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What is a nullcline? 

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A nullcline is a graphical representation used to understand the behavior of nonlinear systems. It characterizes the points where the rate of change of one variable is zero while the other variable is held constant. Nullclines are commonly used in the study of predator-prey models , neuron models , genetic toggle switches , and FitzHugh-Nagumo oscillators . They provide insights into the steady-state distribution and firing patterns of these systems. In the context of genome analysis, null models are used to identify over- and under-represented sequence motifs. Generating accurate null models for coding sequences is challenging due to the unique constraints imposed by protein coding sequences. However, a method based on the principle of maximum entropy has been developed to generate unbiased random sequences with specified amino acid and GC content .

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Journal Article•DOI
A nullcline-based control strategy for PWL-shaped oscillators
Paolo Arena, Luca Patané, Angelo Giuseppe Spinosa 
01 Jul 2019-Nonlinear Dynamics
9 Citations
A nullcline is a curve in a phase portrait where the derivative of one variable is zero, indicating a steady state or equilibrium point.
Journal Article•DOI
Analog/Digital Multiplierless Implementations for Nullcline-Characteristics-Based Piecewise Linear Hindmarsh-Rose Neuron Model
Jianming Cai, Han Bao, Mo Chen, Quan Wei Xu, B. Bao 
01 Jul 2022-IEEE Transactions on Circuits and Systems I-regular Papers
15 Citations
A nullcline is a curve in a phase space where the derivative of a variable is zero. It represents the equilibrium points of a dynamical system.
Open access•Proceedings Article•DOI
Understanding the discrete genetic toggle switch phenomena using a discrete ‘nullcline’ construct inspired by the Markov chain tree theorem
Andreas Petrides, Glenn Vinnicombe 
01 Dec 2017
5 Citations
Nullclines are used to characterize and understand the behavior of low-dimensional nonlinear deterministic systems, but they are not a good predictor for discrete state stochastic systems.
Journal Article•DOI
A nullcline approach to global stability in discrete-time predator–prey models
Azmy S. Ackleh, Paul L. Salceanu, Amy Veprauskas 
03 Aug 2021-Journal of Difference Equations and Applications
2 Citations
Nullclines are curves in a phase plane where the rate of change of one variable is zero, indicating equilibrium points in the system.

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What is the best molecules formation for shock nullification?5 answersThe best molecules for shock nullification have not been explicitly mentioned in the provided abstracts. However, some papers discuss the formation of molecules and particles in shock systems. Herzler et al. studied the formation of TiN molecules and particles in TiCl4/NH3/H2 systems using laser absorption spectroscopy. Tan et al. calculated the resonance energies of various explosives, indicating that lower resonance energy corresponds to higher shock sensitivity. These studies provide insights into the behavior of molecules under shock conditions, but do not specifically address the best molecules for shock nullification. Further research is needed to determine the most effective molecules for this purpose.
What is the null hypothesis?4 answersThe null hypothesis is a statement that asserts that there is no relationship between two variables or no difference between two groups. It is often used in statistical analysis to test the validity of research hypotheses in various fields, including molecular genetics and biology. The null hypothesis is typically compared to an alternative hypothesis, which suggests the presence of an effect or difference. In the testing process, if the observed results or p-value indicate that the null hypothesis is unlikely true, it is rejected in favor of the alternative hypothesis. The null hypothesis is an important concept in scientific research as it helps researchers draw valid conclusions from their studies.
What is nothing?5 answersNothing is a sociologically neglected terrain that encompasses non-identification, non-participation, and non-presence. It is created and managed through meaningful social interaction, and is accomplished through active commission or passive omission. Four dimensions of negative social space - non-identity, inactivity, absence, and silence - contribute to the productive nature of nothing, as other symbolic objects are generated through the apprehension of phantoms, imaginaries, replacements, and alternatives. This sociological analysis reveals the significance of nothing in shaping social processes. Additionally, nothing is the formless flesh that surrounds every thing, serving as a ground or horizon that allows for connection and presence. It is the presence of an absence, the divine or spiritual element that enables the existence of things. This understanding of nothing challenges the fleshless interaction model and emphasizes the constitutive ground in between.
Why less than 0.05 reject the null hypothesis?3 answersThe significance level of 0.05 is commonly used to reject the null hypothesis in statistical hypothesis testing. However, there is controversy surrounding this practice. The traditional null hypothesis significance testing (NHST) was never intended for clinical significance to be inferred from statistical significance. The American Statistical Association has stated that p-values do not provide a good measure of evidence for a hypothesis and recommend stating the exact p-value along with effect size and confidence intervals. The prevalence of true effects is not generally known, and the false discovery rate can be high, especially when using p-values close to 0.05. Lowering the alpha level to 0.005 has been proposed as a way to combat the replication crisis in psychology, as findings with p-values close to 0.05 represent insufficient empirical evidence. In summary, the use of p < 0.05 to reject the null hypothesis is based on historical convention, but there are concerns about its validity and the high false discovery rate associated with it.
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