Ukrainophile Activism and Imperial Governance in Russia's Southwestern Borderlands

Explores the relationship between the Ukrainian nation-building process and the tsarist state

Direct evidence of nuclear spin waves in Nd2_2CuO4_4 by high-resolution neutron-spin-echo spectroscopy

We investigated the dispersion of nuclear spin waves in Nd$_2$CuO$_4$ by using neutron spin-echo spectroscopy at millikelvin temperatures. Our results show unambiguously the existence of dispersion of nuclear spin waves in Nd$_2$CuO$_4$ at T = 30 mK. A fit of the dispersion data with the spin wave dispersion formula gave the Suhl-Nakamura interaction range to be of the order of 10 {\AA}

A transitional analysis of the welfare cost of inflation

This paper applies new computational methods for studying nonstationary dynamics to reevaluate the welfare cost of inflation. A dynamic stochastic general equilibrium model with heterogeneous agents is studied. Incomplete markets induce agents to hold a fiat currency as insurance against idiosyncratic income fluctuations. Rather than comparing steady state equilibria, I measure the welfare cost of inflation by explicitly modeling the transitional dynamics that arise following a change in monetary policy. Transitional dynamics are shown to increase the welfare cost of inflation substantially. Also, contrary to conventional wisdom, transitional dynamic effects are shown to increase the benefits of reducing the inflation rate.Econometric models ; Inflation (Finance) ; Monetary policy ; Money ; Welfare

Age-dependent differences in human brain activity using a face- and location-matching task: An fMRI study

Purpose: To evaluate the differences of cortical activation patterns in young and elderly healthy subjects for object and spatial visual processing using a face- and location-matching task. Materials and Methods: We performed a face- and a location-matching task in 15 young (mean age: 28 +/- 9 years) and 19 elderly (mean age: 71 +/- 6 years) subjects. Each experiment consisted of 7 blocks alternating between activation and control condition. For face matching, the subjects had to indicate whether two displayed faces were identical or different. For location matching, the subjects had to press a button whenever two objects had an identical position. For control condition, we used a perception task with abstract images. Functional imaging was performed on a 1.5-tesla scanner using an EPI sequence. Results: In the face-matching task, the young subjects showed bilateral (right 1 left) activation in the occipito-temporal pathway (occipital gyrus, inferior and middle temporal gyrus). Predominantly right hemispheric activations were found in the fusiform gyrus, the right dorsolateral prefrontal cortex (inferior and middle frontal gyrus) and the superior parietal gyrus. In the elderly subjects, the activated areas in the right fronto-lateral cortex increased. An additional activated area could be found in the medial frontal gyrus (right > left). In the location-matching task, young subjects presented increased bilateral (right > left) activation in the superior parietal lobe and precuneus compared with face matching. The activations in the occipito-temporal pathway, in the right fronto-lateral cortex and the fusiform gyrus were similar to the activations found in the face-matching task. In the elderly subjects, we detected similar activation patterns compared to the young subjects with additional activations in the medial frontal gyrus. Conclusion: Activation patterns for object-based and spatial visual processing were established in the young and elderly healthy subjects. Differences between the elderly and young subjects could be evaluated, especially by using a face-matching task. Copyright (c) 2007 S. Karger AG, Basel

Fault-Tolerant Operation of an Open-End Winding Five-Phase PMSM Drive with Short-Circuit Inverter Fault

Multi-phase machines are well-known for their fault tolerant capability. Star-connected multiphase machines have fault tolerance in open-circuit. For inverter switch short-circuit fault, it is possible to keep a smooth torque of Permanent Magnet Synchronous Machine (PMSM) if the currents of faulty phases are determined and their values are acceptable. This paper investigates fault-tolerant operations of an open-end fivephase drive, i.e. a multi-phase machine fed with a dual-inverter supply. Inverter switch short-circuit fault is considered and handled with a simple solution. Original theoretical developments are presented. Simulation and experimental results validate the proposed strategy

Electrical isolation of GaN by MeV ion irradiation

The evolution of sheet resistance of n-type GaN epilayers exposed to irradiation with MeV H, Li, C, and O ions is studied in situ. Results show that the threshold dose necessary for complete isolation linearly depends on the original free electron concentration and reciprocally depends on the number of atomic displacements produced by ion irradiation. Furthermore, such isolation is stable to rapid thermal annealing at temperatures up to 900 °C. In addition to providing a better understanding of the physical mechanisms responsible for electrical isolation, these results can be used for choosing implant conditions necessary for an effective electrical isolation of GaN-based devices.This work was partly supported by Conselho Nacional de Pesquisas (CNPq, Brazil) under Contract No. 200541/ 99-4

The controlled indirect coupling between spatially-separated qubits in antiferromagnet-based NMR quantum registers

It is considered the indirect inter-qubit coupling in 1D chain of atoms with nuclear spins 1/2, which plays role of qubits in the quantum register. This chain of the atoms is placed by regular way in easy-axis 3D antiferromagnetic thin plate substrate, which is cleaned from the other nuclear spin containing isotopes. It is shown that the range of indirect inter-spin coupling may run to a great number of lattice constants both near critical point of quantum phase transition in antiferromagnet of spin-flop type (control parameter is external magnetic field) and/or near homogeneous antiferromagnetic resonance (control parameter is microwave frequency).Comment: Latex 5 pages, 1 figure. Presented at International Symposium "Quantum Informatics 2004" Moscow, October 5-8, 2004. Will be published in Proc. SPI