Analysis of the kinetics for the H2 + - \frac{1}{2}O2 ⇌ H2O reaction on a hot Pt surface in the pressure range 0.10–10 Torr

The H₂ + O₂ ⇌ H₂O reaction on platinum at 700 and 1300 K has been studied. A stagnation flow geometry was used with a gas mixture of H₂ and O₂ at pressures between 0.10 and 10 Torr. Comparing SHG results with simulations using different reaction parameters, it was concluded that , and . LIF measurements showed an ambiguity in the choice of main water-producing channel. Both hydrogen addition with low sticking coefficients and hydroxyl disproportionation with high sticking coefficients are plausible. This revised version was published online in July 2006 with corrections to the Cover Date.     

Analyzing facial expressions for virtual conferencing

The authors present a model-based algorithm that estimates 3D motion and facial expressions from 2D image sequences showing head and shoulder scenes typical of video telephone and teleconferencing applications     

Tuning HP1α chromodomain selectivity for di- and trimethyllysine

Histone lysine methylation is a critical marker for controlling gene expression. The position and extent of methylation (mono-, di-, or tri-) controls the binding of effector proteins that determine whether the associated DNA is expressed or not. Dysregulation of histone protein methylation has been associated with a number of types of cancer, and development of inhibitors for the effector proteins is becoming an active area of research. For this reason, understanding the mechanism by which effector proteins obtain selectivity for the different methylation states of lysine is of great interest. To this end, we have performed mutation studies on the Drosophila HP1α chromodomain, which binds H3K9Me(2) and H3K9Me(3) with approximately equal affinities. The selectivity of HP1α chromodomain for H3K9Me(3) over H3K9Me(2) was investigated by mutating E52 to remove or weaken the hydrogen bond to K9Me(2) while maintaining affinity for K9Me(3,) including E52F, E52I, E52V, E52D, an E52Q. The E52Q mutant exhibited the greatest degree of selectivity for KMe3, with 3.5-fold weaker binding to the dimethylated peptide (K(D) =52 μM) compared to the trimethylated peptide (K(D) =15 μM). These studies provide insight into the role of electrostatic interactions and hydrogen bonding in the differentiation of methylation states and have implications regarding the evolutionary pressure for selectivity in this protein-protein interaction. Moreover, the information from this study may help guide inhibitor development for this class of proteins.     

Irradiation for bronchial carcinoma: reasons for failure. I. Analysis of local control as a function of dose, time, and fractionation

Radiation therapy is the only potentially curative form of therapy for patients with carcinoma of the lung who are not surgical candidates. Previous studies have evaluated response by evaluating survival. Evaluation of local control of disease is essential if one is to understand and modify therapeutic approaches in an effort to increase survival. Clinical data are presented on 197 patients with primary epithelial tumors of the lung. An analysis of local control data is presented using the concept of nomial standard dose (NSD). If local failure is to occur, it is manifest by 15 months. Survival is affected by the ability or inability to achieve local control. Above a dose of 1450 ret, no correlation between increasing ret dose and increasing local control is observed.     

Towards Systematic Business Model Innovation: Lessons from Product Innovation Management

Although business model innovations are decisive for a company's long‐term success or failure, they are still poorly understood compared to product innovations. Thus, their execution is imperfectly supported, and their organizational accountability is insufficiently regulated. In this paper, we systematically investigate similarities and differences between product and business model innovation to assess the potential of transferring insights and best practices. Therefore, we condense key findings of product innovation management into a framework as a basis for the analysis of 11 current cases of business model innovation. This paper intends to contribute to a better understanding of the options that exist for business model innovation. We derive implications for an improved management of business model innovation based on the cases analysed. For the innovation process and its organizational anchoring, we disclose potential benefits of a more structured and holistic approach.     

Quantum games

Abstract

In these lecture notes we investigate the implications of the identification of strategies with quantum operations in game theory beyond the results presented Eisert et al. (1999, Phys. Rev. Lett., 83, 3077). After introducing a general framework, we study quantum games with a classical analogue in order to flesh out the peculiarities of game theoretical settings in the quantum domain. Special emphasis is given to a detailed investigation of different sets of quantum strategies.     

Two-dimensional characterization of spatially entangled photon pairs

We characterize the entanglement in position and momentum of photon pairs generated in type-II parametric down-conversion. Coincidence maps of the photon positions in the near-field and far-field planes are observed in two transverse dimensions using scanning fiber probes. We estimate the covariance matrix of an effective two-mode system and apply criteria for entanglement based on covariance matrices to certify space–momentum entanglement. The role of higher-order spatial modes for observing spatial entanglement between the two photons is discussed.     

Monocyte chemotactic protein-1 as a potential biomarker for early anti-thrombotic therapy after ischemic stroke

Inflammation following ischemic brain injury is correlated with adverse outcome. Preclinical studies indicate that treatment with acetylsalicylic acid + extended-release dipyridamole (ASA + ER-DP) has anti-inflammatory and thereby neuroprotective effects by inhibition of monocyte chemotactic protein-1 (MCP-1) expression. We hypothesized that early treatment with ASA + ER-DP will reduce levels of MCP-1 also in patients with ischemic stroke. The EARLY trial randomized patients with ischemic stroke or TIA to either ASA + ER-DP treatment or ASA monotherapy within 24 h following the event. After 7 days, all patients were treated for up to 90 days with ASA + ER-DP. MCP-1 was determined from blood samples taken from 425 patients on admission and day 8. The change in MCP-1 from admission to day 8 did not differ between patients treated with ASA + ER-DP and ASA monotherapy (p > 0.05). Comparisons within MCP-1 baseline quartiles indicated that patients in the highest quartile (>217-973 pg/mL) showed improved outcome at 90 days if treated with ASA + ER-DP in comparison to treatment with ASA alone (p = 0.004). Our data does not provide any evidence that treatment with ASA + ER-DP lowers MCP-1 in acute stroke patients. However, MCP-1 may be a useful biomarker for deciding on early stroke therapy, as patients with high MCP-1 at baseline appear to benefit from early treatment with ASA + ER-DP.