399 research outputs found

    Behavior of copper chalcogenides during vacuum-thermal processing

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    In this work, thermodynamic functions of evaporation of copper chalcogenides (Cu2S, Cu2Se, and Cu2Te) are determined via previously published data and thermodynamic values obtained by the authors of the work. The obtained results indicate a very low probability of separation of compounds into copper and chalcogen by dissociation under vacuum-thermal processing conditions. Liquid-vapor phase transitions in binary systems Cu2S – Cu2Se, Cu2S – Cu2Te, and Cu2Se – Cu2Te at low pressures of 15 and 0,7 kPa are constructed based on the vapor pressure of copper chalcogenides. It is shown that the pressure eases over the liquid bath impairs the separation of chalcogens, therefore separation in one stage by thermo-vacuum treatment at a pressure of 0,7 – 15 kPa is not possible

    Behavior of copper chalcogenides during vacuum-thermal processing

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    In this work, thermodynamic functions of evaporation of copper chalcogenides (Cu2S, Cu2Se, and Cu2Te) are determined via previously published data and thermodynamic values obtained by the authors of the work. The obtained results indicate a very low probability of separation of compounds into copper and chalcogen by dissociation under vacuum-thermal processing conditions. Liquid-vapor phase transitions in binary systems Cu2S – Cu2Se, Cu2S – Cu2Te, and Cu2Se – Cu2Te at low pressures of 15 and 0,7 kPa are constructed based on the vapor pressure of copper chalcogenides. It is shown that the pressure eases over the liquid bath impairs the separation of chalcogens, therefore separation in one stage by thermo-vacuum treatment at a pressure of 0,7 – 15 kPa is not possible

    Charged-Surface Instability Development in Liquid Helium; Exact Solutions

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    The nonlinear dynamics of charged-surface instability development was investigated for liquid helium far above the critical point. It is found that, if the surface charge completely screens the field above the surface, the equations of three-dimensional (3D) potential motion of a fluid are reduced to the well-known equations describing the 3D Laplacian growth process. The integrability of these equations in 2D geometry allows the analytic description of the free-surface evolution up to the formation of cuspidal singularities at the surface.Comment: latex, 5 pages, no figure

    Eye Hydrodynamics after Combined Treatment of Primary Open-Angle Glaucoma and Complicated Cataract

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    Aim: To study hydrodynamics of the eye after combined treatment – a combination of laser activation of trabecula and cataract phacoemulsification – in a comparative aspect.Material and methods. The study included 65 patients (65 eyes) with initial and advanced stages (I–II stages) of primary open-angle glaucoma (POAG) and complicated cataract. Among the patients there were 38 women (58.5 %) and 27 men (41.5 %), the average age was 68.8 ± 8.2 years. The follow-up period is 12 months after the treatment. The patients were divided into two groups: the main one – 33 patients (33 eyes) who underwent combined treatment – YAG-laser activation of trabecula (YAG-LAT) and phacoemulsification of cataract with intraocular lens (IOL) implantation, the control group – 32 patients (32 eyes) who underwent only phacoemulsification.Initially, the average intraocular pressure (IOP) (P0) in the main and control groups was 20.72 ± 3.39 mm Hg and 21.02 ± 3.55 mm Hg respectively. The average number of antihypertensive drugs used in the study group was 1.53 ± 0.64, in the control group – 1.34 ± 0.55.Results. There were no intraand postoperative complications. By the end of the follow-up period, a significant decrease in the average IOP level compared to its preoperative value by 29.2 % was determined in the main group, and 9.8 % in the control. The average number of antihypertensive drugs used in the study group decreased from 1.53 ± 0.64 to 0.67 ± 0.59 (p < 0.05), in the control group of patients, on the contrary, the average number of antihypertensive agents increased from 1.34 ± 0.55 to 1.91 ± 0.70 (p < 0.05).Conclusion. In the long-term postoperative period after combined treatment (YAG-LAT + phaco), IOP normalization was achieved in 96.9 % of cases, as well as a significant increase in visual acuity of patients. The developed method of treatment is safe, has a minimal risk of complications and can be used for the treatment of patients with initial stages of POAG in combination with complicated cataracts with increased IOP level, inefficiency of antihypertensive therapy

    WRAPPING AROUND THE RECONSTRUCTION PLATE WITH A PECTORALIS MUSCLE FLAP IN MANDIBULAR REPAIR AFTER SEGMENTAL RESECTION

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    The paper gives information on the proposed procedure for wrapping around the reconstruction plate with a pectoralis muscle flap in case of segmental resection of the lower jaw and recovery of its continuity with a titanium plate if there is a sufficient area of integuments (skin and mucosa) and soft tissue shortage

    A CASE OF SURGICAL TREATMENT FOR A PARATRACHEOSTOMIC RECURRENCE OF LARYNGEAL CANCER

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    The paper presents information on a case of successful repair with a pectoral musculocutaneous flap for a paratracheostomic recurrence of laryngeal cancer

    Use of Sorghum for Enhancing the Biodiversity and Nutritional Value of Semi-Desert Pasture Ecosystems

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    The article presents the results of studies on the adaptive potential of sorghum used for restoration of degraded pasture ecosystems, increasing their biodiversity and nutritional value. The region chosen for the experiment is a semi-desert arid part of southern Russia. The aridity coefficient is 0.11–0.30 which is typical of the arid zone. The annual volume of precipitation is 125-265 mm. Two varieties of sorghum – Travinka and Caravan – were studied. They were grown with different thickness: 10 thousand, 20 thousand and 40 thousand plants per 1 hectare. During the growing season, there was soil and atmospheric drought. The best indicators of green mass yield were recorded for Travinka for the variant “40 thousand plants per hectare – 7.9 tons per hectare, and for Caravan for the variant “20 thousand plants per hecrate – 3.9 tons per hectare. Compared with natural pasture, sorghum productivity is 18 times higher by green mass yield and 26 times higher by dry mass yield (the best options). The analysis of the chemical composition and nutritional value of sorghum showed that compared to the plants of natural pasture, sorghum is a more nutritious fodder plant. Its nutritional value is more by 0.24 feed units per 1 kg and by 1.9 % by the mass of crude protein. It is better than other plants by the content of sugar content (79 g per 1 kg) and macronutrients

    Effects of experimental domestication of silver foxes (Vulpes vulpes) on vocal behaviour

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    This paper systematizes and generalizes a research cycle devoted to studying the acoustics and vocal behaviour of silver foxes that differ in their tolerance to humans. The research revealed that 50-year selection for tameness toward people resulted in selective use by Tame foxes toward humans of two call types, pant and cackle. At the same time, the selected for aggression toward people Aggressive foxes and the non-selected for behaviour Control foxes, selectively use toward humans cough and snort. Thus, call types representing vocal indicators of friendly and aggressive behaviour of foxes toward humans have been revealed by the research. Nevertheless, experimental domestication did not change vocal behaviour of foxes toward conspecifics; all three strains did not differ by their vocal behaviour toward same-strain silver foxes. Relationship has been investigated between vocal behaviour and degree of tolerance toward people for hybrids between Tame and Aggressive foxes and for backcrosses to Tame and Aggressive foxes. Effect was estimated between fox sex and the degree of human impact on focal fox for variables of fox vocal behaviour. The research revealed the universal for mammals vocal indicators of emotional arousal that are independent of the emotional valence. Characteristics of vocal behaviour that are related with positive and negative emotional valence have been revealed. A simple and effective method for estimating animal discomfort based on ”joint calls” that takes into account the characteristics of all calls irrespective of their acoustic structure has been revealed. The obtained results provide a basis for further comparative studies of the acoustic structure and vocal behaviour for other taxa of the genus Vulpes and the related canid genera (Canis, Cuon, Lycaon)

    Vocal group signatures in the goitred gazelle Gazella subgutturosa

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    Abstract The potential for vocal modification in mammals has recently been of great interest. This study focuses on the potential for vocal matching in juvenile and adolescent goitred gazelles Gazella subgutturosa that were group housed as part of an animal management programme. Two groups of animals (16 and 19 unrelated individuals, respectively) were recorded at two different ages, juvenile and adolescent, regarding 20-25 calls per individual per age; each group was evaluated in a separate year. Vocal similarity of group members compared to nonmembers was prominent in both ages, but higher in juveniles. Individual identity was prominent in both ages and higher in adolescents. The more prominent vocal indicators of group membership in juveniles could be related to their higher social dependence compared to adolescents. The more individualized calls of adolescents could be a mechanistic consequence of more stable growth at older age. Our results suggest vocal plasticity of goitred gazelles under social influences. These data add to recent evidence about domestic goat kids Capra hircus, suggesting that vocalizations of species that are not capable of imitation are more flexible than previously thought

    Kind granddaughters of angry grandmothers: The effect of domestication on vocalization in cross-bred silver foxes

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    a b s t r a c t The genetic basis of the effects of domestication has previously been examined in relation to morphological, physiological and behavioural traits, but not for vocalizations. According t
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