Noisy regression and classification with continuous multilayer networks

We investigate zero temperature Gibbs learning for two classes of unrealizable rules which play an important role in practical applications of multilayer neural networks with differentiable activation functions: classification problems and noisy regression problems. Considering one step of replica symmetry breaking, we surprisingly find that for sufficiently large training sets the stable state is replica symmetric even though the target rule is unrealizable. Further, the classification problem is shown to be formally equivalent to the noisy regression problem.Comment: 7 pages, including 2 figure

Starting jet flows in a three-dimensional channel with larynx-shaped constriction

A numerical model for the three-dimensional starting jet flow in a channel with a static larynx-shaped constriction is presented. Detailed resolution of this kind of jet flow is necessary in order to understand the complex coupling between flow and acoustics in the process of human phonation. The numerical model is based on the equation of continuity and the Navier-Stokes equations. The investigations are done with the open source CFD package OpenFOAM. Numerical simulations are performed for a square-sectioned channel geometry, which is constricted with a fixed shape conforming to the fully opened human glottis. Time-dependent inflow boundary conditions are applied in order to model transient glottal flow rates. The setup of the numerical simulations corresponds to the configuration of a model experiment in order to allow detailed validation. The numerical results are in good agreement with the experimental data, when the near-wall region in the glottal gap is adequately resolved by the numerical grid. The results illustrate the complex interactions between the jet flow and the surrounding vortices. © 2011 Elsevier Ltd

Boceprevir in combination with HIV protease inhibitors in patients with advanced fibrosis-altered drug-drug interactions?

In HIV/HCV co-infected patients improved treatment outcomes have been reported for the HCV protease inhibitors (PIs) boceprevir (BOC) and telaprevir (TVR), reaching SVR rates of up to 70% in pilot trials. Due to complex drug-drug-interactions triple therapy is substantially limited in HIV/HCV-coinfected individuals. Co-administration of BOC with the commonly available HIV PIs has been reported not only to decrease the level of BOC but also to lead to relevant decreases in the respective HIV PI. Here, we report on two patients who received BOC-containing HCV triple therapy in combination with a HIV PI. Patient 1 was on darunavir 800 mg/ritonavir 100 mg once-daily mono-therapy. Using FibroScan a liver stiffness of 34 kPa suggested liver cirrhosis prior to start of HCV triple therapy. At week 5 of HCV triple therapy darunavir trough concentration was measured in the reference range with 3777 ng/ml (reference trough concentration 2400–4600 ng/ml). HCV-RNA became negative at week 10 and HIV-RNA was below detection limit (<40 copies/ml) at all times. Patient 2 was on a simplified FTC qd and fos-amprenavir 700 mg/ritonavir 100 mg bid regimen. Liver disease had also progressed to liver cirrhosis, confirmed in FibroScan, with a liver stiffness of 32 kPa. At week 8 of HCV triple therapy fos-amprenavir trough level was measured in the normal reference range with 1699 ng/ml (reference trough concentration 750–2500 ng/ml). At week 11 HCV-RNA was <12 IU/ml and HIV viral load was below detection limit of <40 copies/ml at all times. Our clinical data suggest that in patients with advanced liver disease possibly drug levels of HIV PIs which are coadministered with BOC may be within the normal range. In order to better understand the true amount of drug interactions between BOC and commonly used HIV PIs in HIV/HCV-coinfected patients with more advanced liver fibrosis, urgently more PK studies are required to make HCV triple therapy accessible for a wider number of HIV/HCV-coinfected patients in desperate need of these drugs

Automated quantification of the impact of the wood-decay fungus Physisporinus vitreus on the cell wall structure of Norway spruce by tomographic microscopy

The visualization and the quantification of microscopic decay patterns are important for the study of the impact of wood-decay fungi in general, as well as for wood-decay fungi and microorganisms with possible applications in biotechnology. In the present work, a method was developed for the automated localization and quantification of microscopic cell wall elements (CWE) of Norway spruce wood such as bordered pits, intrinsic defects, hyphae or alterations induced by white-rot fungus Physisporinus vitreus using high-resolution X-ray computed tomographic microscopy. In addition to classical destructive wood anatomical methods such as light or laser scanning microscopy, this method allows for the first time to compute the properties (e.g., area, orientation and size distribution) of CWE of the tracheids in a sample. This is essential for modeling the influence of microscopic CWE on macroscopic properties such as wood strength and permeabilit

One-particle inclusive CP asymmetries

One-particle inclusive CP asymmetries in the decays of the type B -> D(*) X are considered in the framework of a QCD based method to calculate the rates for one-particle inclusive decays.Comment: Latex, 13 pages, 6 figures (eps). Analytical and numerical results unchanged, extended discussion of model assumptions and systematic uncertainties. Version to be published in Phys. Rev. D 62, 0960xx. Additional transparencies are available via the WWW at http://www-ttp.physik.uni-karlsruhe.de/Slides