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As in many transition countries, also in Georgia rural urban migration as well as migration from the agricultural sector takes place. This also applies to the Kazbegi district, a mountainous region in the Greater Caucasus of Georgia. The main activity in the district is subsistence farming, while only a few agricultural producers are commercially active. As the region offers beautiful nature, during the last decade tourism has been on the rise, while a dwindling interest in the agricultural sector can be observed. However, the growth in tourism also provides opportunities for small-scale agricultural producers to increase their income by marketing their surplus production to the local tourism sector and thereby improving their livelihoods. In turn, an increase in local agri-food products offered might have a positive effect on the tourism sector. Thus, establishing linkages of agricultural food production and rural tourism might contribute to the economic development of the district and even counteract migration to the capital and from the agricultural sector. Through a qualitative study, we aim at identifying local agri-food products suitable for being marketed to the tourism sector and efficient marketing options. In order to do so, we analyze local agri-food chains. Exploratory interviews, focus group discussions and expert interviews provide data for a qualitative content analysis. First results show that food products which require little technological equipment for processing and do not underlie strict food safety standards, like for example honey, seem to be adequate to tap marketing potentials with regard to rural tourism.

During the propagation of an optically smoothed laser beam through a warm plasma the speckle field pattern and the corresponding speckle intensity distribution are modified in time and along the laser propagation direction. It is shown here that the laser–plasma interaction can change the character of speckle statistics from an initially exponential-type limit law to a Weibull-type law. The Weibull distribution is characterized by a power-law-type behavior in a limited interval of the random variable, which is, in the present case, the speckle intensity. The properties of the speckle distributions are studied using methods of extremal and order statistics. The scattering instability process (here stimulated Brillouin forward scattering) causing the change in speckle statistics has an onset behavior associated with a “critical gain” value, as pointed out in work by Rose and DuBois (1993b). The saturation of the instability process as a function of intensity explains the limited interval of the Weibull-type speckle distribution. The differences in the type of the speckle statistics are analyzed by using “excess over threshold” methods relying on the generalized Pareto distribution, which clearly brings to evidence the transition from an exponential type distribution to the Weibull-type distribution as a function of the instability gain value, that is, from the regime below critical gain to values above the critical gain.

A new diagnostic method of the thermal transport zone of a laser‐created plasma at short wavelength (0.26 μm) is presented. This method uses soft x‐ray spectroscopy and allows one to deduce the temperature of the propagating thermal front during the laser interaction. Time‐resolved X–UV spectra of the rear side of thin plastic foils coated on their front side with a thin layer of gold of different thicknesses (50–300 A) are presented. The layers of gold must be sufficiently thin in order to avoid the fact that their spectrum perturbs the heating of the foil by radiative effects. The plastic thicknesses are chosen less or equal to the ablation thickness of the material for the laser illumination conditions, i.e., about 6 μm. The spectrum emitted by the gold layer plays the role of a backlighter that probes the plastic heated by the laser. Computer simulations including radiation (multi) confirm the weak effect of radiation heating particularly for the thinner layers of gold.

We have studied plasma-induced smoothing due to stimulated Brillouin scattering (SBS) under the aspect of the extremal statistics of smoothed laser beams. As pointed out in the work by Rose and DuBois (1994 Phys. Rev. Lett. 72 2883), scattered light can be subject to uncontrolled (or even ‘explosive’) behaviour, associated with a critical gain value for SBS. In this work we show how this critical behaviour can be predicted on the basis of the order statistics of laser speckle fields, and we analyse the transition to uncontrolled behaviour of the laser beam due to the dominance of high intensity speckles.