262 research outputs found
Influence of distortions of key frames on video transfer in wireless networks
In this paper it is shown that for substantial increase of video quality in
wireless network it is necessary to execute two obligatory points on
modernization of the communication scheme. The player on the received part
should throw back automatically duplicated RTP packets, server of streaming
video should duplicate the packets containing the information of key frames.
Coefficients of the mathematical model describing video quality in wireless
network have been found for WiFi and 3G standards and codecs MPEG-2 and MPEG-4
(DivX). The special experimental technique which has allowed collecting and
processing the data has been developed for calculation of values of factors.Comment: 6 pages, 4 figures, 2 Table
Heat effects of dehydration of human serum albuminin hydrophilic organic solvents
A thermochemical model for describing the transfer of water from the protein phase to the organic solvent liquid phase and for determining how the solvation ability of organic solvents affects this process was developed. Enthalpy changes on the interaction of dried and hydrated human serum albumin (HSA) with hydrophilic organic solvents (dimethyl sulfoxide, formamide, ethanol, methanol and acetic acid) and water were measured by isothermal calorimetry at 25°C. The initial hydration level of human serum albumin was varied in the entire water content range from 0-30% g water/g HSA. The dependence of the interaction enthalpies on the initial water content is complex. The interaction enthalpies of the dried HSA with organic solvents are exothermic. At low water contents (less than 0.1 g/g), there is a sharp increase in the interaction enthalpy values. At the highest water contents (more than 0.2 g/g), the interaction enthalpies are endothermic for acetic acid and formamide and exothermic for DMSO, methanol, and ethanol. These thermochemical data were analyzed in conjunction with the results for the water adsorption in organic solvents to calculate the molar enthalpies of dehydration of HSA in organic liquids. It was found that the dehydration enthalpy changes may be endothermic or exothermic depending on the initial water content and the water solvation enthalpy value. From the results obtained, it can be concluded that: (i) only the solvation of water by hydrophilic organic solvent determines the changes in the dehydration enthalpy values, and (ii) the data for the enthalpies of solvation of water by the solvent at infinite dilution reflect this effect. © Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
A new humic acid remedy with addition of silver nanoparticles
Previously known biogenic stimulator humic acid (HA) was the subject of this current study and HA based new remediation was developed by addition of silver (Ag) nanoparticles in its macromolecule. Extracted HA from a healing mud was characterized and used as reducing agent for Ag ion as well as a stabilizer for the formed Ag nanoparticles. The properties of the obtained hybrid composite were examined by XRD, UV and FTIR spectroscopic techniques. The diameter of the nanoparticles in the HA polymer was up to 8.6 nm and they were identified to be metallic Ag.DOI: http://dx.doi.org/10.5564/mjc.v13i0.151 Mongolian Journal of Chemistry Vol.13 2012: 7-1
Russian retail ESG transformations development
The article analyse the formation of the sustainable development paradigm and the ESG agenda in Russia. The activities of the largest Russian retailers: leaders in sustainable development and companies with a weaker position in this area is revealed. The relationship between the form of the company and its position in the ESG ratings has been noted. Thus, companies that are required to provide information publicly are higher in level than non-public ones. A characteristic feature of passing the ESG rating assessment is getting high scores in terms of the G-aspect and the E-aspect associated with the demands of the modern market. The authors recommended deepening activities in the field of sustainable development in terms of training employees in digital and environmental competencies, and to strengthen communication strategies regarding the ESG agenda of the largest retailers
Анализ причин поздней диагностики туберкулеза легких
A pilot study was designed to analyze causes of late diagnosis of lung tuberculosis and late start of the specific therapy. Thirty-eight inpatients with proven infiltrative lung tuberculosis were randomly involved in the study; they were city and rural dwellers of different age. A special questionnaire was developed to determine reasons of late diagnosis. An analysis of results obtained has shown that 8 patients, or 21 % were diagnosed at a scheduled large frame photofluorography, 30 % of the late diagnosed patients were not aware of their disease, 25 % of the females and 64 % of the maleswere self-treated. Primary care therapeutists were blamed for the late diagnosis in 33 % of the patients while failed to perform necessary investigations; the delay was 2 to 11 months.Было проведено пилотное исследование по анализу причин отсрочки установления диагноза туберкулез легких (ТЛ) и начала специфической терапии. Методом случайной выборки было взято 38 пациентов с подтвержденным диагнозом инфильтративный ТЛ, проходивших курс стационарного лечения, жителей городской и сельской местности, различного возраста. Для установления причин отсрочки была разработана специальная анкета. Анализ порученных результатов показал, что у 8 пациентов (21 %) патология была выявлена при плановой ККФ. 30 % пациентов с отсрочкой диагноза не располагают информацией о туберкулезе, 25 % женщин и 64 % мужчин проводили самолечение. У 33 % обследованных отсрочка диагноза и начала лечения произошла по вине участкового терапевта, из-за невыполнения диагностического минимума обследования на туберкулез, она составила от 2 до 11 месяцев
Discrete structure of ultrathin dielectric films and their surface optical properties
The boundary problem of linear classical optics about the interaction of
electromagnetic radiation with a thin dielectric film has been solved under
explicit consideration of its discrete structure. The main attention has been
paid to the investigation of the near-zone optical response of dielectrics. The
laws of reflection and refraction for discrete structures in the case of a
regular atomic distribution are studied and the structure of evanescent
harmonics induced by an external plane wave near the surface is investigated in
details. It is shown by means of analytical and numerical calculations that due
to the existence of the evanescent harmonics the laws of reflection and
refraction at the distances from the surface less than two interatomic
distances are principally different from the Fresnel laws. From the practical
point of view the results of this work might be useful for the near-field
optical microscopy of ultrahigh resolution.Comment: 25 pages, 16 figures, LaTeX2.09, to be published in Phys.Rev.
Species substrate specificity of growth of lactobacilli isolated from vaginal biotope on culture medium with inclusions of different types of natural nanopolysaccharides
The article presents the research of substrate and prebiotic properties of natural nanopolysaccharides for several species of lactobacilli isolated from vaginal biotope of women, with assessment of their species combinations. Most of typeable lactobacilli species prefer to grow on media containing polysaccharides, mainly in nutrient broth supplemented with galactomannan and carageenan. Using galactomannan increases the frequency of detection, as compared with the isolation from the starting material, twice
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