Perturbational relativistic theory of electron spin resonance g-tensor

We carry out a complete treatment of the leading-order relativistic one-electron contributions, arising from the Breit-Pauli Hamiltonian, to the g-tensor of electron spin resonance spectroscopy. We classify the different terms and discuss their interpretation as well as give numerical ab initio estimates for the F2(-), Cl2(-), Br2(-), and I2(-) series, using analytical response theory calculations with a multiconfigurational self-consistent field reference state. The results are compared to available experimental data. (c) 2004 American Institute of Physics     

Intracerebroventricular antisense knockdown of Gα<Subscript>i2</Subscript> results in ciliary stasis and ventricular dilatation in the rat

Background  

In the CNS, the heterotrimeric G protein Gα_i2 is a minor Gα subunit with restricted localization in the ventricular regions including the ependymal cilia. The localization of Gα_i2 is conserved in cilia of different tissues, suggesting a particular role in ciliary function. Although studies with Gα_i2-knockout mice have provided information on the role of this Gα subunit in peripheral tissues, its role in the CNS is largely unknown. We used intracerebroventricular (icv) antisense administration to clarify the physiological role of Gα_i2 in the ventricular system.     

Some Remarks on Unsharp Quantum Measurements,Quantum Non-Demolition,and All That

The theory of unsharp quantum measurements is reviewed as a generalization of the von Neumann-Lüders measurement theory and applied to measurements of continuous quantities. A generalized notion of repeatability is proposed which is applicable even to intrinsically unsharp continuous observables. As an illustration a precise formulation of a quantum non-demolition (QND) measurement performed on a harmonic oscillator is given.     

Parallel finite element splitting-up method for parabolic problems

An efficient method for solving parabolic systems is presented. The proposed method is based on the splitting-up principle in which the problem is reduced to a series of independent 1D problems. This enables it to be used with parallel processors. We can solve multidimensional problems by applying only the 1D method and consequently avoid the difficulties in constructing a finite element space for multidimensional problems. The method is suitable for general domains as well as rectangular domains. Every 1D subproblem is solved by applying cubic B-splines. Several numerical examples are presented.     

On the deuteron magnetic resonance in single crystals of ND4Cl and ND4Br

The deuteron quadrupole coupling constants in ND₄Cl and ND₄Br have been measured. The results are 179.9±2.0 and 180.0±2.0 kHz, respectively. From the temperature dependence of the line width in ND₄Cl for the d. c. magnetic field along [100] the hindered rotation potential barrier of the ND₄ ⁺-ion was found to be 5.1 kcal/mole. In crystals containing moisture a narrow line component was observed, which is probably due to the formation of an eutectic solution.     

Pathwise Connectivity of a Conformal Boundary

This paper demonstrates that, in dimensions n 3, the metricboundary of a conformal deformation of the unit ball is pathwiseconnected, and even of bounded turning, provided that the conformalscaling factor satisfies a Harnack inequality and the volumegrowth of the deformed space is at most euclidean. 2000 MathematicsSubject Classification 30C65.     

Cesium and barium as honorary d elements: CsN7Ba as an example

Quantum chemical calculations suggest that inverse sandwich compounds with the general formula MN₇ M , where M is an alkali metal (K,Rb,Cs), N₇ is a ten--electron ring, and M is an alkaline-earth metal (Ca,Sr,Ba), are local C _7v minima. Among these systems, the CsN₇Ba molecule is the stablest of all and presents a barrier of 35 kcal/mol to dissociation towards CsNBa and three N₂ molecules. Substantial 5d character is found in the bonding. Possible ways of making these high-energy compounds are discussed. AcknowledgementsThis contribution was written in honor of B.O. Roos. The authors thank him for a long and lasting friendship and for inspiring so deeply the scientific career of L. G. This work was partially supported by Ministero dellUniversitáe della Ricerca Scientifica and The Academy of Finland.Contribution to the Björn Honorary Issue     

The rate of convergence in Orey's theorem for Harris recurrent Markov chains with applications to renewal theory

We derive sufficient conditions for ∝ λ (dx)6Pⁿ(x, ·) - π6 to be of order o(ψ(n)^-1), where Pⁿ (x, A) are the transition probabilities of an aperiodic Harris recurrent Markov chain, π is the invariant probability measure, λ an initial distribution and ψ belongs to a suitable class of non-decreasing sequences. The basic condition involved is the ergodicity of order ψ, which in a countable state space is equivalent to $\text{Σ ψ(n)}\text{P}{}_{\mathrm{i}}\text{{τ}{}_{\mathrm{i}}\text{?n} <∞}$ for some i, where τ_i is the hitting time of the tate i. We also show that for a general Markov chain to be ergodic of order ψ it suffices that a corresponding condition is satisfied by a small set.We apply these results to non-singular renewal measures on $\text{R}$ providing a probabilisite method to estimate the right tail of the renewal measure when the increment distribution F satisfies ∝ tF(dt) 0; > 0 and ∝ ψ(t)(1- F(t))dt< ∞.     

The measurement statistics interpretation of quantum mechanics: Possible values and possible measurement results of physical quantities

Starting with the Born interpretation of quantum mechanics, we show that the quantum theory of measurement, supplemented by the strong law of large numbers, leads to a measurement statistics interpretation of quantum mechanics. A probabilistic characterization of the spectrum of a physical quantity is given, and an analysis of the notions of possible values and possible measurement results is carried out.