1,018 research outputs found
Symmetric Jacobians
This article is about polynomial maps with a certain symmetry and/or
antisymmetry in their Jacobians, and whether the Jacobian Conjecture is
satisfied for such maps, or whether it is sufficient to prove the Jacobian
Conjecture for such maps.
For instance, we show that it suffices to prove the Jacobian conjecture for
polynomial maps x + H over C such that JH satisfies all symmetries of the
square, where H is homogeneous of arbitrary degree d >= 3.Comment: 18 pages, minor corrections, grayscale eepic boxes have been replaced
by colorful tikz boxe
On the theory of Gordan-Noether on homogeneous forms with zero Hessian (Improved version)
We give a detailed proof for Gordan-Noether's results in "Ueber die
algebraischen Formen, deren Hesse'sche Determinante identisch verschwindet"
published in 1876 in Mathematische Annahlen. C. Lossen has written a paper in a
similar direction as the present paper, but did not provide a proof for every
result. In our paper, every result is proved. Furthermore, our paper is
independent of Lossen's paper and includes a considerable number of new
observations.
An earlier version of this paper has been printed in Proceedings of the
School of Science of Tokai University, Vol.49, Mar. 2014. In this version, a
serious error has been corrected and some new results have been added
DFAs and PFAs with Long Shortest Synchronizing Word Length
Contains fulltext :
176563.pdf (publisher's version ) (Closed access)
Contains fulltext :
176563pre.pdf (preprint version ) (Open Access
Comparison of different exoplanet mass detection limit methods using a sample of main-sequence intermediate-type stars
The radial velocity (RV) technique is a powerful tool for detecting
extrasolar planets and deriving mass detection limits that are useful for
constraining planet pulsations and formation models. Detection limit methods
must take into account the temporal distribution of power of various origins in
the stellar signal. These methods must also be able to be applied to large
samples of stellar RV time series We describe new methods for providing
detection limits. We compute the detection limits for a sample of ten main
sequence stars, which are of G-F-A type, in general active, and/or with
detected planets, and various properties. We use them to compare the
performances of these methods with those of two other methods used in the
litterature. We obtained detection limits in the 2-1000 day period range for
ten stars. Two of the proposed methods, based on the correlation between
periodograms and the power in the periodogram of the RV time series in specific
period ranges, are robust and represent a significant improvement compared to a
method based on the root mean square of the RV signal. We conclude that two of
the new methods (correlation-based method and local power analysis, i.e. LPA,
method) provide robust detection limits, which are better than those provided
by methods that do not take into account the temporal sampling.Comment: 18 pages, 15 figures Accepted in Astronomy & Astrophysic
Fab glycosylation of immunoglobulin G does not associate with improvement of rheumatoid arthritis during pregnancy
Background: Changes in immunoglobulin G (IgG) constant domain (Fc) glycosylation are associated with changes in rheumatoid arthritis (RA) disease activity in response to pregnancy. Here, we sought to determine whether the same holds true for variable domain (Fab) glycosylation. Methods: IgGs were captured from RA and control sera obtained before (RA only), during and after pregnancy, followed by Fc and Fab separation, glycan release, and mass spectrometric detection. In parallel,
Financial Decision-Making in Markets and Firms: A Behavioral Perspective
In its attempt to model financial markets and the behavior of firms, modern finance theory starts from a set of normatively appealing axioms about individual behavior. Specifically, people are said to be risk-averse expected utility maximizers and unbiased Bayesian forecasters, i.e., agents make rational choices based on rational expectations. The rational paradigm may be criticized, however, because (1) the assumptions are descriptively false and incomplete, and (2) the theory often lacks predictive power. One way to make progress is to characterize actual decision- making behavior. Efforts along these lines are made by behavioral economists and psychologists. This paper provides a selective review of recent work in behavioral finance. First, we ask why economists should be concerned with the psychology of decision-making. Next, we discuss a series of key behavioral concepts, e.g., people's well-known tendencies to give too much weight to vivid information and to show excessive self-confidence. The body of the paper illustrates the relevance of these concepts to important topics in investment theory and corporate finance. In each case, behavioral finance offers a new perspective on results that are anomalous within the standard approach.
Voedselveiligheid, ketens en toezicht op controle
This AFSG, RIKILT and LEI report reviews legislation and private quality control systems related to food safety. For the IKB Pigs case, it then investigates which legal requirements are also incorporated in this private regulation. The report further describes how compliance with this system is safeguarded in practice. Finally, in relation to 'Audit Monitoring', several conclusions and recommendations are made. In dit rapport van AFSG, RIKILT en LEI wordt een overzicht gegeven van de met het oog op voedselveiligheid relevante wet- en regelgeving en private kwaliteitsborgingsystemen. Vervolgens is voor de case IKB Varkens nagegaan welke wettelijke eisen ook in deze pri-vate regeling zijn opgenomen. Tevens is in beeld gebracht hoe de naleving van dit systeem in de praktijk wordt gewaarborgd. Ten slotte worden met het oog op 'Toezicht op Controle' enkele conclusies getrokken en aanbevelingen gedaan.Food Consumption/Nutrition/Food Safety,
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