MEASUREMENT OF LATERAL DIFFUSION IN LIPIDS

Different techniques to study lateral diffusion of lipids are reviewed, including long-range diffusion methods and short-range diffusion methods. Long-range diffusion methods require the measurements of the time needed to fill a given area of the membrane. Applications of fluorescence recovery after photobleaching (FRAP) method are discussed. Short-range diffusion methods measure the rate of bimolecular collisions. The methods include fluorescence quenching, fluorescence energy transfer, nuclear magnetic resonance and electron spin resonance spectroscopy. Special attention is given to Electron Spin Resonance (ESR) spectroscopy. Procedure of obtaining diffusion coefficient D using novel two dimensional electron double-double resonance experiment (2D-ELDOR) is discussed in greater detail. In order to demonstrate the feasibility of using 2D Fourier Transform ESR spectroscopy for lateral diffusion studies, the D of spin-labeled phospholipids sample is estimated by 2D-ELDOR method

Personalization of learning through adaptive technologies in the context of sustainable development of teachers education

The article highlights the issues of personalized learning as the global trend of the modern ICTbased educational systems development. The notion, the main stages of evolution, the main features and principles of adaptive learning systems application for teachers training are outlined. It is emphasized that the use and elaboration of the adaptive cloud-based learning systems are essential to provide sustainable development of teachers education. The current trends and peculiarities of the cloud-based adaptive learning systems development and approach of their implementation for teachers training are considered. The general model of the adaptive cloud-based learning system structure is proposed. The main components of the model are described; the issues of tools and services selection are outlined. The methods of the cloudbased learning components introduction within the adaptive systems of teacher training are considered. The current research developments of modeling and implementation of the adaptive cloud-based systems are outlined.Comment: 8 pages, 2 figures, E3S Web of Conferences (166). ISSN 2267-124

Персоналізація навчання за допомогою адаптивних технологій в контексті сталого розвитку освіти вчителів

The article highlights the issues of personalized learning as the global trend of the modern ICTbased educational systems development. The notion, the main stages of evolution, the main features and principles of adaptive learning systems application for teachers’ training are outlined. It is emphasized that the use and elaboration of the adaptive cloud-based learning systems are essential to provide sustainable development of teachers’ education. The current trends and peculiarities of the cloud-based adaptive learning systems development and approach of their implementation for teachers’ training are considered. The general model of the adaptive cloud-based learning system structure is proposed. The main components of the model are described; the issues of tools and services selection are outlined. The methods of the cloudbased learning components introduction within the adaptive systems of teacher training are considered. The current research developments of modeling and implementation of the adaptive cloud-based systems are outlined.У статті висвітлюються питання персоналізованого навчання як глобальної тенденції розвитку сучасних освітніх систем на базі ІКТ. Окреслено поняття, основні етапи еволюції, основні особливості та принципи застосування адаптивних систем для навчання вчителів. Підкреслюється, що використання та розробка адаптивних хмарних систем навчання є важливими для забезпечення сталого розвитку освіти вчителів. Розглянуто сучасні тенденції та особливості розвитку хмарних адаптивних систем навчання та підхід їх впровадження для навчання вчителів. Запропонована загальна модель структури адаптивної хмарної системи навчання. Описано основні компоненти моделі; окреслено питання вибору інструментів та послуг. Розглянуто методи впровадження компонентів навчання у хмарному середовищі в адаптивних системах навчання вчителів. Окреслено сучасні розробки в галузі моделювання та впровадження адаптивних хмарних систем

Asymmetric Membranes Based on Copolyheteroarylenes with Imide, Biquinoline, and Oxazinone Units: Formation and Characterization

Modern ultrafiltration requires novel perfect membranes with narrow pore size, high porosity, and minimal pore tortuosity to achieve high separation performance. In this work, copolyamic acid (co-PAA) was synthesized and used for the preparation of asymmetric porous membranes by phase inversion technique. Several co-PAA membranes were heated up to 250 °C; during heating, they undergo solid-phase transformation into co-polybenzoxazinoneimide (co-PBOI) via dehydration and cyclization. Comparative characterization of both co-PAA and co-PBOI membranes was realized by scanning electron microscopy, mechanical testing, thermogravimetric analysis, and ultrafiltration experiments. Membrane calibration was carried out using a mixture of seven proteins with different molecular weights. During heat treatment, the molecular weight cut-off of the membranes decreased from 20 × 103 g/mol (co-PAA) to 3 × 103 g/mol (co-PBOI). Abnormally low dispersions of rejection (0.3 for co-PAA and 0.45 for co-PBOI) were observed for the studied membranes; this fact indicates that the membranes possess enhanced resolving power.This work was funded by the Russian Science Foundation (RSF) [grant 16-13-10164]

Both helix topology and counterion distribution contribute to the more effective charge screening in dsRNA compared with dsDNA

The recent discovery of the RNA interference mechanism emphasizes the biological importance of short, isolated, double-stranded (ds) RNA helices and calls for a complete understanding of the biophysical properties of dsRNA. However, most previous studies of the electrostatics of nucleic acid duplexes have focused on DNA. Here, we present a comparative investigation of electrostatic effects in RNA and DNA. Using resonant (anomalous) and non-resonant small-angle X-ray scattering, we characterized the charge screening efficiency and counterion distribution around short (25 bp) dsDNA and RNA molecules of comparable sequence. Consistent with theoretical predictions, we find counterion mediated screening to be more efficient for dsRNA than dsDNA. Furthermore, the topology of the RNA A-form helix alters the spatial distribution of counterions relative to B-form DNA. The experimental results reported here agree well with ion-size-corrected non-linear Poisson–Boltzmann calculations. We propose that differences in electrostatic properties aid in selective recognition of different types of short nucleic acid helices by target binding partners

Archaeological collections from Isker: а new view on the significant site

Isker is the capital of the Siberian khanate at the initial stage (1582–1584) of the Russian conquest of Western Siberia. After Tobolsk was founded in 1587, Isker was abandoned. In the XVIII–XX centuries numerous amateur excavations were carried out on its territory, which, along with a natural factor (the River Irtysh washed out the part of a rock terrace where the ancient settlement is located) led to a severe destruction of the site. Professional archaeological researches were carried out only at the end of the XX century; however, they didn't give any significant result. All earlier collected collections were partially lost by the beginning of the XXI century. Th importance and status of the city in the Siberian khanate are still not defined. In this regard there was a need for an in-depth study of the available materials in order to understand specific characteristics of this complex and its place among other archaeological monuments of that time. This article represents in detail the results of an analysis of two collections of archaeological artifacts, which were collected in Isker by N.I. Butakov in 1896 and by A.F. Palashenkov in 1938 and which are stored in Omsk State Regional Historical Museum. The following groups of subjects were analyzed in detail: ceramics as the main marker of belonging of the Isker population to the Turkic Tatar society of Siberia of the XVI century; fighting and throwing knives; metal and bone arrowheads and bow plates; fragments of fishing tackles; locks and handles of storage chests; accessories; imported items. In general, it should be noted that composition of this complex of items does not differ from similar Tatar monuments of the period. Basing on the archaeological material, it is possible to conclude that the residents of the ancient settlement had a rather high social status, which is testified by the types of items (porcelain ware, bronze mirrors, rings, etc.) and high technology of their production. However it doesn't give the grounds to believe that the city was the constant capital of the Siberian khanate. Perhaps, it was only one of temporary headquarters of the khan. This research shows ambiguity in interpretation of the role of Isker in the Siberian khanate, and, therefore, it is important in terms of studying medieval Turkic-Tatar state