Radiative corrections to the neutral-current Drell-Yan process in the Standard Model and its minimal supersymmetric extension

An adequate description of the neutral-current Drell-Yan process at the Tevatron and the LHC, in particular, requires the inclusion of electroweak radiative corrections. We extend earlier work in this direction in various ways. First, we define and numerically compare different methods to describe the Z-boson resonance including next-to-leading order electroweak corrections; moreover, we provide explicit analytical expressions for those. Second, we pay particular attention to contributions from photon-photon and photon-quark collisions, which involve photons in the initial state, and work out how their impact can be enhanced by selection cuts. Third, we supplement the O(\alpha) corrections by universal electroweak effects of higher order, such as universal two-loop contributions from \Delta\alpha and \Delta\rho, and the leading two-loop corrections in the high-energy Sudakov regime as well as multi-photon radiation off muons in the structure-function approach. Finally, we present results on the complete next-to-leading order electroweak and QCD corrections within the minimal supersymmetric extension of the Standard Model.Comment: 57 pages, latex, 19 figures, 7 tables; photon PDF factorization changed; minor corrections; version to appear in JHE

A current assessment of the Hamburg rules

Trade has been booming. The WTO ( World Trade Organisation) estimated that world trade in goods grew 8 % in volume terms last year, this being four times the growth of world GDP (Gross Domestic Products). During the 1990s international trade has grown far faster than world output, showing that national economies are becoming more closely linked. Foreign direct investment, another gauge of international economies integration, is also soaring: last year, estimated the United Nations Conference on Trade and Development, cross border investment increased by 40%, to $315 billion

Collective treatment of the giant resonances in spherical nuclei

In a collective treatment the energies of the giant resonances are given by the boundary conditions at the nuclear surface, which is subject to vibration in spherical nuclei. The general form of the coupling between these two collective motions is given by angular-momentum and parity conservation. The coupling constants are completely determined within the hydrodynamical model. In the present treatment the influence of the surface vibrations on the total photon-absorption cross section is calculated. It turns out that in most of the spherical nuclei this interaction leads to a pronounced structure in the cross section. The agreement with the experiments in medium-heavy nuclei is striking; many of the experimental characteristics are reproduced by the present calculations. In some nuclei, however, there seem to be indications of single-particle excitations which are not yet contained in this work

Modulation of Tight Junction Structure and Function by Kinases and Phosphatases Targeting Occludin

Tight junctions (TJs) typically represent the most apical contacts in epithelial and endothelial cell layers where they play an essential role in the separation of extracellular or luminal spaces from underlying tissues in the body. Depending on the protein composition, TJs define the barrier characteristics and in addition maintain cell polarity. Two major families of integral membrane proteins form the typical TJ strand network, the tight junction-associated MARVEL protein (TAMP) family members occludin, tricellulin, and MarvelD3 as well as a specific set of claudins. Occludin was the first identified member of these tetraspanins and is now widely accepted as a regulator of TJ assembly and function. Therefore, occludin itself has to be tightly regulated. Phosphorylation of occludin appears to be of central importance in this context. Here we want to summarize current knowledge on the kinases and phosphatases directly modifying occludin, and their role in the regulation of TJ structure, function, and dynamics

Characterization of Hamamatsu 64-channel TSV SiPMs

The Hamamatsu UV-light enhanced 64-channel SiPM array of the newest generation (S13361-3050AS-08) has been examined for the purpose of being used for the Silicon Elementary Cell Add-on (SiECA) of the EUSO-SPB balloon experiment. Characterization measurements have been performed with the newly installed Single Photon Calibration Stand at KIT (SPOCK). The results of the characterization measurements including the breakdown voltage, the gain, the PDE, the dark-count rate and the crosstalk probability of all 64 SiPM channels are presented. Additional measurements of the SiPM sensitivity to photons with wavelengths lower than 400nm show an improved PDE for small wavelengths compared to the SiPM array S12642-0808PA-50, which was also investigated for comparison. The response dynamics have been investigated for low numbers of incoming photons. Temperature dependent measurements of the gain, the PDE, the dark-count rate and the crosstalk probability have been performed for one channel of the SiPM array.Comment: Accepted for publication in Nuclear Instruments and Methods

Déficit de atención y rendimiento académico de los estudiantes de Secundaria de la I.E. Héroes de Sangrar Cullhuay - Canta

El fundamento de la presente investigación de tesis fue determinar la relación entre Déficit de Atención y Rendimiento Académico en los estudiantes de secundaria de la Institución Educativa Héroes de Sangrar Cullhuay – Canta UGEL 12. El diseño de la investigación utilizado fue descriptivo – correlacional, pues tiene como propósito medir la relación entre las dos variables de estudio: Déficit de atención y rendimiento académico en la Institución Educativa Héroes de Sangrar Cullhuay – Canta. La muestra estuvo constituida por 40 estudiantes de 1° a 5° año de secundaria, a quienes se les aplicó un cuestionario para evaluar el Déficit de Atención y rendimiento académico. Los hallazgos indicaron que no existe relación significativa entre Déficit de Atención y Rendimiento Académico (p > .05); sin embargo, se encontraron dos relaciones significativas por dimensiones: (p < .05) y (p < .01)

Proceedings of the 3rd IUI Workshop on Interacting with Smart Objects

These are the Proceedings of the 3rd IUI Workshop on Interacting with Smart Objects. Objects that we use in our everyday life are expanding their restricted interaction capabilities and provide functionalities that go far beyond their original functionality. They feature computing capabilities and are thus able to capture information, process and store it and interact with their environments, turning them into smart objects