On subalgebras of the first Weyl skewfield

In this note two subalgebras of the skew field of fractions of the first Weyl algebra are described. One is isomorphic to the group ring of a free group with two generators. Another is maximal in the class of subalgebras with finite Gelfand-Kirillov dimension.     

Analysis of the degradation products of chemical warfare agents using a portable capillary electrophoresis instrument with various sample injection devices

In the present research, the performance of three sample injection devices in a portable capillary electrophoresis (CE) instrument was examined. These were the so-called cross-sampler, horizontal injection channel and vertical injection channel. All the three showed a good reproducibility of migration times (the relative standard deviation (RSD) was 4.3% in the case of the cross-sampler, 6.0% in the case of the horizontal injection channel and 1.7% in the case of the vertical channel). However, the reproducibility of peak areas was not sufficient. Hence, this study was mainly focused on qualitative analysis. The cross-sampler injection device was used in the portable CE instrument to analyse the composition of degradation products of chemical warfare agents (CWA). For the analysis of CWA degradation products simple procedures for the extraction of phosphonic acids from different surfaces, such as soil, concrete and granite blocks, tile floor, were developed.     

Microwaves and cellular immunity. I. Effect of whole body microwave irradiation on tumor necrosis factor production in mouse cells

Whole body microwave sinusoidal irradiation of male NMRI mice with 8.15-18 GHz (1 Hz within) at a power density of 1 microW/cm2 caused a significant enhancement of TNF production in peritoneal macrophages and splenic T lymphocytes. Microwave radiation affected T cells, facilitating their capacity to proliferate in response to mitogenic stimulation. The exposure duration necessary for the stimulation of cellular immunity ranged from 5 h to 3 days. Chronic irradiation of mice for 7 days produced the decreasing of TNF production in peritoneal macrophages. The exposure of mice for 24 h increased the TNF production and immune proliferative response, and these stimulatory effects persisted over 3 days after the termination of exposure. Microwave treatment increased the endogenously produced TNF more effectively than did lipopolysaccharide, one of the most potential stimuli of synthesis of this cytokine. The role of microwaves as a factor interfering with the process of cell immunity is discussed.     

Hydromagnetic elasto-viscous fluid flow between two parallel walls: Temperature field. — II

Summary A formula for the temperature field is obtained for elasto-viscous flow between two parallel walls, one is fixed and the other moves periodically in time. The effects of the elastic parameter on temperature and heat transfers at the walls are obtained.     

Students’ emergent articulations of uncertainty while making informal statistical inferences

Research on informal statistical inference has so far paid little attention to the development of students?? expressions of uncertainty in reasoning from samples. This paper studies students?? articulations of uncertainty when engaged in informal inferential reasoning. Using data from a design experiment in Israeli Grade 5 (aged 10?C11) inquiry-based classrooms, we focus on two groups of students working with TinkerPlots on investigations with growing sample size. From our analysis, it appears that this design, especially prediction tasks, helped in promoting the students?? probabilistic language. Initially, the students oscillated between certainty-only (deterministic) and uncertainty-only (relativistic) statements. As they engaged further in their inquiries, they came to talk in more sophisticated ways with increasing awareness of what is at stake, using what can be seen as buds of probabilistic language. Attending to students?? emerging articulations of uncertainty in making judgments about patterns and trends in data may provide an opportunity to develop more sophisticated understandings of statistical inference.     

Hydromagnetic elastico-viscous fluid flow between two parallel walls: Velocity field.-I

Summary The effect of the elastic properties of the fluid on the MHD Couette flow of a conducting viscous fluid between two parallel walls is studied when one wall is fixed and the other is moving periodically in time. Exact solution for the velocity field in the boundary layer is obtained. Also expressions for the shear stress at different layers and the skin-friction at the two walls have been obtained.     

Size effect study in magnetoelectric BiFeO3 system

In this paper, we report for the first time finite size effects on Néel temperature (T _N) of magnetoelectric BiFeO₃ system. Novel wet chemical route has been developed to produce fine particles of BiFeO₃ with controlled size and size distribution. Unlike other oxide systems, lattice volume contraction has been observed with decrease in particle size. The decrease in T _N is co-related to unit cell volume contraction occurring with reduction in particle size.     

On orbits of fractional linear transformations

Let K be a field and let σ(t) be an automorphism of k(t) of infinite order. In his paper [1] Gerard Cauchon asked whether the transformation which is naturally defined on kU∞ by σ has infinitely many infinite orbits. This is indeed so.