Ground-penetrating radar stratigraphy and dynamics of megaflood gravel dunes

Ground-penetrating radar was used to elucidate the stratigraphy of late Pleistocene gravel dunes in the Altai Mountains of southern Siberia that formed when a lake emptied as a result of ice-dam failure. Survey-lines across dunes had a resolution of decimetres, with depth penetration of 20 m. The reflections identify bounding surfaces and radar facies. Two classes of unconformities are identified: (1) an erosional unconformity at the base of the dunes; (2) steeply inclined unconformities that truncate underlying inclined reflections and are downlapped by overlying inclined reflections within the dunes. Unconformities define six radar facies (RF): RF 1, basal subhorizontal discordant reflections; RF 2, poorly defined discordant reflections; RF 3, planar inclined reflections; RF 4, sigmoidal inclined reflections; RF 5, trough fills; RF 6, low-angle inclined reflections. The basal unconformity represents the flood-cut surface, across which the dunes migrated. The inclined unconformities may be interpreted in two ways: (1) erosional surfaces induced by unsteady flow within one flood, or (2) erosional surfaces developed by a series of floods reactivating dunes left stranded by previous floods. The evidence favours the latter model, which is consistent with the occurrence of several dune-forming events within the basin. The broader implications of the study are considered with respect to investigations of megaflood bedforms worldwide

Fibrinogen splice variation and cross-linking: Effects on fibrin structure/function and role of fibrinogen γ’ as thrombomobulin II

Fibrin is an important matrix protein that provides the backbone to the blood clot, promoting tissue repair and wound healing. Its precursor fibrinogen is one of the most heterogenous proteins, with an estimated 1 million different forms due to alterations in glycosylation, oxidation, single nucleotide polymorphisms, splice variation and other variations. Furthermore, ligation by transglutamimase factor XIII (cross-linking) adds to the complexity of the fibrin network. The structure and function of the fibrin network is in part determined by this natural variation in the fibrinogen molecule, with major effects from slice variation and cross-linking. This mini-review will discuss the direct effects of fibrinogen αEC and fibrinogen γ’ splice variation on clot structure and function and also discuss the additional role of fibrinogen γ’ as thrombomodulin II. Furthermore, the effects of cross-linking on clot function will be described. Splice variation and cross-linking are major determinants of the structure and function of fibrin and may therefore impact on diseases affecting bleeding, thrombosis and tissue repair

α−α Cross-Links Increase Fibrin Fiber Elasticity and Stiffness

Fibrin fibers, which are ∼100 nm in diameter, are the major structural component of a blood clot. The mechanical properties of single fibrin fibers determine the behavior of a blood clot and, thus, have a critical influence on heart attacks, strokes, and embolisms. Cross-linking is thought to fortify blood clots; though, the role of α–α cross-links in fibrin fiber assembly and their effect on the mechanical properties of single fibrin fibers are poorly understood. To address this knowledge gap, we used a combined fluorescence and atomic force microscope technique to determine the stiffness (modulus), extensibility, and elasticity of individual, uncross-linked, exclusively α–α cross-linked (γQ398N/Q399N/K406R fibrinogen variant), and completely cross-linked fibrin fibers. Exclusive α–α cross-linking results in 2.5× stiffer and 1.5× more elastic fibers, whereas full cross-linking results in 3.75× stiffer, 1.2× more elastic, but 1.2× less extensible fibers, as compared to uncross-linked fibers. On the basis of these results and data from the literature, we propose a model in which the α-C region plays a significant role in inter- and intralinking of fibrin molecules and protofibrils, endowing fibrin fibers with increased stiffness and elasticity

Effects of plasma heating on the magnitude and distribution of plasma flows in the helical divertor of the Uragan-3M torsatron

Recently, a strong up-down asymmetry in the poloidal distributions of diverted plasma flows has been observed in the l = 3/m = 9 Uragan-3M torsatron, in many features similar to what have been observed in the l = 2 Heliotron E heliotron/torsatron. With this asymmetry, the predominant outflow of the diverted plasma is directed with the ion toroidal drift. On this basis, the asymmetry can be related to the space non-uniformity of the charged particle loss. In the work reported, the magnitude of divertor flow in U-3M and the vertical asymmetry in its distribution are studied as functions of the heating parameter P/, P being the power absorbed in the plasma, and are juxtaposed with corresponding P-related changes in the density and fast ion content in the plasma. As P/ increases, an increase of fast ion content and of particle loss, on the one hand, and an increase of divertor flow magnitude and of vertical asymmetry of the flow, on the other hand, are observed. A mutual accordance between these processes validates the hypothesis on a dominating role of fast particle loss in formation of vertical asymmetry of divertor flows in helical devices

Divertor flow and particle loss behaviors in spontaneous change of confinement state in the URAGAN-3M torsatron

Under conditions of spontaneous change of plasma confinement state having been observed recently in the U-3M torsatron with a natural helical divertor, it is shown that at the initial phase of this change all the components of the diverted plasma flow (DPF) decrease, while thermal (TI) and suprathermal (STI) ion content in the bulk plasma increases and the TI+STI fraction in the DPF is reduced on the ion В×∇В drift side, thus indicating an improvement of ion confinement. The initial phase is ended by a DPF rise on the ion В×∇В drift side, a TI+STI content decay in the bulk plasma and a rise of TI+STI outflow into the DPF, these being indications of an ion confinement deterioration. However, a simultaneous DPF reduction on the electron В×∇В drift side and a rise of electron density and ECE indicate an improvement of electron confinement.В умовах виявленої раніше спонтанної зміни режиму утримання в торсатроні У-3М з природним гвинтовим дивертором показано, що на початковій стадії цієї зміни зменшуються всі складові плазмового диверторного потоку (ПДП), в той час, як зростає кількість теплових (ТІ) та надтеплових (НТІ) іонів в основній плазмі, засвідчуючи про покращення їх утримання. Початкова стадія завершується зростанням ПДП на боці іонного дрейфу В×∇В, зменшенням кількості ТІ та НТІ в основній плазмі та підвищеним виходом їх до ПДП, що є ознакою погіршення утримання іонів. Але одночасне зменшення ПДП на боці електронного дрейфу В×∇В і зростання електронної густини та електронного циклотронного випромінювання вказують на покращення утримання електронів.В условиях обнаруженного ранее спонтанного изменения режима удержания в торсатроне У-3М с естественным винтовым дивертором показано, что на начальной стадии этого изменения уменьшаются все составляющие плазменного диверторного потока (ПДП) и растёт содержание тепловых (ТИ) и сверхтепловых (СТИ) ионов в основной плазме, свидетельствуя об улучшении их удержания. Начальная стадия завершается возрастанием ПДП на стороне ионного дрейфа В×∇В, уменьшением содержания ТИ и СТИ в основной плазме и повышенным их уходом в ПДП, что говорит об ухудшении удержания ионов. Однако, при этом уменьшается ПДП на стороне электронного дрейфа В×∇В и растут плотность электронов и электронное циклотронное излучение, что указывает на улучшение удержания электронов

Formation of ITB in the vicinity of rational surfaces in the Uragan-3M torsatron

It was shown that there is the possibility of ITB formation in the vicinity of rational surfaces in a torsatron magnetic configuration. The formation of ITB is accompanied by fast change of plasma poloidal rotation velocity, radial electric field and its shear and the decrease of plasma density fluctuations. After the ITB formation the transition to the improved plasma confinement takes place. The transition stars when electron temperature in the region of rational surfaces is sufficient to satisfy the condition υTe/uei>>2πR0 (here υTe is electron thermal velocity and uei is the frequency of ion – electron collisions, and R0 is the major radius of the torus). Such a regime can be maintained during the whole duration of RF discharge without any disturbances.Показано, що існує можливість формування внутрішнього теплового бар’єру (ВТБ) в плазмі ВЧ розряду в околиці раціональних поверхонь в торсатронній магнітній конфігурації. Формування ВТБ супроводжується бистрими змінами швидкості полоідального обертання плазми, радіального електричного поля и його шира і зменшенням флуктуацій густини плазми поблизу раціональних поверхонь. Після формування ВТБ спостерігається перехід в режим поліпшеного утримання плазми. Час переходу зменшується із збільшенням ВЧ потужності нагріву.Показано, что имеется возможность формирования внутреннего теплового барьера (ВТБ) в плазме ВЧ разряда в окрестности рациональных поверхностей в торсатронной магнитной конфигурации. Формирование ВТБ сопровождается быстрыми изменениями скорости полоидального вращения плазмы, радиального электрического поля и его шира и уменьшением флуктуаций плотности плазмы вблизи рациональных поверхностей. После формирования ВТБ наблюдается переход в режим улучшенного удержания плазмы. Время перехода сокращается с увеличением ВЧ мощности нагрева

Usage of Neologisms Formed by Derivation in Online Advertising

The article provides a brief overview of the principles of formation and usage of neologisms formed by derivation in English advertising materials. A description of existing methods and characteristics of derivative word formation in English is given, and examples of modern neologisms in advertising are analyzed. The research is focused on the lexical role of neologisms in the context of modern online advertising, their nominative and stylistic functions in the English advertising text.</p

Research and development of the mathematic models of cryptosystems based on the universal Diophantine language

This paper shows the objective necessity of improving the information security systems under the development of information and telecommunication technologies. The paper for the first time involves a new area of NP-complete problems from Diophantine analysis, namely, multi-degree systems of Diophantine equations of a given dimension and degree of Tarry-Escott type. Based on a fundamentally new number-theoretic method, a mathematical model of an alphabetic information security system (ISS) has been developed that generalizes the principle of building cryptosystems with a public key – the so called dissymmetric bigram cryptosystem. This implies to implement direct and inverse transformations according to a given algorithm based on a two-parameter solution of a multi-degree system of Diophantine equations. A formalized algorithm has been developed for the specified model of a dissymmetric bigram cryptosystem and a training example based on a normal multi-degree system of Diophantine equations of the fifth degree is presented