scholarly journals On the stability of type II blowup for the 1-corotational energy-supercritical harmonic heat flow

2019 ◽  
Vol 12 (1) ◽  
pp. 113-187 ◽  
Author(s):  
Tej-eddine Ghoul ◽  
Slim Ibrahim ◽  
Van Tien Nguyen
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Dipankar Ghosh ◽  
Prasun K. Santra ◽  
Abdelalim A. Elsadany ◽  
Ghanshaym S. Mahapatra

Abstract This paper focusses on developing two species, where only prey species suffers by a contagious disease. We consider the logistic growth rate of the prey population. The interaction between susceptible prey and infected prey with predator is presumed to be ruled by Holling type II and I functional response, respectively. A healthy prey is infected when it comes in direct contact with infected prey, and we also assume that predator-dependent disease spreads within the system. This research reveals that the transmission of this predator-dependent disease can have critical repercussions for the shaping of prey–predator interactions. The solution of the model is examined in relation to survival, uniqueness and boundedness. The positivity, feasibility and the stability conditions of the fixed points of the system are analysed by applying the linearization method and the Jacobian matrix method.


2001 ◽  
Vol 16 (17) ◽  
pp. 3025-3040 ◽  
Author(s):  
P. SUNDELL

We construct Spin (p + 1, p + 1) covariant D p-brane bound states by using the fact that the potentials in the RR sector of toroidically compactified type II supergravity transform as a chiral spinor of the T duality group. As an application, we show the invariance of the zero-force condition for a probe D-brane under noncommutative deformations of the background, which gives a holographic proof of the stability of the corresponding field theory ground state under noncommutative deformations. We also identify the Spin (p + 1, p + 1) transformation laws by examining the covariance of the D-brane Lagrangians.


Author(s):  
Abhishek Kumar ◽  
Nilam

Abstract In this article, we propose and analyze a time-delayed susceptible–infected–recovered (SIR) mathematical model with nonlinear incidence rate and nonlinear treatment rate for the control of infectious diseases and epidemics. The incidence rate of infection is considered as Crowley–Martin functional type and the treatment rate is considered as Holling functional type II. The stability of the model is investigated for the disease-free equilibrium (DFE) and endemic equilibrium (EE) points. From the mathematical analysis of the model, we prove that the model is locally asymptotically stable for DFE when the basic reproduction number {R_0} is less than unity ({R_0} \lt 1) and unstable when {R_0} is greater than unity ({R_0} \gt 1) for time lag \tau \ge 0. The stability behavior of the model for DFE at {R_0} = 1 is investigated using Castillo-Chavez and Song theorem, which shows that the model exhibits forward bifurcation at {R_0} = 1. We investigate the stability of the EE for time lag \tau \ge 0. We also discussed the Hopf bifurcation of EE numerically. Global stability of the model equilibria is also discussed. Furthermore, the model has been simulated numerically to exemplify analytical studies.


Sensors ◽  
2019 ◽  
Vol 19 (8) ◽  
pp. 1907 ◽  
Author(s):  
Tetiana Manyk ◽  
Krystian Michalczewski ◽  
Krzysztof Murawski ◽  
Piotr Martyniuk ◽  
Jaroslaw Rutkowski

The InAs/InAsSb type-II superlattices (T2SLs) grown on a GaSb buffer layer and GaAs substrates were theoretically investigated. Due to the stability at high operating temperatures, T2SLs could be used for detectors operating in the longwave infrared (LWIR) range for different sensors to include, e.g., CH4 and C2H6 detection, which is very relevant for health condition monitoring. The theoretical calculations were carried out by the 8 × 8 k·p method. The estimated electrons and heavy holes probability distribution in a InAs/InAsSb superlattice (SL) shows that the wave function overlap increases while the thickness of the SL period decreases. The change in the effective masses for electrons and holes versus the SL period thickness for the kz-direction of the Brillouin zone is shown. The structures with a period lower than 15 nm are more optimal for the construction of LWIR detectors based on InAs/InAsSb SLs. The experimental results of InAs/InAsSb T2SLs energy bandgap were found to be comparable with the theoretical one. The proper fitting of theoretically calculated and experimentally measured spectral response characteristics in terms of a strain-balanced and unbalanced structures is shown.


2011 ◽  
Vol 19 (02) ◽  
pp. 281-297 ◽  
Author(s):  
B. MUKHOPADHYAY ◽  
R. BHATTACHARYYA

In the present paper, we study a prey–predator–pathogen model where the prey population suffer from an SI epidemic. The predator is assumed to exercise preferential predation. The prey preference mechanism ranges from predation only on the susceptible or only on the infective to proportional predation on both the prey types. The formulation maintains the native Holling type-II functional response in one hand and invokes prey switching on the other. We first describe stability and persistence results for the model without preference, which highlights the significance of some system parameters namely, predator mortality rate and predation pressure on the susceptible in shaping the system dynamics. Then we investigate the model with the preference mechanism, which shows the importance of the preference parameter (α) in controlling the stability and existence criteria of component populations. Our study reveals the existence of preference parameter ranges that (i) guarantees stable species coexistence (ii) exhibits rich dynamics in the form of oscillatory phenomena, point attractors and limit cycle attractors and (iii) causes possible extinction of the predators together with the susceptible prey. The ecological meaning of the corresponding ranges is also elaborated.


1988 ◽  
Vol 106 (1) ◽  
pp. 161-170 ◽  
Author(s):  
P D Benya ◽  
P D Brown ◽  
S R Padilla

Primary monolayers of rabbit articular chondrocytes synthesize high levels of type II collagen and proteoglycan. This capacity was used as a marker for the expression of the differentiated phenotype. Such cells were treated with 1 microgram/ml retinoic acid (RA) for 10 d to produce a modulated collagen phenotype devoid of type II and consisting of predominantly type I trimer and type III collagen. After transfer to secondary culture in the presence of RA, the stability of the RA-modulated phenotype was investigated by culture in the absence of RA. Little reexpression of type II collagen synthesis occurred in this period unless cultures were treated with 3 X 10(-6) M dihydrocytochalasin B to modify microfilament structures. Reexpression of the differentiated phenotype began between days 6-8 and was essentially complete by day 14. Substantial reexpression occurred by day 8 without a detectable increase in cell rounding. Colony formation, characteristic of primary chondrocytes, was infrequent even after reexpression was complete. These data suggest that the integrity of microfilament cytoskeletal structures can be a source of regulatory signals that mechanistically appear to be more proximal to phenotypic change than the overt changes in cell shape that accompany reexpression of subculture-modulated chondrocytes in agarose culture.


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