by an increase in the average aliphatic chain length. A slightly enrichment of CH3 group is observed in maturity range 0.9- 2.1% vitrinite reflectance. Secondly, during coalification the content of protonated aromatic carbons increases until R0 ~ 1.6%, then decreases with further maturation.
The term atomic cluster relates to compounds of at least two or three atoms. Thereby the physical properties are size dependent and the property transitions between single atoms and bulk material are not always smooth. Ion traps allow it to observe internal cluster properties independent from the influence of external forces. In this work the electron induced decay of singly negatively charged atomic clusters was observed. The dissociation cross section of the clusters is dominated by detachment of the only weakly bound outer electrons. For simple atoms at low electron energies a simple scaling law can be obtained that includes only the binding energies of the valence electrons. Nevertheless for larger sizes theoretical calculations predict so called "giant resonances" as dominant decay process in metal clusters. Due to mass limitations in storage rings exist so far only cross section measurements for simple anions and small negative molecules. In this work the electron detachment cross sections of small negatively charged carbon (Cn- n=2-12), aluminium (Aln- n=2-7) and silver clusters (Agn- n=1-11) were measured in an electrostatic ion beam trap. The classical scaling law, including only the binding energies of the valence electrons, turned out to be not sufficient, especially for larger clusters. In order to improve the correlation between measured and predicted values it was proposed to involve the influence of the cluster volume and the specific polarisability induced by long range coulomb interaction. For silver clusters the best agreement was obtained using a combination of the projected area reduced by the polarisability. The existence of "giant resonances" could not be confirmed. According to theory for clusters with a broad internal energy distribution, a power-law decay close to 1/time is expected. For some clusters the lifetime behaviour would be strongly quenched by photon emission. The thermionic evaporative decay of anionic aluminium and silver clusters in a size range from one to ten constituents was tested but a correlation could be only found incidentally for a few cluster sizes.
In this work we will analyse the capabilities of several numerical techniques for the description of different physical systems. Thereby, the considered systems range from quantum over semiclassical to classical and from few- to many-particle systems. For each case we address an interesting, partly unsolved question. Despite the different topics we address in the individual chapters, the problems under study are somehow related because we focus on the time evolution of the system. In chapter 1 we investigate the behaviour of a single quantum particle in the presence of an external disordered background (static potentials). Starting from the quantum percolation problem, we address the fundamental question of a disorder induced (Anderson-) transition from extended to localised single-particle eigenstates. Distinguishing isolating from conducting states by applying a local distribution approach for the local density of states (LDOS), we detect the quantum percolation threshold in two- and three-dimensions. Extending the quantum percolation model to a quantum random resistor model, we comment on the possible relevance of our results to the influence of disorder on the conductivity in graphene sheets. Furthermore, we confirm the localisation properties of the 2D percolation model by calculating the full quantum time evolution of a given initial state. For the calculation of the LDOS as well as for the Chebyshev expansion of the time evolution operator, the kernel polynomial method (KPM) is the key numerical technique. In chapter 2 we examine how a single quantum particle is influenced by retarded bosonic fields that are inherent to the system. Within the Holstein model, these bosonic degrees of freedom (phonons) give rise to an infinite dimensional Hilbert space, posing a true many-particle problem. Constituting a minimal model for polaron formation, the Holstein model allows us to study the optical absorption and activated transport in polaronic systems. Using a two-dimensional variant of the KPM, we calculate for the first time quasi-exactly the optical absorption and dc-conductivity as a function of temperature. Concerning the numerical technique, the close relation to the time evolution in the other chapters get clear if we identify temperature with an imaginary time. In chapter 3 we come back to the time evolution of a quantum particle in an external, static potential and investigate the capability of semiclassical approximations to it. Considering various one-dimensional geometries, we address basic quantum effects as tunneling, interference and anharmonicity. The question is, to which extend and at which numerical costs, several semiclassical methods can reproduce the exact result for the quantum dynamics, calculated by Chebyshev expansion. To this end we consider the linearised semiclassical propagator method, the Wigner-Moyal approach and the recently proposed quantum tomography. A conceptually very interesting aspect of the compared semiclassical methods is their relation to different representations of quantum mechanics (wave function/density matrix, Wigner function, quantum tomogram). Finally, in chapter 4 we calculate the dynamics of a classical many-particle system under the influence of external fields. Considering a low-temperature rf-plasma, we investigate the interplay of the plasma dynamics and the motion of dust particles, immersed into the plasma for diagnostic reasons. In addition to the huge number of involved particles, the numerical description of this systems faces the challenge of a large range of involved time and length scales. Exploiting the mass differences of plasma constituents and dust particles allows for separating the PIC description of the plasma from the MD simulation of the dust particles in the effective surrounding plasma.
Multiply negatively charged aluminium clusters and fullerenes were generated in a Penning trap using the "electron-bath" technique. Aluminium monoanions were generated using a laser vaporisation source. After this, two-, three- and four-times negatively charged aluminium clusters were generated for the first time. This research marks the first observation of tetra-anionic metal clusters in the gas phase. Additionally, doubly-negatively charged fullerenes were generated. The smallest fullerene dianion observed contained 70 atoms.