Showing papers by "Technical University of Dortmund published in 2009"
TL;DR: In this article, benchmark configurations for quantitative validation and comparison of incompressible interfacial flow codes, which model two-dimensional bubbles rising in liquid columns, are proposed, and the benchmark quantities: circularity, center of mass, and mean rise velocity are defined and measured to monitor convergence toward a reference solution.
Abstract: Benchmark configurations for quantitative validation and comparison of incompressible interfacial flow codes, which model two-dimensional bubbles rising in liquid columns, are proposed. The benchmark quantities: circularity, center of mass, and mean rise velocity are defined and measured to monitor convergence toward a reference solution. Comprehensive studies are undertaken by three independent research groups, two representing Eulerian level set finite-element codes and one representing an arbitrary Lagrangian-Eulerian moving grid approach.
486 citations
TL;DR: In this article, the cutting edge rounding (CER) was introduced as a measure of sharpness/bluntness of uncoated carbide tools during drilling CFRP composite laminates.
Abstract: An evenly and smoothly distributed abrasion wear, observed along the entire cutting edge of an uncoated carbide drill bit in drilling CFRPs, is due to the highly abrasive nature of the carbon fibres. A very few researchers have only quoted this wear mode as being responsible for giving rise to the rounding of the cutting edge, or its bluntness. However, this wear feature has seldom been investigated, unlike the conventional flank wear in practice. This paper offers a new approach in unveiling and introducing the cutting edge rounding (CER) – a latent wear characteristic as a measure of sharpness/bluntness – of uncoated cemented carbide tools during drilling CFRP composite laminates. Four different types of drills (conventional and specialised) were tested to assess the applicability and relevance of this new wear feature. Mechanical loads (drilling thrust and torque) were recorded, and the hole entry and exit delamination were quantified. For the utilised tools, the accruing magnitude of CER was also recorded, in parallel with studying their conventional flank wear. Very appreciable correlations between the CER and the drilling loads, and also the quantitative delamination results are observed. Results reveal that this new wear type develops almost similarly for the selected tools and is practically independent of their respective conventional flank wear patterns. Moreover, a distinct, non-zero magnitude of the CER for a very fresh tool state may provide researchers with some lucid information in further studying the results during wear tests, more emphatically. The CER correlations with quantitative delamination results are noticed quite comparable to those of the conventional flank wear via statistical linear regression analyses.
414 citations
TL;DR: In this article, a systematic review on size effects in manufacturing of metallic components is presented, where the typology of size effects is explained, followed by a description of size effect on strength and tribology, and last three sections describe size effects on formability, forming processes and cutting processes.
381 citations
TL;DR: The results offer a caution as to the possibility of using endophytic fungi as alternate sources of plant secondary metabolite production, and further studies have been initiated on the analysis of the upstream metabolic intermediates to understand the steps at which the production of the metabolites in question is constrained.
Abstract: The pentacyclic quinoline alkaloid camptothecin (1) is a potent antineoplastic agent. Two of its analogues, 9-methoxycamptothecin (2) and 10-hydroxycamptothecin (3), exhibit similar potency but do not have the potential therapeutic drawbacks produced by unmodified 1. We have established methodology for the isolation and unequivocal identification and characterization of a novel endophytic fungus isolated from the inner bark of the medicinal plant Camptotheca acuminata, which produced 1-3 in rich mycological medium (Sabouraud dextrose broth), under shake-flask fermentation conditions. The fungus was identified by its morphology and authenticated by ITS analysis (ITS1 and ITS2 regions and the intervening 5.8S rDNA region). Camptothecin (1) and its analogues were identified by 1H NMR spectroscopy and LC-HRMS and confirmed by comparison with authentic standards. The production pattern of the metabolites over seven successive subculture generations of this endophyte was studied. A sharp attenuation in the production of 1 and 2 was observed from the first- through to the seventh-generation subculture. Therefore, these results offer a caution as to the possibility of using endophytic fungi as alternate sources of plant secondary metabolite production. Further studies have been initiated on the analysis of the upstream metabolic intermediates to understand the steps at which the production of the metabolites in question is constrained.
346 citations
01 Apr 2009-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this paper, the Digital Optical Modules (DOMs) are used to detect, digitize and timestamp the signals from optical Cherenkov-radiation photons at the South Pole.
Abstract: IceCube is a km-scale neutrino observatory under construction at the South Pole with sensors both in the deep ice (InIce) and on the surface (IceTop). The sensors, called Digital Optical Modules (DOMs). detect, digitize and timestamp the signals from optical Cherenkov-radiation photons. The DOM Main Board (MB) data acquisition subsystem is connected to the central DAQ in the IceCube Laboratory (ICL) by a single twisted copper wire-pair and transmits packetized data on demand. Time calibration is maintained throughout the array by regular transmission to the DOMs of precisely timed analog signals, synchronized to a central GPS-disciplined clock. The design goals and consequent features, functional capabilities, and initial performance of the DOM MB, and the operation of a combined array of DOMs as a system, are described here. Experience with the first InIce strings and the IceTop stations indicates that the system design and performance goals have been achieved. (c) 2009 Elsevier B.V. All rights reserved.
325 citations
01 Jan 2009
TL;DR: The Experteninterview is eines der am haufigsten eingesetzten Verfahren in der empirischen Sozialforschung.
Abstract: Das Experteninterview ist eines der am haufigsten eingesetzten Verfahren in der empirischen Sozialforschung. Es kommt sowohl als eigenstandiges Verfahren als auch im Rahmen einer Methodentriangulation zur Anwendung. Bereiche, in denen besonders haufig von Experteninterviews Gebrauch gemacht wird, sind die industriesoziologische Forschung, die Organisationsforschung, die Bildungsforschung und die Politikforschung. Lange Zeit erfolgten die Durchfuhrung und die Auswertung von Experteninterviews in Gestalt eines methodologischen Pragmatismus. Die Forschungspraxis war von einer gewissen “Hemdsarmeligkeit“ gepragt. Der Haufigkeit der Anwendung des Verfahrens korrespondierte keine methodologische Reflexion, die sich um eine Bestimmung der Besonderheiten des Experteninterviews gegenuber anderen Interviewverfahren bemuhte. Die Folge ist eine gewisse “Unubersichtlichkeit und Uneinheitlichkeit in der Auffassung und Darstellung von Experteninterviews“ (Mieg/Brunner 2004: 199; ahnlich Bogner/Menz 2002a: 20). Dies gilt gleichermasen fur die deutsche wie die internationale Forschungslandschaft.
322 citations
TL;DR: This Review is aimed at reviving myrcene as a renewable compound suitable for sustainable chemistry in the area of fine chemicals, and the versatility of the unsaturated C(10)-hydrocarbon myrcenes, leading to products with several different areas of application, is pointed out.
Abstract: Currently, a shift towards chemical products derived from renewable, biological feedstocks is observed more and more. However, substantial differences with traditional feedstocks, such as their “hyperfunctionalization,” ethical problems caused by competition with foods, and problems with a constant qualitative/quantitative availability of the natural products, occasionally complicate the large-scale market entry of renewable resources. In this context the vast family of terpenes is often not taken into consideration, although the terpenes have been known for hundreds of years as components of essential oils obtained from leaves, flowers, and fruits of many plants. The simple acyclic monoterpenes, particularly the industrially available myrcene, provide a classical chemistry similar to unsaturated hydrocarbons already known from oil and gas. Hence, this Review is aimed at reviving myrcene as a renewable compound suitable for sustainable chemistry in the area of fine chemicals. The versatility of the unsaturated C10-hydrocarbon myrcene, leading to products with several different areas of application, is pointed out.
284 citations
TL;DR: Isolation, identification and characterization of an endophytic fungus from Juniperus communis L. Horstmann, as a novel producer of deoxypodophyllotoxin and its in vitro antimicrobial assay.
Abstract: Aims: Isolation, identification and characterization of an endophytic fungus from Juniperus communis L. Horstmann, as a novel producer of deoxypodophyllotoxin and its in vitro antimicrobial assay.
Methods and Results: The methodology for the isolation, identification and characterization of a novel endophytic fungus from the twigs of the J. communis L. Horstmann plant, which specifically and consistently produces deoxypodophyllotoxin, was unequivocally established. The fungus was identified as Aspergillus fumigatus Fresenius by molecular, morphological and physiological methods. Deoxypodophyllotoxin was identified and quantified by high-resolution LC-MS, LC-MS2 and LC-MS3. The antimicrobial efficacy of the fungal deoxypodophyllotoxin against a panel of pathogenic bacteria was established.
Conclusions: The production of deoxypodophyllotoxin (found in the host) by the cultured endophyte is an enigmatic observation. It demonstrates the transfer of gene(s) for such accumulation by horizontal means from the host plant to its endophytic counterpart. It would be interesting to further study the deoxypodophyllotoxin production and regulation by the cultured endophyte in J. communis and in axenic cultures.
Significance and Impact of the Study: This endophyte is a potential handle for scientific and commercial exploitation. Although the current accumulation of deoxypodophyllotoxin by the endophyte is not very high, it could be scaled-up to provide adequate production to satisfy new drug development and clinical needs. However, further refined precursor-feeding and mass-balance studies are required to result in the consistent and dependable production.
255 citations
TL;DR: It is shown that hepatocyte dedifferentiation is a reversible consequence of a specific signaling network constellation triggered by the extracellular matrix and is reversible when Akt and/or ERK1/2 signaling pathways are antagonized.
238 citations
TL;DR: A comprehensive overview of the application of Markov models in the research field of offline handwriting recognition, covering both the widely used hidden Markov model and the less complex Markov-chain or n-gram models is provided.
Abstract: Since their first inception more than half a century ago, automatic reading systems have evolved substantially, thereby showing impressive performance on machine-printed text. The recognition of handwriting can, however, still be considered an open research problem due to its substantial variation in appearance. With the introduction of Markovian models to the field, a promising modeling and recognition paradigm was established for automatic offline handwriting recognition. However, so far, no standard procedures for building Markov-model-based recognizers could be established though trends toward unified approaches can be identified. It is therefore the goal of this survey to provide a comprehensive overview of the application of Markov models in the research field of offline handwriting recognition, covering both the widely used hidden Markov models and the less complex Markov-chain or n-gram models. First, we will introduce the typical architecture of a Markov-model-based offline handwriting recognition system and make the reader familiar with the essential theoretical concepts behind Markovian models. Then, we will give a thorough review of the solutions proposed in the literature for the open problems how to apply Markov-model-based approaches to automatic offline handwriting recognition.
229 citations
TL;DR: The naturally split α subunit of the DNA polymerase III (DnaE) intein from Nostoc punctiforme PCC73102 (Npu) is studied using purified proteins and an apparent first‐order rate constant of 1.1 ± 0.2 s−1 is determined, which represents the highest rate reported for the protein trans‐splicing reaction so far.
TL;DR: An analysis of gel permeation and UV absorption data indicates that the wastewater DOC is largely polymeric, and at 12 mg/L the concentration of its subunits must be near 100 microM with epsilon(254 nm) approximately 3000 M(-1) cm(-1).
Abstract: For the prediction of the elimination efficiency of micropollutants from wastewater by ozone, the ozone rate constants of the micropollutants and the kinetics of the reaction of ozone with wastewater must be known. The latter is multiphasic with k = 0.071 (mg DOC)(-1) s(-1) for the first mg/L ozone (at a DOC of 7.2 mg/L) followed by 0.011 (mg DOC)(-1) s(-1) the next 5 mg/L ozone and the k = 0.0019 (mg DOC)(-1) s(-1) for subsequent 4 mg/L ozone as determined by stopped-flow and batch-quench methods. An analysis of gel permeation and UV absorption data indicates that the wastewater DOC is largely polymeric, and at 12 mg/L the concentration of its subunits must be near 100 microM with epsilon(254 nm) approximately 3000 M(-1) cm(-1). The *OH radical yield as determined by the tertiary butanol assay is approximately 13%. From its dose dependence, it follows that new *OH-generating sites are formed during ozonation. The *OH scavenging capacity of the wastewater DOC has been determined at 3 x 10(4) (mg DOC)(-1) s(-1). The contribution of bicarbonate to the OH scavenging capacity is small in comparison, approximately 10% of DOC. Simulations indicate that at 5 mg/L ozone only the most reactive (k > 3 x 10(30 M(-1) s(-1)) micropollutants are fully eliminated but at 10 mg/L ozone the slow ozone decay starts to contribute and even the much less reactive ones (k = 300 M(-1) s(-1)) are oxidized (25% remaining).
01 Mar 2009
TL;DR: An overview over the structural principles of lithium organics and their Lewis base coordinated complexes in the solid state is given and the structure-reactivity relationship is depicted by means of the reactivity of the Lewis bases towards intramolecular decomposition reactions with the organolithium compound.
Abstract: Organolithium chemistry! An overview of the structure formation principles and the strong structure–reactivity relationship of lithium organics is given. By means of the commonly used lithium bases the deaggregation of the oligomeric parent structures to small adducts is presented (see examples) and compared to the related chemistry of lithiosilanes.
The structure–reactivity relationship is an important feature of organolithium compounds. The knowledge of the structure of reactive species is crucial for the elucidation of reaction mechanisms and the understanding of observed selectivities. This concept article gives an overview over the structural principles of lithium organics and their Lewis base coordinated complexes in the solid state. The transition from the oligomeric parent structures to smaller adducts, such as dimers and monomers, as well as special degrees of aggregation is presented. Besides the commonly used alkyllithium compounds, a short overview over the structural principles of the higher homologous silyllithium compounds is given. Moreover, the structure–reactivity relationship is depicted by means of the reactivity of the Lewis bases towards intramolecular decomposition reactions with the organolithium compound. Selected examples confirm the importance of structure elucidation for the understanding of mechanistic pathways and selectivities.
TL;DR: In this article, the dynamical parton distributions of the nucleon generated radiatively from valence-like positive input distributions at an optimally chosen low resolution scale are compared with the standard NNLO distributions generated from positive input distribution at some fixed and higher resolution scale.
Abstract: Utilizing recent deep inelastic scattering measurements $({\ensuremath{\sigma}}_{r},{F}_{2,3,L})$ and data on hadronic dilepton production we determine at next-to-next-to-leading order (NNLO) (3-loop) of QCD the dynamical parton distributions of the nucleon generated radiatively from valencelike positive input distributions at an optimally chosen low resolution scale (${Q}_{0}^{2}l1\text{ }\text{ }{\mathrm{GeV}}^{2}$). These are compared with ``standard'' NNLO distributions generated from positive input distributions at some fixed and higher resolution scale (${Q}_{0}^{2}g1\text{ }\text{ }{\mathrm{GeV}}^{2}$). Although the NNLO corrections imply in both approaches an improved value of ${\ensuremath{\chi}}^{2}$, typically ${\ensuremath{\chi}}_{\mathrm{NNLO}}^{2}\ensuremath{\simeq}0.9{\ensuremath{\chi}}_{\mathrm{NLO}}^{2}$, present deep inelastic scattering data are still not sufficiently accurate to distinguish between NLO results and the minute NNLO effects of a few percent, despite the fact that the dynamical NNLO uncertainties are somewhat smaller than the NLO ones and both are, as expected, smaller than those of their standard counterparts. The dynamical predictions for ${F}_{L}(x,{Q}^{2})$ become perturbatively stable already at ${Q}^{2}=2--3\text{ }\text{ }{\mathrm{GeV}}^{2}$ where precision measurements could even delineate NNLO effects in the very small-$x$ region. This is in contrast to the common standard approach but NNLO/NLO differences are here less distinguishable due to the larger $1\ensuremath{\sigma}$ uncertainty bands. Within the dynamical approach we obtain ${\ensuremath{\alpha}}_{s}({M}_{Z}^{2})=0.1124\ifmmode\pm\else\textpm\fi{}0.0020$, whereas the somewhat less constrained standard fit gives ${\ensuremath{\alpha}}_{s}({M}_{Z}^{2})=0.1158\ifmmode\pm\else\textpm\fi{}0.0035$.
TL;DR: A variety of biofilm reactor configurations have been explored for productive catalysis and some reactors have been operated continuously for months, which all facilitate continuous processing.
TL;DR: Scaffold Hunter is described, a highly interactive computer-based tool for navigation in chemical space that fosters intuitive recognition of complex structural relationships associated with bioactivity and provides proof of concept for pyruvate kinase.
Abstract: We describe Scaffold Hunter, a highly interactive computer-based tool for navigation in chemical space that fosters intuitive recognition of complex structural relationships associated with bioactivity. The program reads compound structures and bioactivity data, generates compound scaffolds, correlates them in a hierarchical tree-like arrangement, and annotates them with bioactivity. Brachiation along tree branches from structurally complex to simple scaffolds allows identification of new ligand types. We provide proof of concept for pyruvate kinase.
TL;DR: A measurement technique using a streak camera is demonstrated that overcomes this limitation and provides a record of the arrival times of individual photons and identifies regimes of dynamical anti-bunching of photons in agreement with the predictions of a microscopic theory that includes semiconductor-specific effects.
Abstract: Coherent light emission in lasers is reflected in a change of the photon statistics. Here Wiersig et al. demonstrate a streak camera technique with sufficient time resolution to probe the dynamical evolution of correlations between individual photon emission events. This work may lead to novel quantum optical studies addressing the dynamics of correlation functions of light. Lasers are recognized for coherent light emission, the onset of which is reflected in a change in photon statistics; but, until now, attempts to directly measure correlations in the individual photon emission events of semiconductor lasers have been unsuccessful. By using a streak camera technique with sufficient time resolution, the dynamical evolution of correlations between individual photon emission events is now demonstrated. Lasers are recognized for coherent light emission, the onset of which is reflected in a change in the photon statistics1. For many years, attempts have been made to directly measure correlations in the individual photon emission events of semiconductor lasers2,3. Previously, the temporal decay of these correlations below or at the lasing threshold was considerably faster than could be measured with the time resolution provided by the Hanbury Brown/Twiss measurement set-up4 used. Here we demonstrate a measurement technique using a streak camera that overcomes this limitation and provides a record of the arrival times of individual photons. This allows us to investigate the dynamical evolution of correlations between the individual photon emission events. We apply our studies to micropillar lasers5 with semiconductor quantum dots2,3,6,7,8 as the active material, operating in the regime of cavity quantum electrodynamics9. For laser resonators with a low cavity quality factor, Q, a smooth transition from photon bunching to uncorrelated emission with increasing pumping is observed; for high-Q resonators, we see a non-monotonic dependence around the threshold where quantum light emission can occur. We identify regimes of dynamical anti-bunching of photons in agreement with the predictions of a microscopic theory that includes semiconductor-specific effects.
TL;DR: In this article, pressure is used as a physical-chemical parameter for studying the physicochemical and phase behavior of lipid self-assembly and the effect of other additives such as ions, cholesterol, and anaesthetics.
Abstract: Besides temperature, hydrostatic pressure has been used as a physical-chemical parameter for studying the energetics and phase behavior of membrane systems. First we review some theoretical aspects of lipid self-assembly. Then, the temperature and pressure dependent structure and phase behavior of lipid bilayers, differing in chain configuration, headgroup structure and composition as revealed by using thermodynamic, spectroscopic and scattering experiments is discussed. We also report on the lateral organization of phase-separated lipid membranes and model raft mixtures as well as the influence of peptide and protein incorporation on membrane structure and dynamics upon pressurization. Also the effect of other additives, such as ions, cholesterol, and anaesthetics is discussed. Furthermore, we introduce pressure as a kinetic variable. Applying the pressure-jump relaxation technique in combination with time-resolved synchrotron X-ray diffraction, the kinetics of various lipid phase transformations was investigated. Finally, also new data on pressure effects on membrane mimetics, such as surfactants and microemulsions, are presented.
TL;DR: This work investigated the applicability of the thermodynamic model perturbed-chain statistical associating fluid theory (PC-SAFT) to correlate and to predict the solubility of exemplary five typical drug substances and intermediates in pure solvents and solvent mixtures.
TL;DR: In this article, the authors used tip-enhanced Raman scattering (TERS) to characterize single viruses at a molecular level, and reported the first time about TERS spectra of a tobacco mosaic virus, showing the great capability of this technique.
Abstract: The development of fast identification techniques of viruses is an ongoing important research topic. Conventional virus detection and identification is generally based on various different microbiological methods. However, these techniques are not suitable for the analysis of single virus particles. Therefore, our goal is to establish tip-enhanced Raman scattering (TERS), providing vibrational spectroscopic information with a spatial resolution less than 50 nm, to characterize single viruses at a molecular level. Here we report, to the best of our knowledge for the first time, about TERS spectra of a tobacco mosaic virus, showing the great capability of this technique. However, the application of the TERS technique for a rapid and direct detection of different species of single viruses is under development, which is useful for a wide range of analytical fields. Copyright © 2008 John Wiley & Sons, Ltd.
TL;DR: In this article, the axial mass parameter M A was extracted from the measured quasi-elastic neutrino cross section, which is consistent with the AXial mass values recalculated from the antineutrino X 2 shape analysis of the high purity sample of ν μ 2 track events, but has smaller systematic error.
Abstract: We have studied the muon neutrino and antineutrino quasi-elastic (QEL) scattering reactions ( ν μ n→ μ - p and bar{ν }_{μ}ptoμ+n ) using a set of experimental data collected by the NOMAD Collaboration. We have performed measurements of the cross-section of these processes on a nuclear target (mainly carbon) normalizing it to the total ν μ ( bar{ν}_{μ} ) charged-current cross section. The results for the flux-averaged QEL cross sections in the (anti)neutrino energy interval 3-100 GeV are < σ_{qel}rangle_{ν_{μ}}=(0.92±0.02(stat)±0.06(syst))×10^{-38} cm2 and <σ_{qel}rangle_{bar{ν}_{μ}}=(0.81±0.05(stat)±0.09(syst))×10^{-38} cm2 for neutrino and antineutrino, respectively. The axial mass parameter M A was extracted from the measured quasi-elastic neutrino cross section. The corresponding result is M A =1.05±0.02(stat)±0.06(syst) GeV. It is consistent with the axial mass values recalculated from the antineutrino cross section and extracted from the pure Q 2 shape analysis of the high purity sample of ν μ quasi-elastic 2-track events, but has smaller systematic error and should be quoted as the main result of this work. Our measured M A is found to be in good agreement with the world average value obtained in previous deuterium filled bubble chamber experiments. The NOMAD measurement of M A is lower than those recently published by K2K and MiniBooNE Collaborations. However, within the large errors quoted by these experiments on M A , these results are compatible with the more precise NOMAD value.
TL;DR: In this article, the authors thank the Ministry of Science and Education (MEC) (Project CTQ2007-67532-C02-01) for financial support of their research.
TL;DR: In this paper, the authors demonstrate ultrafast optical rotations of spins about arbitrary axes on a picosecond timescale using laser pulses as control fields, using an ensemble of quantum-dot electron spins focused into a small number of precession modes about a magnetic field by periodic optical pumping.
Abstract: The spin state of electrons trapped in a quantum dot only lasts a few microseconds. Before this information is lost, it is useful to controllably rotate the spin as many times as possible. Laser pulses can now rotate electron spins in an ensemble of quantum dots in just a few picoseconds. Coherent manipulation of quantum bits (qubits) on timescales much shorter than the coherence time1,2 is a key prerequisite for quantum information processing. Electron spins in quantum dots are particularly attractive for implementations of qubits, and efficient optical methods for initialization and readout of spins have been developed in recent years3,4. Spin coherence times in the microsecond range have been demonstrated5. Therefore, spin control by picosecond optical pulses would be highly desirable so that a large number of spin rotations could be carried out while coherence is maintained. A major remaining challenge is demonstration of such rotations with high fidelity. Here, we use an ensemble of quantum-dot electron spins focused into a small number of precession modes about a magnetic field by periodic optical pumping. We demonstrate ultrafast optical rotations of spins about arbitrary axes on a picosecond timescale using laser pulses as control fields.
TL;DR: In this paper, the authors search for evidence of a light scalar boson in the radiative decays of the 2S and 3S resonances and find no evidence for such processes in the mass range 0.212 and 9.3 GeV, respectively.
Abstract: We search for evidence of a light scalar boson in the radiative decays of the {Upsilon}(2S) and {Upsilon}(3S) resonances: {Upsilon}(2S, 3S) {yields} {gamma}A{sup 0}, A{sup 0} {yields} {mu}{sup +}{mu}{sup -}. Such a particle appears in extensions of the Standaard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. We find no evidence for such processes in the mass range 0.212 {<=} m{sub A{sup 0}} {<=} 9.3 GeV in the samples of 99 x 10{sup 6} {Upsilon}(2S) and 122 x 10{sup 6} {Upsilon}(3S) decays collected by the BABAR detector at the PEP-II B-factory and set stringent upper limits on the effective coupling of the b quark to the A{sup 0}. We also limit the dimuon branching fraction of the {eta}{sub b} meson: {Beta}({eta}{sub b} {yields} {mu}{sup +}{mu}{sup -}) < 0.9% at 90% confidence level.
TL;DR: This work describes how to consider the S-metric as a special case of a more general geometric problem called Klee's measure problem (KMP), an algorithm that exists with runtime O(n log n nd2 log n), for n points of d 3 dimensions.
Abstract: The dominated hypervolume (or S-metric) is a commonly accepted quality measure for comparing approximations of Pareto fronts generated by multi-objective optimizers. Since optimizers exist, namely evolutionary algorithms, that use the S-metric internally several times per iteration, a fast determination of the S-metric value is of essential importance. This work describes how to consider the S-metric as a special case of a more general geometric problem called Klee's measure problem (KMP). For KMP, an algorithm exists with runtime O(n log n + nd/2 log n), for n points of d ≥ 3 dimensions. This complex algorithm is adapted to the special case of calculating the S-metric. Conceptual simplifications realize the algorithm without complex data structures and establish an upper bound of O(nd/2 log n) for the S-metric calculation for d ≥ 3. The performance of the new algorithm is studied in comparison to another state of the art algorithm on a set of academic test functions.
TL;DR: This work presents the first runtime analysis of an ACO algorithm, which transfers many rigorous results with respect to the runtime of a simple evolutionary algorithm to the authors' algorithm, and examines the choice of the evaporation factor, a crucial parameter in ACO algorithms, in detail.
Abstract: Ant Colony Optimization (ACO) has become quite popular in recent years. In contrast to many successful applications, the theoretical foundation of this randomized search heuristic is rather weak. Building up such a theory is demanded to understand how these heuristics work as well as to come up with better algorithms for certain problems. Up to now, only convergence results have been achieved showing that optimal solutions can be obtained in finite time. We present the first runtime analysis of an ACO algorithm, which transfers many rigorous results with respect to the runtime of a simple evolutionary algorithm to our algorithm. Moreover, we examine the choice of the evaporation factor, a crucial parameter in ACO algorithms, in detail. By deriving new lower bounds on the tails of sums of independent Poisson trials, we determine the effect of the evaporation factor almost completely and prove a phase transition from exponential to polynomial runtime.
TL;DR: In this paper, the results of a search for Z(4430)^- decay to J/Ψ π- or Ψ(2S)π^- in B(^-.0)→ J/√ π^-K^(0.+) and B^(-.1×10^(-5) at 95% confidence level were reported.
Abstract: We report the results of a search for Z(4430)^- decay to J/Ψ π^- or Ψ(2S)π^- in B(^-.0)→ J/Ψ π^-K^(0.+) and B^(-.0) → Ψ(2S)π^-K^(0.+) decays. The data were collected with the BABAR detector at the SLAC PEP-II asymmetric-energy e^+e^- collider operating at center-of-mass energy 10.58 GeV, and the sample corresponds to an integrated luminosity of 413 fb^(-1). Each K π^- mass distribution exhibits clear K^*(892) and K_2^*(1430) signals, and the efficiency-corrected spectrum is well described by a superposition of the associated Breit-Wigner intensity distributions, together with an S-wave contribution obtained from the LASS I=1/2 K π^- scattering amplitude measurements. Each K π^- angular distribution varies significantly in structure with K π^- mass, and is represented in terms of low-order Legendre polynomial moments. We find that each J/Ψ π^- or Ψ (2S)π^- mass distribution is well described by the reflection of the measured K π^- mass and angular distribution structures. We see no significant evidence for a Z(4430)^- signal for any of the processes investigated, neither in the total J/Ψ π^- or Ψ(2S) π^- mass distribution, nor in the corresponding distributions for the regions of K π- mass for which observation of the Z(4430)^- signal was reported. We obtain branching-fraction upper limits [script B](B^- → Z^-[overline K]^0,Z^- → J/Ψ π^-)<1.5×10^(-5), [script B](B^0 → Z^-K^+,Z^- → J/Ψ π^-)<0.4×10^(-5), [script B](B → Z-[overline K]0,Z → Ψ(2S)π-)<4.7×10-5, and [script B](B^0 → Z^-K^+,Z^- → Ψ(2S)π^-)<3.1×10^(-5) at 95% confidence level, where the Z(4430)- mass and width have been fixed to the reported central values
TL;DR: Thymol and carvacrol displayed a concentration dependent antioxidant capacity, whilst gamma-terpinene which lacks a phenolic group did not show any antioxidant capacity in the trolox equivalent antioxidant capacity (TEAC) assay.
TL;DR: In this paper, the influence of aluminium powder and chemical additives on the properties of the microstructure of the hardened cement matrices were investigated by using petrographic microscopy as well as scanning electron microscopy.