774 research outputs found
Siberian crane chick calls reflect their thermal state
Chicks can convey information about their needs with calls. But it is still unknown if there are any universal need indicators in chick vocalizations. Previous studies have shown that in some species vocal activity and/or temporal-frequency variables of calls are related to the chick state, whereas other studies did not confirm it. Here, we tested experimentally whether vocal activity and temporal-frequency variables of calls change with cooling. We studied 10 human-raised Siberian crane (Grus leucogeranus) chicks at 3–15 days of age. We found that the cooled chicks produced calls higher in fundamental frequency and power variables, longer in duration and at a higher calling rate than in the control chicks. However, we did not find significant changes in level of entropy and occurrence of non-linear phenomena in chick calls recorded during the experimental cooling. We suggest that the level of vocal activity is a universal indicator of need for warmth in precocial and semi-precocial birds (e.g. cranes), but not in altricial ones. We also assume that coding of needs via temporal-frequency variables of calls is typical in species whose adults could not confuse their chicks with other chicks. Siberian cranes stay on separate territories during their breeding season, so parents do not need to check individuality of their offspring in the home area. In this case, all call characteristics are available for other purposes and serve to communicate chicks’ vital needs
USE OF SEDIMENT QUALITY GUIDELINES FOR THE ASSESSMENT OF CONTAMINATED SEDIMENTS OF UKRAINIAN ESTUARIES
The article describes that many countries throughout the world share similar concerns about sediment management. Scientists in several countries have developed a variety of methods for evaluating the de-gree to which sediment-associated chemicals might adversely affect aquatic organisms. The results of ex-periment where consensus approach was used for sediments assessment of Dnieper and Buh estuary and Danube estuary in Ukraine are presented in article
Long-term stability in the vocal duets of the endangered Siberian Crane Leucogeranus leucogeranus
Vocal-based monitoring is increasingly being used as a non-invasive method for identifying individuals within avian populations and is promising for the Siberian Crane, Leucogeranus leucogeranus. This is a poorly studied, long-lived, secretive and critically endangered bird species that breeds in the Arctic tundra of western and eastern regions of Siberia. We assessed between- and within-year stability of individual-specific vocal features in duets of Siberian Crane and tested the effect of pair-mate change on their stability. Previous findings showed that duets are specific to different pairs of birds; however, it is still unknown how long pair-specific traits of duets remain and if they change in the course of a year or when birds re-mate. We recorded duets of 15 reproductively active pairs in the Oka Crane Breeding Centre in 2003–2006 and 2013–2017. We found that pair-specific vocal signatures remained stable both within the year and across ~ 10 years. After a change of mate, most of the variables we measured in the call did not change in any of the birds. Our data suggest that the stability of the individually specific vocal features may enable Siberian Cranes to be reliably identified by their duets over the birds’ lifetime. We believe that our work can increase confidence in the use of acoustic recognition techniques for endangered crane monitoring programs. Our results also suggest that Siberian Cranes may use their duets to form long-term social bonds between neighbours
Female Scent Signals Enhances Male Resistance to Influenza
Scent of receptive females as signal to reproduction stimulate male mice to olfactory search of a potential breeding partner^1, 2^. This searching behavior is coupled with infection risk due to bacterial contamination of the fecal and urine scent marks^4^. The theoretical consideration of host evolution under inevitable parasitic pressures, including helminthes, bacteria, virus etc., predicts adaptations that help protect against parasites associated with breeding^7^. In this study, we propose that acceptation of female signals by male mice leads to adaptive redistribution of immune defense directed to protection against respiratory infection risks. Our results reveal migration of macrophages and neutrophils to upper airways upon exposure to female odor stimulus resulting in increased resistance to influenza virus in male mice. Contrary to widely accepted immunosuppressive function of female sexual signals, our data provide the first demonstration of the adaptive immunological response to female odor stimulus through induction of nonspecific immune response in upper airways
Voice breaking and its relation to body mass and testosterone level in the Siberian Crane (Leucogeranus leucogeranus)
Vocal development of cranes (Gruidae) has attracted scientifc interest due to its special stage, voice breaking. During voice breaking, chicks of diferent crane species produce calls with two fundamental frequencies that correspond to those in adult low-frequency and juvenile high-frequency vocalizations. However, triggers that afect voice breaking in cranes are mainly unknown. Here we studied the voice breaking in the Siberian Crane (Leucogeranus leucogeranus) and test its relation to the body mass and testosterone level. We analyzed 5846 calls, 39 body mass measurements and 60 blood samples from 11 Siberian Crane chicks in 8 ages from 2.5 to 18 months of life together with 90 body mass measurements and 61 blood samples from 24 Siberian Crane adults. The individual duration of voice breaking and dates of its onset, culmination and completion depended neither on the body mass nor on the testosterone level at various ages. But we found correlation between the testosterone level and mean deltas of percentages of the high and low frequency components in Siberian Crane calls between the closest recording sessions. We also observed some coincidence in time between the mean dates of voice breaking onset and the termination of body mass gain (at 7.5 months of age), and between the mean dates of voice breaking completion and the start of a new breeding season. Similar relations have been shown previously for some other crane species. We also showed for the frst time that the mean dates of voice breaking culmination correlated with the signifcant increase of the testosterone level (at 10.5 months of age). So, we suggest that voice breaking in cranes may be triggered by the end of chicks’ body growth, is stimulated by the increase of testosterone level and ends soon after adult cranes stop taking care of their chicks
Treatment of acute complicated pancreatic pseudocysts
The results of surgery in 70 patients with acute complicated pancreatic pseudocysts in age from 21 to 79 years were analyzed. For patients using an individualized medical – diagnostic campaign, which primarily was aimed at the elimination of complications following treatment with most of the pseudocyst in the long-term. In most cases, using percutaneous drainage for the purpose of the stabilization patient's general well-being, the possibility of the influence on the development the sepsis and severe organ dysfunction. If found impossible using this minimally invasive methods, and only when it is impossible to use them, or the development of complications after surgery, or results are unsatisfactory, performed "open" surgery. Mortality in complicated acute pseudocysts was 3.4 %
ДОЗВІЛЛЯ АНТИЧНОСТІ В КОНТЕКСТІ ВИДОВИЩНОЇ КУЛЬТУРИ: ГЛАДІАТОРСЬКІ ІГРИ
The article presents the analysis of leisure in the context of spectacular ancient culture gladiatorial games based on ancient literary reflection of the work of historians, philosophers, poets, writers and orators of ancient Greece and Rome. Based on the study, the author found the transformation of leisure as a social and humanitarian experience of ancient society, established the nature and content of the gladiatorial games as a form of mass entertainment antiquity. The author described the moral aspects of gladiatorial games in the context of spectacular culture of antiquity.В статье осуществлен анализ досуга античности в контексте зрелищной культуры гладиаторских игр на основе античной литературной рефлексии, в частности сквозь призму работ историков, философов, поэтов, писателей и ораторов древних Греции и Рима. На основе проведенного исследования автором обнаружены трансформации досуга как социального и гуманитарного опыта античного общества, установлена сущность и содержание гладиаторских игр как массовой формы досуга античности. Автором охарактеризованы моральные аспекты гладиаторских игр в контексте зрелищной культуры античности.У статті здійснено аналіз дозвілля античності у контексті видовищної культури гладіаторських ігор на основі античної літературної рефлексії, зокрема крізь призму праць істориків, філософів, поетів, письменників й ораторів стародавніх Греції і Риму. На ґрунті проведеного дослідження автором виявлено трансформації дозвілля як соціального і гуманітарного досвіду античного суспільства, встановлено сутність та зміст гладіаторських ігор як масової форми дозвілля античності. Автором охарактеризовано моральні аспекти гладіаторських ігор у контексті видовищної культури античності
Mass transfer in aggregated porous media with nonlinear compressibility
The problem of the squeezing out of a solution from aggregates in a porous medium has been considered and investigated. A specific feature of the problem lies in taking account of the existence of two compaction zones in deforming aggregates of a porous medium. Features essential to mass transfer in a deformable aggregated porous medium have been determined and analyzed. © 2008 Springer Science+Business Media, Inc
Mathematical Model of Hydraulic Fracturing of a Bed
© 2016, Springer Science+Business Media New York.A study has been made of the problem on the process of formation of a zone of higher-than-average permeability with a moving boundary in an initially low-permeability porous medium (problem on hydraulic fracturing of a bed) in a three-dimensional formulation. A characteristic feature of the three-dimensional problem was the taking into account the existence of two zones (zone with a regular permeability and the destruction zone) in the porous medium, whose contact region was determined using the condition of mass balance on the moving boundary. Special features fundamental to the process of mass transfer in such filtration-inhomogeneous porous media have been revealed and analyzed
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