Decomposition dynamics of the wrack of different origin in the black sea sandy littoral

The role of sand interstitial community in process of decomposition of different origin wrack (seaweed, seagrass and mussel) are considered in with the results of laboratory experiments. Quantitative changes of organic matter content, bacteria, marine fungi, microalgae, flagellates, ciliates and insects in wrack and underlying sand are studied. The results obtained in the laboratory closed to the natural condition

Tank Structural Fatigue Fracture in Hydrocarbon Transportation

The article touches upon the reasons of cracks formation in a vertical steel tank wall used in oil transportation. Here are given the comparative research results of chemical composition and mechanical properties of steel, used in manufacture of the flat product: tensile strength, yield strength, impact strength and hardness

Consciousness: effect of coaching process and specifics through AI usage

The main purpose of the article is to investigate how coaching itself affects a person and evaluate it as an effective tool. The second goal is to find out what the features of coaching with the use of an AI-based assistant are. The problem of studying the effectiveness of coaching is indicated by the purpose of finding out, based on the results of the work in the session, to what extent the result obtained will lead the respondent to specific actions. To this end, the main measurable metrics were stress level, willingness to act, and clarity regarding the request. The study confirmed that the majority of sessions had a “positive” dynamic in at least one of the consciousness components (an increase of clarity or willingness to act and decrease of stress). The key implication is that it is important to keep a coachee away from stress to create space for clarity and willingness to act. The research results show that an AI-based tool is more effective in new requests with high importance for a client regarding willingness to act and clarity, confidential requests in terms of privacy, and sensitivity regarding clarity. A coach is perceived as overall stronger in usefulness, effectiveness, and stress reduction. Analyzing the results of the coach-AI-assistant interaction, the study shows that AI broadens the vision of coaches. From the point of view of the threat of the coach-bot interaction, there is a bottleneck that emerged during the feedback process during the study. In several sessions, coaches were not able to develop an emotional connection well enough through written dialogue – due to the absence of face-to-face contact. One of the key outcomes regarding the “client-coach” interaction is the high importance of emotional contact

Exact analytical solutions of a steady-state mushy layer model containing heat exchange with the environment

A set of nonlinear equations describing the crystallization of a binary melt in the presence of a quasi-equilibrium mushy layer is analytically solved in the case of heat exchange with the environment. Solute concentration, temperature distributions, and a bulk fraction of the solid phase in a mushy region are found. In addition, the average interdendritic distance in the two-phase region, which characterizes the structural-phase transition and porosity of the material, was analytically determined. The mushy layer’s thickness was also found as a function of given the physical and operating parameters of the solidification process. The analytical solutions obtained are compared with experimental data

Optimal Nitrogen Supply Ameliorates the Performance of Wheat Seedlings under Osmotic Stress in Genotype-Specific Manner

Strategies and coping mechanisms for stress tolerance under sub-optimal nutrition conditions could provide important guidelines for developing selection criteria in sustainable agriculture. Nitrogen (N) is one of the major nutrients limiting the growth and yield of crop plants, among which wheat is probably the most substantial to human diet worldwide. Physiological status and photosynthetic capacity of two contrasting wheat genotypes (old Slomer and modern semi-dwarf Enola) were evaluated at the seedling stage to assess how N supply affected osmotic stress tolerance and capacity of plants to survive drought periods. It was evident that higher N input in both varieties contributed to better performance under dehydration. The combination of lower N supply and water deprivation (osmotic stress induced by polyethylene glycol treatment) led to greater damage of the photosynthetic efficiency and a higher degree of oxidative stress than the individually applied stresses. The old wheat variety had better N assimilation efficiency, and it was also the one with better performance under N deficiency. However, when both N and water were deficient, the modern variety demonstrated better photosynthetic performance. It was concluded that different strategies for overcoming osmotic stress alone or in combination with low N could be attributed to differences in the genetic background. Better performance of the modern variety conceivably indicated that semi-dwarfing (Rht) alleles might have a beneficial effect in arid regions and N deficiency conditions

Semisynthetic Amides of Amphotericin B and Nystatin A₁: A Comparative Study of In Vitro Activity/Toxicity Ratio in Relation to Selectivity to Ergosterol Membranes

Polyene antifungal amphotericin B (AmB) has been used for over 60 years, and remains a valuable clinical treatment for systemic mycoses, due to its broad antifungal activity and low rate of emerging resistance. There is no consensus on how exactly it kills fungal cells but it is certain that AmB and the closely-related nystatin (Nys) can form pores in membranes and have a higher affinity towards ergosterol than cholesterol. Notably, the high nephro- and hemolytic toxicity of polyenes and their low solubility in water have led to efforts to improve their properties. We present the synthesis of new amphotericin and nystatin amides and a comparative study of the effects of identical modifications of AmB and Nys on the relationship between their structure and properties. Generally, increases in the activity/toxicity ratio were in good agreement with increasing ratios of selective permeabilization of ergosterol- vs. cholesterol-containing membranes. We also show that the introduced modifications had an effect on the sensitivity of mutant yeast strains with alterations in ergosterol biosynthesis to the studied polyenes, suggesting a varying affinity towards intermediate ergosterol precursors. Three new water-soluble nystatin derivatives showed a prominent improvement in safety and were selected as promising candidates for drug development

Decomposition dynamics of the wrack of different origin in the black sea sandy littoral

The role of sand interstitial community in process of decomposition of different origin wrack (seaweed, seagrass and mussel) are considered in with the results of laboratory experiments. Quantitative changes of organic matter content, bacteria, marine fungi, microalgae, flagellates, ciliates and insects in wrack and underlying sand are studied. The results obtained in the laboratory closed to the natural condition

Decomposition Dynamics of the Wrack of Different Origin in the Black Sea Sandy Littoral

The role of sand interstitial community in process of decomposition of different origin wrack (seaweed, seagrass and mussel) are considered in with the results of laboratory experiments. Quantitative changes of organic matter content, bacteria, marine fungi, microalgae, flagellates, ciliates and insects in wrack and underlying sand are studied. The results obtained in the laboratory closed to the natural condition