69 research outputs found

    Ecological optimum of ectothermic organisms: static-dynamical approach

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    During 20th century the majority of researchers interpreted ecological optimum as a certain combination of ambient factors which is optimal for growth, existence and reproduction of an organism. However, it was revealed in many species, that the maximum rates of various processes in an organism are achieved at various combinations of values of different factors, and under variable regimes as opposite to constant regimes. One may state that there is no well defined general concept which takes into account a bulk of data that do not conform the traditional definition of ecological optimum. Here, we show that it is necessary to make distinction between concepts of "static" and "dynamic" optima. It is needed for definition of real ecological optimum and creation of optimum conditions for given factor. We show also that it is necessary to take into account so-called delayed effects of factors. Basing on the analysis of responses of zooplankton to various temperatures and phosphoric load, we show that an optimum has "dynamic" characteristics besides previously known "static" ones, like a range of factor values on tolerance curve or a doze of factor. These "dynamic" characteristics are cyclic and stepwise changes of a factor, a directionality of factor's dynamics in case of stepwise changes and additionally, we reveal stimulating and inhibiting delayed effects of factors. Our results allow for a more detailed concept of ecological optimum, and also may stimulate investigations of quantitative contribution of various parameters of environmental factors to an ecological optimum of an organism or population

    Motor activity of Daphnia magna (Crustacea, Cladocera) during thermal selection: Peculiarities of search reactions in the non-uniform environment

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    We conducted a study of the peculiarities of the motor activity of juvenile and adult individuals of Daphnia magna in the process of thermal selection. On the example of Daphnia, we experimentally proved the assumption that the decrease in the motor activity of the ectotherms in the selected temperature range is a behaviour mechanism typical for thermal selection. The experiment was conducted on the offspring of one parthenogenetic female (pure line) of a laboratory culture maintained over several years at room temperature. The Daphnia individuals had been beforehand acclimated over several generations to 23.4 ºС, and then were placed in a thermogradient apparatus. The control individuals were maintained at room temperature. The final temperature preference was determined using the so-called "chronic" method, when the tested organisms are maintained in a thermogradient apparatus over several days. The positions of the Daphnia individuals were recorded daily during 24 days. As a parameter which would characterize the motor activity of Daphnia, we used the parameter of average relative shifting, which was calculated as a difference (in cm) between the position they were found in two sequential records, divided by time (in min) between these records. Over the first 3 days, in the conditions of the temperature gradient, the Daphnia mostly selected heightened temperatures (24–28 ºС). During the period from the 4th to 24th day, 74% of the Daphnia selected the range of 18–23 ºС and 85% – 17–24 ºС. Thus, the range of the ultimate selected temperatures decreased by 4 ºС compared to the initially selected temperatures and enlarged by 3 ºС towards the lower temperatures. In the thermogradient apparatus, the parthenogenetic females had the lowest value of the mean relative movement. In the control, at room temperature, this parameter of the adults was by 43% higher compared to the gradient. The pattern of the dynamic of the indicator in both variants of the experiment was similar for the periods and phases of fluctuations. With the juveniles the value of the parameter of mean relative shifting in the gradient was higher by 40% compared to the adult Daphnia, but close to the parameter of the adults in the control. We determined a relationship between the juveniles selecting the higher temperatures and higher mean relative shifting, which indicates a relationship between the behavioural selective reaction of juvenile Daphnia and general physiological condition of their organism. During the absence of the temperature gradient, the Daphnia were observed to show symmetry in their motor reaction. Occurrence of the asymmetry of the motor reaction of the Daphnia in the condition of the thermogradient, manifesting in the prevalence of shifting to lower or higher temperatures, can indicate more clearly manifested search reaction in the condition of a non-uniform environment

    The Specifics of Training Workers of Industrial Enterprises in Modern Conditions

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    В статье рассмотрены особенности, возможности и значение подготовки рабочих-сварщиков промышленных предприятий с ориентацией подготовки на специфику этих предприятий.The article discusses the features, opportunities and importance of training welders of industrial enterprises with the orientation of training on the specifics of these enterprises

    Factors associated with adverse outcome among hospitalized patients with moderate to severe COVID-19

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    Aims. To consider factors associated with adverse outcome among hospitalized patients with moderate and severe COVID-19.Materials and methods. Data from 345 case histories of adult patients hospitalized with moderate to severe COVID-19 were analyzed in a single-center retrospective study. Characteristics by sex, age, number of days from disease onset to admission to hospital, duration of hospitalization, duration of disease, population characteristics by medical history of comorbidities and self-medication, outcome of hospitalization and medical technologies used in hospital conditions were given for the whole cohort of patients. All parameters were analyzed using descriptive statistics methods. Qualitative variables are given in absolute (n) and relative (%) values with 95% confidence interval. Continuous variables were presented as median and quartiles. Risk factors for mortality were determined across groups using the χ2  criterion and odds ratio.Results. There was no demonstrated effect of gender, degree of pulmonary tissue lesions on computed tomography data, or time of initiation of respiratory support on disease outcome. At the same time, the age older than 65 years as well as neoplasms, type 2 diabetes mellitus, dementia, Stage 3 arterial hypertension, chronic heart failure, coronary heart disease, myocardial infarction and stroke history, chronic obstructive pulmonary disease, bronchiectatic disease, urogenital diseases were the predictors of unfavorable outcome in patients with moderate and severe COVID-19 form. Prehospital use of antiplatelet agents, direct and indirect oral anticoagulants, drugs affecting the renin-angiotensin system, systemic glucocorticosteroids, antibiotics, antiviral drugs, and analgesics was associated with a decrease in the mortality rate in patients with moderate-to-severe COVID-19, as well as timely use of pronposition and transfer to intensive care unit.Conclusions. Our findings are partially consistent with previous reports on the effect of risk factors on COVID-19 outcomes

    『新撰万葉集』の風物表現に関する和漢比較研究——上巻の和歌と漢詩を中心に

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    《新撰万叶集》成立于“国风暗黑时代”向“和风复兴时代”转变的过程中,在日本古典文学史上占有极其重要的地位。该集由上下两卷组成,其中上卷的每一首和歌的左边都附有一首七言绝句,可以说包含着编撰者特殊的编撰意图。该集这种“和汉共存”的特点不断吸引着和汉比较文学学界的关注。 至今为止的研究主要是从“和汉共存”出发,围绕该集的和歌和汉诗的表达、抑或是和歌和汉诗的关系论而展开的。为了更加客观地把握该集在日本古典文学史上的地位,我们要对“和汉共存”这一点开展进一步的研究。本论文把该集的汉诗作者看成该集和歌的鉴赏者之一。并由此出发,摒弃一直以来对本集的汉诗所持的偏见,把《新撰万叶集》上卷的和歌和其相应的汉诗...「国風暗黒時代」から「和風復興時代」へと進行していった過程に成立された『新撰万葉集』(以下は「本集」とも)は、日本古典文学史上で極めて重要な地位を占めている。本集は上下二巻からなるが、上巻は和歌とともにその左に七言絶句が付されているもので、特別な編纂意図が含まれるに違いない。その「和漢共存」という点で和漢比較文学学界の注目を引き続く。 今日まで、「和漢共存」から主に本集における和漢詩歌の表現や和歌と漢詩との関係論をめぐって行われてきたが、本集の日本古典文学史における地位をより客観的に把握するために、更なる研究が期待される。本論は、本集の漢詩作者は本集の和歌の鑑賞者でもあることから出発し、従来の本集の漢詩に対する偏見に挑み、『新撰万葉集』上巻の和歌とそれに付される漢詩を、平安人の作詩を中心とする文学上の訓練とその成果の総決算の縮図の一つと見なす。その認識の上で、先学の研究成果を踏まえながら...学位:文学硕士院系专业:外文学院日本语言文学系_日语语言文学学号:1222007115181

    КОРРЕКЦИЯ ГЛУТАМИНОМ МОРФОФУНКЦИОНАЛЬНЫХ НАРУШЕНИЙ ТОНКОЙ КИШКИ И ПЕЧЕНИ В ПОСТТРАВМАТИЧЕСКОМ ПЕРИОДЕ УШИБА СЕРДЦА (экспериментальное исследование)

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    Objective: to evaluate the effect of glutamine on functional and morphological changes in the liver and small bowel in the posttraumatic period of cardiac contusion.Material and methods. An experimental model of isolated cardiac contusion was used to investigate the activity of amylase from all small intestinal segments and that of alanine aminotransferase (ALAT), γ-glutamyl transferase (γ-GT), and cholinesterase (CE) in the rat serum over time during the posttraumatic period without correction, as well as during the enteral use of glutamine. Light microscopy (hematoxylin and eosin staining) was employed to evaluate the effect of glutamine on morphological changes in the small bowel (proximal, middle, and distal segments) and liver of experimental animals in the posttraumatic period of cardiac contusion.Results. The injured animals receiving glutamine versus those without correction showed a decrease in the activity of some desorbed γ-amylase fractions, ALAT, and γ-GT and an increase in the activity of CE in different posttraumatic periods of cardiac contusion. The small intestinal morphological pattern was characterized by the absence of signs of stasis, marginal neutrophil standing, and undamaged intramural nerve ganglia. The liver specimens from the animals receiving glutamine exhibited reduced necrotic area sizes and the absence of protein precipitates in the vessels and fatty dystrophy.Conclusion. Small intestinal and liver functional and morphological improvements due to the use of glutamine in experimental cardiac contusion suggest that the amino acid is involved in the metabolism of hepatocytes and enterocytes and give grounds to consider it to be a protector of extrathoracic organs in blunt cardiac injury. Цель исследования — оценка влияния глутамина на функциональные и морфологические изменения печени и тонкой кишки в посттравматическом периоде ушиба сердца.Материал и методы. На модели изолированного экспериментального ушиба сердца исследовали активность амилазы всех отделов тонкой кишки, активность аланинаминотрансферазы (АлАТ), γ-глютамилтрансферазы (ГГТ) и холинэстеразы (ХЭ) в сыворотке крови крыс в динамике посттравматического  периода  без  коррекции,  а  также  в  условиях  энтерального  применения  глутамина;  методом  световой микроскопии (окраска гематоксилином и эозином) провели оценку влияния глутамина на морфологические изменения тонкой кишки (проксимального, среднего и дистального отделов) и печени экспериментальных животных в посттравматическом периоде ушиба сердца.Результаты. В группах травмированных животных, получавших глутамин, отмечено снижение (по сравнению с травмированными животными без коррекции) активности некоторых десорбируемых фракций γ-амилазы, снижение активности АлАТ, ГГТ, повышение активности ХЭ в различные сроки посттравматического периода ушиба сердца. Морфологическая картина тонкой кишки отличалась отсутствием признаков стаза  и  краевого  стояния  нейтрофилов,  отсутствием  повреждения  интрамуральных  нервных  ганглиев.  В  препаратах печени животных, получавших глутамин, отмечалось уменьшение в размерах зон некроза, отсутствие белковых преципитатов в сосудах, жировой дистрофии.Заключение. Улучшение функционального и морфологического состояния тонкой кишки и печени в условиях применения глутамина при экспериментальном ушибе сердца свидетельствует о включении аминокислоты в метаболизм гепатоцитов и энтероцитов, а также дает основания рассматривать его в качестве протектора экстраторакальных органов в условиях тупой травмы сердца.

    Project Method as a Way of the Formation of Student’ Professional and Language Competencies of Non-Linguistic High School

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    В статье раскрывается потенциал дисциплины «Иностранный язык» для формирования профессиональных и языковых компетенций студентов бакалавриата направления «Биология» Балтийского федерального университета имени И. Канта посредством применения проектного метода. Статья содержит описание проведенного совместного проекта Ресурсным центром иностранных языков и Ботаническим садом.The article reveals the potential of the discipline «Foreign language» to form professional and language competencies of Bachelor students with Biology major at I. Kant Baltic Federal university applying the project method. The article contains the description of the project organized by Resource centre of foreign languages and Botanical Garden

    RD39 Status Report 2009

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    RD39 Status Report 2009. CERN RD39 Collaboration is developing super-radiation hard cryogenic silicon detectors for applications of LHC experiments and their future upgrades. The activities of RD39 Collaboration were focused in 2009 on concept of charge injected detector (CID)

    Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR

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    Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (mu_B > 500 MeV), effects of chiral symmetry, and the equation-of-state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2022, in the context of the worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal
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