Global dynamics of the Horava-Lifshitz cosmological model in a non-flat universe with non-zero cosmological constant

When the cosmological constant is non-zero the dynamics of the cosmological model based on Horava-Lifshitz gravity in a non-flat universe is characterized by using the qualitative theory of differential equations.Comment: 60 pages, 34 figure

Global dynamics of the Hořava-Lifshitz cosmological system

Using the qualitative theory of the differential equations we describe the global dynamics of the cosmological model based on Hořava-Lifshitz gravity in a Friedmann-Lemaître-Robertson-Walker space time with zero curvature and without the cosmological constant term

Approximate Analytical Periodic Solutions to the Restricted Three-Body Problem with Perturbation, Oblateness, Radiation and Varying Mass

Against the background of a restricted three-body problem consisting of a supergiant eclipsing binary system, the two primaries are composed of a pair of bright oblate stars whose mass changes with time. The zero-velocity surface and curve of the problem are numerically studied to describe the third body's motion area, and the corresponding five libration points are obtained. Moreover,theeffectofsmallperturbations,Coriolisandcentrifugalforces,radiativepressure,andthe oblateness and mass parameters of the two primaries on the third body's dynamic behavior is discussed through the bifurcation diagram. Furthermore, the second- and third-order approximate analytical periodic solutions around the collinear solution point L3 in two-dimensional plane and three-dimensional spaces are presented by using the Lindstedt-Poincaré perturbation method

Evaluation of the differences of myocardial fibers between acute and chronic myocardial infarction: Application of diffusion tensor magnetic resonance imaging in a rhesus monkey model

Objective: To understand microstructural changes after myocardial infarction (MI), we evaluated myocardial fibers of rhesus monkeys during acute or chronic MI, and identified the differences of myocardial fibers between acute and chronic MI. Materials and Methods: Six fixed hearts of rhesus monkeys with left anterior descending coronary artery ligation for 1 hour or 84 days were scanned by diffusion tensor magnetic resonance imaging (MRI) to measure apparent diffusion coefficient (ADC), fractional anisotropy (FA) and helix angle (HA). Results: Comparing with acute MI monkeys (FA: 0.59 +/- 0.02; ADC: 5.0 +/- 0.6 x 10(-4) mm(2)/s; HA: 94.5 +/- 4.4 degrees), chronic MI monkeys showed remarkably decreased FA value (0.26 +/- 0.03), increased ADC value (7.8 +/- 0.8 x 10(-4)mm(2)/s), decreased HA transmural range (49.5 +/- 4.6 degrees) and serious defects on endocardium in infarcted regions. The HA in infarcted regions shifted to more components of negative left-handed helix in chronic MI monkeys (-38.3 +/- 5.0 degrees-11.2 +/- 4.3 degrees) than in acute MI monkeys (-41.4 +/- 5.1 degrees-53.1 +/- 3.7 degrees), but the HA in remote regions shifted to more components of positive right-handed helix in chronic MI monkeys (-43.8 +/- 2.7 degrees-66.5 +/- 4.9 degrees) than in acute MI monkeys (-59.5 +/- 3.4 degrees-64.9 +/- 4.3 degrees). Conclusion: Diffusion tensor MRI method helps to quantify differences of mechanical microstructure and water diffusion of myocardial fibers between acute and chronic MI monkey's models.National Natural Science Foundation of China [81130027, 81301196]SCI(E)[email protected]