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1.
J Comput Chem ; 40(2): 316-327, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30299560

RESUMO

Application of Alpha-oscillator theory to quantum electrodynamics (QED) solves the mystery (Feynman) of the double-slit phenomenon involved in the foundation of quantum mechanics (QM). Even if with the same initial condition given, different spots on the screen can be predicted deterministically with no introduction of hidden variables. The interference pattern is similar to, but cannot be reproduced quantitatively by, that of the QM wave function, contrary to many-years-anticipation: a new prediction, awaiting experimental test over and above the Bohr-Einstein gedanken experiment. The general proof has already been published in Ref. [3a] and the concrete numerical algorithm of the extended normal mode technique for concrete trajectory of one electron in Ref. [3b]. In this article, (1) the new "interpretation" of the QED wave function is given in section "Interpretation of Wave Function in QED": the QED wave function used in the extended normal mode technique gives probability density distribution function of the initial values of trajectories. Moreover, (2) for the sake of demonstration of this new interpretation, the time-independent stationary state QM wave function is substituted to the QED wave function in section "Internal Self-Stress of Energetic Particles": the QED wave function is realized by internal self-stress revealed as energy density at the initial conditions. The renewed energy density is applied to study a unified scheme for generalized chemical reactivity. This is a new kind of chemical force acting in between electrons not in between nuclei. This paves a way for more advanced time-dependent simulation of electronic structure and dynamics in chemical reaction dynamics by tracing trajectories of many electrons. © 2018 Wiley Periodicals, Inc.

2.
Front Comput Neurosci ; 14: 21, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32256331

RESUMO

Hodgkin-Huxley (HH) model has been one of the most successful electrical interpretation of nerve membrane which led to revolutions in the field of computational neuroscience. On the contrary, experimental observations indicate that, an Action Potential (AP) is accompanied with certain physiological changes in the nerve membrane such as, production and absorption of heat; variation of axon diameter, pressure and length. Although, in the early 1900's a Pressure Wave Theory was proposed by E. Wilke, but, due to lack of sophisticated experimental techniques it was left uncharted. Until recently, when Heimburg-Jackson, Hady-Machta and Rvachev, independently proposed Soliton Theory (thermodynamic interpretation of nerve membrane), Mechanical Surface Waves theory (electro-mechanical interpretation) and Rvachev Model (mechano-electrical activation of voltage gated sodium ion channels) respectively; encouraging a deviation from the traditional HH interpretation with justification for the physical changes in the nerve membrane observed experimentally. But, these theories lead to a "hit and miss" scenario because, they do explain certain features (increase/decrease in axon diameter) but miss to explain, correlation between the strength of stimuli and spike rate of AP. Bio-physical models of nerve membrane are thus important for enhancing our understanding regarding the governing dynamics of neural activities encompassing the experimental observations. A novel theory is proposed here which, unravels vortex ring formation due to ion currents in the intracellular and extracellular region leading to variation of pressure causing the increment/decrement in axon diameter. These formations manifest as membrane oscillations which are used to establish a correlation between the strength of stimuli and spike rate of AP. The theory proposed in this paper, brings a paradigm shift in our understanding of neural dynamics from a thorough bio-physical and physiological perspective with promising applications.

3.
Netw Neurosci ; 4(2): 467-483, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32537537

RESUMO

The contribution of structural connectivity to functional brain states remains poorly understood. We present a mathematical and computational study suited to assess the structure-function issue, treating a system of Jansen-Rit neural mass nodes with heterogeneous structural connections estimated from diffusion MRI data provided by the Human Connectome Project. Via direct simulations we determine the similarity of functional (inferred from correlated activity between nodes) and structural connectivity matrices under variation of the parameters controlling single-node dynamics, highlighting a nontrivial structure-function relationship in regimes that support limit cycle oscillations. To determine their relationship, we firstly calculate network instabilities giving rise to oscillations, and the so-called 'false bifurcations' (for which a significant qualitative change in the orbit is observed, without a change of stability) occurring beyond this onset. We highlight that functional connectivity (FC) is inherited robustly from structure when node dynamics are poised near a Hopf bifurcation, whilst near false bifurcations, and structure only weakly influences FC. Secondly, we develop a weakly coupled oscillator description to analyse oscillatory phase-locked states and, furthermore, show how the modular structure of FC matrices can be predicted via linear stability analysis. This study thereby emphasises the substantial role that local dynamics can have in shaping large-scale functional brain states.

4.
J Mol Model ; 24(9): 257, 2018 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-30159609

RESUMO

Application of alpha-oscillator theory to quantum electrodynamics (QED) solves the mystery (as Feynman said) of the double-slit phenomenon involved in the foundation of quantum mechanics (QM). Even if with the same initial condition given, different spots on the screen can be predicted deterministically with no introduction of hidden variables. The general proof has already been published in Ref. [3] and "what is new in this paper" is the concrete numerical algorithm of the extended normal mode technique in section "Concrete numerical algorithm of the extended normal mode technique" and concrete trajectory of one electron in section "Current of one electron". The interference pattern is similar to, but cannot be reproduced quantitatively by, that of QM wave function, contrary to many-years-anticipation: a new prediction, awaiting experimental test over and above the Bohr-Einstein gedanken experiment. QED paves the way for the new generic quantitative theory of electronic structure and dynamics over and above QM. Alpha-oscillator theory presents new aspects of QED from basic physics to material sciences with mathematical rigor. Quantum simulation of nanosized materials is a realization of the new-generation quantum theory. A new era of quantum simulation of nanosized materials is realized. Correct theory of the double-slit phenomenon is QED. Correct quantum theoretical view of the double-slit phenomenon is relativistic quantum field theory (QFT).

5.
J R Soc Interface ; 10(84): 20130221, 2013 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-23676895

RESUMO

Circadian clocks are internal timekeepers present in almost all organisms. Driven by a genetic network of highly conserved structure, they generate self-sustained oscillations that entrain to periodic external signals such as the 24 h light-dark cycle. Vertebrates possess multiple, functionally overlapping homologues of the core clock genes. Furthermore, vertebrate clocks entrain to a range of periods three times as narrow as that of other organisms. We asked whether genetic redundancies play a role in governing entrainment properties and analysed locomotor activity rhythms of genetically modified mice lacking one set of clock homologues. Exposing them to non-24 h light-dark cycles, we found that the mutant mice have a wider entrainment range than the wild types. Spectral analysis furthermore revealed nonlinear phenomena of periodically forced self-sustained oscillators for which the entrainment range relates inversely to oscillator amplitude. Using the forced oscillator model to explain the observed differences in entrainment range between mutant and wild-type mice, we sought to quantify the overall oscillator amplitude of their clocks from the activity rhythms and found that mutant mice have weaker circadian clocks than wild types. Our results suggest that genetic redundancy strengthens the circadian clock leading to a narrow entrainment range in vertebrates.


Assuntos
Adaptação Biológica/fisiologia , Relógios Circadianos/genética , Locomoção/fisiologia , Atividade Motora/fisiologia , Adaptação Biológica/genética , Animais , Criptocromos/genética , Análise de Fourier , Locomoção/genética , Camundongos , Camundongos Transgênicos , Mutação/genética , Fotoperíodo , Razão Sinal-Ruído
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