Indispensable role of quantum theory in the brain dynamics

Recently, Tegmark pointed out that the superposition of ion states involved in the superposition of firing and resting states of a neuron quickly decohere. It undoubtedly indicates that neural networks cannot work as quantum computers, or computers taking advantage of coherent states. Does it also mean that the brain can be modeled as a neural network obeying classical physics? Here we show that it does not mean that the brain can be modeled as a neural network obeying classical physics. A brand new perspective in research of neural networks from quantum theoretical aspect is presented.     

A physical theory of erythrocyte sedimentation

A new physical theory of erythrocyte sedimentation is proposed. Various assumptions underlying Stokes' formula are first criticized. An explicit formula is proposed, taking into account some of the results of recent experimental investigations including the effect of upward flow of plasma and the time course of growth of aggregates. It is generally shown that the sedimentation curve without aggregation never becomes a sigmoid. Our formula is applicable to the increased ESR due to the aggregation of erythrocytes. The sedimentation velocity depends not only on the hematocrit and the ultimate size of the aggregates, but also on the retardation time of the growth of aggregates in conformity with the experimental result of Kernick et al.     

Protein photo-folding and quantum folding theory

The rates of protein folding with photon absorption or emission and the cross section of photon-protein inelastic scattering are calculated from quantum folding theory by use of a field-theoretical method.All protein photo-folding processes are compared with common protein folding without the interaction of photons(non-radiative folding).It is demonstrated that there exists a common factor(thermo-averaged overlap integral of the vibration wave function,TAOI) for protein folding and protein photo-folding.Based on this finding it is predicted that(i) the stimulated photo-folding rates and the photon-protein resonance Raman scattering sections show the same temperature dependence as protein folding;(ii) the spectral line of the electronic transition is broadened to a band that includes an abundant vibration spectrum without and with conformational transitions,and the width of each vibration spectral line is largely reduced.The particular form of the folding rate-temperature relation and the abundant spectral structure imply the existence of quantum tunneling between protein conformations in folding and photo-folding that demonstrates the quantum nature of the motion of the conformational-electronic system.     

Some introductory formalizations on the affine Hilbert spaces model of the origin of life. I. On quantum mechanical measurement and the origin of the genetic code: a general physical framework theory

A physical (affine Hilbert spaces) frame is developed for the discussion of the interdependence of the problem of the origin (symbolic assignment) of the genetic code and a possible endophysical (a kind of "internal") quantum measurement in an explicite way, following the general considerations of Balázs (Balázs, A., 2003. BioSystems 70, 43-54; Balázs, A., 2004a. BioSystems 73, 1-11). Using the Everett (a dynamic) interpretation of quantum mechanics, both the individual code assignment and the concatenated linear symbolism is discussed. It is concluded that there arises a skewed quantal probability field, with a natural dynamic non-linearity in codon assignment within the physical model adopted (essentially corresponding to a much discussed biochemical frame of self-catalyzed binding (charging) of t RNA like proto RNAs (ribozymes) with amino acids). This dynamic specific molecular complex assumption of individual code assignment, and the divergence of the code in relation to symbol concatenation, are discussed: our frame supports the former and interpret the latter as single-type codon (triplet), also unambiguous and extended assignment, selection in molecular evolution, corresponding to converging towards the fixedpoint of the internal dynamics of measurement, either in a protein- or RNA-world. In this respect, the general physical consequence is the introduction of a fourth rank semidiagonal energy tensor (see also Part II) ruling the internal dynamics as a non-linear in principle second-order one. It is inferred, as a summary, that if the problem under discussion could be expressed by the concepts of the Copenhagen interpretation of quantum mechanics in some yet not quite specified way, the matter would be particularly interesting with respect to both the origin of life and quantum mechanics, as a dynamically supported natural measurement-theoretical split between matter ("hardware") and (internal) symbolism ("software") aspects of living matter.     

The brain, time reversal and Libet''s concept of antedating

The brain produces an image of the world outside on its own inner world and should by rights record temporal relationships whose sequence reproduces the sequence of events observed. As, however, visual, auditory and somatic sensory impulses reach the brain after latent periods of differing duration, marked phase differences occur. One way of producing linear phase characteristics with latent periods of 100-500 ms is by means of phase shift and time reversal, referred to in more detail later. With this model it can be shown that Libet's hypothesis of "antedating" (Libet et al., 1979) is consistent in itself, that is, that it contains no inner contradictions (Honderich, 1984). Although there is no sure proof that these mechanisms actually exist, there is in fact no other way of achieving linear phase than by phase shift and time reversal. It must therefore to be assumed that they are present in the brain.     

Association between subjective evaluation and physical parameters for radiographic images optimization

PurposeThe purpose of this study was to develop a methodology to optimize computed radiographic techniques to image the skull, chest, and pelvis of a standard patient.MethodsOptimization was performed by varying exposure levels with different tube voltages to generate images of an anthropomorphic phantom. Image quality was evaluated using visual grading analysis and measuring objective parameters such as the effective detective quantum efficiency and the contrast-to-noise ratio. Objective and subjective evaluations were compared to obtain an optimized technique for each anatomic region.ResultsGold standard techniques provided a significant reduction in X-ray doses compared to the techniques used in our radiology service, without compromising diagnostic accuracy. They were chosen as follows 102 kVp/1.6 mAs for skull; 81 kVp/4.5 mAs for pelvis and 90 kVp/3.2 mAs for chest.ConclusionThere is a range of acceptable techniques that produce adequate images for diagnosis in computed radiography systems. This aspect allows the optimization process to be focused on the patient dose without compromising diagnostic capabilities. This process should be performed through association of quantitative and qualitative parameters, such as effective detective quantum efficiency, contrast-to-noise ratio, and visual grading analysis.     

Comparative evaluation of quantum theory of nerve excitation

Deliberate evaluation of the quantum theory of nerve excitation is made by comparing it with Hill's theory in fitting the experimental data on threshold-frequency relation, optimum frequency (v₀) for nerve excitation and strength-duration relation. Decrease of v₀ and increase of all the time constants (Hill's λ andk, Wei'sT ₂ and spike durationw) with decreasing temperature are interpreted on the basis of the dipole relaxation timeT ₂ but inexplicable from Hill's theory or any other existing theory. The closeness ofk,T ₂ andw values is explained. A variety of experimental results obtained by others is discussed. Finally, a comparison is made between the Hodgkin-Huxley equations and the quantum theory. Most of the facts (electrical and non-electrical) tend to support the thesis that nerve excitation is a macroscopic expression of quantum transitions of dipoles between energy states.     

On the theory of lateral inhibition

Zusammenfassung Das mathematische Modell für das Prinzip der lateralen Inhibition in der Theorie der optischen Perzeption führt auf ein System nichtlinearer Gleichungen für n reelle Variable. Dieses System wird auf Lösbarkeit und eindeutige Lösbarkeit untersucht. Es zeigt sich, daß die Gleichung als Bedingung für die stationären Zustände eines geeigneten zeitabhängigen Systems zu deuten ist. Hier kann man ein diskretes und ein kontinuierliches Modell einführen. In beiden Fällen kann die Frage der Existenz der Lösungen und der Stabilität einigermaßen vollständig geklärt werden. Eine Verallgemeinerung auf kontinuierlich viele Raumvariable ist möglich.     

On the physical origin of biological handedness

In the racemic conglomerate crystallization of over 1000 samples of D, L-sodium-ammonium tartrate the effect of³²P beta irradiation on the weight, optical activity, and crystallite size was measured. Both weight and optical activity showed a statistical dependence on the intensity of beta irradiation. The crystallite size is also affected by the presence of³²P. Asymmetric crystals are suggested to have been potential mediators between asymmetric parity violating forces and molecular asymmetry so that stereo-selective prebiotic chemical reactions involving crystals need not be considered chance processes.No measurable difference in the energy content of optical isomers was found. An upper limit for the direct contribution of weak interactions to electromagnetic ones has been calculated. The mechanism of stereoselective crystal seeding by beta particles is discussed.     

On the physical limnology of Georgian Bay

Georgian Bay comprises the easternmost part of the Michigan-Huron water system and extensive data were collected here in 1974 by the Canada Centre For Inland Waters. Fifty-one stations were monitored between April and December of 1974; the time series recordings of currents and temperature at 10 locations, meteorological recordings at two buoys, and water level recordings from temporary gauges were carried out. Minimum surface temperature of 0 °C persists for one month commencing in late February and maximum surface temperatures occurred in early August (19 °C). The annual heat income for Georgian Bay was estimated to be 43 700 cal · cm^–2. The exchange at Main Channel has a significant influence on water residence and flushing times in Georgian Bay which determines its trophic status.     

On the theory of niche overlap

The factors which are likely to limit niche overlap are studied for a class of idealized biological communities in which several species compete on a onedimensional continuum of resources, e.g., food size. Although the shape of the resource spectrum restricts the composition of possible equilibrium communities, and although this restriction is increasingly stringent as niche overlap increases, such considerations do not in principle put a limit to niche overlap. In analysing the stability of these equilibrium communities, two qualitatively different circumstances need be distinguished. In a strictly unvarying (deterministic) environment, stability sets no limit to the degree of overlap, short of complete congruence. However, in a randomly fluctuating (stochastic) environment, community stability requires that the average food sizes for species adjacent on the resource spectrum must differ by an amount roughly equal to the standard deviation in the food size taken by either individual species. This limit to species packing has a weak (logarithmic) dependence on the degree of environmental variance.This mathematical result is very robust, as is shown by considering, inter alia, a wide range of resource spectrum shapes, and a variety of shapes for the functions describing how the species utilize the resource. The effect of including additional resource dimensions is estimated.The general conclusion from the model is that there is an effective limit to niche overlap in the real world, and that this limit is insensitive to the degree of environmental fluctuation, unless it be very severe. This conclusion seems in accord with an increasing body of field data.     

On the theory of noncovalent binding

It is widely accepted that the binding constant of a receptor and ligand can be written as a two-body integral involving the interaction energy of the receptor and the ligand. Interestingly, however, three different theories of binding in the literature dictate three distinct integrals. The present study uses theory, as well as simulations of binding experiments, to test the validity of the three integrals. When binding is measured by a signal that detects the ligand in the binding site, the most accurate results are obtained by an integral of the Boltzmann factor, where the bound complex is defined in terms of an exclusive binding region. A novel prediction of this approach, that expanding a ligand can increase its binding constant, is borne out by the simulations. The simulations also show that abnormal binding isotherms can be obtained when the region over which the signal is detected deviates markedly from the exclusion zone. Interestingly, the binding constant measured by equilibrium dialysis, rather than by monitoring a localized signal, can yield a binding constant that differs from that obtained from a signal measurement, and that is matched best by the integral of the Mayer factor.     

On the theory of amoeboid movements

It is shown how the application of the principle of maximum energy transformation, discussed in previous papers, leads to expressions which give the probability of occurrence of a pseudopod of a given size and duration in function of other physical constants of the amoeba.