961 research outputs found
Формування інформаційно-освітньо-виховного простору міста на основі розвитку партнерських взаємовідносин
Уточнено зміст термінів інформаційного та інформаційно-освітнього просторів.
Запропоновано поняття єдиного інформаційно-освітньо-виховного простору міста для його соціального розвитку на основі економічного зростання за рахунок активізації партнерських взаємовідносин різних соціально-економічних інституцій. Визначено основні вимоги до його формування. Запропоновано доповнити перелік платних послуг, які можуть надаватися навчальними закладами, послугами у сферах освітньої, наукової, науково-технічної діяльності
Features of accumulation of sulfur and phosphorus by phytoremediants from technogenically polluted wastewater of mining enterprises
The article presents data on the accumulation of phosphorus and sulfur in the tissues of phytoremediant plants Phragmites australis (Cav.) Trin. ex Steud., Typha angustifolia L., Typha latifolia L., used for the treatment of technogenically polluted wastewater from mining enterprise
Lyophilisation of bacterial test strains in a manifold-type apparatus: Effects of freezing and drying parameters, ampoule fill volume, and cotton filter density
Scientific relevance. Lyophilisation is the preferred method at the National Collection of Pathogenic Microorganisms (NCPM) of the Scientific Centre for Expert Evaluation of Medicinal Products of the Ministry of Health of the Russian Federation. Lyophilisation is used to provide for high standards of test-strain deposition, storage, and transportation and to ensure that test strains maintain their properties. Successful lyophilisation requires conducting experiments to establish the key parameters and critical conditions of the process.Aim. The study aimed to evaluate the effects that the speed and time of freezing, the time of drying, the fill volume of ampoules, and the density of cotton filters have on the quality of NCPM indicator microorganisms lyophilised in a manifold-type apparatus.Materials and methods. Pseudomonas aeruginosa NCTC 12924, Staphylococcus aureus NCTC 10788, and Salmonella Abony NCTC 6017 were freeze-dried using a manifold-type apparatus (M. S. R. 18, Usifroid). The authors used a low-temperature freezer at –70±2 °C for slow freezing and a mixture of dry ice and alcohol for quick freezing. The statistical analysis was performed using Microsoft Excel and Statistica 10.Results. The minimum time needed for freezing the samples in a low-temperature freezer at –70±2 °C was 4 hours. Further storage at this temperature for up to 1 month was shown possible without compromising the quality of the final product. The time needed for freezing the samples in a mixture of dry ice and alcohol was under 1 minute. No differences in quality parameters were observed between the lyophilised samples frozen slowly or quickly, except for the cake appearance. Quick freezing resulted in cakes that were non-uniform, crumbled, and pulled away from the ampoule walls, which is considered undesirable. The primary drying stage for ampoules with a fill volume of 0.2 mL took 6–8 hours. The secondary drying stage of 11, 18, 35, and 59 hours resulted in comparable lyophilisate quality: the authors observed no statistically significant differences in viable cell counts (CFU/mL) at the end of lyophilisation and at the end of stress testing. The residual moisture content after 59-hour secondary drying was less than 2%. The cotton filter density had a critical influence on the lyophilisate quality. Therefore, the authors recommend using cotton filters weighing 50 mg or less.Conclusions. The authors analysed the main stages of the lyophilisation process used for NCPM test strains and considered the effects that the speed and time of freezing, the time of drying, the fill volume of ampoules, and the density of cotton filters have on the quality of the final lyophilised product. The NCPM has implemented the results of this study in its work
Influence of the material of weighing bottles on loss-on-drying reproducibility
One of the factors influencing the uncertainty of residual moisture measurements in biological medicinal products is the accumulation of electrostatic charge on the surfaces of weighing bottles and laboratory balances, which results in poor weighing reproducibility. The authors believe that the simplest and most economical solution to this problem is to use weighing bottles made of a conductive material, e.g. metal. The aim of the work was to evaluate the influence of the material of weighing bottles on the reproducibility of loss-on-drying (LOD) methods. Materials and methods: Model samples for the study were prepared from a sucrose-gelatin medium by lyophilisation and subsequent moisture sorption to achieve a certain residual moisture content. The authors assessed the samples’ mass uniformity using Shewhart’s X-charts, and analysed their residual moisture content using a loss-on-drying procedure with glass and metal weighing bottles. Statistical processing of the results was carried out by calculating the main statistical indicators: Student’s t-test and Fisher’s F-test. Results: Four batches of model samples were prepared and standardised in terms of average mass using Shewhart’s charts. The effect of weighing bottle materials was most pronounced at low residual moisture contents (less than 0.5%), with the relative standard deviation (RSD) values for the results obtained with glass and metal weighing bottles reaching 76% and 35%, respectively. For the samples with a higher residual moisture content (2–5%), the minimum RSDs with glass and metal weighing bottles were 15% and 6%, respectively. Conclusions: The study allowed for evaluating the influence of the material of weighing bottles on the results of LOD measurements and demonstrated a higher reproducibility with metal weighing bottles. This confirms the possibility of using metal weighing bottles in quality assessment of biological medicinal products for human use with LOD methods
Bremsstrahlung in the gravitational field of a cosmic string
In the framework of QED we investigate the bremsstrahlung process for an
electron passing by a straight static cosmic string. This process is precluded
in empty Minkowski space-time by energy and momentum conservation laws. It
happens in the presence of the cosmic string as a consequence of the conical
structure of space, in spite of the flatness of the metric. The cross section
and emitted electromagnetic energy are computed and analytic expressions are
found for different energies of the incoming electron. The energy interval is
divided in three parts depending on whether the energy is just above electron
rest mass , much larger than , or exceeds , with the
string mass per unit length in Planck units. We compare our results with those
of scalar QED and classical electrodynamics and also with conic pair production
process computed earlier.Comment: 21 pages, to appear in Phys. Rev. D., KONS-RGKU-94-0
Recycling and disposal of gypsum-containing waste generated in the production of citric acid
The cycle of citric acid production with the formation of gypsum-containing waste was considered and options for processing and utilization of citrogypsum were proposed. The methods obtained include: the use of citrogypsum in the production of building materials, the extraction of rare earth metals, as well as the creation of a high-quality organic-mineral fertilizer, during the creation of which it is possible to reduce the negative effect not only from the accumulation of citrogypsum, but also from manure stored in the filtration field
A Precision Measurement of Nuclear Muon Capture on 3He
The muon capture rate in the reaction mu- 3He -> nu + 3H has been measured at
PSI using a modular high pressure ionization chamber. The rate corresponding to
statistical hyperfine population of the mu-3He atom is (1496.0 +- 4.0) s^-1.
This result confirms the PCAC prediction for the pseudoscalar form factors of
the 3He-3H system and the nucleon.Comment: 13 pages, 6 PostScript figure
The Review of Anthrax Situation 2013, the Forecast for 2014
The analysis of epidemiological and epizootiological situation on anthrax in the Russian Federation and in the world in 2013 is carried out. The forecast of disease for 2014 is presented. Anthrax morbidity in humans in Russia is shown to decrease in 2013 in comparison with that in 2012 (2 cases versus 12). Three anthrax cases are registered in cattle
Evaluation of Anthrax Morbidity Rate in 2012, Prognosis for 2013
Evaluated are epidemiological and epizootiological situations on anthrax in the Russian Federation and around the world in 2012. Displayed is the morbidity rate prognosis for 2013
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