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The redox metabolic paradigm of murburn concept advocates that diffusible reactive species (DRS, particularly oxygen-centric radicals) are mainstays of physiology, and not mere pathological manifestations. The murburn purview of cellular function also integrates the essential principles of bioenergetics, thermogenesis, homeostasis, electrophysiology, and coherence. In this context, any enzyme that generates/modulates/utilizes/sustains DRS functionality is called a murzyme. We have demonstrated that several water-soluble (peroxidases, lactate dehydrogenase, hemogoblin, etc.) and membrane-embedded (Complexes I-V in mitochondria, Photosystems I/II in chloroplasts, rhodopsin/transducin in rod cells, etc.) proteins serve as murzymes. The membrane protein of Na,K-ATPase (NKA, also known as sodium-potassium pump) is the focus of this article, owing to its centrality in neuro-cardio-musculo electrophysiology. Herein, via a series of critical queries starting from the geometric/spatio-temporal considerations of diffusion/mass transfer of solutes in cells to an update on structural/distributional features of NKA in diverse cellular systems, and from various mechanistic aspects of ion-transport (thermodynamics, osmoregulation, evolutionary dictates, etc.) to assays/explanations of inhibitory principles like cardiotonic steroids (CTS), we first highlight some unresolved problems in the field. Thereafter, we propose and apply a minimalist murburn model of trans-membrane ion-differentiation by NKA to address the physiological inhibitory effects of trans-dermal peptide, lithium ion, volatile anesthetics, confirmed interfacial DRS + proton modulators like nitrophenolics and unsaturated fatty acid, and the diverse classes of molecules like CTS, arginine, oximes, etc. These explanations find a pan-systemic connectivity with the inhibitions/uncouplings of other membrane proteins in cells.

It is well-known that the process of mixing two solutions of different concentrations may produce energy. The change in Gibbs energy upon mixing is believed to be the source of energy. However, the change in the Gibbs energy is independent of the way of mixing, i.e., irreversible (without work production) or reversible (with the obligatory production of work). The Gibbs energy cannot be an energy source for producing work. The entropy of mixing solutions and the environment has been considered to elucidate the role of the Gibbs energy in the reversible process. It is shown that the environment takes active part in energy production. The Gibbs energy may be a mathematical means for performing thermodynamic calculations.

The transport of water through a semipermeable membrane in Pressure Retarded Osmosis (PRO) has been considered. The water flux is believed to consist of two components. The water flux from feed to draw solution is due to the difference in the water concentrations of feed and draw solutions. This flux is controlled by diffusion in accordance with Fick's Law. Second flux from draw to feed solution is caused by pressure applied to the draw solution. The total flux is proportional to the difference between the osmotic pressure and that applied to the draw solution. The membrane is assumed to be a set of several homogeneous layers of different thickness and with various diffusion coefficients. Each homogeneous layer can be characterized by diffusion resistance. The diffusion resistance of the membrane ( r ) is the sum of the diffusion resistance of individual layers. The water permeability coefficient ( A ) depends on the membrane diffusion resistance A = 1/( RTr ).

Fulvic acid (Henan ChangSheng Corporation) photoinduced degradation of non-UVA-absorbing herbicide amitrole (3-amino-1,2,4-triazole, AMT) as a way for its removal from polluted water was investigated in details. It was shown that the main primary species generated by fulvic acid under UVA radiation, triplet state and hydrated electron, are not directly involved in the herbicide degradation. AMT decays in reactions with secondary intermediates, reactive oxygen species, formed in reactions of the primary ones with dissolved oxygen. Singlet oxygen is responsible for 80% of herbicide oxidation, and

Anoxic wetlands are an important source for the greenhouse gas CH4, much of which is emitted in form of gas bubbles. The conditions for formation of gas bubbles have recently been described by an analytical model, which allows the prediction of fluxes by first physical principles using the knowledge of gas concentration profiles and/or gas production rates. We tested parts of this model by experiments using microcosms of flooded, non-vegetated and homogeneous rice field soil incubated under different gas atmospheres and at different temperatures. In these experiments we determined rates of CH4 and CO2 production, upper boundaries of the bubble zone, gas-filled porosities and vertical profiles of dissolved CH4, CO2 and N2. The results of our experiments confirmed that by knowing only one of the following parameters, i.e. CH4 production, diffusive CH4 flux and depth of upper boundary of bubble zone, the remainder could be predicted from the model. On average, predicted values differed from experimental ones by a factor of 0.4 –2.7, depending on which parameter was taken as an input for the model. It was possible to predict the percentage of gas bubble flux from measured CH4 emission rates under the experimental conditions, which was on the order of 90%. The confrontation of the model with experimental data showed that the effect of the shallow upper oxic layer on bubble formation was negligible and that the CH4 diffusive flux is easily underestimated by experiments lacking sufficient spatial resolution. Therefore, CH4 production rates lower than in our microcosms would allow a more precise test of the model by creating less steep concentration gradients, which, however, would require long incubation times to purge the dissolved N2 from the soil by ebullition and to reach true steady state.

The calculations of phosphorescence quantum yield in the presence of moving acceptors are performed. The acceptor concentration is assumed to be small. Quenching is described by exchange mechanism. The calculations are performed for diffusion and hopping models of the acceptor migration. The oxygen diffusion coefficient in the diffusion model and the time between two jumps in the hopping model are calculated for the system phenanthrene-oxygen in organic glasses frozen to 77 K. The possibility of determining the diffusion coefficients ≈ 10 -17 -10 -16 cm 2 /s is shown.

The theoretical and applied aspects of the spectroscopy of light scattering media are examined and approximate methods for the solution of the radiative transfer equation are described. The data obtained with the aid of certain approximations are compared with the results of accurate calculations and certain experimental light scattering data are analysed. The bibliography includes 123 references.