Technical University of Dortmund

About: Technical University of Dortmund is a education organization based out in Dortmund, Nordrhein-Westfalen, Germany. It is known for research contribution in the topics: Context (language use) & Large Hadron Collider. The organization has 13028 authors who have published 27666 publications receiving 615557 citations. The organization is also known as: Dortmund University & University of Dortmund.

On the Accurate Identification of Active Constraints

Abstract: We consider nonlinear programs with inequality constraints, and we focus on the problem of identifying those constraints which will be active at an isolated local solution. The correct identification of active constraints is important from both a theoretical and a practical point of view. Such an identification removes the combinatorial aspect of the problem and locally reduces the inequality constrained minimization problem to an equality constrained problem which can be more easily dealt with. We present a new technique which identifies active constraints in a neighborhood of a solution and which requires neither complementary slackness nor uniqueness of the multipliers. We also present extensions to variational inequalities and numerical examples illustrating the identification technique.

Optical detection of the Aharonov-Bohm effect on a charged particle in a nanoscale quantum ring.

Abstract: We study spectroscopically the current produced by a charged particle moving in a nanosize semiconductor quantum ring subject to a perpendicular magnetic field. Several Aharonov-Bohm oscillations are observed in the emission of a charged exciton confined in a single ring structure. The magnetic field period of the oscillations correlates well with the size of the rings.

Single-cell analysis in biotechnology, systems biology, and biocatalysis.

Abstract: Single-cell analysis (SCA) has been increasingly recognized as the key technology for the elucidation of cellular functions, which are not accessible from bulk measurements on the population level. Thus far, SCA has been achieved by miniaturization of established engineering concepts to match the dimensions of a single cell. However, SCA requires procedures beyond the classical approach of upstream processing, fermentation, and downstream processing because the biological system itself defines the technical demands. This review characterizes currently available microfluidics and microreactors for invasive (i.e., chemical) and noninvasive (i.e., biological) SCA. We describe the recent SCA omics approaches as tools for systems biology and discuss the role of SCA in genomics, transcriptomics, proteomics, metabolomics, and fluxomics. Furthermore, we discuss applications of SCA for biocatalysis and metabolic engineering as well as its potential for bioprocess optimization. Finally, we define present and future...

Measurements of branching fractions, rate asymmetries, and angular distributions in the rare decays B→Kℓ^+ℓ^- and B→K^*ℓ^+ℓ^-

Abstract: We present measurements of the flavor-changing neutral current decays B -> K center dot(+)center dot(-) and B -> K-*center dot(+)center dot(-), where center dot(+)center dot(-) is either an e(+)e(-) or mu(+)mu(-) pair. The data sample comprises 229x10(6) Upsilon(4S)-> B (B) over bar decays collected with the BABAR detector at the PEP-II e(+)e(-) storage ring. Flavor-changing neutral current decays are highly suppressed in the standard model and their predicted properties could be significantly modified by new physics at the electroweak scale. We measure the branching fractions B(B -> K center dot(+)center dot(-))=(0.34 +/- 0.07 +/- 0.02)x10(-6), B(B -> K-*center dot(+)center dot(-))=(0.78(-0.17)(+0.19)+/- 0.11)x10(-6), the direct CP asymmetries of these decays, and the relative abundances of decays to electrons and muons. For two regions in center dot(+)center dot(-) mass, above and below m(J/psi), we measure partial branching fractions and the forward-backward angular asymmetry of the lepton pair. In these same regions we also measure the K-* longitudinal polarization in B -> K-*center dot(+)center dot(-) decays. Upper limits are obtained for the lepton-flavor-violating decays B -> Ke mu and B -> K(*)e mu. All measurements are consistent with standard model expectations.