INTRA-OCEANIC ARCS OF THE PALEO-ASIAN OCEAN

Intra-oceanic arcs (IOAs) form at Pacific-type convergent margins, in the upper “stable” plate, when the subducting plate submerges to the depths of melting, i.e., to ca. 50–100 km. A typical IOA system, such as Mariana-Bonin and the Philippines Sea, consists of subduction zone, fore-arc region with accretionary prism, frontal or active arc, marginal basin with spreading center, and, in some cases, one or more remnant arcs and inactive marginal basin. The IOAs are very important elements of Pacific-type convergent margins as they represent major sites of juvenile continental crust formation (e.g. [Clift et al., 2003; Stern, 2010; Maruyama et al., 2011]), but are also the most important sites of crust removal by sediment subduction and tectonic/ subduction erosion [Stern, Scholl, 2010].Intra-oceanic arcs (IOAs) form at Pacific-type convergent margins, in the upper “stable” plate, when the subducting plate submerges to the depths of melting, i.e., to ca. 50–100 km. A typical IOA system, such as Mariana-Bonin and the Philippines Sea, consists of subduction zone, fore-arc region with accretionary prism, frontal or active arc, marginal basin with spreading center, and, in some cases, one or more remnant arcs and inactive marginal basin. The IOAs are very important elements of Pacific-type convergent margins as they represent major sites of juvenile continental crust formation (e.g. [Clift et al., 2003; Stern, 2010; Maruyama et al., 2011]), but are also the most important sites of crust removal by sediment subduction and tectonic/ subduction erosion [Stern, Scholl, 2010]

Degeneracy in exotic gravitational lensing

We present three different theoretically foreseen, but unusual, astrophysical situations where the gravitational lens equation ends up being the same, thus producing a degeneracy problem. These situations are (a) the case of gravitational lensing by exotic stresses (matter violating the weak energy condition and thus having a negative mass, particular cases of wormholes solutions can be used as an example), (b) scalar field gravitational lensing (i.e. when considering the appearance of a scalar charge in the lensing scenario), and (c) gravitational lensing in closed universes (with antipodes).The reasons that lead to this degeneracy in the lens equations, the possibility of actually encountering it in the real universe, and eventually the ways to break it, are discussed.Comment: Accepted for publication in Modern Physics Letters

Teaching Work with Foreign Language Text in the Institute of Physical Culture

Рассмотрены вопросы обучения чтению и переводу ино- язычного текста в вузе физической культуры. Приведена классификация видов чтения, свойственная методике обучения иностранному языку. Уделено внимание выполнению упражнений в процессе обучения чтению. Указаны положительные и отрицательные стороны перевода на занятиях по иностранному языку, актуальность выбора средств перевода. Обоснована необходимость обучения студентов грамотному пользованию печатными словарями.The article is devoted to the issues of teaching reading and translation of a foreign language text. The classification of types of reading, which is usual for the methodology of teaching a foreign language, is given. Attention is paid to the implementation of exercises in the process of learning to read. The positive and negative aspects of translation in foreign language classes are described. The relevance of the choice of means of translation is mentioned. The necessity of teaching students the competent use of printed dictionaries is substantiated

Development of Self-Monitoring in the Process of Teaching Foreign Languages to the Students of Physical Culture Universities

Рассматривается вопрос осуществления самоконтроля обучающимися в иноязычном образовательном процессе. Приводится классификация приемов самоконтроля, которые преподаватель может использовать в обучении студентов иностранным языкам. Обосновывается необходимость специальной подготовки обучающихся по организации самоконтроля в условиях реализации компетентностного и личностно-ориентированного подходов. Уделяется внимание использованию интерактивных методов обучения как средству развития самоконтроля.The article deals with the implementation of students’ self-monitoring in foreign educational process. Classification of selfmonitoring methods that the teacher can use in teaching foreign language students is conducted. The need for special preparation of students for the self-monitoring organization in terms of competency and student-centered approaches is justified. Attention is paid to the use of interactive teaching methods as a means of developing self-monitoring

Comment on "Clock Shift in High Field Magnetic Resonance of Atomic Hydrogen"

In this Comment, we reanalyze the experiments on the collision frequency shift of the b-c and a-d hyperfine transitions in three-dimensional atomic hydrogen in the presence of, respectively, a and b-state atoms. Accurate consideration of the symmetry of the spatial and spin part of the diatomic wavefunction yields the difference a_T-a_S=0.30(5) \AA between the triplet and singlet s-wave scattering lengths of hydrogen atoms. This corrects the factor-of two error of the commented work [Phys. Rev. Lett. 101, 263003 (2008)].Comment: 1 pag