Dynamic Postural Stability and Hearing Preservation after Cochlear Implantation

OBJECTIVES (1) To assess dynamic postural stability before and after cochlear implantation using a functional gait assessment (FGA). (2) To evaluate the correlation between loss of residual hearing and changes in dynamic postural stability after cochlear implantation. METHODS Candidates for first-sided cochlear implantation were prospectively included. The FGAs and pure-tone audiograms were performed before and 4-6 weeks after cochlear implantation. RESULTS Twenty-three subjects were included. Forty-eight percent (n = 11) showed FGA performance below the age-referenced norm before surgery. One subject had a clinically relevant decrease of the FGA score after cochlear implantation. No significant difference between the mean pre- and postoperative FGA scores was detectable (p = 0.4). Postoperative hearing loss showed no correlation with a change in FGA score after surgery (r = 0.3, p = 0.3, n = 16). CONCLUSION Single-sided cochlear implantation does not adversely affect dynamic postural stability 5 weeks after surgery. Loss of functional residual hearing is not correlated with a decrease in dynamic postural stability

Simulation of Scattering Process in Radiation Techniques Exploiting the Theory of Markovian Processes with Random Structure

There are a lot of physical and technical problems that need to calculate photon density distribution functions for the photon flow passing materials of different type. This flow can be described by a type of transport equations similar to the Boltzmann equation. Notwithstanding the huge number of equation types depending upon the particularities of the photon-matter interactions, the main properties of their trajectories are similar. Therefore it is possible to find a generalized model description for the photon trajectories which can be used to solve a large number of other problems.</p

Simple and Complex Substrates (Sugar, Acetate and Milk Whey) for In Situ Bioremediation of Groundwater with Nitrate and Actinide Contamination

The complex contamination of groundwater near radioactive waste repositories by nitrates and actinides is a common problem for many nuclear fuel cycle facilities. One of the effective methods to remove nitrates and reduce actinide migration activity is bioremediation through the activation of native microbial communities by soluble electron donors and carbon sources. This work evaluated the effectiveness of using simple and complex electron donors to remove nitrate in the microbial community in an aquifer near the B2 storage of the Siberian Chemical Combine (Seversk, Siberia). The addition of sugar and milk whey led to the maximum efficiency of nitrate-ion removal and a decrease in the redox potential of the system, creating optimal conditions for the immobilization of actinide. Special attention was paid to the behavior of uranium, plutonium, neptunium, and americium under conditions simulating groundwater when sugar, acetate, and milk whey were added and when microbial metabolic products were formed. Neither microbial metabolites nor organic solutions were found to have a significant effect on the leaching of neptunium. At the same time, for plutonium, a decrease in yield was observed when rocks were treated with organic solutions were compared to groundwater treatment without them. Plutonium leaching is significantly affected by rock composition. In rocks with a low clay fraction content, its yield can reach 40%. At the same time, microbial metabolites can increase americium (Am) desorption from rocks with a low clay fraction content. Additionally, particle size analysis was performed using a step-by-step filtration approach, aiming to evaluate the risks that are associated with colloidal phase formation. It was shown that microbiological stimulation resulted in particle enlargement, substantially diminishing the presence of actinides in the form of dissolved or sub-50 nm nanoparticles. This outcome significantly reduced the potential for colloidal and pseudocolloidal transfer, thereby lowering associated risks

Cryptophyte and Photosynthetic Picoeukaryote Abundances in the Bransfield Strait during Austral Summer

A remarkable shift in the species composition and size distribution of the phytoplankton community have been observed in coastal waters along the Antarctic Peninsula over the last three decades. Smaller photoautotrophs such as cryptophytes are becoming more abundant and important for the regional ecosystems. In this study, flow cytometry was used to quantify the smallest phytoplankton in the central Bransfield Strait and explore their distribution across the strait in relation to physical and chemical properties of the two major water masses: the warmer and less saline Transitional Zonal Water with Bellingshausen Sea influence (TBW), and the cold and salty Transitional Zonal Water with Weddell Sea influence (TWW). Pico- and nano-phytoplankton clusters were distinguished and enumerated in the cytograms: photosynthetic picoeukaryotes, cryptophytes (about 9 µm in size), and smaller (3 µm) nanophytoplankton. It was shown that nanophytoplankton developed higher abundances and biomasses in the warmer and less saline TBW. This biotope was characterized by a more diverse community with a pronounced dominance of Cryptophyta in terms of biomass. The results support the hypothesis that increasing melt-water input can potentially support spatial and temporal extent of cryptophytes. The replacement of large diatoms with small cryptophytes leads to a significant shift in trophic processes in favor of the consumers such as salps, which able to graze on smaller prey