The "near zone" effect in dynamic chaos

The dynamics of the system with a determined chaotic behavior (Lorentz system) was studied by comparing the histograms. It was shown that the dynamics of the system exhibits phenomena similar to those observed in studies of fluctuations in physical systems. In particular, upon comparison of histograms constructed from different time intervals, the "near zone" effect makes itself evident. It was shown that a very slight modulation of only one parameter of the system leads to a change in behavior.     

The effect of microwave irradiation on the peroxide modification of low density lipoproteins in human blood serum

In experiments in vitro the electromagnetic field of 2375 mHz, 500 microW/cm2 was shown to influence peroxide modification of low density lipoproteids. It was also shown that this modifying effect was prevented by high density lipoproteids that decreased the level of lipid peroxidation.     

On atomic nuclear fusion processes at low temperatures. Enhancement of potential barrier transmission probability due to the so-called barrier anti-Zeno effect

It is known that in quantum mechanics the observation of an experiment may in some cases change the results of this experiment. In particular, this occurs for the so-called Zeno effect. It is shown that, unlike the standard Zeno effect for which observation reduces its probability, for a particle that penetrates a potential barrier the opposite situation (called the barrier anti-Zeno effect) can occur, i.e., observation can considerably increase the probability of barrier penetration. The possibility of utilizing the barrier anti-Zeno effect for explaining the paradoxical results of experiments on “cold nuclear fusion” that have been observed in various, including biological, systems is discussed. (According to the experimentalists who performed such studies, in these systems energy release that cannot be explained by any chemical processes, as well as changes of the isotope and even elemental composition of the studied substance, occur).     

A quantitative analysis of the voltage-current relationships of fixed charge membranes and the associated property of "punch-through"

A theoretical analysis of the voltage-current relationship is carried out in a membrane consisting of two fixed charge regions, of opposite sign, in contact. This is achieved by applying the diffusion equations to this system in conjunction with the Poisson-Boltzmann equation. The latter has been successfully applied by Mauro to determine the profiles of the electrostatic potential in his treatment of the capacitative property of such a system. It is shown that the system displays the property of rectification and is very similar in many respects to a solid state P-N junction diode. It is also shown that for the case of reverse bias, an electrical breakdown phenomena can occur. This is referred to as the “punch-through” effect. “Punch-through” was observed in experiments on the electrical characteristics of the membranes of Chara australis and Nitella sp. The experimental results are discussed in relation to the theoretical analysis.     

Effect of the aeration and agitation states on tetracycline biosynthesis in semiproduction-capacity apparatus]

The results of the experiments on determination of the effect of aeration and agitation conditions on biosynthesis of tetracycline in the apparatus of semi-production capacity are discussed. It was shown that the antibiotic production level was not connected with the rate of oxygen solution expressed in the sulphite numbers, i.e. this parameter cannot be used as a scaling-up criterion. Accumulation of the antibiotic in the fermentation broth depended on the volume of the air supplied for aeration. It was determined that the level of CO2 dissolved in the fermentation broth did not reach the values having an inhibitory effect on the biosynthetic process.     

米非司酮基因诱导调控系统

在基因表达和基因治疗研究中,需要目的基因在特定的时间以适当的水平实现其表达,目的基因过度表达或不适当的表达将影响实验结果,在疾病治疗中甚至会产生致命的副作用,实现对目的基因的表达时间和表达水平的精确调控是一个非常关键的问题。目前生物学家们已构建了多种新型的基因表达调控系统,其中米非司酮诱导调控系统具有诱导效率高,背景表达低,安全性高等诸多优点,是基因调控研究中的重要进展,也是目前最有应用前景的调控系统之一。本文就其结构设计和应用研究方面的进展作一简要综述。     

Effect of sigetin on the concentration of triglycerides and cholesterol in rat blood and liver]

It was shown in experiments on male rats that sygethin an analogue of synesterol devoid of estrogenic effect decreased cholesterol level in the intact animals and diminished hypercholesterolemia induced by dexamethasone. Sygethin inhibited the hypertriglyceridemia induced by diethylstilbestrol, as well as by ethanol and dexamethasone.     

Autogenous control of Escherichia coli threonyl-tRNA synthetase expression in vivo

The regulation of the expression of thrS, the structural gene for threonyl-tRNA synthetase, was studied using several thrS-lac fusions cloned in lambda and integrated as single copies at att lambda. It is first shown that the level of beta-galactosidase synthesized from a thrS-lac protein fusion is increased when the chromosomal copy of thrS is mutated. It is also shown that the level of beta-galactosidase synthesized from the same protein fusion is decreased if wild-type threonyl-tRNA synthetase is overproduced from a thrS-carrying plasmid. These results strongly indicate that threonyl-tRNA synthetase controls the expression of its own gene. Consistent with this hypothesis it is shown that some thrS mutants overproduce a modified form of threonyl-tRNA synthetase. When the thrS-lac protein fusion is replaced by several types of thrS-lac operon fusions no effect of the chromosomal thrS allele on beta-galactosidase synthesis is observed. It is also shown that beta-galactosidase synthesis from a promoter-proximal thrS-lac operon fusion is not repressed by threonyl-tRNA synthetase overproduction. The fact that regulation is seen with a thrS-lac protein fusion and not with operon fusions indicates that thrS expression is autoregulated at the translational level. This is confirmed by hybridization experiments which show that under conditions where beta-galactosidase synthesis from a thrS-lac protein fusion is derepressed three- to fivefold, lac messenger RNA is only slightly increased.     

The hemathological reactions in rats after partial screening from natural electromagnetic fields

The influence of partial screening of EMF on the composition of white blood cells was studied in the experiments on rats. Two kinds of copper rings were used in these experiments: individual for each rat and common for the cage. It was shown that inside the ring the composition of blood cells was changed--in 3-5 hours the number of granulocytes increased and in 24 hours it restored to the initial level. The effect was more expressive in the experiments using individual rings. In control groups the experiment with plastic rings didn't reveal this effect. It was presumed that EMF prevented the decay of granulocytes. It leads to the increase of their guantity. It was revealed that there was a positive correlation between Ki-indexes of geomagnetic field (GMF) in 1-2 days before the experiments and the number of granulocytes in rats during 1995-2002. Ki-indexes reflect the degree of GMF disturbance. During magnetic storms the spreading of EMF in radio-frequency range changes. It was presumed that the effect of partial screening of EMF of rats and the activity of magnetic storms are similar in their influence on the composition of white blood cells of rats.     

Simple contrivance "clamps" end-tidal PCO(2) and PO(2) despite rapid changes in ventilation.

The device described in this study uses functionally variable dead space to keep effective alveolar ventilation constant. It is capable of maintaining end-tidal PCO(2) and PO(2) within +/-1 Torr of the set value in the face of increases in breathing above the baseline level. The set level of end-tidal PCO(2) or PO(2) can be independently varied by altering the concentration in fresh gas flow. The device comprises a tee at the mouthpiece, with one inlet providing a limited supply of fresh gas flow and the other providing reinspired alveolar gas when ventilation exceeds fresh gas flow. Because the device does not depend on measurement and correction of end-tidal or arterial gas levels, the response of the device is essentially instantaneous, avoiding the instability of negative feedback systems having significant delay. This contrivance provides a simple means of holding arterial blood gases constant in the face of spontaneous changes in breathing (above a minimum alveolar ventilation), which is useful in respiratory experiments, as well as in functional brain imaging where blood gas changes can confound interpretation by influencing cerebral blood flow.     

Experimental data on hygienic norms for antibiotics of the tetracycline group]

Toxicity of tetracyclines was studied experimentally on different species of laboratory animals. It was shown that tetracycline, oxytetracycline and chlortetracycline were close by their chemical structure and physico-chemical properties, as well as by the main toxicity parameters, i.e. acute toxicity, cumulative activity, skin-irritating and sensitizing effect. Under the conditions of subacute experiments the above 3 antibiotics induced evenly pronounced one direction changes in animals. The data obtained during the experiments provided recommendation of the level of 0.1 mg/m3 as the maximum allowable concentration (MAC) of oxytetracycline and chlortetracycline, i.e. the same level as the previously recommended for tetracycline.     

Experimental studies to set hygienic standards for benzylpenicillin in the air of a work area

The character and level of benzylpenicillin toxic effect was studied in accordance with the methodic instruction for performance of the experiments on toxicological estimation and hygienic norms of antibiotics in the air of working areas in production premises. It was shown that the antibiotic was of low toxicity under conditions of a single exposure, did not cumulate and had no local irritating and resorbing effect. It was shown to be an allergen. Prolonged inhalation of benzylpenicillin in a concentration of 14 mg/m3 resulted in reversible changes in the function of the kidneys and liver of the animals, their sensitization and development of pronounced dysbacteriosis of the mouth and intestine mucosa. In a concentration of 1 mg/m3 benzylpenicillin had no general toxic and sensitizing effect but induced reversible changes in the normal autoflora. This allowed the authors to consider the above concentration to be maximum with respect to the antibacterial effect. On the basis of the experiments the maximum permissible norm (MPN) of the aerosol of benzylpenicillin disintegration was recommended at the level of 0.1 mg/m3.     

Serotonin reuptake blocker fluoxetine suppresses hippocampal theta oscillation in rabbits during EEG

In earlier studies it has been shown that stimulation of the median raphe nucleus (MR) in awake rabbits decreases the expression and frequency of oscillatory theta activity in the septohippocampal system, and the functional blockade of this nucleus evokes the regular and high-frequency theta rhythm. The present work was aimed at elucidation of serotoninergic influence of MR (which also contains cells of other chemical nature) to the septohippocampal system of theta activity. Serotonin reuptake blocker fluoxetine that increases brain serotonin level was applied. Hippocampal electroencephalogram was recorded in awake rabbits. Bilateral intracerebroventricular infusion of fluoxetine hydrochloride (Sigma, St. Louis; 15 micrograms in 5 microliters saline) in all cases reduced the rhythmic theta activity. In 15 of 18 (83.3%) of experiments the decrease in hippocampal theta oscillations was more than 50% of the control level. The theta band of the spectral density histogram decreased in the mean by 56 +/- 5.8% of the control level (from 10 to 93% in different experiments, p < 0.001). The mean latency of these changes was 3.5 +/- 0.11 minutes (2.9-4.1 min), the effect duration was 64 +/- 3.2 min (45.3-90 min). The mean frequency of the theta waves did not change as compared to the baseline and was equal to 5.25 +/- 0.5 Hz (4.5-6.5 Hz). The fluoxetine-induced reduction of the theta rhythm expression in hippocampus is the evidence of its inhibitory control by serotoninergic brain system. It is suggested that the increase of the frequency of hippocampal theta rhythm after the functional blockade of MR observed in our earlier experiments was the result of a release of the septohippocampal system from the influence of nonserotoninergic neurons (via glutamatergic reticular formation) and/or temporary cessation of the MR interaction with noradrenergic, dopaminergic and glutamate/aspartate systems.     

Dependence of effects of weak combined low-frequency variable and constant magnetic fields on the intensity of asexual reproduction of planarians Dugesia tigrina on the magnitude of the variable field

It was shown that the stimulating effect of weak combined magnetic fields (constant component 42 microT, frequency of the variable component 3.7 Hz) on the division of planarians depends on the amplitude of the variable component of the field. The effect is particularly pronounced at 40 (the main maximum), 120, 160, and 640 nT. Narrow ranges of effective amplitudes alternate in some cases with equally narrow ranges in which the system does not respond to he treatment. In the range of super weak amplitudes of the variable field (0.1 and 1 nT), the stimulating effect is poorly pronounced. The data obtained indicate the presence of narrow amplitude windows in the response of the biological systems to weak and super weak magnetic fields. In a special series of experiments, it was shown that the effect of fields on planarians is partially mediated via aqueous medium preliminarily treated with weak magnetic fields. It is noteworthy that in experiments with water treated with weak magnetic fields, there were no pronounced maxima and minima in the magnitude of the effect in the range of amplitude of the variable magnetic field from 40 to 320 nT.     

Evolution of recombination in "host-parasite" systems. Multilocus models

Evolution of the recombination system caused by antagonistic species interactions (host and parasite, for example) was studied. The genetic structure of host population as well as that of parasite is explicitly present in our models. The selection intensity depends on host's resistance and parasite's virulence, both controlled by polygenic systems. The rec-system dynamics was numerically studied using the genetic operators method. It is shown that high-recombination alleles of the rec-modificator can have a short-term selective advantage in both interacting populations simultaneously.     

Acid stress response in Helicobacter pylori

Four lactococcal abortive infection mechanisms were introduced into strains which were sensitive hosts for P335 type phages and plaque assay experiments performed to assess their effect on five lactococcal bacteriophages from this family. Results indicate that AbiA inhibits all five P335 phages tested, while AbiG affects phiP335 itself and phiQ30 but not the other P335 species phages. AbiA was shown to retard phage Q30 DNA replication as previously reported for other phages. It was also demonstrated that AbiG, previously shown to act at a point after DNA replication in the cases of c2 type and 936 type phages, acts at the level of, or prior to phage Q30 DNA replication. AbiE and AbiF had no effect on the P335 type phages examined.     

Complexity and Transition Management

This article presents a framework, transition management, for managing complex societal systems. The principal contribution of this article is to articulate the relationship between transition management and complex systems theory. A better understanding of the dynamics of complex, adaptive systems provides insight into the opportunities, limitations, and conditions under which it is possible to influence such systems. Transition management is based on key notions of complex systems theory, such as variation and selection, emergence, coevolution, and self-organization. It involves a cyclical process of phases at various scale levels: stimulating niche development at the micro level, finding new attractors at the macro level by developing a sustainability vision, creating diversity by setting out experiments, and selecting successful experiments that can be scaled up.