Bragg solitons in nonlinear PT-symmetric periodic potentials

It is shown that slow Bragg soliton solutions are possible in nonlinear complex parity-time (PT) symmetric periodic structures. Analysis indicates that the PT-symmetric component of the periodic optical refractive index can modify the grating band structure and hence the effective coupling between the forward and backward waves. Starting from a classical modified massive Thirring model, solitary wave solutions are obtained in closed form. The basic properties of these slow solitary waves and their dependence on their respective PT-symmetric gain/loss profile are then explored via numerical simulations.Comment: 6 pages, 4 figures, published in Physical Review

Classical Particle in Presence of Magnetic Field, Hyperbolic Lobachevsky and Spherical Riemann Models

Motion of a classical particle in 3-dimensional Lobachevsky and Riemann spaces is studied in the presence of an external magnetic field which is analogous to a constant uniform magnetic field in Euclidean space. In both cases three integrals of motions are constructed and equations of motion are solved exactly in the special cylindrical coordinates on the base of the method of separation of variables. In Lobachevsky space there exist trajectories of two types, finite and infinite in radial variable, in Riemann space all motions are finite and periodical. The invariance of the uniform magnetic field in tensor description and gauge invariance of corresponding 4-potential description is demonstrated explicitly. The role of the symmetry is clarified in classification of all possible solutions, based on the geometric symmetry group, SO(3,1) and SO(4) respectively

Expression, Purification, and Biophysical Characterization of a Secreted Anthrax Decoy Fusion Protein in Nicotiana benthamiana.

Anthrax toxin receptor-mediated drug development for blocking anthrax toxin action has received much attention in recent decades. In this study, we produced a secreted anthrax decoy fusion protein comprised of a portion of the human capillary morphogenesis gene-2 (CMG2) protein fused via a linker to the fragment crystallizable (Fc) domain of human immunoglobulin G1 in Nicotiana benthamiana plants using a transient expression system. Using the Cauliflower Mosaic Virus (CaMV) 35S promoter and co-expression with the p19 gene silencing suppressor, we were able to achieve a high level of recombinant CMG2-Fc-Apo (rCMG2-Fc-Apo) protein accumulation. Production kinetics were observed up to eight days post-infiltration, and maximum production of 826 mg/kg fresh leaf weight was observed on day six. Protein A affinity chromatography purification of the rCMG2-Fc-Apo protein from whole leaf extract and apoplast wash fluid showed the homodimeric form under non-reducing gel electrophoresis and mass spectrometry analysis confirmed the molecular integrity of the secreted protein. The N-glycosylation pattern of purified rCMG2-Fc-Apo protein was analysed; the major portion of N-glycans consists of complex type structures in both protein samples. The most abundant (>50%) N-glycan structure was GlcNAc₂(Xyl)Man₃(Fuc)GlcNAc₂ in rCMG2-Fc-Apo recovered from whole leaf extract and apoplast wash fluid. High mannose N-glycan structures were not detected in the apoplast wash fluid preparation, which confirmed the protein secretion. Altogether, these findings demonstrate that high-level production of rCMG2-Fc-Apo can be achieved by transient production in Nicotiana benthamiana plants with apoplast targeting

Interacting nonlinear wave envelopes and rogue wave formation in deep water

A rogue wave formation mechanism is proposed within the framework of a coupled nonlinear Schrodinger (CNLS) system corresponding to the interaction of two waves propagating in oblique directions in deep water. A rogue condition is introduced that links the angle of interaction with the group velocities of these waves: different angles of interaction can result in a major enhancement of rogue events in both numbers and amplitude. For a range of interacting directions it is found that the CNLS system exhibits significantly more extreme wave amplitude events than its scalar counterpart. Furthermore, the rogue events of the coupled system are found to be well approximated by hyperbolic secant functions; they are vectorial soliton-type solutions of the CNLS system, typically not considered to be integrable. Overall, our results indicate that crossing states provide an important mechanism for the generation of rogue water wave events

The application of acoustic curtains during the renovations works

W referacie przedstawiono wyniki badań doświadczalnych kotar akustycznych. Badane kotary zastosowane były na ogrodzenia placu, gdzie prowadzono prace remontowe. Źródłem dźwięku (hałasu) były małe maszyny robocze do prac ziemnych. Wyniki badań doświadczalnych porównano z wynikami podobnych badań z zastosowaniem przenośnych ekranów akustycznych obniżających hałas powstały podczas pracy tych samych maszyn. W badaniach wykorzystano program Noise Explorer – Type 7815. Analiza otrzymanych wyników pozwoliła na sformułowanie wniosków o praktycznym zastosowaniu.This paper presents the results of experimental studies of acoustic curtains. The tested curtains were used on the fence of square where the renovations works were carried out. The small working machines for earthworks were the source of sound (noise). The results of experimental studies were compared with the results of similar studies with the application of mobile acoustic screens during the work of the same machines. The program Noise Explorer – Type 7815 was used during researches. The analysis of obtained results allowed to formulate the conclusions which have a practical application

El Triàsic de Castellar del Vallès : geologia i icnologia

General structural and stratigraphic characteristics from the studied zone (Can Sallent, Castellar del Vallès), are coincident with the ones described by other authors. Geomorphologic and historic variation of the outcrops have been important to determinate the geology of Can Sallent, because of human activity. Ichnites have been found in Middle Muschelkalk bottom levels, and have been analyzed using photogrametry techniques. Two different ichnotaxons have been found. Rhynchosauroides isp. Stratigraphic correlation with other sections with Rhynchosauroides isp. activity indicates the ichnotaxon was present along Middle Muschelkalk, specially at the bottom.Las características estructurales y estratigráficas generales de la zona estudiada (Can Sallent, Castellar del Vallés), coinciden con las realizadas hasta ahora por otros autores. Las variaciones históricas de los afloramientos y la geomorfología han sido importantes para deducir la geología de Can Sallent debido a la actividad humana. Situadas en la parte basal del Muschelkalk medio, se encuentra unas icnitas que, mediante la técnica de fotogrametría, han sido analizadas. Estas icnitas corresponden a dos tipos de icnotaxones. Las más abundantes son Rhynchosauroides isp. La correlación estratigráfica con otras secciones donde hay presencia de este taxón en la Sierra Prelitoral Catalana indica que el icnotaxton está presente a lo largo del Muschelkalk medio, pero predomina especialmente en la base de este.Les característiques estructurals i estratigràfiques generals de la zona estudiada (Can Sallent, Castellar del Vallès), coincideixen amb les realitzades fins ara per altres autors. Les variacions històriques dels afloraments i la geomorfologia han estat importants per deduir la geologia de Can Sallent degut a una activitat humana. Situades a la part basal del Muschelkalk mitjà, és troben unes icnites que, mitjançant la tècnica de fotogrametria, han estat analitzades. Aquestes icnites corresponen a dos tipus d'icnotaxons. Les més abundants són Rhynchosauroides isp. La correlació estratigràfica amb altres seccions on hi ha presència d'aquest taxó a la Serralada Prelitoral Catalana indica que l'icnotaxó es present al llarg de tot el Muschelkalk mitjà, però es especialment predominant a la base d'aquest