A Study of the Mechanism of Action of Zervamicin IIB Peptide Antibiotic by Molecular Dynamics Simulation

We model mechanism of action of a channel-forming peptide antibiotic, zervamicin IIB, by molecular dynamics (MD) simulation. Interaction of this peptide with neutral and negatively charged lipid bilayers is investigated. It is found that charge of membrane surface influences the orientation of zervamicin IIB molecule, that may in turn effect its permeation into the membrane. On this basis we propose modifications to ZrvIIB structure that may increase its affinity towards the prokaryotic cellular membrane. Zervamicin IIB transmembrane channels are modeled as bundles consisting of 4, 5 and 6 individual peptide monomers. Our results suggest that four monomers don’t form a stable water-filled ion channel. Thus the channel with the least number of monomers (and the lowest conductance level by literature data) is a pentamer

The path similarity method for phase measurements disambiguation

We introduce the technique for phase measurements disambiguation based on the paths similarity identification. To obtain these paths, we use phase and amplitude measurements. By simulation, the performance of the presented approach is established. Its application for the phase measurements disambiguation is demonstrated by the example of the phase correlative direction finder for which the amplitude correlative direction finding mode is activated without any hardware changes

Digital simulators of the random processes

The proposed universal digital simulators of random processes based on their Markov models are considered as capable of generating sequences of samples of unlimited duration. It is shown that a simple Markov chain allows generating the random numbers with a specified two-dimensional probability distribution of the neighboring values while a doubly connected Markov model makes it possible to get the three-dimensional random numbers. The parameters of the model are determined from either a known probability density or experimental samples of the simulated random process. It is demonstrated that the simulation algorithms do not require complex mathematical transformations and that they can be implemented using a simple element base. To change the properties of the generated random processes one needs to reload the memory device with a preformed data array. The block diagrams of the simulators are studied and the probabilistic and correlation characteristics of the generated random processes are determined. It is established that with these simulators a high accuracy of convergence of the probability distributions of the selected model and the histograms of the generated sample sequences is ensured. In the common studies, one can hardly find the results that can surpass by their efficiency the ones that the proposed simulation algorithms demonstrate accounting for their non-problematic hardware implementation (the minimum computational costs) and the simplicity of reconfiguring the Markov model based simulators for generating new random processes. The introduced simulators can be used in the design, development and testing of the multi-purpose electronic equipment, with different meters and the devices for simulating radio paths

Measurements of the total column amount of NO2 at Kislovodsk Observatory in 1979 - 1990

The results of the measurements of the NO2 total content at the 'Kislovodsk' observatory (North Caucasus 2070 m a.s.l.) in 1979-1990 are presented. The measurements were based on the absorption of the direct sunlight in the visible region of the spectrum. The variation of the NO2 content from the morning to the evening and the seasonal and year to year variations are analyzed. The less amplitude of the daily variations of the NO2 total content in comparison with the variations of the stratospheric NO2 content says about the significant insert of the tropospheric and lower stratospheric NO2 in its total content. The year to year variations of NO2 and ozone are in antiphase. Their values depends on the regional features of the atmospheric circulation. The quasibiennial oscillations of the total NO2 content are picked out

The Use of Umbilical Cord Blood Nucleated Cells in the Treatment of Regressive Autism: A Case Report

BACKGROUND: Interest in the issue of childhood autism has surged in the recent decades. At the same time, despite the significant progress achieved in understanding the etiological and pathogenetic aspects of the condition, effective ways to treat it have continued to elude us. Stem cell therapy appears to hold great promise in the treatment and rehabilitation of patients with both neurological diseases (cerebral palsy, hydrocephalus) and mental disorders (autism, schizophrenia). METHODS: This article presents a case report describing the use of nucleated cord blood cells in a patient with regressive autism and resistance to standard therapies. The child’s condition was assessed before treatment and 6 and 12 months after. RESULTS: Clinical observation, psychometric, and instrumental diagnostic methods led to a significant improvement in the child’s condition in the form of perception development, reduction of somatosensory disorders, normalization of emotional status, and a development of social and communication skills. CONCLUSION: We assume that the result obtained may be associated with the normalization of the immunological status of our patient thanks to the cord blood cells therapy and consider it necessary to conduct further studies into the effectiveness of the method, taking the pathogenic mechanisms of autism into account