State versus private sector provision of water services in Armenia

Despite increasing advocacy and adaptation of public-private model of water governance worldwide since the 1990s, today only 5% of the world??s population is served by water utilities with private involvement. The present article examines the experience of the water sector in Armenia with private sector participation. The study describes the process of the introduction of public-private partnerships in the water sector and focuses on analyzing the impact of privatization on water utility performance. The analysis employs the partial indicator method for evaluating the impacts in relation to operational, finance, and environmental performance, done by drawing on the database for the five water companies in Armenia. The empirical evidence shows that private participation in general led to improved overall performance. In particular, private involvement resulted in increased operational efficiency in terms of labor productivity, water metering, continuity of service, and revenue collection efficiency. There were mixed improvements in the operating cost coverage ratio. As for environmental performance, there were gains in the reduction of residential water consumption, accompanied, however, by an increase in nonrevenue water.     

The metabolic pathway of 4?Hz mechanical vibration-induced effect on snail heart muscle contractility

It was shown that the 4 Hz 30 dB mechanical vibration (MV) of physiological solution (PS) had modulation effect on snail heart contractility. However, the nature of metabolic pathway of MV-treated PS-induced effect is not clear yet. It was suggested that the MV-induced modulation of water molecules dissociation leads to the variation of reactive oxygen species’ level in cell bathing medium, which could serve as a messenger for switching on the metabolic pathway(s) responsible for modulation of muscle contractility. The aim of present work was to check this hypothesis and to elucidate the metabolic pathway through which the effect of MV-treated PS on heart contractility was realized. For this purpose, the effect of MV on heat fusion periods (HFP) and H₂O₂ content in PS, as well as on heart contractility, ⁴⁵Ca²⁺ efflux, intracellular levels of cGMP and cAMP, muscle hydration, and ouabain binding were studied. It was shown that MV treatment of PS increased the HFP-(21.33 ± 4%) and decreased the H₂O₂ content-(5 ± 0.9%). The intracardiac perfusion by MV-treated PS increased the amplitudes of heart contractility, which was accompanied by the increasing of ⁴⁵Ca²⁺ efflux (252.4 ± 16%), elevation of cGMP’s level (42.05 ± 7%), decreasing of cAMP’s level (82.67 ± 7%), increasing of the tissue hydration (18.64 ± 3%), and increasing of the number of ouabain binding sides (25 ± 4%). It was suggested that MV-induced increasing of heart muscle contraction amplitudes is due to the decreases of H₂O₂ content in the medium, which leads to the elevation of heart muscle contractility in result of activation of cGMP-dependent Na⁺/Ca²⁺ exchange in forward regime.     

The EMF-induced changes in aqua medium’s properties depend on background ionizing radiation, illumination and temperature

The effects of extremely low-frequency electromagnetic field (ELF EMF) and ELF-modulated millimeter waves (MMW) on physicochemical properties of physiological solution (PS) at different environmental medium were studied. The existence of frequency “windows” at 4 Hz and 8 Hz frequencies of ELF EMF and ELF-modulated MMW which have different effects on heat fusion period (HFP), hydrogen peroxide (H₂O₂) formation and oxygen (O₂) content of water solution and different dependency on temperature, background radiation (BGR) and illumination was shown. The obtained data allow us to suggest that cell bathing medium serving as a target through which the biological effects of ELF EMF and ELF-modulated MMW on cells are realized is extra sensitive to environmental factors. Therefore, the variability of experimental data on EMF biological effects, obtained in different laboratories can be explained by different environmental conditions of experiments, which very often are not considered adequately.