Cosmophysical effects in processes of various nature

The explanations to the special number of journal "Biophysics" are presented.     

Kinetic aspects of macroscopic fluctuations in solutions of liver alcohol dehydrogenase

Kinetic analysis of macroscopic fluctuations in alcohol dehydrogenase reaction was carried out. The integral form of Michaelis-Menten equation was used. It is shown that reaction rate fluctuations to be observed in experiment are connected with kinetic constants of relative affinity of ADG to NAD and NAD X H.     

Discrete conductance fluctuations in lipid bilayer protein membranes

Discrete fluctuations in conductance of lipid bilayer membranes may be observed during the initial stages of membrane interaction with EIM ("excitability inducing material"), during destruction of the EIM conductance by proteolysis, and during the potential-dependent transitions between low and high conductance states in the "excitable" membranes. The discrete conductance steps observed during the initial reaction of EIM with the lipid membranes are remarkably uniform, even in membranes of widely varying lipid composition. They range only from 2 to 6 x 10_-10 ohm_-1 and average 4 x 10_-10 ohm_-1. Steps found during destruction of the EIM conductance by proteolysis are somewhat smaller. The transition between high conductance and low conductance states may involve steps as small as 0.5 x 10_-10 ohm_-1. These phenomena are consistent with the formation of a stable protein bridge across the lipid membrane to provide a polar channel for the transport of cations. T6he uniform conductance fluctuations observed during the formation of these macromolecular channels may indicate that the ions in a conductive channel, in its open state, are largely protected from the influence of the polar groups of the membrane lipids. Potential-dependent changes in conductance may be due to configurational or positional changes in the protein channel. Differences in lipid-lipid and lipid-macromolecule interactions may account for the variations in switching kinetics in various membrane systems.     

The nature of fluctuations in spontaneous otoacoustic emission

The nature of fluctuations of sound pressure during spontaneous otoacoustic emission is studied. The phenomenological mechanism of realization of positive feedback in cochlear is proposed. It is based on usage of hair cells ionic channels. By means of this model it is shown that spontaneous emission fluctuations are determined with thermal oscillations. The mass of the vibrating part of the basilar membrane, its dimensions and elasticity are calculated.     

A theoretical approach to "macroscopic fluctuations" effect

At present there is no generally accepted theory of the effect of macroscopic fluctuations. It the article, an attempt is made to relate this effect to some basic properties of quantum systems, in particular, to the formal absence of dynamic chaos in these systems. Based on this approach, it was shown why the level of the effect must be of the same order of magnitude as the level of noise and cannot exceed this level as the number of experiments increases. It was shown qualitatively what is the cause of the similarity of histograms observed in different experiments.     

Estimation of ion channel kinetics from fluctuations of macroscopic currents

For single channel recordings, the maximum likelihood estimation (MLE) of kinetic rates and conductance is well established. A direct extrapolation of this method to macroscopic currents is computationally prohibitive: it scales as a power of the number of channels. An approximated MLE that ignored the local time correlation of the data has been shown to provide estimates of the kinetic parameters. In this article, an improved approximated MLE that takes into account the local time correlation is proposed. This method estimates the channel kinetics using both the time course and the random fluctuations of the macroscopic current generated by a homogeneous population of ion channels under white noise. It allows arbitrary kinetic models and stimulation protocols. The application of the proposed algorithm to simulated data from a simple three-state model on nonstationary conditions showed reliable estimates of all the kinetic constants, the conductance and the number of channels, and reliable values for the standard error of those estimates. Compared to the previous approximated MLE, it reduces by a factor of 10 the amount of data needed to secure a given accuracy and it can even determine the kinetic rates in macroscopic stationary conditions.     

The nature and perception of fluctuations in human musical rhythms

Although human musical performances represent one of the most valuable achievements of mankind, the best musicians perform imperfectly. Musical rhythms are not entirely accurate and thus inevitably deviate from the ideal beat pattern. Nevertheless, computer generated perfect beat patterns are frequently devalued by listeners due to a perceived lack of human touch. Professional audio editing software therefore offers a humanizing feature which artificially generates rhythmic fluctuations. However, the built-in humanizing units are essentially random number generators producing only simple uncorrelated fluctuations. Here, for the first time, we establish long-range fluctuations as an inevitable natural companion of both simple and complex human rhythmic performances. Moreover, we demonstrate that listeners strongly prefer long-range correlated fluctuations in musical rhythms. Thus, the favorable fluctuation type for humanizing interbeat intervals coincides with the one generically inherent in human musical performances.     

Dependence of "macroscopic fluctuations" from cosmophysical factors. Spatial anisotropy

It was shown in experiments with collimators that the changes with time in the shape of histograms constructed from the measurements of the alpha-activity of 239Pu microsamples depend on the direction of the flow alpha-particles. If the flow of alpha-particles was directed to the Polar Star, the dependence of the probability of the realization of histograms of similar shape on time disappeared. The measurements of alpha-particle flows directed to the East and West revealed a high probability of the repeated realization of histograms of similar shape in 1436 min, i.e., in a sederal day. A comparison of "west" and "east" histograms showed a high probability of the realization of similar "west" histograms 718 min (half a sideral day) later than "east" histograms. The results suggest that the shape of histograms depends on the pattern of the starry sky and the space-time inhomogeneity corresponding to this pattern.     

Discrete localization of various fatty-acid-binding proteins in various cell populations of mouse retina

The analysis of myenteric neurons is becoming increasingly important for the assessment of enteric nervous system injury and degeneration occurring in motor disorders of the gut. Limited information is presently available on the quantitative estimation of myenteric neurons and glial cells in paraffin-embedded colonic sections; additional data would be useful for diagnostic purposes. In this morphometric study, we performed immunohistochemistry to count myenteric neurons and glial cells in paraffin sections of human colon. Serial cross sections of formalin-fixed paraffin-embedded full-thickness normal human left colon (n = 10, age-range: 50–72 years) were examined. HuC/D and S100β antigens were found to be the best markers for the detection of neurons and glial cells, respectively. Significant correlations were noted between the numbers of neurons/glial cells and the respective myenteric ganglion areas. These findings suggest that HuC/D-S100β-immunostained paraffin cross sections of human colon can be regarded as valuable tools for the quantitative estimation of myenteric neurons and glial cells. Based on the present method, only a limited number of paraffin sections are needed for reliable quantitative assessments of myenteric ganglion cells, thus allowing fast and simple approaches in the settings of the histopathological diagnosis of colonic motility disorders and retrospective evaluations of pathological archival tissue specimens. R. De Giorgio is the recipient of grants from the Fondazione Del Monte di Bologna e Ravenna and from the Fondazione Cassa di Risparmio, Bologna, Italy. The authors declare no conflicting interests.     

Stochastic processes in particle-number fluctuations in an electron-photon shower

The paper is concerned with the existence and asymptotic character of the nonlinear boundary value problemdG/dt=F(t,G,F, ¦α?β¦) (1) ¦α?β¦dF/dt=g(t,G,F, ¦α?β¦)G(o,¦α?β¦)=k ₁,G(∞,¦α?β¦)=k ₂ (2) as ¦α?β¦→ o+ The discussion is related to the problem of particle-number fluctuations in the theory of cosmic radiation andG andF denote respectively the probability generating functions for the electron distribution in an electron-initiated and a photon-initiated shower. A solution of the system (1) satisfying the boundary conditions (2) is constructed so that specified limiting conditions are fulfilled.     

Regeneration processes in various species of planarians

Blastema growth and functional maturation of the pharynx during regeneration in various planarian species were compared. The intensity of blastema growth was highest in Polycelis tenuis; the lowest, in Schmidtea mediterranea. In the sexual and asexual races of Girardia tigrina blastema growth differed inconsiderably. The function of the pharynx during the regeneration of caudal fragments lacking pharynx was manifested in G. tigrina in the usual amount of time, while in the regeneration of head fragments lacking pharynx, this function occured earlier. In other planarian species of the other two typed, the times of pharynx regeneration had no regular character and took longer compared to the same process in G. tigrina.     

A macroscopic model describing yield and maintenance relationships in aerobic fermentation processes

The present paper presents a generalized treatment of the principles of elemental and enthalpy balances which are applied to aerobic fermentation processes. It is shown that strict relations do exist between the various yield factors of biomass or product on substrate, oxygen, carbon dioxide, and between the various maintenance coefficients. These relations are confirmed from the existing body of literature data on yield and maintenance coefficients. Another consequences of the application of elemental balances is the existence of limits for the maximum biomass yield on substrate and oxygen, which depend on the degree of reduction of the substrates with different degree of reduction. It appears from this model that substrates with a high degree of reduction are C limited and substrates with a low degree of reduction are energy limited. Finally the effects of temperature on yield and maintenance coefficients are analyzed from the existing body of literature data. It can be concluded that the maintenance coefficients follow an Arrhenius type of relationship and that yield is temperature independent. The literature data seem to indicate that a degree of reduction of about 4 is optimal for the carbon and energy needs for biomass formation.     

Sir-dependent downregulation of various aging processes

Using a new genetic selection approach in yeast termed fitness-based interferential genetics (FIG), genes that are in an antagonistic relationship with the Sir complexes were selected. Many of the functionally well-defined genes belong to various aging processes occurring in this organism. Three genes are somehow involved in glucose utilization (HXT4,YIL107c, EMI2). Another gene, CDC25, encodes the main regulator of the cyclic AMP pathway in response to glucose. STM1 has been implicated in the control of apoptosis, and indeed, this work shows that disruption of this gene results, among other phenotypes, in resistance to aging. LCB4, encoding a sphingoid bases kinase is linked to the cell integrity pathway. Two other genes, FHL1 and PEP5, are involved in the control of ribosome formation and vacuole biogenesis, respectively; and five genes, presently having unknown functions, could be new potentially interesting candidates for further studies in relation to yeast replicative aging. It is proposed that most, if not all, selected genes are downregulated by the Sir complexes. In addition to changing our view of the mechanisms used by the Sir complexes for extending life span in yeast, these findings could contribute to a better understanding of the role of the Sir complexes in the higher eukaryotes.     

On the occurrence of various species of yeast in nature

Summary A number of yeasts were isolated from various natural sources such as slime fluxes of trees, insects and insect frass, flowers and similar substrata. Several of the isolates represented species described in recent years. The additional isolations reported here contributed additional knowledge regarding the natural habitat of some of the species. Conclusions are offered regarding the ecology ofSaccharomyces kluyveri, S. phaselosporus, S. rosei, S. veronae, S. wickerhamii, Hansenula californica, H. mirakii, H. minuta, Pichia kluyveri, P. pastori, P. rhodanensis, P. silvestris, P. vanriji, Candida albicans, C. claussenii, Torulopsis glabrata, T. candida, Cryptococcus albidus, Cr. diffluens, Cr. laurentii, Rhodotorula graminis, Rh. texensis, andAscocybe grovesii. Various other species are listed in tabular form and by isolation source.     

Correlation of space-time ranges in ecological hierarchies of various nature

Relations between characteristic scales of time and space are analyzed for the hierarchical systems of a various nature. The available data fit well to the power relation: [T] = a[L]b, where [T] and [L] are characteristic ranges of time and space, b--scaling exponent, a--conversion coefficient. The spatio-temporal scales of ocean physical and biological (pelagic) processes are closely overlapped. Contrastingly, the scale for terrestrial and benthic ecosystems and their environments differ noticeably. For terrestrial and benthic ecological systems, and also for atmospheric phenomena, the b values significantly less than 1, that indicates a significant coherence of structure-generating processes integrating lower-level hierarchical units to a higher-level entity. For geomorphological structures, both terrestrial and oceanic, the scaling parameters has appeared close to 1 (a "direct transfer" type of generating processes). For plankton systems, which are related with water masses, the b values vary from 1 (processes of direct transfer) up to 2 (random dispersal or diffusion processes). The author attributes this difference to the principle distinctions in dynamic properties of the physical environments for terrestrial (and probably, benthic) and plankton organisms. Finally, for the units (structures or processes) of one and the same organization level, scaling exponents are significantly higher and close to 2 (diffusive dynamics) or more (rigid spatial limitation). Thus, the development of many ecological structures looks dynamically like diffusion or gradual growth, but their putting in the higher-level order (integrity) is a qualitative leap forward and demands appropriate cooperative organizational processes.