Domain evolution of BaTiO3 ultrathin films under electric field: a first-principles study

A first-principles-derived method is used to study the morphology and electric-field-induced evolution of stripe nanodomains in (001) BaTiO3 (BTO) ultrathin films, and to compare them with those in (001) Pb(Zr,Ti)O3 (PZT) ultrathin films. The BaTiO3 systems exhibit 180o periodic stripe domains at null electric field, as in PZT ultrathin films. However, the stripes alternate along [1-10] in BTO systems versus [010] in PZT systems, and no in-plane surface dipoles occur in BTO ultrathin films (unlike in PZT materials). Moreover, the evolution of the 180o stripe domains in the BaTiO3 systems, when applying and increasing an electric field along [001], involves four regions: Region I for which the magnitude of the down dipoles (i.e., those that are antiparallel to the electric field) is reduced, while the domain walls do not move; Region II in which some local down dipoles adjacent to domain walls switch their direction, resulting in zigzagged domain walls - with the overall stripe periodicity being unchanged; Region III in which nanobubbles are created, then contract along [110] and finally collapse; and Region IV which is associated with a single monodomain. Such evolution differs from that of PZT ultrathin films for which neither Region I nor zigzagged domain walls exist, and for which the bubbles contract along [100]. Discussion about such differences is provided.Comment: 19 pages, 4 figures, 27 references, submitted to Phys. Rev.

Instruments of investment attraction in order to fulfill the structural priorities of sustainable regional development (study based on the Rostov Region)

The aim of the study is devoted to defining most effective tools of investment funds attraction. These funds can be used in implementation of strategic priorities for socio-economic regional development requiring, in areas that are in need of economic restructuring. The authors have selected the Rostov region as the research target, the economy of which is in need of structural change in the direction of increasing innovational, high-tech and scientific production, in order to reduce import dependency and move closer towards the post-industrial model of economic development. The study considers currently available instruments of attraction of private sector closer to solving the stated problems of Rostov region, analyzing their regulatory, financial and organizational consulting security on both state and federal level. Main directions of economic restructuring of Rostov region are also defined. Authors also outline the main problems that private enterprises come across while doing business in the investigated area. On the basis of the research, investigating federal and regional instruments of private sector involvement authors form a number of proposals and recommendations focusing on regional improvement. As a result of the conducted study, the authors reached the conclusion, that there is a number of strategic measures that should be performed in the Rostov region. These don't only include the improvement of financial instruments, but also best available technologies, national technology initiative, and clustering.peer-reviewe

AI MENTORING AS A FORM AKMEOLOGICHESKOJ ORIENTED PROFESSIONAL INTERACTION

Optimization of professional relationships in the "mentor- apprentice" promotes the formation of a professional orientation akmeologicheskoj both subjects interaction. On the one hand , mentoring is one of the oldest and most effective ways to acquire knowledge and skills of young employees of the company in the process of adapting to a new team . On the other - allows teacher to identify their professional and personal opportunities and consciously decide to choose the optimum time of interaction with the students, based on their individual characteristics, as well as improve their own skills.Оптимизация профессиональных взаимоотношений в системе «наставник – ученик» способствует формированию акмеологической профессиональной направленности у обоих субъектов взаимодействия. Наставничество является одним из самых старых и эффективных способов приобретения знаний и навыков молодыми сотрудниками предприятия в процессе их адаптации в новом коллективе; позволяет наставнику выявить свои профессионально-личностные возможности и осознанно определиться в выборе оптимального стажа взаимодействия с учениками, с учетом их индивидуальных особенностей, а также повысить уровень собственного мастерства

Underestimated risks of recurrent long-range ash dispersal from northern Pacific Arc volcanoes

Widespread ash dispersal poses a significant natural hazard to society, particularly in relation to disruption to aviation. Assessing the extent of the threat of far-travelled ash clouds on flight paths is substantially hindered by an incomplete volcanic history and an underestimation of the potential reach of distant eruptive centres. The risk of extensive ash clouds to aviation is thus poorly quantified. New evidence is presented of explosive Late Pleistocene eruptions in the Pacific Arc, currently undocumented in the proximal geological record, which dispersed ash up to 8000?km from source. Twelve microscopic ash deposits or cryptotephra, invisible to the naked eye, discovered within Greenland ice-cores, and ranging in age between 11.1 and 83.7 ka b2k, are compositionally matched to northern Pacific Arc sources including Japan, Kamchatka, Cascades and Alaska. Only two cryptotephra deposits are correlated to known high-magnitude eruptions (Towada-H, Japan, ca 15 ka BP and Mount St Helens Set M, ca 28 ka BP). For the remaining 10 deposits, there is no evidence of age- and compositionally-equivalent eruptive events in regional volcanic stratigraphies. This highlights the inherent problem of under-reporting eruptions and the dangers of underestimating the long-term risk of widespread ash dispersal for trans-Pacific and trans-Atlantic flight route

Development of Intelligent Interface to Input and Edit Meteorological Data

The paper presents the method of development of user interface for the hydrometeorological data acquisition system. This research includes some basic principles of creating hydrometeorological messages according to code KN-01 SYNOP. This code allows creating messages as a set of code groups. Every group keeps values of definite meteorological properties. The result of studies was implemented in creating of the user interface for the software that allows working with hydrometeorological data. The KN-01 code defines the class hierarchy of this software. The studies have shown that this method of software development is especially effective for visualization of the meteorological telegrams on devices with small display

Atomistic simulations of self-trapped exciton formation in silicon nanostructures: The transition from quantum dots to nanowires

Using an approximate time-dependent density functional theory method, we calculate the absorption and luminescence spectra for hydrogen passivated silicon nanoscale structures with large aspect ratio. The effect of electron confinement in axial and radial directions is systematically investigated. Excited state relaxation leads to significant Stokes shifts for short nanorods with lengths less than 2 nm, but has little effect on the luminescence intensity. The formation of self-trapped excitons is likewise observed for short nanostructures only; longer wires exhibit fully delocalized excitons with neglible geometrical distortion at the excited state minimum.Comment: 10 pages, 4 figure

Unadapted and adapted to starvation Acholeplasma laidlawii cells induce different responses of Oryza sativa, as determined by proteome analysis

For the first time, we studied the phytopathogenicity toward Oryza sativa L. of unadapted and adapted to unfavorable environment (starvation) cells of Acholeplasma laidlawii PG8 - ubiquitous mycoplasma found in the soil, waste waters, tissues of the highest eukaryotes and being the basic contaminant of cell cultures and a causative agent of phytomycoplasmoses. The features of morphology, ultrastructural organization and proteomes of unadapted and adapted cells of the mycoplasma and infected plants were presented. Using 2D-DIGE and MS, 43 proteins of O. sativa L. that were differentially expressed in the leaves of plants cultivated in media with A. laidlawii PG8 were identified. The qualitative and quantitative responses of the plant proteome toward adapted and unadapted mycoplasma cells differed. That may be explained by differences in the virulence of the corresponding bacterial cells. Using 2D-DIGE and MS, 82 proteins that were differentially expressed in adapted and unadapted mycoplasma cells were detected. In adapted cells of the mycoplasma, in comparison with unadapted ones, a significant increase in the expression of PNPase - a global regulator of virulence in phytopathogenic bacteria occurred; there was also decreased expression of 40 proteins including 14 involved in bacterial virulence and the expression of 31 proteins including 5 involved in virulence was not detected. We propose that differences in the phytopathogenicity of adapted and unadapted A. laidlawii PG8 cells may be related to features of their proteomes and membrane vesicles. © 2011 Elsevier B.V