Dynamical correlations near dislocation jamming

Dislocation assemblies exhibit a jamming or yielding transition at a critical external shear stress value $\sigma=\sigma_c$. Nevertheless the nature of this transition has not been ascertained. Here we study the heterogeneous and collective nature of dislocation dynamics within a crystal plasticity model close to $\sigma_c$, by considering the first-passage properties of the dislocation dynamics. As the transition is approached in the moving phase, the first passage time distribution exhibits scaling, and a related peak {\it dynamical} susceptibility $\chi_4^*$ diverges as $\chi_4^* \sim (\sigma-\sigma_c)^{-\alpha}$, with $\alpha \approx 1.1$. We relate this scaling to an avalanche description of the dynamics. While the static structural correlations are found to be independent of the external stress, we identify a diverging dynamical correlation length $\xi_y$ in the direction perpendicular to the dislocation glide motion.Comment: 4 pages, 5 figure

Distributional Impacts of CAP Adoption on Romanian Households

This paper focuses on estimation of distributional economic welfare effects of the adoption of the CAP on different groups of Romanian households. The calculations of welfare effects are based on 1999 household data and refer to a 10-fold breakdown of Romanian households, i.e. five socio-economic categories from urban and rural areas, taking into account own (home) production of food. To identify the most vulnerable groups of Romanian consumers to food price changes, the Slutsky approximation Compensating Variation approach is applied. The results suggest that, if the current CAP is adopted and results in food price changes averaging a 10 per cent increase in all food prices, the lowest-income groups (i.e. urban and rural unemployed households, urban pensioner households) will be the most affected, ceteris paribus (prices of all other goods held constant). The minimum amount by which the groups could be compensated for the effect of price change on their real incomes varies between Euro 3 per month for employers' households (about 1% of total income) and about Euro 8 per month for farmers' households (6%). However, due to the relatively large shares of food self-production in total consumption, in particular by rural households, somewhat smaller money compensation would be appropriate.distributional economic effects, CAP, Slutsky approximation, Compensating Variation, Romania, Agricultural and Food Policy,

Determination of combustion gas temperatures by infrared radiometry in sooting and nonsooting flames

Flame temperatures in nonsooting and sooting environments were successfully measured by radiometry for pre-mixed propane-oxygen laminar flames stabilized on a water-cooled, porous sintered-bronze burner. The measured temperatures in the nonsooting flames were compared with fine-wire thermocouple measurements. The results show excellent agreement below 1700 K, and when the thermocouple measurements were corrected for radiation effects, the agreement was good for even higher temperatures. The benefits of radiometry are: (1) the flow is not disturbed by an intruding probe, (2) calibration is easily done using a blackbody source, and (3) measurements can be made even with soot present. The theory involved in the radiometry measurements and the energy balance calculations used to correct the thermocouple temperature measurements are discussed

Entanglement in fermionic systems

The anticommuting properties of fermionic operators, together with the presence of parity conservation, affect the concept of entanglement in a composite fermionic system. Hence different points of view can give rise to different reasonable definitions of separable and entangled states. Here we analyze these possibilities and the relationship between the different classes of separable states. We illustrate the differences by providing a complete characterization of all the sets defined for systems of two fermionic modes. The results are applied to Gibbs states of infinite chains of fermions whose interaction corresponds to a XY-Hamiltonian with transverse magnetic field.Comment: 13 pages, 3 figures, 4 table

Stress-induced nuclear accumulation is dispensable for Hog1-dependent gene expression and virulence in a fungal pathogen

The authors thank E. Veal for intellectual input. This work was funded by the UK Biotechnology and Biological Research Council [J.Q. BB/K016393/1; A.J.P.B. BB/K017365/1], the National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) [D.M.M. NC/N002482/1] and the Wellcome Trust Strategic Award in Medical Mycology and Fungal Immunology [097377]). D.M.M. and A.J.P.B. are also supported by the MRC Centre for Medical Mycology at the University of Aberdeen (MR/N006364/1).Peer reviewedPublisher PD