Nonlinear charge and energy transport in anharmonic quasi-two-dimensional systems.

We study the localized states of an extra electron in an anisotropic quasi-two-dimensional system in which the electron-lattice interaction and the anharmonicity of the lattice vibrations are dominant in one direction. This model describes layers of polydiacetylene or other polymer chains, beta sheets of polypeptides, multilevel microstructures of conjugated polymers, and other low-dimensional systems. It is shown that for appropriate parameter values of the system an extra electron can excite a soliton-like mobile wave of the lattice deformation, within which it can get self-trapped. Such a bound state of an electron and the lattice deformation form a nonlinear two-component polaron-like entity, which can propagate with minimum of the energy dissipation. Our findings are based on the variational approach and the full numerical solution of the coupled system of nonlinear equations. These results suggest that the experimentally measured charge and energy transport over macroscopic distances in the above-mentioned systems can be provided by the soliton mechanism and thus have a potential impact on the theoretical background of the numerous applications of low-dimensional materials in nanoelectronics.

Impact of structure on the delayed luminescence of d-Glucose-based polymer chains.

Glucose is a natural chemical compound and is one of the most abundant organic molecules in nature. Plants and algae are able to produce it from water and carbon dioxide during photosynthesis, using energy of photons coming from the sun. It is very important in life processes because, in energy metabolism, Glucose is the most important source of energy in all organisms. As energy reservoir it is partially stored as a polymer, in plants mainly as starch and amylopectin and in animals as glycogen. Moreover it is used as cellulose, the most abundant carbohydrate, to strengthen plants and algae cell walls. In this paper we study the Delayed Luminescence from Glucose and its polymers, Amylose and Cellulose, composed by chains of glucose connected by different bond, as well as Glucose water solution, in order to acquire new knowledge on the mechanisms responsible for this phenomenon and check the possibility to give in-depth analysis of possible collective states present in Glucose-based structures. The phenomenon of DL in biological systems is not a byproduct, as one can naively expect. Instead, it is a property and necessity of the condensed matter, which can be also used as a tool to study the latter. It is a manifestation of the physical and biochemical processes in the system, on one hand side, and, on the other hand side, of its structural properties, in particular, of the presence and type of crystal-like structure, resulting in specific energy spectrum and electron transitions, as will be presented below. We show that the quantum yield and time trends of the Delayed Luminescence depend on the structure of systems under study. Significant differences in Delayed Luminescence parameters from cellulose before and after imbibition have been observed, indicating that Delayed Luminescence could be used to discriminate between various structures and follow the formation or demolition of them. The experimental results qualitatively agree with the soliton mechanism of the Delayed luminescence.

Modeling Meridians Within the Quantum Field Theory.

We present here a model of meridians in the formalism of the gauge theory paradigm of quantum field theory with spontaneous breakdown of symmetry. We discuss the origin and dynamic self-focusing propagation of the electromagnetic field in coherent states and the role it plays in our meridian modeling. Within this frame, we consider the formation of solitary waves on proteins and anatomical filamentary structures and discuss nondissipative energy transport. Finally, we analyze the relation of meridians with anatomical filamentary structures, the reciprocal actions between meridians, and biochemical activity and the key role played by free energy, internal energy, and entropy.

Nonlinearity, coherence and complexity: Biophysical aspects related to health and disease.

Biological organisms are complex open dissipative systems whose dynamical stability is sustained due to the exchange of matter, energy and information. Dynamical stability occurs through a number of mechanisms that sustain efficient adaptive dynamics. Such properties of living matter can be the consequence of a self-consistent state of matter and electromagnetic field (EMF). Based on the soliton model of charge transport in redox processes, we describe a possible mechanism of the origin of endogenous EMF and coherence. Solitons are formed in polypeptides due to electron-lattice interaction. Solitons experience periodical potential barrier, as a result of which their velocity oscillates in time, and, hence, they emit electromagnetic radiation (EMR). Under the effect of such radiation from all other solitons, the synchronization of their dynamics takes place, which significantly increases the intensity of the general EMF. The complex structure of biological molecules, such as helical structure, is not only important for "structure-function" relations, but also the source of the stability of biophysical processes, e.g. effectiveness of energy and charge transport on macroscopic distances. Such a complex structure also provides the framework for the spatiotemporal structure of the endogenous EMF. The highly hierarchical organization of living organisms is a manifestation of their complexity, even at the level of simple unicellular organisms. This complexity increases the dynamical stability of open systems and enhances the possibility of information storage and processing. Our findings provide a qualitative overview of a possible biophysical mechanism that supports health and disease adaptive dynamics.

Influence of electromagnetic field on soliton-mediated charge transport in biological systems.

It is shown that electromagnetic fields affect dynamics of Davydov's solitons which provide charge transport processes in macromolecules during metabolism of the system. There is a resonant frequency of the field at which it can cause the transition of electrons from bound soliton states into delocalised states. Such decay of solitons reduces the effectiveness of charge transport, and, therefore, inhibits redox processes. Solitons radiate their own electromagnetic field of characteristic frequency determined by their average velocity. This self-radiated field leads to synchronization of soliton dynamics and charge transport processes, and is the source of the coherence in the system. Exposition of the system to the oscillating electromagnetic field of the frequency, which coincides with the eigen-frequency of solitons can enhance eigen-radiation of solitons, and, therefore, will enhance synchronization of charge transpor, stimulate the redox processes and increase coherence in the system. Electromagnetic oscillating field causes also ratchet phenomenon of solitons, i.e., drift of solitons in macromolecules in the presence of unbiased periodic field. Such additional drift enhances the charge transport processes. It is shown that temperature facilitates the ratchet drift. In particular, temperature fluctuations lead to the lowering of the critical value of the intensity and period of the field, above which the drift of solitons takes place. Moreover, there is a stochastic resonance in the soliton dynamics in external electromagnetic fields. This means, that there is some optimal temperature at which the drift of solitons is maximal.

Copper ion fluxes through the floating water bridge under strong electric potential.

We have performed a series of experiments applying high voltage between two electrodes, immersed in two beakers containing bidistilled water in a way similar to experiments conducted by Fuchs and collaborators, which showed that a water bridge can be formed between the two containers. We also observed the formation of water bridge. Moreover, choosing different pairs of electrodes depending on the material they are made up of, we observed that copper ions flow can pass along the bridge if the negative electrode is made up of copper. We show that the direction of the flux not only depends on the applied electrostatic field but on the relative electronegativity of the electrodes too. These results open new perspectives in understanding the properties of water. We suggest a possible explanation of the obtained results.

Michael Kasha: from photochemistry and flowers to spectroscopy and music.

A brilliant scientist and an outstanding personality who was one of the founders of modern photochemistry-Michael Kasha-is the subject of this Essay. Kasha's rule and the Kasha effect both bear his name, and he also discovered the chemical production of singlet molecular oxygen, and was a pioneer of excited-state proton transfer systems. Kasha combined his passion for chemistry and physics with that for music, photography, and botany.

Light as a trigger and a probe of the internal dynamics of living organisms.

It has been reported that the colors perceived behind closed eyes provide an indication of the psychophysical state of a subject. We discuss this phenomenon in the light of recently developed approaches to living organisms, based on the interplay between matter organization, biochemistry and electrodynamics. "When there is no energy, there is no color, no shape, no life." Caravaggio (1571-1610).

Effects of periodic electromagnetic field on charge transport in macromolecules.

We study effects of periodic fields on charge transport in macromolecules and show that solitons acquire complex dynamics induced by the interplay between the periodic in time external field, energy dissipation, and depends on the molecule symmetry. Soliton dynamics is a superposition of the oscillations of the soliton c.m.c. with the frequency of the external field and directed current. Even unbiased periodic in time fields can cause drift of solitons (the ratchet effect) in the Peierls-Nabarro periodic potential. This effect has a threshold with respect to the intensity and frequency of the field. We calculate the dependence of the amplitude of soliton oscillations and the velocity of the drift on the intensity of the field, its frequency, and energy dissipation. Thus, we show that nonlinear charge transport processes in a field which is periodic in time acquire completely different dynamics than linear processes. This clearly plays a role in metabolism of biosystems.

Nonlinear mechanism for weak photon emission from biosystems.

The nonlinear mechanism for the origin of the weak biophoton emission from biological systems is suggested. The mechanism is based on the properties of solitons that provide energy transfer and charge transport in metabolic processes. Such soliton states are formed in alpha-helical proteins. Account of the electron-phonon interaction in macromolecules results in the self-trapping of electrons in a localized soliton-like state, known as Davydov's solitons. The important role of the helical symmetry of macromolecules is elucidated for the formation, stability and dynamical properties of solitons. It is shown that the soliton with the lowest energy has an inner structure with the many-hump envelope. The total probability of the excitation in the helix is characterized by interspine oscillations with the frequency of oscillations, proportional to the soliton velocity. The radiative life-time of a soliton is calculated and shown to exceed the life-time of an excitation on an isolated peptide group by several orders of magnitude.

Nonlinear dependence of the delayed luminescence yield on the intensity of irradiation in the framework of a correlated soliton model.

We generalize the correlated soliton model in order to describe the delayed luminescence arising from biological systems after their exposition to the irradiation by relatively high dose (high intensity and/or long duration of irradiation). The quantum yield of the delayed luminescence is calculated as a function of the irradiation and is shown to depend nonlinearly on the intensity and dose of the irradiation. At relatively low intensity, the yield of luminescence increases with increasing dose, and monotonously reaches saturation. At high intensity of the irradiation, the yield of the photosystem under study is restricted from above by the concentration of photosystem units. As a result, the total yield of the delayed luminescence first increases with the dose till the maximum value that, in the general case, is less than the maximum number of available photosystem units. With further increase of the dose, the yield gradually decreases, reaching the saturation value at large dose of illumination. These results are obtained within the steady state approximation in the description of the luminescence kinetics. To check the applicability of this approximation at high levels and large time of illumination, the corrections to the steady state solution have been calculated, and shown to decrease exponentially with increase in time till the small finite constant value. The results of the theoretical model are shown to describe well the experimental data on the dose dependence of the quantum yield of the luminescence of algae Acetabularia acetabulum, for which the correlated soliton model describes well the kinetics of the delayed luminescence at low levels of irradiation.