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[en] The objective of this research paper is to analyse the current efforts of country activities towards the 2020 2 C target, in order to identify best practices and their possible impact on emission reduction in 2020. A first scan of policies in countries with high greenhouse gas emissions and countries with remarkably ambitious climate change mitigation strategies (see Table 1) revealed that thematic areas with notable coverage in domestic climate policy are: general strategies and targets, renewable energy support schemes for electricity, product standards and codes for energy efficiency in buildings, and direct subsidies and fuel quotas for renewables in Transport. From this, along with initial indications of mitigation potential, we identified four areas where ambition could be significantly enhanced by 2020.
[en] Austenitic and dissimilar welds with respect to the ultrasonic testing (UT) methods are considered normally as ''difficult-to-test'' objects. During the solidification process in such welds a distinct dendrite microstructure evolves, which is coarse-grained, anisotropic and inhomogeneous simultaneously. The reliability of available ultrasonic methods on austenitic welds depends significantly on the selected UT-parameters as well as on the inspection personnel experience. In the present dissertation, an ultrasonic testing method was developed, which allows the flaw detection and evaluation in acoustically anisotropic inhomogeneous materials, especially in austenitic and dissimilar welds with a quantitative statement to the defect size, type, and location. The principle of synthetic focusing with taking into account the material anisotropy and inhomogeneity along with two- and three-dimensional visualization provides a reliable and quantitative assessment of the inspection results in acoustically anisotropic inhomogeneous test objects. Among others, an iterative algorithm for the determination of unknown elastic properties of inhomogeneous anisotropic materials has been developed. It allows practical application of the developed UT method, since the anisotropy of most of austenitic and dissimilar welds (especially of hand-welded joints) in practice is usually unknown. The functionality of the developed inspection technique has been validated by many experiments on welded austenitic specimens having artificial and natural defects. For the practical application of the new ultrasonic technique different testing strategies are proposed, which can be used depending on the current inspection task.
[en] The decision for or against a potential site for a nuclear waste repository is highly complex and requires decision-makers to consider multiple assessment criteria. The complexity of each site and its characteristics, and the differing opinions among members of the public and advocacy groups mean t hat conflicts of interest are likely to arise. In this paper, the author suggests that multi-criteria analysis models could be used to provide methodological support during the selection process. The models can map these types of decision situations and suggest coherent solutions with relatively little formal effort. They allow users to compare different opt ions simultaneously and ensure that t heir decision-making Is conscious rather than arbitrary.
[en] The environmental impacts of nuclear energy are highly underestimated. Nuclear weapons, atomic bomb tests, and nuclear accidents are considered a danger for the environment and a human cancer risk. However, childhood leukemia is consistently elevated near nuclear power plants and the Chernobyl accident entailed elevated human birth sex ratios across Europe. We studied the annual sex ratio near nuclear facilities in Germany, France, and Switzerland at the municipality level. We will demonstrate that low doses of ionizing radiation cause effects in human beings. This is shown by strongly consistent spatial-temporal shifts in the human sex ratio trends in the vicinity of nuclear facilities. In the chosen countries complete official data on over 70 million gender specific annual births at the municipality level are available. By Lambert-93 coordinates (France) and GK3 coordinates (Germany, Switzerland) we determined the minimum distances of municipalities from major nuclear facilities. Spatial-temporal trend analyses of the annual sex ratio depending on municipalities' minimum distances from nuclear facilities were carried out. Applying ordinary linear logistic regression (jump or broken-stick functions) and non-linear logistic regression (Rayleigh functions) we demonstrate that the sex ratio at birth shows the influence of mutagenic ionizing radiation on human health. As important environmental chemical contaminants are also mutagenic, the usefulness of the sex ratio at birth as a genetic health indicator can be inferred by analogy.
[en] This paper summarizes information about breast MRI to be provided to women and referring physicians. After listing contraindications, procedure details are described, stressing the need for correct scheduling and not moving during the examination. The structured report including BI-RADS registered categories and further actions after a breast MRI examination are discussed. Breast MRI is a very sensitive modality, significantly improving screening in high-risk women. It also has a role in clinical diagnosis, problem solving, and staging, impacting on patient management. However, it is not a perfect test, and occasionally breast cancers can be missed. Therefore, clinical and other imaging findings (from mammography/ultrasound) should also be considered. Conversely, MRI may detect lesions not visible on other imaging modalities turning out to be benign (false positives). These risks should be discussed with women before a breast MRI is requested/performed. Because breast MRI drawbacks depend upon the indication for the examination, basic information for the most important breast MRI indications is presented. Seventeen notes and five frequently asked questions formulated for use as direct communication to women are provided. The text was reviewed by Europa Donna-The European Breast Cancer Coalition to ensure that it can be easily understood by women undergoing MRI. (orig.)
[en] The author shows that an energy of 30 nano- Joule is triggering a biologic reaction, therefore a threshold for radiation induced damage cannot be defined. Experiments concerning the sensitivity of metabolism with respect to external impacts are described, including gradients of parameters.
[en] As described before, some studies dealing with coordination chemistry of sugar phosphates are available but no analogous complexes of Zn"I"I have been investigated yet. The primary goal of this work is, therefore, to fill this gap. In order to stay close to the active sites of enzymes such as class-II-aldolase, the simple metal fragment Zn"I"I(dien) is used. NMR spectroscopy is used primarily as analytical method since it enables the investigation of both complex equilibria in solution and pH dependence of metal-binding sites. Since this approach is challenging due to the fast metal-ligand exchange and the absence of CIS values, it is necessary to improve the significance of NMR data collected from sugar-phosphate complexes with Zn"I"I. Hence, further experiments are performed with molecules similar to sugar phosphates such as reducing and methylated sugars or polyols. Beside NMR spectroscopy, crystal-structure analysis will be used to get more detailed information about the binding pattern of the complexes. Additionally, sugar-phosphate complexes of Pd"I"I are investigated. Further experiments are conducted, on the one hand, to synthesise more sugarphosphate complexes with ReVON2 fragments, and, on the other hand, to grow crystals confirming the theory about mixed sugar-core-phosphate chelation.
[en] Based on experimental observations, it is nowadays assumed that a large component of the matter content in the universe is comprised of so-called cold dark matter. Furthermore, latest measurements of the temperature fluctuations of the cosmic microwave background provided an estimation of the dark matter relic density at a measurement error of one percent (concerning the experimental 1σ-error). The lightest neutralino χ 0_1, a particle which subsumes under the phenomenologically interesting category of weakly interacting massive particles, is a viable dark matter candidate for many supersymmetric (SUSY) models whose relic density Ω_χ _0__1 happens to lie quite naturally within the experimentally favored ballpark of dark matter. The high experimental precision can be used to constrain the SUSY parameter space to its cosmologically favored regions and to pin down phenomenologically interesting scenarios. However, to actually benefit from this progress on the experimental side it is also mandatory to minimize the theoretical uncertainties. An important quantity within the calculation of the neutralino relic density is the thermally averaged sum over different annihilation and coannihilation cross sections of the neutralino and further supersymmetric particles. It is now assumed and also partly proven that these cross sections can be subject to large loop corrections which can even shift the associated Ω_χ _0__1 by a factor larger than the current experimental error. However, most of these corrections are yet unknown. In this thesis, we calculate higher-order corrections for some of the most important (co)annihilation channels both within the framework of the R-parity conserving Minimal Supersymmetric Standard Model (MSSM) and investigate their impact on the final neutralino relic density Ω_χ _0__1. More precisely, this work provides the full O(α_s) corrections of supersymmetric quantum chromodynamics (SUSY-QCD) to the (co)annihilation channels of neutralinos and charginos into quarks as well as of squark (co)annihilation into electro weak final states. Therefore, we give a detailed description of the DR/on-shell renormalization scheme used in the context of associated UV-divergences. On top of that, we introduce the methods of ''phase-space slicing'' and ''dipole subtraction'', which are needed to evaluate infrared and collinear singular cross sections numerically. Furthermore, we describe additional non-perturbative effects, socalled Coulomb corrections, which turn out to alter the cross sections connected to the (co)annihilation of squarks sizeably. We have implemented all of the corrections aforementioned into a software package called DM rate at NLO, which provides the full O(α_s) corrections for a broad variety of relevant (co)annihilation channels. DM rate at NLO therefore presents a significant extension of currently available public tools, which so far only allow for a calculation of (co)annihilation channels at the effective Born level. Concerning the numerical analysis of our results, for each of the above two (co)annihilation classes, we choose three different scenarios to present the impact of our higher-order corrections on the final neutralino relic density Ω_χ _0__1. We find that both classes of cross sections, namely for the (co)annihilation of neutralinos and charginos as well as for the squark (co)annihilation, yield sizeable corrections to the final Ω_χ _0__1, which can be much larger than the current experimental uncertainty. Hence, this work confirms the relevance of higher-order corrections for a high precision estimation of the neutralino relic density and, moreover, allows for a distinct insight into the interplay of the different, partly exotic, (co)annihilation channels in the calculation of the final Ω_χ _0__1.
[en] This thesis deals with practical security aspects of quantum key distribution (QKD) systems. At the heart of the theoretical model of any QKD system lies a quantum-mechanical security proof that guarantees perfect secrecy of messages - based on certain assumptions. However, in practice, deviations between the theoretical model and the physical implementation could be exploited by an attacker to break the security of the system. These deviations may arise from technical limitations and operational imperfections in the physical implementation and/or unrealistic assumptions and insufficient constraints in the theoretical model. In this thesis, we experimentally investigate in depth several such deviations. We demonstrate the resultant vulnerabilities via proof-of-principle attacks on a commercial QKD system from ID Quantique. We also propose countermeasures against the investigated loopholes to secure both existing and future QKD implementations.