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  • Author: S. Sokolov x
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Abstract

The third-stage larvae of Daniconema anguillae Moravec et Køie, 1987 are found in the eels fins caught from Dringis Lake (Lithuanian National park). The morphology of these larvae is briefly described.

Summary

The phylogenetic analysis of partial SSU, LSU (rDNA) and COI (mtDNA) sequences was performed for the quimperiid nematode Ichtyobronema hamulatum, a common parasite of the burbot Lota lota. The study of SSU (for 2007 bp long alignment) has shown that in all kinds of analyses I. hamulatum cluster with Paraquimperia africana (Quimperiidae), while another quimperiid, Paraseuratum sp., unites in a separate clade with Spectatus spectatus (Kathlaniidae). Both groups do not form direct phylogenetic links with the rest of seuratoid nematodes (i.e. Cucullanidae and Seuratidae). Obtained data (for 1080 bp long alignment) exhibit the phylogenetic affinity of I. hamulatum and P. africana with kathlaniids of the genus Falcaustra. The analysis of LSU sequences has revealed that I. hamulatum occupies the basal position in relation to all other members of Spirurina and Rhabditina.

Abstract

There are a lot of models and algorithms to minimize risks during dredging operations and they are not without drawbacks. The paper describes the authors’ approach to solving this problem. Mathematical models are proposed and on their basis software is developed. Methods of the risk theory are used to minimize the risks. In this paper a consequence of influence refers to the deviation from the goal expressed in the expected results and the deviation of certain criterion factors. In this case, we mean any measure of quality. In its turn, risk factors reduce criterion factors. These factors are divided into categories - general transportation risks and risks of transporting ground. In these categories, one may derive the following risks - incidents at transport resulting from the impact of a set of random factors including the human one. For risk analysis and management, in addition to identifying critical chains of risk situations, the stochastic model for evaluating the chains is set forth. In order to implement this algorithm, the mathematical package Maple is used, which allows for conducting the required calculations with a software package including the Graph Theory. The paper presents fragments of the code listing.

Summary

The trematode Postlepidapedon opisthobifurcatum () is a common intestinal parasite of the gadiform fishes of the Southern Ocean. In this work, we supplement the description of the species with the anatomy of the terminal part of the reproductive system and with molecular data. The male terminal genitalia are characterised by the presence of the external seminal vesicle and cirrus-sac. The external seminal vesicle is surrounded by aciniform groups of outer prostatic cells. Groups of outer prostatic cells and proximal parts of their ducts are associated with a thin-walled membrane that is connected to the proximal edge of the cirrus-sac. The cirrus-sac is claviform, with a long proximal part accommodating the tubular, thin-walled internal seminal vesicle and ducts of outer prostatic cells. The female terminal genitalia are represented by a thick-walled metraterm, which is surrounded by aciniform groups of glandular cells. Phylogenetic analysis based on 28S rDNA partial sequences data placed P. opisthobifurcatum into the monophyletic group Lepidapedidae, including the species Myzoxenus insolens (Crowcroft, 1945), Intusatrium robustum Durio et Manter, 1968, and Postlepidapedon uberis . However, we were unable to detect direct phylogenetic connections between P. opisthobifurcatum and P. uberis.

Abstract

The objective of this study was to assess the regeneration response of in vitro cultured Magnolia × soulangeana ‘Alexandrina’ and Magnolia liliiflora ‘Nigra’ to nutrient medium composition. In the primary culture (initiated from dormant axillary buds) combinations of Murashige and Skoog (MS) basal salts with 6-benzylaminopurine and α-naphthaleneacetic acid were tested. The primary explants of cv. ‘Alexandrina’ expressed higher regeneration rate than cv. ‘Nigra’. For both species, the regen eration was most strongly potentiated at addition of 0.25 mg dm−3 of the cytokinin alone. The auxin exerted undesir–able effects. Several basal salts media were applied in proliferation stage and their physiological effects were evaluated in reference to traditionally used MS. At culturing on Chée & Pool C2d Vitis Medium (VM) that is for the first time introduced to magnolia and on MS, M. liliiflora formed more but less elongated shoots than M. soulangeana. However, on VM, substantial increase (25-30%) of the number of axillary shoots and leaves, shoot length and fresh and dry weights over MS was established for both species. This suggested VM as promising composition of nutrients in multiplication stage. Microshoots obtained on MS, VM, Rugini Olive Medium and DKW Juglans Medium were successfully rooted in vitro and subsequently established ex vitro. The findings expand the information on magnolia response to culture conditions and contribute to elaboration of innovative elements of protocols for establishing tissue cultures with high regeneration capacity.

Abstract

The gastrointestinal tract perforation is one of the leading causes of acute abdomen. Mycotic infections have become a significant clinical problem over the last few decades. Despite the advance in diagnostics and treatment of patients with fungal peritonitis, the mortality remains high.

Objective. The objective of the study was to determine the type and incidence of causative pathogens of acute peritonitis in patients with gastroduodenal perforation, and to estimate the impact of microbial flora on the disease outcome.

Materials and methods. We performed a retrospective study among 83 adult patients with acute peritonitis due to gastroduodenal perforation treated at our centre.

Results. A total of 40 mycotic agents were isolated in 39 of the abdominal samples. The primary mycotic isolates were Candida albicans (52.5%) and C. glabrata (64.3%); C. krusei (14.3%) and C. tropicalis (7.1%) predominated among non-albicans Candida species (35.0%). The most common bacterial agents were Escherichia coli (24.0%) and Enterococcus spp. (24.0%). 77.1% of all enrolled patients survived, and 19 of them deceased due to sepsis and multiple organ dysfunction syndrome.

Conclusion. Candida albicans is the most common mycotic pathogen in patients with acute peritonitis due to gastroduodenal perforation. It is obligatory to examine the peritoneal fluid samples for bacterial and fungal pathogens with determination of their antimicrobial susceptibility profile. Timely initiation of adequate treatment and multidisciplinary approach is crucial for the outcome of patients with fungal peritonitis.

Abstract

In this study, the effects of compounds providing Fe in chelated (NaFeEDTA and Fe(III)AC) and non-chelated (FeSO4·7H2O) forms as components of culture media, on in vitro shoot multiplication and rooting of Magnolia soulangeana ‘Alexandrina’, Magnolia grandiflora and Prunus cerasifera ‘Nigra’ were comparatively evaluated. Each of the tested chemicals was used as a single Fe source in the basal salt medium. In the stages of shoot multiplication and rooting plant response was scored by biometrical indices (number of shoots, leaves and roots, shoot and root length, percent of rooted plants and root hairs). The occurrence of physiological disorders was estimated by visual observations. In presence of FeSO4, symptoms of chlorosis, hyperhy-dricity, early senescence and specific morphology of roots, suggesting Fe deficiency, were observed. These deteriorations were entirely prevented at the application of Fe chelates of which, in this experimental systems, Fe(III)AC was tested for the first time. The addition of Fe(III)AC positively affected the plant quality to extent comparable to that of NaFeEDTA. The obtained data suggest that both applied Fe chelates are more appropriate than non-chelated Fe form and can be alternatively used in the optimization of nutrient media for micropropagation of Magnolia and Prunus cerasifera genotypes.

Abstract

Substitution of fossil-based chemical processes by the combination of electrochemical reactions driven by sources of renewable energy and parallel use of H2O and CO2 to produce carbon and hydrogen, respectively, can serve as direct synthesis of bulk chemicals and fuels. We plan to design and develop a prototype of electrochemical reactor combining cathodic CO2-reduction to ethylene and anodic H2O oxidation to hydrogen peroxide. We perform ab initio calculations on the atomistic 2D graphene-based models with attached Cu atoms foreseen for dissociation of CO2 and H2O containing complexes, electronic properties of which are described taking into account elemental electrocatalytical reaction steps. The applicability of the model nanostructures for computer simulation on electrical conductivity of charged Cun/graphene (0001) surface is also reported.

Abstract

Broadly educated professionals are a rely valuable resource for the Russian public health system in the current socio-economic conditions. Their capability to flexibly switch the focus and content of their activities in the changing and challenging environment is essential for successful performance.

The purpose of our study is to analyze the international evidence on managing the process of competencies’ development in healthcare managers.

Competence-oriented education and training of future health-care managers is of special interest. In light of this, the study of international data on the organization of the processes of key competence development is important. Here with, it is necessary to take into account the content of the studies, resources and technologies, factors that influence on this process, the development and evaluation of models aimed at improvement of the education of healthcare management professionals at medical schools.

We believe that the results of this review will help to develop and offer a number of practical steps aimed at optimizing the education and training of healthcare managers. In addition to a review of international data, this article presents an innovative project for the development of professional competencies of health managers – the Academy of Talent Development in Healthcare (ATDH). This project involves students of the Sechenov University who want to learn how to lead healthcare teams efficiently.

Summary

The trematode Amurotrema dombrowskajae Achmerow, 1959, is the type and the only species of the paramphistomoid genus Amurotrema Achmerow, 1959. This intestinal parasite of grass carp (Ctenopharyngodon idella) was introduced with host to the Volga River Delta. These naturalized trematodes were found by the authors in 2014 – 2015. In the present study the phylogenetic position of Amurotrema dombrowskajae is analysed using partial 28S rDNA nucleotide sequences. Bayesian inference and Maximum Likelihood analyses place this species in a clade with representatives of the family Cladorchiidae - Megalodiscus temperatus (Stafford, 1905) and Indosolenorchis hirudinaceus Crusz, 1951. Thus, molecular data are consistent with the traditional view on the position of A. dombrowskajae in this family.