Piercing problems arise often in facility location, which is a well-studied area of computational geometry. The general form of the piercing problem discussed in this dissertation asks for the minimum number of facilities for a set of given rectangular demand regions such that each region has at least one facility located within it. It has been shown that even if all regions are uniform sized squares, the problem is NP-hard. Therefore we concentrate on approximation algorithms for the problem. As the known approximation ratio for arbitrarily sized rectangles is poor, we restrict our effort to designing approximation algorithms for unit-height rectangles. Our e-approximation scheme requires <I>n</I>^{<I>O</I>(1/&epsilon;??)} time. We also consider the problem with restrictions like bounding the depth of a point and the width of the rectangles. The approximation schemes for these two cases take <I>n</I>^{<I>O</I>(1/&epsilon;)} time. We also show how to maintain a factor 2 approximation of the piercing set in <I>O</I>(log <I>n</I>) amortized time in an insertion-only scenario.

In this thesis we investigate wall-crossing phenomena in the stability manifold of an irreducible principally polarized abelian surface for objects with the same invariants as (twists of) ideal sheaves of points. In particular, we construct a sequence of fine moduli spaces which are related by Mukai flops and observe that the stability of these objects is completely determined by the configuration of points. Finally, we use Fourier-Mukai theory to show that these moduli are projective.

The global analysis fields of the Met Office stratospheric assimilated data set have been investigated. Systematic biases for select years were identified through val- idation with independent satellite observations. Particular attention was given to analyses from January 2005 to October 2009 produced from a 50 level (L50) configuration of the UM with model lid at ∼0.1 hPa, and the impact on analyses fields from November 2009 to September 2010 when the middle atmospheric configuration of the UM was extended to ∼0.01 hPa using 70 levels (L70). Validation results from both the L50 and L70 analyses show that largest tem- perature biases occur at polar latitudes approaching the model lid in the meso- sphere, exhibiting a clear seasonal cycle. Here cold biases in the winter season of the L50 analyses and warm biases in the summer season of the L70 analyses would strongly suggest that the mean meridional circulation in the mesosphere is underestimated, and that small scale gravity wave forcing supplied by the op- erational Ultra Simple Spectral Parameterisation (USSP) scheme is insufficient. Based on the above validation results numerous experiments were conducted to investigate the temperature response in the mesosphere to increased gravity wave forcing. Such experiments concentrated on tuning the energy scale factor (β) in the USSP scheme and the application of a momentum conserving ”opaque” lid. Furthermore, the impact of developing the USSP scheme to include direct heating from gravity wave induced turbulent dissipation was also investigated. Maximum temperature responses in the summer polar upper mesosphere of ∼22 K were found when increasing the standard value of β=0.1 to β=0.14 combined with the application of an opaque lid. Magnitudes of direct heating rates due to gravity wave turbulent dissipation diagnosed via the USSP scheme were found to be consistent with previous estimates. However applying such heating would most likely have a negative impact on the L70 analyses, which already display warm biases in the upper mesosphere, strongly suggesting that additional phys- ical processes such as eddy diffusion must also be accounted for when applying direct heating from gravity wave breaking.

In this work we present the first implementation of the incremental scheme for coupled cluster linear-response frequency-dependent dipole polarizabilities. The implementation is fully automated and makes use of the domain-specific basis set approach. The accuracy of the approach is determined on the basis of a test suite of 47 molecules and small clusters. The local approximation in the coupled cluster singles and doubles polarizability exhibits a mean error of 0.02% and a standard deviation of 0.32% when using a third-order incremental expansion. With the proposed approach, it is possible to compute polarizabilities with larger basis sets compared to the canonical implementation and thus it is possible to obtain higher total accuracy. The incremental scheme yields the smallest errors for weakly-bound and quasi-linear systems, while two- and three-dimensional (cage-like) structures exhibit somewhat larger errors as compared to the full test set. / Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

Non disponible. / Aerosol particles are ubiquitous in the Earth’s atmosphere. Although a minor constituent of the atmosphere, the aerosol particles are linked to visibility reduction, adverse health effects and heat balance of the Earth. The secondary aerosols which are formed in the atmosphere from the gaseous phase : precursor gases become particles by nucleation and condensation (Seinfeld and Pandis, 1998) represents the largest source in a number concentration of atmospheric particles. The chemical reactions can play an important role by turning high volatility gases into species with low vapor pressure and thus high saturation ratio, i.e. creating favorable conditions for particulate matter formation. In this work the CHIMERE chemical transport model is used to ameliorate our understanding of the governing processes for aerosol formation and to investigate its capability to reproduce the mass and number concentrations and temporal evolution of the aerosols particles at high altitudes (as for example Puy de Dome research station), and in particular, evaluate its capacity to simulate the formation of new particles due to nucleation. For the studied cases it was investigated the impact of : a fine resolution topographical database on the accuracy of simulation of dynamical parameters at high altitude, of the use of different emissions databases in the accuracy of gas-phase and aerosol concentration predictions, what is the most adequate nucleation parameterization scheme for simulating new particle formation at high altitude and what is the influence of the choice of the primary particle size distribution on the prediction of new particle formation. Also the ability of the different theories to reproduce the occurrence or lack of a nucleation event is evaluated.

This diploma thesis summarizes recent knowledge about body scheme, spatial orientation and their change in context of chronic pain. The purpose of this work is to find out if chronic pain negatively affects the body scheme and spatial orientation. The thesis includes a comparative analysis of experimental measurements between the patients with Failed Back Surgery Syndrome and healthy control group. The analysis compares tasks based on spatial orientation and body scheme tests. Results show the patients' group having lower results in body scheme related tests, showing a noticeable disparity compared to the control group's test scores. These results were further supported by portion of spatial orientation based tasks, where patients' group again performed at significantly lower level than the control group. In conclusion, our thesis, along with other academic works, states that there is a correlation between chronic pain, disrupted body scheme and spatial orientation. However, at the present time it could not be determined whether the pain precedes the effect of disrupted body scheme or vice versa. Powered by TCPDF (www.tcpdf.org)

Arthroderma benhamiae has been almost unknown among clinical mycologists but it is a cause of around 40 % of dermatophytic infections according to current studies in the Czech Republic. The species is primarily transmitted to humans from guinea pigs and other rodents. The epidemiological situation is similar in other countries in Central and Western Europe. The reason of significant increase in the incidence of infections has not been identified yet, and no sufficiently informative molecular markers have been developed for typification of the species that could help to resolve the cause of this problem. For the purposes of this study, isolates (n=268) from cases of human and animal dermatophytoses from the Czech Republic, Germany, Belgium, Switzerland, Italy, Japan and USA were selected. Ten variable microsatellite markers were developed and sequence analysis of two genetic loci (ITS rDNA and gpdh gene) were performed to reveal intraspecific variation. Phenotype was also studied at the level of micro- and macromorphology of the strains and growth parameters at several temperatures and on several cultivation media. Mating type idiomorph of each isolate was determined and mating experiments were performed by crossing pairs of genetically related as well as genetically distant strains. Sequence...

Title: An examination of pelvic floor activity following the application of special exercises Objectives: The aim of this thesis is to validate the usefulness of carrying out local pelvic floor muscle examinations as an indication and education for therapy. A second objective is for the women involved in the research to subjectively evaluate the examination methods and therapy. Furthermore, the thesis aims to establish an example of a comprehensive and detailed local examination of the pelvic floor muscles. Methods: We measured the pelvic floor activity per vaginam using an EMG biofeedback device on clients with a pelvic floor dysfunction and grade I stress incontinence symptoms. Based on the results of the examination, therapy using the vaginal device was recommended and in six weeks a follow-up examination was carried out. The changes in pelvic floor activity were evaluated by comparing the initial and follow-up examinations. Thus the usefulness of carrying out an examination of the local pelvic floor muscles before indicating a therapy was validated. At the end of the examination an interview with participating clients was conducted in order to subjectively evaluate the method. Results: All of the women participating in the research had previously undergone a different method of pelvic floor...

The Emission Trading Scheme for green house gases is a key tool of European climate protection. Including the road transport sector might be a promising strategy to limit its CO2 emissions. This could be realized within a common market (trans-sectoral trading permitted) or separated markets (trans-sectoral trading not permitted). Starting from different assumptions on emission reduction objectives, the impact of both options is analyzed using a quantitative model. Although an emission trading scheme is ecologically effective regardless of the trading model, it turns out that CO2 emissions and emission allowance prices differ strongly between both design options due to sector specific price elasticities of allowance demand. (authors' abstract)

M.Sc. / Water resources in South Africa are scarce and need to be protected and managed in a sustainable way for future generations. Food supply is a great priority worldwide and the pressure to produce enough food has resulted in the expansion of irrigation and the steadily increasing use of fertilizers and pesticides to achieve higher yields. Rivers are impacted by agriculture through increased suspended sediment loads (which affects primary production, habitat reduction and introduction of absorbed pollutants), elevated nutrient inputs (which may increase the abundances of algae and aquatic plants), salinization and pesticide runoff (which eliminates species intolerant to these conditions and therefore impacts on the normal production of the river system). Aquatic biota plays an integral part in the functioning of aquatic ecosystems. Biological monitoring is used to assess ecosystem health and integrity. Biological communities reflect the overall integrity of the river ecosystem by integrating various stressors and therefore provide a broad measure of their synergistic effects. The research area falls within the Lower Vaal Water Management Area (WMA), which lies in the North-West and Northern Cape Provinces. The lower Vaal River and the Harts River (one of the tributaries of the Vaal) are the river systems under investigation in this study. Farming activities ranges from extensive livestock production and rain fed cultivation to intensive irrigation enterprises at Vaalharts (such as maize, cotton and groundnuts). The Vaalharts is the largest irrigation scheme in South Africa. Salinity is of concern in the lower reaches of the Harts- and Vaal Rivers, due to saline leachate from the Vaalharts irrigation scheme. Agricultural inputs are known to affect aquatic communities and chemicals (e.g. pesticides, herbicides, fertilizers) are extensively used in the Vaalharts irrigation scheme. At present there are no data on the effect of these chemicals on the aquatic biota of the lower Harts- and Vaal Rivers. The aims of this study were to assess the diatom- and macroinvertebrate community structures, ecosystem integrity and macroinvertebrate feeding traits (functional feeding groups – FFGs) in relation to land use.