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For the zones of “risky farming” characteristic of the Far East of the Russian Federation, the natural production conditions of the region are an important problem in preparing the soil for further basic agricultural work. So, when carrying out early spring agricultural work, due to presence of a solid underlying layer in the form of permafrost, they shall be completed in operational terms no more than 10 days, until the permafrost base thaws and the soil has not lost its bearing capacity. In addition, due to the peculiarities of the relief, the soil does not thaw equally in depth everywhere, which reduces the quality of field work and harrowing, as the most common operation, namely. This article provides theoretical and experimental studies on the adaptation of a wheeled tractor as part of a machine-tractor unit (MTU) used in harrowing to natural production conditions by installing a device that automatically regulates the load on the working body of the disc harrow or on the propellers of the energy device, depending on the conditions of use or the state of the motion surface. more...

This article is a study devoted to the scientific direction that existed in the 30-40-s in the system of general pedagogy - pedology. The article examines the origins of interest in the scientific and comprehensive study of childhood, the history of the emergence and development of pedology abroad and in Russia. In this study, the emergence of pedology in Russia is interpreted by the authors as a response to the growing interest of social and humanitarian knowledge in the personality of the child and the spread of the ideas of humanism that came to Russia from the West. However, due to the prevailing social, political conditions, as well as objective reasons that are analyzed in the work, pedology was abolished and the interdisciplinary study of childhood was suspended for a long time. The presented material also provides an analytical overview of the main directions of the formation of pedology as an academic subject for pedagogical educational institutions in the period of the 30-s – 40-s. The sources used were educational programs and textbooks on pedology, works of pedologists of the 30-s – 40-s, articles from the journal “Pedology”, documents of the People's Commissariat of Education and archival materials. In addition, the article attempts to highlight the range of pedological problems relevant to the modern educational system. more...

The object of this study is the issue of introducing innovations into the process of preparing students of a higher education institution in the subject “Life Safety”. The authors set a goal to open and characterize the fundamental issues associated with the introduction of innovations in the educational process of a university in a particular subject based on a comprehensive systematic analysis of the process of preparing students in universities, as well as basic regulatory legal documents in the field of education and basic professional educational programs and curricula. Moreover, the authors rely not only on approaches and conclusions based on solidarity, but also alternative theoretical ones. The results obtained during the study made it possible to determine ways to solve the issues associated with the correlation of innovative approaches with the subject “Life Safety”. The novelty of the study and its results are determined by the original approach to identifying the characteristic features of innovations in the educational process and studying the systemic links between innovative forms, methods of the educational process and the content of the subject. more...

The article is devoted to the consideration of youth and youth policy as factors of terrorism in the 21st century. The authors have identified factors that increase the effectiveness of recruiters of terrorist organizations in attracting young people, as well as formulated and justified the principles of improving the effectiveness of youth policy in the framework of anti-terrorist activities of the authorities. According to the authors, an important factor in the radicalization of young people is the low level of education in the country. The authors draw attention to the fact that the low level of education does not create opportunities for the development of young people. This, in turn, leads to a radicalization of the relationship between the authorities and students. If graduates are unable to find jobs that meet their expectations, then the risk of radicalization of young people increases. A good education not only allows the state to train qualified specialists, which effectively affects the social and economic development of society. Specialists in demand do not belong to social groups prone to violent and radical actions in relation to other citizens, both within the country and abroad. Therefore, it is necessary, on the one hand, to develop educational programs that allow college and university graduates to be in demand in the labor market, constantly improve their skills, and increase the level of knowledge. On the other hand, it is necessary to develop students' skills, such as critical thinking, creativity, respect for the institutions of society, and skills in solving social and professional problems. [ABSTRACT FROM AUTHOR] more...

We describe a new caldera-volcano in the volcanic front of Kamchatka named Verkhneavachinskaya caldera (VC). According to geological mapping, the VC is interpreted as an eroded shield volcano with a summit caldera exposing 1 km-thick lava-like ignimbrites. It is one of the largest (10×12 km diameter) and oldest (c. 5.78-5.58 Ma, Ar-Ar dating) morphologically preserved paleovolcano in Kamchatka. The welded ignimbrites with fiammes are andesites-basaltic andesites in composition, they are more mafic than most ignimbrites worldwide and than other post-Pliocene calderas in Kamchatka. The deposits of VC are interbedded layers of welded ignimbrites and volcanoclastic material, which we interpret as result of long-lived volcanic center activity with hot pyroclastic flows and subsequent accumulations of volcanoclastic suites (e.g. lahars). The most trace element ratios in VC rocks (e.g. La/Yb, Nb/La, Ba/Th) show similarity with post-accretion magmatism at Kamchatka and especially with Late Pleistocene-Holocene Bakening volcano located in the same area. The VC provides new insights into the early stages of Kamchatka frontal zone development after the Kronotsky Arc Terrane accretion. This potentially explains the origin of voluminous basaltic-andesitic ignimbrites formed on thin crust during the initial stage of the arc formation. [ABSTRACT FROM AUTHOR] more...

Micromachined thermal infrared (IR) detectors are emerging into the marketplace to provide high-performance thermal (IR) imagery at low cost. Thermal detectors can be improved when a tunable wavelength response is provided and when a thermal chopper is incorporated into the detector by use of microelectromechanical (MEM) elements. Most thermal detectors require a chopper, continuous synchronous chopping in the case of pyroelectric detectors, or asynchronous chopping in the case of staring microbolometers. Mechanical choppers are bulky and costly. We present the fundamental principles of micromachined thermal detectors that possess tunable wavelength or color response and a technique for thermal chopping. A micromirror, switching between two spatial positions under the detector, provides a response to two wavelength windows by tuning the optical resonant cavity. The image can then be integrated at the readout level to achieve a multicolor IR picture. A thermal MEM chopper can be used instead of a mechanical chopper to maintain the same video frame rate and to allow for an interlaced resetting of staring thermal arrays. Unlike the second generation of uncooled IR arrays, the actual temperature of objects can be obtained by a comparison of the response in two wavelength windows, in addition to the direct measurement of IR power that they radiate in the entire 8-14-[micro]m spectral region. [C] 2001 Optical Society of America OCIS codes: 040.0040, 040.3060, 110.3080, 110.6820. more...

Two approaches to the chemoenzymatic synthesis of 2-fluorocordycepin and 2-chlorocordycepin were studied: (i) the use of 3'-deoxyadenosine (cordycepin) and 3'-deoxyinosine (3'dIno) as donors of 3-deoxy-D-ribofuranose in the transglycosylation of 2-fluoro-(2FAde) and 2-chloroadenine (2ClAde) catalyzed by the recombinant E. coli purine nucleoside phosphorylase (PNP), and (ii) the use of 2-fluoroadenosine and 3'-deoxyinosine as substrates of the cross-glycosylation and PNP as a biocatalyst. An efficient method for 3'-deoxyinosine synthesis starting from inosine was developed. However, the very poor solubility of 2ClAde and 2FAde is the limiting factor of the first approach. The second approach enables this problem to be overcome and it appears to be advantageous over the former approach from the viewpoint of practical synthesis of the title nucleosides. The 3-deoxy-a-D-ribofuranose-1-phosphate intermediary formed in the 3'dIno phosphorolysis by PNP was found to be the weak and marginal substrate of E. coli thymidine (TP) and uridine (UP) phosphorylases, respectively. Finally, one-pot cascade transformation of 3-deoxy-D-ribose in cordycepin in the presence of adenine and E. coli ribokinase, phosphopentomutase, and PNP was tested and cordycepin formation in ca. 3.4% yield was proved. [ABSTRACT FROM AUTHOR] more...

The electret consisting of a Si3N4 pattern on a SiO2 layer is studied. A charge pattern on 1.3 \mum-wide Si3N4 electret lines is successfully formed with a voltage of 80 V between charged pattern and substantially discharged SiO2. The method for making a charge pattern is optimized for reaching the highest voltage on narrow lines. A yearlong sample aging on open air shows that there is no dependence of charge retention on line width within the 1 cm–1.3 \mum range. Considering the decay of surface potential during 1 year, the estimated charge lifetime in the patterned electret exceeds 75 years. [ABSTRACT FROM PUBLISHER] more...

It is shown that the maximum surface potential in inorganic electrets is limited by the breakdown of the dielectric layer. It is observed that several composing layers contribute to charge trapping in multilayer electrets. The mean distance of charge from the substrate and the trap density are extracted. At least two dielectric layers are necessary for improving charge retention at elevated temperatures. The studied electrets are promising for applications and show a lifetime of over 10 years at a temperature of 200 °C [ABSTRACT FROM PUBLISHER] more...

The physics and basic properties of electrets are discussed, namely, what happens during corona charging of dielectrics, why the surface potential and trapped charge show certain limits, where the trapped charge is stored, why and how the charge is released from traps at high temperatures. The experiments have been conducted on single-layer SiO2 and Si3N4 and on multilayer combination of these materials. A strong lateral mobility of charge trapped near the SiO2/Si3N4 interface was observed at elevated temperatures. The positively and negatively charged electrets are compared to each other. The experiments on charge retention at elevated temperatures have shown the studied electrets are suitable for devices working at temperatures of up to 200-300°C. [ABSTRACT FROM AUTHOR] more...

In this paper, we present our vision of what kind of wearable devices and how they can be powered by the heat of human beings and by using ambient light. The basic principles of designing body-powered devices and ways of their hybridizing with photovoltaic cells are discussed. The mechanisms of thermoregulation in humans and the laws of thermodynamics enable placing a distinct boarder between realistic targets and the science fiction. These allow prediction of application areas for wearable energy harvesters accounting for competitive batteries with long service life. The existing family of body-powered wearable devices and new technologies for thermopiles are discussed. The theory and practice point at the necessity of using microelectronic and microelectromechanical system technologies for the target application area. These technologies for thermopiles offer the possibility of reduced production cost. Therefore, autonomous systems powered thermoelectrically could be successfully marketed. The related aspects of design and fabrication are discussed. [ABSTRACT FROM AUTHOR] more...

A high-precision wearable bioimpedance sensor developed at Imec was extensively tested. Unlike known bioimpedance sensors on the market, the new device enables hydration shift measurement in a single person, with no need for averaging over a population. For reaching this target, a method for hydration monitoring in case of altered hydration is tested. An assessment of fluid shift with sensitivity of about 700 ml has been demonstrated, which is comparable with the capabilities of known methods because of the device accuracy, immunity to electrode-skin impedance variation, and due to establishing the impedance baseline prior to fluid shift. more...