Pre-entry advertising, entry deterrence and multi-informational signaling

Advertising is commonly regarded as a strategic tool to increase demand and steal business from competitors. The present work studies the competitive effects of advertising in a two-period game with incomplete information about the opponent's cost structure. Bagwell and Ramey (1988) showed that deterring entry is possible by signaling lower costs even if the post-entry game is independent of the pre-entry advertising decision. Assuming that pre-entry advertising by an entrant affects the post-entry game, then the incumbent is forced to do more than in the Bagwell/Ramey case to deter entry; he needs to distort costs downwards more extensively. On the other hand, introductory advertising does not facilitate entry if the entrant learns from the signal that competition with the incumbent is unprofitable. In this case, the entrant abstains from entry after performing introductory advertisng. Furthermore, if the incumbent has private information on cost and advertising effectiveness, then he can deter entry by acting as if he had lower production costs and a better advertising effectiveness. In this scenario, entry deterrence is associated with overinvestment in advertising but not with limit pricing, which is a new prediction. The use of multi-informational signals, i.e. pooled information on more than one type of private information transferred by one signal, is methodologically a new development of the classical signaling game.advertising, entry deterrence, advertising effectiveness, pre-entry advertising, signaling

Pre-entry advertising, entry deterrence and multi-informational signaling

Advertising is commonly regarded as a strategic tool to increase demand and steal business from competitors. The present work studies the competitive effects of advertising in a two-period game with incomplete information about the opponent's cost structure. Bagwell and Ramey (1988) showed that deterring entry is possible by signaling lower costs even if the post-entry game is independent of the pre-entry advertising decision. Assuming that pre-entry advertising by an entrant affects the post-entry game, then the incumbent is forced to do more than in the Bagwell/Ramey case to deter entry; he needs to distort costs downwards more extensively. On the other hand, introductory advertising does not facilitate entry if the entrant learns from the signal that competition with the incumbent is unprofitable. In this case, the entrant abstains from entry after performing introductory advertisng. Furthermore, if the incumbent has private information on cost and advertising effectiveness, then he can deter entry by acting as if he had lower production costs and a better advertising effectiveness. In this scenario, entry deterrence is associated with overinvestment in advertising but not with limit pricing, which is a new prediction. The use of multi-informational signals, i.e. pooled information on more than one type of private information transferred by one signal, is methodologically a new development of the classical signaling game

Pre-entry advertising, entry deterrence and multi-informational signaling

Advertising is commonly regarded as a strategic tool to increase demand and steal business from competitors. The present work studies the competitive effects of advertising in a two-period game with incomplete information about the opponent's cost structure. Bagwell and Ramey (1988) showed that deterring entry is possible by signaling lower costs even if the post-entry game is independent of the pre-entry advertising decision. Assuming that pre-entry advertising by an entrant affects the post-entry game, then the incumbent is forced to do more than in the Bagwell/Ramey case to deter entry; he needs to distort costs downwards more extensively. On the other hand, introductory advertising does not facilitate entry if the entrant learns from the signal that competition with the incumbent is unprofitable. In this case, the entrant abstains from entry after performing introductory advertisng. Furthermore, if the incumbent has private information on cost and advertising effectiveness, then he can deter entry by acting as if he had lower production costs and a better advertising effectiveness. In this scenario, entry deterrence is associated with overinvestment in advertising but not with limit pricing, which is a new prediction. The use of multi-informational signals, i.e. pooled information on more than one type of private information transferred by one signal, is methodologically a new development of the classical signaling game

Wavelet Monte Carlo dynamics : a new algorithm for simulating the hydrodynamics of interacting Brownian particles

We develop a new algorithm for the Brownian dynamics of soft matter systems that evolves time by spatially correlated Monte Carlo moves. The algorithm uses vector wavelets as its basic moves and produces hydrodynamics in the low Reynolds number regime propagated according to the Oseen tensor. When small moves are removed the correlations closely approximate the Rotne-Prager tensor, itself widely used to correct for deficiencies in Oseen. We also include plane wave moves to provide the longest range correlations, which we detail for both infinite and periodic systems. The computational cost of the algorithm scales competitively with the number of particles simulated, N, scaling as N ln N in homogeneous systems and as N in dilute systems. In comparisons to established lattice Boltzmann and Brownian dynamics algorithms the wavelet method was found to be only a factor of order 1 times more expensive than the cheaper lattice Boltzmann algorithm in marginally semi-dilute simulations, while it is significantly faster than both algorithms at large N in dilute simulations. We also validate the algorithm by checking it reproduces the correct dynamics and equilibrium properties of simple single polymer systems, as well as verifying the effect of periodicity on the mobility tensor

Stereo vision and acuity tests within a virtual reality set-up

Dankert T, Heil D, Pfeiffer T. Stereo vision and acuity tests within a virtual reality set-up. In: Latoschik ME, Staadt O, Steinicke F, eds. Virtuelle und Erweiterte Realität - 10. Workshop der GI-Fachgruppe VR/AR. Shaker Verlag; 2013: 185-188.The provision of stereo images to facilitate depth perception by stereopsis is one key aspect of many Virtual Reality installations and there are many technical approaches to do so. However, differences in visual capabilities of the user and technical limitations of a specific set-up might restrict the spatial range in which stereopsis can be facilitated. In this paper, we transfer an existent test for stereo vision from the real world to a virtual environment and extend it to measure stereo acuity

Design of the Magnet System of the Neutron Decay Facility PERC

The PERC (Proton and Electron Radiation Channel) facility is currently under construction at the research reactor FRM II, Garching. It will serve as an intense and clean source of electrons and protons from neutron beta decay for precision studies. It aims to contribute to the determination of the Cabibbo-Kobayashi-Maskawa quark-mixing element $V_{ud}$ from neutron decay data and to search for new physics via new effective couplings. PERC's central component is a 12m long superconducting magnet system. It hosts an 8m long decay region in a uniform field. An additional high-field region selects the phase space of electrons and protons which can reach the detectors and largely improves systematic uncertainties. We discuss the design of the magnet system and the resulting properties of the magnetic field.Comment: Proceedings of the International Workshop on Particle Physics at Neutron Sources PPNS 2018, Grenoble, France, May 24-26, 201

Comparing methods of measuring sea-ice density in the East Antarctic

Remotely sensed derivation of sea-ice thickness requires sea·ice density. Sea-ice density was estimated with three techniques during the second Sea Ice Physics and Ecosystem eXperiment (SIPEX-II, September-November 2012, East Antarctica). The sea ice was first-year highly deformed, mean thickness 1.2 m with layers, consistent with rafting, and 6-7/10 columnar ice and 3/10 granular ice. Ice density was found to be lower than values (900-920 kg m⁻³ used previously to derive ice thickness, with columnar ice mean density of 870 kg m⁻³. At two different ice stations the mean density of the ice was 870 and 800 kg m⁻³, the lower density reflecting a high percentage of porous granular ice at the second station. Error estimates for mass/volume and liquid/solid water methods are presented. With 0.1 m long, 0.1 m core samples, the error on individual density estimates is 28 kg m⁻³. Errors are larger for smaller machined blocks. Errors increase to 46 kg m⁻³ if the liquid/solid volume method is used. The mass/volume method has a low bias due to brine drainage of at least 5%. Bulk densities estimated from ice and snow measurements along 100 m transects were high, and likely unrealistic as the assumption of isostatic balance is not suitable over these length scales in deformed ice

Predictive potential of angiopoietin-2 in a mCRC subpopulation treated with vanucizumab in the McCAVE trial

IntroductionAngiopoetin-2 (Ang-2) is a key mediator of tumour angiogenesis. When upregulated it is associated with tumour progression and poor prognosis. Anti-vascular endothelial growth factor (VEGF) therapy has been widely used in the treatment of metastatic colorectal cancer (mCRC). The potential benefit of combined inhibition of Ang-2 and VEGF-A in previously untreated patients with mCRC was evaluated in the phase II McCAVE study (NCT02141295), assessing vanucizumab versus bevacizumab (VEGF-A inhibitor), both in combination with mFOLFOX-6 (modified folinic acid [leucovorin], fluorouracil and oxaliplatin) chemotherapy. To date, there are no known predictors of outcome of anti-angiogenic treatment in patients with mCRC. In this exploratory analysis, we investigate potential predictive biomarkers in baseline samples from McCAVE participants.MethodsTumour tissue samples underwent immunohistochemistry staining for different biomarkers, including Ang-2. Biomarker densities were scored on the tissue images using dedicated machine learning algorithms. Ang-2 levels were additionally assessed in plasma. Patients were stratified by KRAS mutation status determined using next generation sequencing. Median progression-free survival (PFS) for each treatment group by biomarker and KRAS mutation was estimated using Kaplan–Meier plots. PFS hazard ratios (and 95% confidence intervals) were compared using Cox regression.ResultsOverall low tissue baseline levels of Ang-2 were associated with longer PFS, especially in patients with wild-type KRAS status. In addition, our analysis identified a new subgroup of patients with KRAS wild-type mCRC and high levels of Ang-2 in whom vanucizumab/mFOLFOX-6 prolonged PFS significantly (log-rank p=0.01) by ~5.5 months versus bevacizumab/mFOLFOX-6. Similar findings were seen in plasma samples.DiscussionThis analysis demonstrates that additional Ang-2 inhibition provided by vanucizumab shows a greater effect than single VEGF-A inhibition in this subpopulation. These data suggest that Ang-2 may be both a prognostic biomarker in mCRC and a predictive biomarker for vanucizumab in KRAS wild-type mCRC. Thus, this evidence can potentially support the establishment of more tailored treatment approaches for patients with mCRC

The MRN complex is transcriptionally regulated by MYCN during neural cell proliferation to control replication stress

The MRE11/RAD50/NBS1 (MRN) complex is a major sensor of DNA double strand breaks, whose role in controlling faithful DNA replication and preventing replication stress is also emerging. Inactivation of the MRN complex invariably leads to developmental and/or degenerative neuronal defects, the pathogenesis of which still remains poorly understood. In particular, NBS1 gene mutations are associated with microcephaly and strongly impaired cerebellar development, both in humans and in the mouse model. These phenotypes strikingly overlap those induced by inactivation of MYCN, an essential promoter of the expansion of neuronal stem and progenitor cells, suggesting that MYCN and the MRN complex might be connected on a unique pathway essential for the safe expansion of neuronal cells. Here, we show that MYCN transcriptionally controls the expression of each component of the MRN complex. By genetic and pharmacological inhibition of the MRN complex in a MYCN overexpression model and in the more physiological context of the Hedgehog-dependent expansion of primary cerebellar granule progenitor cells, we also show that the MRN complex is required for MYCN-dependent proliferation. Indeed, its inhibition resulted in DNA damage, activation of a DNA damage response, and cell death in a MYCN- and replication-dependent manner. Our data indicate the MRN complex is essential to restrain MYCN-induced replication stress during neural cell proliferation and support the hypothesis that replication-born DNA damage is responsible for the neuronal defects associated with MRN dysfunctions.Cell Death and Differentiation advance online publication, 12 June 2015; doi:10.1038/cdd.2015.81

Physics and Applications of Laser Diode Chaos

An overview of chaos in laser diodes is provided which surveys experimental achievements in the area and explains the theory behind the phenomenon. The fundamental physics underpinning this behaviour and also the opportunities for harnessing laser diode chaos for potential applications are discussed. The availability and ease of operation of laser diodes, in a wide range of configurations, make them a convenient test-bed for exploring basic aspects of nonlinear and chaotic dynamics. It also makes them attractive for practical tasks, such as chaos-based secure communications and random number generation. Avenues for future research and development of chaotic laser diodes are also identified.Comment: Published in Nature Photonic