IMBALANCE SYNCHRONIZATION

For both new and 2x new clearances, the damping factor versus separation margin between any bending natural frequency and the synchronous run line shall be within the acceptable region shown on Figme 1.2. If this condition cannot be satisfied, the damped response to imbalance shall be determined (see 1.1.4). 

A condition arising when reaction parameters for different bond-breaking or bond-making processes have developed synchronously as the transition state is approached. Imbalance is common in elimination and addition reactions as well as in proton transfer reactions. See also Synchronous Synchronization... 

Even in atoms in molecules which have no permanent dipole, instantaneous dipoles will arise as a result of momentary imbalances in electron distribution. Consider the helium atom, for example. It is extremely improbable that the two electrons in the Is orbital of helium will be diametrically opposite each other at all times. Hence there will be instantaneous dipoles capable of inducing dipoles in adjacent atoms or molecules. AnothCT way of looking at this phenomenon is to consider the electrons in two or more "nonpolar" molecules as synchronizing their movements (at least partially) to minimize electron-electron repulsion and maximize electron-nucleus attraction. Such attractions are extremely short ranged and weak, as are dipole-induced dipole forces. The energy of such interactions may be expressed as... 

This year marks the 25th anniversary of the principle of nonperfect synchronization (PNS) it was introduced in 19851 as the principle of imperfect synchronization (PIS) but in later papers and reviews2 4 the name was changed due to the awkwardness of the acronym PIS. The foundations of the PNS rest mainly on a marriage between two fundamental concepts of physical organic chemistry, i.e., the concept of intrinsic barriers and that of transition state imbalances. 

The autonomous functions exhibit circadian rhythms which are under the control of a neuronal pacemaker, located in the suprachiasmatic nuclei (SCN) of the hypothalamus. The circadian pacemaker arises from complex dynamics of gene expression and is synchronized to the external light. In the case of mental disorders, the regular rhythms of autonomous functions are obviously disturbed which led to the formulation of the desynchronization hypotheses [8, 9], This does not necessarily contradict the transmitter hypothesis . Transmitter imbalance, of course, also interferes with the inherent system dynamics and can change the endogenous rhythmicity, eventually with the result of desynchronization. A first computational approach which simulates the rhythmicity of the HPA axis and its alterations with scaling of transmitter mediated positive and negative feedback loops is briefly summarized in the second Results section. 

The different concentrations of the ion inside and outside the cells cause a slight electrical potential difference across the cell membrane. It is very small, approximately 100 mV. However, any changes in the concentrations of the ions present change this value. Thus concentrations of ions and electrical charges must be synchronized to allow the cell s materials and charges to flow across a membrane. This cycle in the cells of the heart causes the regular pattern of the heart beat and any imbalance of electrical activity or ion imbalance can cause a malfunction of the... 

In most chemical reactions, several processes must occur between reactants and products. The main processes are the bonds that must be made or broken in the overall reaction. In addition to the main processes, several other processes may occur, including solvation/desolvation, charge delocalization or resonance stabilization. In its most general form, TS imbalance (also known as the Principle of Nonperfect Synchronization) simply states that not all these processes occur synchronously. 

Seizures result from bursts of abnormal synchronous discharging by a network of neurons. Although the mechanisms of seizure generation are still poorly understood, the causes of abnormal firing appear to involve neuronal ion channels and an imbalance between excitatory and inhibitory synaptic function. Various AEDs exhibit different mechanisms of action on neuronal function, causing them to show selective efficacy against different seizure types (Fig. 20.2). 

A related refinement of the picture of the transition-state region is concerned with the question whether the electronic and atomic motions concerned in the bond changes all take place synchronously or whether in the transition state some of them are more advanced than others. The relative extent of individual bond changes in a transition state is called the balance . Clearly any imbalance will affect the electron distribution and therefore the reactivity of the system. Theoretical agrument shows that a measure of the imbalance is the ratio of the Brpnsted coefficient for bond formation to that for bond fission. 

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