Results 71 to 80 of about 4,930,166 (237)

The Cyclicity of Period Annulus of Degenerate Quadratic Hamiltonian System with Elliptic Segment

, 2000
AMS (MOS). Mathematics Subject Classification. 58F21, 34C05, 58F27, 58F30.We study the cyclicity of period annuli (or annulus) for general degenerate quadratic Hamiltonian systems with an elliptic segment or a saddle loop, under quadratic perturbations.
Li, Chengzhi, Chow, Shui-Nee, Yi, Yingfei   +2 more
core   +1 more source

Early comparison of one-year outcomes after aortic mechanical vs. biological valve replacement in Chinese patients with small aortic annulus

Journal of Cardiothoracic Surgery
Background This study compares short-term clinical and hemodynamic outcomes of AVR using mechanical versus bovine pericardial valves in patients with a small aortic annulus (≤ 21 mm) and evaluates the feasibility and safety of AVR in this population ...
Yu Sun, Yang Gao, Wen Xiao, Zimo Wang, Yonglei Liu, Xiao Wang, Laichun Song   +6 more
doaj   +1 more source

THE CYCLICITY OF THE PERIOD ANNULUS OF TWO CLASSES OF CUBIC ISOCHRONOUS SYSTEMS

Journal of Applied Analysis & Computation, 2013
In this paper, we investigate the cyclicity of the period annulus of two classes of cubic isochronous systems.By using the Chebyshev criterion, we prove that the two systems have respectively at most three and four limit cycles produced fromthe period annulus around the isochronous center under cubic perturbations.
null Yi Shao, null Kuilin Wu
openaire   +1 more source

Functional comparison of EncB and EncC cargo proteins in iron storage within the Myxococcus xanthus encapsulin

FEBS Letters, EarlyView.
Encapsulins are protein nanocompartments that play an important role in iron storage. In the Myxococcus xanthus encapsulin system, two cargo proteins called EncB and EncC contribute to iron mineralization. Here, we show that EncB and EncC generate iron‐containing minerals with distinct chemical compositions, suggesting that the composition of stored ...
Harry B. McDowell, Thomas Walther, Egbert Hoiczyk   +2 more
wiley   +1 more source

Hilbert's 16th problem on a period annulus and Nash space of arcs

, 2018
This article introduces an algebro-geometric setting for the space of bifurcation functions involved in the local Hilbert's 16th problem on a period annulus.
Gavrilov, Lubomir, Xiao, Dongmei, Françoise, Jean-Pierre   +2 more
core   +4 more sources

A characterization of almost periodic homeomorphisms on the 2-sphere and the annulus

General Topology and its Applications, 1978
AbstractThe purpose of this paper is to show that every almost periodic homeomorphism of the 2-sphere or the annulus onto itself is topologically equivalent to either a standard rotation or a standard reflection or the composition of a standard reflection with a standard rotation of these spaces.
openaire   +1 more source

Limit Cycles Bifurcating from a Period Annulus in Continuous Piecewise Linear Differential Systems with Three Zones

, 2017
We study a class of planar continuous piecewise linear vector fields with three zones. Using the Poincaré map and some techniques for proving the existence of limit cycles for smooth differential systems, we prove that this class admits at least two ...
Weber F. Pereira, Maurício Firmino Silva Lima, Claudio Pessoa, Pereira, Weber F. [UNESP], Silva Lima, Mauricio Firmino, Pessoa, Claudio [UNESP]   +5 more
core   +1 more source

Structures of mycobacterial 3‐methylcrotonyl‐CoA carboxylase reveal carrier‐domain translocation between catalytic sites

FEBS Letters, EarlyView.
Mycobacterial 3‐methylcrotonyl‐CoA carboxylase uses a mobile biotin‐carrying domain to shuttle a carboxyl group between two catalytic sites, enabling carboxylation of 3‐methylcrotonyl‐CoA during leucine breakdown. Cryo‐electron microscopy captures the carrier at both sites and reveals an inward loop movement that may prevent futile rebinding to the ...
Ajit Yadav, Bogdan I. Florea, Sebastian Geibel   +2 more
wiley   +1 more source

Computation of families of periodic orbits and bifurcations around a massive annulus

Astrophysics and Space Science, 2011
This paper studies the main features of the dynamics around a planar annular disk. It is addressed an appropriated closed expression of the gravitational potential of a massive disk, which overcomes the difficulties found in previous works in this matter concerning its numerical treatment.
Tresaco, E., Elipe, A., Riaguas, A.
openaire   +3 more sources

Chiral separation of chloroalkanes with the chromatographic column onboard Martian rovers

FEBS Letters, EarlyView.
Computer image of the Rosalind Franklin Rover of ESA's ExoMars mission. ExoMars is scheduled to land on planet Mars in Oxia Planum in 2029. This area represents an interesting spot to look for biosignatures. Investigations of ExoMars include measurement on molecular chirality. We show that chiral chloroalkanes, that have been identified on Mars, can be
Asma Merzougui, Agnes Banreti, Armelle L. Ernst, Guillaume Leseigneur, Uwe J. Meierhenrich   +4 more
wiley   +1 more source