Control of unstable steady states by time-delayed feedback methods

We show that time-delayed feedback methods, which have successfully been used to control unstable periodic ortbits, provide a tool to stabilize unstable steady states. We present an analytical investigation of the feedback scheme using the Lambert function and discuss effects of both a low-pass filter included in the control loop and non-zero latency times associated with the generation and injection of the feedback signal.Comment: 8 pages, 11 figure

Varieties of Limited Access Orders: The nexus between politics and economics in hybrid regimes

This article advances our understanding of differences in hybrid stability by going beyond existing regime typologies that separate the study of political institutions from the study of economic institutions. It combines the work of Douglass North, John Wallis, and Barry Weingast (NWW) on varieties of social orders with the literature on political and economic regime typologies and dynamics to understand hybrid regimes as Limited Access Orders (LAOs) that differ in the way dominant elites limit access to political and economic resources. Based on a measurement of political and economic access applied to seven post‐Soviet states, the article identifies four types of LAOs. Challenging NWW's claim, it shows that hybrid regimes can combine different degrees of political and economic access to sustain stability. Our typology allows to form theoretical expectations about the kinds of political and/or economic changes that will move different types of LAOs toward more openness or closure

4He experiments can serve as a database for determining the three-nucleon force

We report on microscopic calculations for the 4He compound system in the framework of the resonating group model employing realistic nucleon-nucleon and three nucleon forces. The resulting scattering phase shifts are compared to those of a comprehensive R-matrix analysis of all data in this system, which are available in numerical form. The agreement between calculation and analysis is in most cases very good. Adding three-nucleon forces yields in many cases large effects. For a few cases the new agreement is striking. We relate some differencies between calculation and analysis to specific data and discuss neccessary experiments to clarify the situation. From the results we conclude that the data of the 4He system might be well suited to determine the structure of the three-nucleon force.Comment: title changed,note added, format of figures changed, appearance of figures in black-and-white changed, Phys. Rev. C accepte

Monotonic properties of the shift and penetration factors

We study derivatives of the shift and penetration factors of collision theory with respect to energy, angular momentum, and charge. Definitive results for the signs of these derivatives are found for the repulsive Coulomb case. In particular, we find that the derivative of the shift factor with respect to energy is positive for the repulsive Coulomb case, a long anticipated but heretofore unproven result. These results are closely connected to the properties of the sum of squares of the regular and irregular Coulomb functions; we also present investigations of this quantity.Comment: 13 pages, 1 figur

The Effect of Low Levels of Diethylstilbestrol and Plant Estrogens Upon Performance of Fattening Lambs

The excellent feeding properties of good quality legume hay and certain vegetable oil meals have long been recognized by the livestock producer. The observed feeding values of these feedstuffs cannot be attributed entirely to their classical nutrient compositions. It has been long suspected that they contain unidentified .factors that are stimulatory to growth

Study of Restricted Diffusion in Wood

An NMR study of restricted diffusion of water in Douglas-fir wood was undertaken using the pulsed field gradient method. The measurements were performed at 25 C and at two different moisture contents. Analysis of the results shows that the restricted diffusion of water molecules in this sample can be adequately described using a restricted diffusion model that considers diffusion to occur between infinite planar barriers. Two different barrier separations were incorporated into the model in order to obtain a good correspondence between the calculated and experimental results. Excellent agreement exists between parameters deduced from the NMR measurements and known anatomical data

Factorization and Lie point symmetries of general Lienard-type equation in the complex plane

We present a variational approach to a general Lienard-type equation in order to linearize it and, as an example, the Van der Pol oscillator is discussed. The new equation which is almost linear is factorized. The point symmetries of the deformed equation are also discussed and the two-dimensional Lie algebraic generators are obtained

Human interactome of the influenza B virus NS1 protein

This work was partially supported by NIAID grant U19AI106754, and by CRIP (Center for Research in Influenza Pathogenesis), an NIAID funded Center of Excellence for Influenza Research and Surveillance (CEIRS, contract #HHSN272201400008C) to A. G-S. Work at the University of Zurich was supported by the Swiss National Science Foundation (grant 31003A_159993 to BGH).NS1 proteins of influenza A and B viruses share limited sequence homology, yet both are potent manipulators of host cell processes, particularly interferon (IFN) induction. Although many cellular partners are reported for A/NS1, only a few (e.g. PKR and ISG15) have been identified for B/NS1. Here, affinity-purification and mass spectrometry were used to expand the known host interactome of B/NS1. We identified 22 human proteins as new putative targets for B/NS1, validating several, including DHX9, ILF3, YBX1 and HNRNPC. Consistent with two RNA-binding domains in B/NS1, many of the identified factors bind RNA and some interact with B/NS1 in an RNA-dependent manner. Functional characterization of several B/NS1 interactors identified SNRNP200 as a potential positive regulator of host IFN responses, while ILF3 exhibited dual roles in both IFN induction and influenza B virus replication. These data provide a resource for future investigations into the mechanisms underpinning host cell modulation by influenza B virus NS1.Publisher PDFPeer reviewe