Asymptotic conservation laws in field theory

A new, general, field theoretic approach to the derivation of asymptotic conservation laws is presented. In this approach asymptotic conservation laws are constructed directly from the field equations according to a universal prescription which does not rely upon the existence of Noether identities or any Lagrangian or Hamiltonian formalisms. The resulting general expressions of the conservation laws enjoy important invariance properties and synthesize all known asymptotic conservation laws, such as the ADM energy in general relativity.Comment: 13 pages, AMS-TeX, amsppt.sty, revised to give a better exposition (we hope), and to correct some typesetting error

Cohomologies of the Poisson superalgebra

Cohomology spaces of the Poisson superalgebra realized on smooth Grassmann-valued functions with compact support on $R^{2n}$ ($C^{2n}) are investigated under suitable continuity restrictions on cochains. The first and second cohomology spaces in the trivial representation and the zeroth and first cohomology spaces in the adjoint representation of the Poisson superalgebra are found for the case of a constant nondegenerate Poisson superbracket for arbitrary n>0. The third cohomology space in the trivial representation and the second cohomology space in the adjoint representation of this superalgebra are found for arbitrary n>1.Comment: Comments: 40 pages, the text to appear in Theor. Math. Phys. supplemented by computation of the 3-rd trivial cohomolog

Morita base change in Hopf-cyclic (co)homology

In this paper, we establish the invariance of cyclic (co)homology of left Hopf algebroids under the change of Morita equivalent base algebras. The classical result on Morita invariance for cyclic homology of associative algebras appears as a special example of this theory. In our main application we consider the Morita equivalence between the algebra of complex-valued smooth functions on the classical 2-torus and the coordinate algebra of the noncommutative 2-torus with rational parameter. We then construct a Morita base change left Hopf algebroid over this noncommutative 2-torus and show that its cyclic (co)homology can be computed by means of the homology of the Lie algebroid of vector fields on the classical 2-torus.Comment: Final version to appear in Lett. Math. Phy

Modeling a Two-Stage High-Power Anode Layer Thruster and its Plume

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76625/1/AIAA-22185-240.pd

Equivalence of conservation laws and equivalence of potential systems

We study conservation laws and potential symmetries of (systems of) differential equations applying equivalence relations generated by point transformations between the equations. A Fokker-Planck equation and the Burgers equation are considered as examples. Using reducibility of them to the one-dimensional linear heat equation, we construct complete hierarchies of local and potential conservation laws for them and describe, in some sense, all their potential symmetries. Known results on the subject are interpreted in the proposed framework. This paper is an extended comment on the paper of J.-q. Mei and H.-q. Zhang [Internat. J. Theoret. Phys., 2006, in press].Comment: 10 page

Analysis of chromosome aberrations by FISH and Giemsa assays in lymphocytes of cancer patients undergoing whole-body irradiation: comparison of in vivo and in vitro irradiation

Abstract. Studies of the frequencies of chromosome exchange aberrations in peripheral lymphocytes provide useful Purpose : To study the cytogenetic eVects of fractionated radiobiodosimetric information (IAEA 1986, Darroudi therapy in peripheral blood lymphocytes of ve cancer patients. 2000). For individual dose estimation, a calibration In vitro experiments were performed in parallel using the same dose-response curve constructed for human lympho- patients undergoing protracted whole-body irradiGiemsa-stained preparations were used to score unstable ation at low doses before local radiotherapy at high aberrations following in vivo and in vitro exposure. dose. Results: A linear dose-response curve was determined for both dicentrics and translocations. The in vivo frequency of translocations was higher than for dicentrics. Dose-response curves Materials and methods generated for translocations following in vivo and in vitro irradiation yielded similar frequencies. In contrast, for dicentrics, in 2.1. Subjects vitro irradiation yielded a higher frequency when compared with data generated following in vivo exposure. The study was performed on ve patients aged Conclusions : For dose reconstruction purposes, translocations fre-23-70 years, one woman and four men, with quency seems to be a more adequate end-point than the scoring advanced cancers and distant metastases

Предоперационная кинетика простатспецифического антигена как ф актор прогноза безрецидивной выживаемости после радикальной прост атэктомии

Objectivе. The purpose of the study – to estimate the prognostic value of preoperative prostate-specific antigen (PSA) doubling time (PSADT) in patients with prostate cancer (PCa) after radical prostatectomy (RP).Materials and Methods. The preoperative PSADT was determined in 92 patients with PCa who underwent RP in FSBI RRCRST. Incidence of biochemical recurrence and adverse pathologic features after surgery (positive lymph nodes and surgical margins, locally advanced and poorly differentiated tumors) were estimate according to the level of preoperative PSADT.Results. The correlation between the preoperative PSA kinetics and postoperative pathological findings after radical prostatectomy was shown. Positive lymph nodes (p = 0.04), locally advanced (p = 0.03) and poorly differentiated tumors (p = 0.046) were significantly more frequent in patients with a PSADT ≤ 20,0 months. The role of preoperative PSADT as a predict of relapse-free survival after radical prostatectomy was confirmed. By multivariate analysis preoperative PSADT ≤ 20 months showed a statistically significant increase in the relative risk of biochemical recurrence.Цель исследования – оценка прогностического значения предоперационного времени удвоения простатспецифического антигена (ВУПСА) у больных раком предстательной железы (РПЖ), перенесших радикальную простатэктомию (РПЭ).Материалы и методы. Предоперационное ВУПСА определено у 92 больных РПЖ, перенесших РПЭ в ФГБУ РНЦРХТ. Оценивалась частота выявления биохимического рецидива (БХР) и неблагоприятных гистологических находок после оперативного лечения (поражение лимфатических узлов, положительный хирургический край, местно-распространенные и низкодифференцированные опухоли) в зависимости от предоперационного ВУПСА.Результаты. Выявлена корреляция между исходной кинетикой ПСА и послеоперационными патологическими находками после РПЭ. У больных с ВУПСА ≤ 20,0 мес достоверно чаще выявлялись опухолевое поражение удаленных регионарных лимфатических узлов (р = 0,04), местное распространение (р = 0,03) и низкодифференцированные опухоли (р = 0,046). Подтверждена роль предоперационного ВУПСА в качестве фактора прогноза безрецидивной выживаемости после РПЭ. По результатам многофакторного анализа предоперационное ВУПСА ≤ 20 мес показало статистически значимое повышение относительных рисков развития БХР

Twisted convolution and Moyal star product of generalized functions

We consider nuclear function spaces on which the Weyl-Heisenberg group acts continuously and study the basic properties of the twisted convolution product of the functions with the dual space elements. The final theorem characterizes the corresponding algebra of convolution multipliers and shows that it contains all sufficiently rapidly decreasing functionals in the dual space. Consequently, we obtain a general description of the Moyal multiplier algebra of the Fourier-transformed space. The results extend the Weyl symbol calculus beyond the traditional framework of tempered distributions.Comment: LaTeX, 16 pages, no figure

Analytical solution of second Stokes problem of behaviour of rarefied gas with Cercignani boundary accomodation conditions

Analytical solution of second Stokes problem of behaviour of rarefied gas with Cercignani boundary accomodation conditions The second Stokes problem about behaviour of rarefied gas filling half-space is analytically solved. A plane, limiting half-space, makes harmonious fluctuations in the plane. The kinetic BGK-equation (Bhatnagar, Gross, Krook) is used. The boundary accomodation conditions of Cercignani of reflexion gaseous molecules from a wall are considered. Distribution function of the gaseous molecules is constructed. The velocity of gas in half-space is found, also its value direct at a wall is found. The force resistance operating from gas on border is found. Besides, the capacity of dissipation of the energy falling to unit of area of the fluctuating plate limiting gas is obtained.Comment: 26 pages, 5 figure