Results 31 to 40 of about 279,696 (263)
Eigenvalue Characterization of a System of Difference Equations [PDF]
Nonlinear Oscillations, 2004 We consider the system of difference equations $$u_i (k) = \lambda \mathop \sum \limits_{\ell = 0}^N g_i (k,\ell )P_i (\ell ,u_1 (\ell ),u_2 (\ell ),...,u_n (\ell )), k \in \{ 0,1,...,T\} , 1 \leqslant i \leqslant n,$$ where λ > 0 and T ≥ N ≥ 0. Our aim is to determine the values of λ for which the above system has a constant-sign solution.
Agarwal, R.P. +2 more
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The role and implications of mammalian cellular circadian entrainment
FEBS Letters, EarlyView.At their most fundamental level, mammalian circadian rhythms occur inside every individual cell. To tell the correct time, cells must align (or ‘entrain’) their circadian rhythm to the external environment. In this review, we highlight how cells entrain to the major circadian cues of light, feeding and temperature, and the implications this has for our
Priya Crosby
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Invariants for Difference Equations and Systems of Difference Equations of Rational Form
Journal of Mathematical Analysis and Applications, 1997 The author consideres the system of difference equations \[ x_{n+1} = \frac{a_n y_n + A}{x_{n-1}}, \qquad y_{n+1} = \frac{b_n x_n + A}{y_{n-1}}, n = 0, 1,\dots\tag{1} \] where the coefficients \(\{a_n\}\) and \(\{b_n\}\) are periodic sequences of positive numbers of period 2 and \(A\) is a positive constant. Some invariants for system (1) are presented.
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Crosstalk between the ribosome quality control‐associated E3 ubiquitin ligases LTN1 and RNF10
FEBS Letters, EarlyView.Loss of the E3 ligase LTN1, the ubiquitin‐like modifier UFM1, or the deubiquitinating enzyme UFSP2 disrupts endoplasmic reticulum–ribosome quality control (ER‐RQC), a pathway that removes stalled ribosomes and faulty proteins. This disruption may trigger a compensatory response to ER‐RQC defects, including increased expression of the E3 ligase RNF10 ...
Yuxi Huang +8 more
wiley +1 more source
Perturbations of Nonlinear Systems of Difference Equations
Journal of Mathematical Analysis and Applications, 1996 Sufficient conditions in order to ensure that the perturbed equation \[ y(n+1)= f(n,y(n))+ g(n,y(n)) \] inherits its stability from the equation \[ x(n+1)= f(n,x(n)), \] are given.
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Protein pyrophosphorylation by inositol pyrophosphates — detection, function, and regulation
FEBS Letters, EarlyView.Protein pyrophosphorylation is an unusual signaling mechanism that was discovered two decades ago. It can be driven by inositol pyrophosphate messengers and influences various cellular processes. Herein, we summarize the research progress and challenges of this field, covering pathways found to be regulated by this posttranslational modification as ...
Sarah Lampe +3 more
wiley +1 more source
Time after time – circadian clocks through the lens of oscillator theory
FEBS Letters, EarlyView.Oscillator theory bridges physics and circadian biology. Damped oscillators require external drivers, while limit cycles emerge from delayed feedback and nonlinearities. Coupling enables tissue‐level coherence, and entrainment aligns internal clocks with environmental cues.
Marta del Olmo +2 more
wiley +1 more source
Solutions of the system ofmaximum difference equations
MANAS: Journal of Engineering, 2015 The behaviour and periodicity of the solutions of the following system of difference equations is examined (1) where the initial conditions are positive real numbers.
D. Şimşek, M. Eröz
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Symmetric nonlinear solvable system of difference equations
Electronic Journal of Qualitative Theory of Differential EquationsWe show the theoretical solvability of the system of difference equations $$x_{n+k}=\frac{y_{n+l}y_n-cd}{y_{n+l}+y_n-c-d},\quad y_{n+k}=\frac{x_{n+l}x_n-cd}{x_{n+l}+x_n-c-d},\quad n\in\mathbb{N}_0,$$ where $k\in\mathbb{N}$, $l\in\mathbb{N}_0 ...
Stevo Stevic +2 more
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Dynamics of a Higher-Order System of Difference Equations
Discrete Dynamics in Nature and Society, 2017 Consider the following system of difference equations: xn+1(i)=xn-m+1(i)/Ai∏j=0m-1xn-j(i+j+1)+αi, xn+1(i+m)=xn+1(i), x1-l(i+l)=ai,l, Ai+m=Ai, αi+m=αi, i,l=1,2,…,m; n=0,1,2,…, where m is a positive integer, Ai,αi, i=1,2,…,m, and the initial conditions ai ...
Qi Wang, Qinqin Zhang, Qirui Li
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