Twisted speckle entities inside wavefront reversal mirrors

The previously unknown property of the optical speckle pattern reported. The interference of a speckle with an oppositely moving phase-conjugated speckle wave produces a randomly distributed ensemble of a twisted entities (ropes) surrounding optical vortex lines. These entities appear in a wide range of randomly chosen speckle parameters inside the phase-conjugating mirrors regardless to an internal physical mechanism of the wavefront reversal. These numerically generated interference patterns are relevant to a Brillouin $\bf PC$-mirrors and to a four-wave mixing $\bf PC$-mirrors based upon laser trapped ultracold atomic cloud.Comment: 4 pages,3 figures, Accepted to Physical Review

Laser in the axial electric field as a tool to search for P-, T- invariance violation

We consider rotation of polarization plane of the laser light when a gas laser is placed in a longitudinal electric field (10~kV/cm). It is shown that residual anisotropy of the laser cavity 10^{-6} and the sensitivity to the angle of polarization plane rotation about 10^{-11} -10^{-12} rad allows one to measure an electron EDM with the sensitivity about 10^{-30} e cm.Comment: 12 page

Solution to the Informatization Problem of Geographical Education in Schools on the Basis of Electronic Cartographical Training Manuals

Розглянуто електронні навчальні картографічні посібники як сучасні моделі представлення знань, сучасні технології розробки та функціональні можливості, проаналізовано новітні технічні досягнення у навчальному процесі. Розкрито основні вимоги до цього виду навчальної картографічної продукції, а також інноваційні педагогічні методи та прийоми, що забезпечують електронні картографічні посібники. Electronic cartographic training manuals are considered as modern model of knowledge representation, technology of their design and features is researched, the latest technological advances in the educational process are reviewed. Disclosure of the basic requirements for this type of training cartographic products, as well as new teaching methods and techniques that provide electronic cartographic materials.Роботу виконано на кафедрі геодезії, землевпорядкування і кадастру ВНУ ім. Лесі Українки та кафедрі геодезії і картографії КНУ ім. Т. Шевченк

Evolutionarily new sequences expressed in tumors

BACKGROUND: Earlier we suggested the concept of the positive evolutionary role of tumors. According to this concept, tumors provide conditions for the expression of evolutionarily new and/or sleeping genes in their cells. Thus, tumors are considered as evolutionary proving ground or reservoir of expression. To support this concept we have previously characterized in silico and experimentally a new class of human tumor-related transcribed sequences. RESULTS: In this article we describe results of further studies of previously described tumor-related sequences. The results of molecular phylogeny studies, Southern hybridization experiments and computational comparison with genomes of other species are presented. CONCLUSION: These results suggest that these previously described tumor-related human transcripts are also relatively evolutionarily new

Lifelong Negative Influence of School Violence on Children.

violence in the school environment is a constant concern for educators and parents and is a serious and often lifelong burden for the young victims. School violence is not just a limited problem, variously affecting specific or isolated communities in economic advantaged or disadvantaged areas, but a global modern phenomenon involving, to various degrees, one of the core social institutions of our society.The European Paediatric Association-Union of National European Paediatric Societies and Associations (EPA/UNEPSA), through the working group on social pediatrics, supported by its European national pediatric societies members, is currently developing dedicated projects to investigate the physical, psychological, and social impacts of school violence on European children and its possible lifelong risks. The purpose of this commentary is to raise awareness on this issue among healthcare professionals involved in childcare and to emphasize the importance of their participation in programs that are developed to monitor and prevent the negative, personal, and social impact

Creation, doubling, and splitting, of vortices in intracavity second harmonic generation

We demonstrate generation and frequency doubling of unit charge vortices in a linear astigmatic resonator. Topological instability of the double charge harmonic vortices leads to well separated vortex cores that are shown to rotate, and become anisotropic, as the resonator is tuned across resonance

Excitonic effects on the two-color coherent control of interband transitions in bulk semiconductors

Quantum interference between one- and two-photon absorption pathways allows coherent control of interband transitions in unbiased bulk semiconductors; carrier population, carrier spin polarization, photocurrent injection, and spin current injection may all be controlled. We extend the theory of these processes to include the electron-hole interaction. Our focus is on photon energies that excite carriers above the band edge, but close enough to it so that transition amplitudes based on low order expansions in $\mathbf{k}$ are applicable; both allowed-allowed and allowed-forbidden two-photon transition amplitudes are included. Analytic solutions are obtained using the effective mass theory of Wannier excitons; degenerate bands are accounted for, but envelope-hole coupling is neglected. We find a Coulomb enhancement of two-color coherent control process, and relate it to the Coulomb enhancements of one- and two-photon absorption. In addition, we find a frequency dependent phase shift in the dependence of photocurrent and spin current on the optical phases. The phase shift decreases monotonically from $\pi /2$ at the band edge to 0 over an energy range governed by the exciton binding energy. It is the difference between the partial wave phase shifts of the electron-hole envelope function reached by one- and two-photon pathways.Comment: 31 pages, 4 figures, to be published in Phys. Rev.

Simulating magnetic field of a ferromagnetic pipe underwater in COMSOL Multiphysics

Nowadays ecological situation in seas and oceans requires permanent supervision and control. Carrying out building activity such as building hydraulic structures, oil- and gas-pipes in areas of past warfare is the reason for the active usage of geophysical methods to search method of the objects underwater. The paper examines the classification of magnetic search methods and theoretical base statements of electromagnetics. The work represents the investigation of an object influence on geomagnetic field in problem-solving environment "COMSOL Multiphysics". The article also contains the results of simulating for variations of different object parameters. This paper is connected with the magnetometric