Bacterial Cellulose/Alginate Nanocomposite for Antimicrobial Wound Dressing

Development of novel wound dressing has attracted more and more attentions in recent years. Bacterial cellulose is a biopolymer of great potentials, which features a distinctive three-dimensional structure consisting of an ultrafine network of cellulos nanofibers. In the present study, nanocomposite bacterial cellulose films modified in situ by the addition of alginate during the static cultivation of Gluconacetobacter sucrofermentans B-11267 were produced and then enriching the polymer with an antimicrobial agent tetracycline hydrochloride. The structure of bacterial cellulose and nanocomposite was analyzed by AFM and FTIR. The FTIR spectra displayed the specified interaction between the hydroxyl group of cellulose and the carboxyl group of alginate. The produced bacterial cellulose and nanocomposite were analyzed to determine tensile modulus. The antibacterial activity of nanocomposites were investigated by disk diffusion method. The resulting nanocomposite have high antibiotic activity against Staphylococcus aureus and can be used in medicine as a wound dressing. Keywords: bacterial cellulose, Gluconacetobacter sucrofermentans, alginate, nanocomposite, antibacterial activity, wound dressin

Control of the enlisted potential of the higher school: problems and the prospects

In the article the problems of control of the enlisted potential of higher school in connection with the renovation of normative lawful reports in the sphere of labor, formation and science are examined. Some problems in the sphere of control of cadreresources and the regulation of the labor of pedagogical workers in the system of higher education are determined. Are designated the prospects of introducing the effective contract and the reasons, which impede its introduction.Рассматриваются вопросы управления кадровым потенциалом высшей школы в связи с обновлением нормативных правовых актов в сфере труда, образования и науки. Определены некоторые проблемы в сфере управления кадровыми ресурсами и регулирования труда педагогических работников в системе высшего образования. Обозначены перспективы внедрения эффективного контракта и причины, препятствующие его внедрению

Development of Internet communication and social networking in modern conditions: institutional and legal aspects

The development of the Internet, which has been active over the past two decades, is leading to the formation of new forms of human interaction on the World Wide Web. One of such forms is actually social networks, which from the beginning of their activity are used mainly as a way to ensure human communication. However, such a big number of consumers with the usual ways of buying goods and services, lead to the search for new platforms for companies to do business, which in turn provokes the transition of social networks to a fundamentally new level of activity

Vertical distribution of ¹³⁷Cs in alluvial soils of the Lokna River floodplain (Tula oblast) long after the Chernobyl accident and its simulation

© 2016, Pleiades Publishing, Ltd.Profiles of vertical 137Cs distribution in alluvial meadow soils on the low and medium levels of the Lokna River floodplain (central part of the Plavsk radioactive spot in Tula oblast) 28 years after the Chernobyl fallout have been studied. A significant increase in the 137Cs pool is revealed on the low floodplain areas compared to the soils of interfluves due to the accumulation of alluvium, which hampers the reduction of the total radionuclide pool in alluvial soils because of radioactive decay. The rate of alluvium accumulation in the soil on the medium floodplain level is lower by three times on average. An imitation prognostic model has been developed, which considers the flooding and climatic conditions in the region under study. Numerical experiments have quantitatively confirmed the deciding role of low-mobile forms in the migration of maximum 137Cs content along the soil profile in the absence of manifested erosion–accumulation processes

Ferroelectric nanocomposites based on polymer ferroelectrics and graphene/oxide graphene: Computer modeling and SPFM experiments

The authors are thankful to the Russian Science Foundation (RSF grant # 16-19-10112) and to the Russian Foundation for Basic Researches (RFBR grants # 16-51-53917) for support. Prof. Xiang-Jian Meng expresses his gratitude to the National Natural Science Foundation of China (NNSFC) for support of the project: "The study on the new type of infrared detector based on ferroelectric tunnel junction"

Piezoelectric, ferroelectric, optoelectronic and photo-catalytic phenomena from defect levels in hydroxyapatite by first-principles

The authors thank the Russian Foundation for Basic Researches (RFBR grant 19-01-00519 A) and to the Fundação para a Ciência e a Tecnologia (FCT) through project UID/CTM/50025/2013

Influence of liposome forms of rhenium-platinum anti-tumor system on the proliferative activity of cancer cells

Уперше показано антипроліферативну активність реній-платинової системи на клітинах раку крові людини СЕМ-Т4. Найефективнішими виявилися експерименти, де використовувались обидва компоненти системи. Показано також перевагу ліпосомних форм порівняно з розчинами препаратів та переважний апоптотичний механізм загибелі клітин під дією системи.Впервые показана антипролиферативная активность рений-платиновой системы на клетках рака крови человека СЕМ-Т4. Наиболее эффективными оказались эксперименты, где использовались оба компонента системы. Показано также преимущество липосомных форм в сравнении с растворами препаратов и преимущественный апоптотический механизм гибели клеток под действием системы.First the antiproliferative activity of the antitumor system rhenium-platinum on the human blood cancer cells СЕМ-Т4 was shown. Experimental administration of both components of the system showed the most effectiveness. The advantages of liposomic forms in comparison with preparations solutions and dominating apoptotic mechanism of the cancer cells death under the treatment by the system were shown

A new estimation of the recent tropospheric molecular hydrogen budget using atmospheric observations and variational inversion

This paper presents an analysis of the recent tropospheric molecular hydrogen (H2) budget with a particular focus on soil uptake and European surface emissions. A variational inversion scheme is combined with observations from the RAMCES and EUROHYDROS atmospheric networks, which include continuous measurements performed between mid-2006 and mid-2009. Net H2 surface flux, then deposition velocity and surface emissions and finally, deposition velocity, biomass burning, anthropogenic and N2 fixation-related emissions were simultaneously inverted in several scenarios. These scenarios have focused on the sensibility of the soil uptake value to different spatio-temporal distributions. The range of variations of these diverse inversion sets generate an estimate of the uncertainty for each term of the H2 budget. The net H2 flux per region (High Northern Hemisphere, Tropics and High Southern Hemisphere) varies between −8 and +8 Tg yr−1. The best inversion in terms of fit to the observations combines updated prior surface emissions and a soil deposition velocity map that is based on bottom-up and top-down estimations. Our estimate of global H2 soil uptake is −59±9 Tg yr−1. Forty per cent of this uptake is located in the High Northern Hemisphere and 55% is located in the Tropics. In terms of surface emissions, seasonality is mainly driven by biomass burning emissions. The inferred European anthropogenic emissions are consistent with independent H2 emissions estimated using a H2/CO mass ratio of 0.034 and CO emissions within the range of their respective uncertainties. Additional constraints, such as isotopic measurements would be needed to infer a more robust partition of H2 sources and sinks