scholarly journals Experimental studies of benthos resistance to mechanical burying under the dredging material

2020 ◽  
Vol 164 ◽  
pp. 01001
Author(s):  
Alexander Chusov ◽  
Mikhail Shilin ◽  
George Gogoberidze ◽  
Julia Lednova ◽  
Nikolai Bobylev
Keyword(s):  
Experimental Studies ◽  
Gulf Of Finland ◽  
Tubifex Tubifex ◽  
Dredged Material ◽  
Stress Effect ◽  
Benthic Organisms ◽  
Melanoides Tuberculata ◽  
Marine Sand ◽  
Series Of Experiments ◽  
Neva Bay

The goal of the fulfilled research is the study of the influence of the sedimentary suspension from the dredging material on the benthic hydrobionts. In laboratory aquariums six series of experiments were carried out with triple replication on the ability of different benthic organisms to dig out the soil strata due to their periodic burying by marine sand. These experiments were oriented on biota of Eastern Gulf of Finland and the Neva Bay, where a number of deposit sites for dredging material are located presently. Representatives of three main groups of hydrobionts of these areas were selected for experiments – Chironomidae, Gastropoda and Oligochaeta. The ability of different hydrobiont species to overcome the stress effect of the burying under the dredged material was estimated quantitatively. The results show, that the resistance of the studied species to mechanical burying is decreasing in accordance to the scheme: Chironomus plumosus > Melanoides tuberculata > Tubifex tubifex, and depends from the thickness of the layer of dredged material.

scholarly journals Long-term monitoring of the dredged material deposit sites in the Eastern Gulf of Finland

2020 ◽  
Vol 164 ◽  
pp. 01010
Author(s):  
Alexander Chusov ◽  
Mikhail Shilin ◽  
George Gogoberidze ◽  
Nikolai Bobylev ◽  
Alexandra Ershova ◽  
...  
Keyword(s):  
Zero Point ◽  
Condition Index ◽  
Gulf Of Finland ◽  
Dredged Material ◽  
Monitoring Methods ◽  
Biological Communities ◽  
Environmental Status ◽  
Term Monitoring ◽  
Neva Bay

The goal of the paper is summarizing the results of the 20-years monitoring of the deposit sites of the dredged material in the Eastern Gulf of Finland (EGoF) and in the Neva Bay. The biotic and abiotic components of deposit sites ecosystems were observed there in 1999-2019, with using standard monitoring methods, in order to reveal effects of dumping on hydrobiologic communities and to determine their environmental status. The Biota Condition Index for 6 deposit sites was calculated and compared to areas which are not stressed by dumping. It is shown that the biological communities (especially – benthic) in the deposit sites areas are enormous not-sustainable and start their succession from the zero point every time after repeating stressing effect of dumping.

ASSESSMENT OF THE SPATIOTEMPORAL DYNAMICS OF THE MACROPHYTE THICKET ECOSYSTEMS IN THE NEVA BAY AND THE ADJACENT WATERS OF THE EASTERN GULF OF FINLAND

2017 ◽  
Author(s):  
Ekaterina Maksimova ◽  
Ekaterina Maksimova ◽  
Vladimir Zhigulsky ◽  
Vladimir Zhigulsky ◽  
Vladimir Shuisky ◽  
...  
Keyword(s):  
Aquatic Vegetation ◽  
Temporal Dynamics ◽  
Negative Impact ◽  
Spatiotemporal Dynamics ◽  
Gulf Of Finland ◽  
Active Growth ◽  
Nesting Sites ◽  
Significant Negative Impact ◽  
And Migration ◽  
Neva Bay

The macrophyte thicket ecosystems of higher aquatic vegetation in the Neva Bay (NB) and Eastern Gulf of Finland (EGoF) perform many important roles, including acting as the habitats, nesting sites and migration sites for aquatic and semi-aquatic birds, creating the specific conditions necessary for the spawning and growth of many species of fish, and taking part in the self-purification of the aquatic ecosystems. Many anthropogenic disturbances, hydraulic works in particular, have a significant negative impact on these macrophyte thicket ecosystems. In recent years, the active growth of a new type of macrophyte thicket has been observed in the NB. This is due to the aftereffects of the construction of the Saint Petersburg Flood Prevention Facility Complex (FPFC). It is quite likely that the total macrophyte thicket area in these waters is currently increasing. In the future, it will be necessary to assess the environmental impacts of the hydraulic works on the macrophyte thicket of the NB and EGoF, taking into account the background processes of the spatiotemporal dynamics of the reed beds in the waters in question. To do this, it will be necessary to carry out a comprehensive study of these ecosystems and identify patterns in their spatial and temporal dynamics. The program of the study has been developed and is currently being implemented by Eco-Express-Service, a St. Petersburg eco-design company.

PROBLEM OF HEAVY METAL SURFACE SEDIMENT CONTAMINATION IN THE EASTERN GULF OF FINLAND

2017 ◽  
Author(s):  
N Derugina ◽  
N Derugina ◽  
А Grigoriev ◽  
A Grigoriev ◽  
Дарья Рябчук ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Bottom Sediments ◽  
Late Holocene ◽  
Sediment Contamination ◽  
Gulf Of Finland ◽  
Slow Decline ◽  
Contamination Levels ◽  
The Gulf Of Finland ◽  
Neva Bay

This project defines the pre-industrial quantities of heavy metals in sediment sequences of the Late Holocene from the Eastern Gulf of Finland. A comparative analysis reveals differences and similarities in the current concentrations of heavy metals in bottom sediments and pre-industrial levels. It is found that the maximum concentrations of heavy metals in the bottom sediments of the Gulf of Finland and Neva Bay occurred in the period of 1950-1990. Since the 1990s, the trend has been a slow decline in the contamination levels; however, the concentrations of some heavy metals in bottom sediments remain high.

scholarly journals EXPERIMENTAL STUDIES OF PILE FOUNDATION GROUND BASE REINFORCED WITH HARD INCLUSIONS

2019 ◽  
Vol 10 (3) ◽  
pp. 5-15
Author(s):  
M. L Nuzhdin
Keyword(s):  
High Pressure ◽  
Pile Foundation ◽  
Experimental Studies ◽  
Pile Foundations ◽  
Foundation Model ◽  
Series Of Experiments ◽  
Bored Piles ◽  
Soil Foundation ◽  
High Pressure Injection ◽  
The Impact

Often in construction practice there is a need to strengthen the pile foundation of buildings and structures. The traditional methods include the implementation of additional, as a rule, bored piles with the subsequent erection of a grillage incorporating them into operation. Often, this work has to be done in the conditions of dense urban development, in cramped rooms of the basement, etc., which leads to significant technological difficulties. One of the alternative ways to strengthen pile foundations is the method of high-pressure group injection, which consists in injecting a movable cement-sand mortar into the soil under pressure that exceeds its structural strength. As a result, after its hardening, solid injection bodies are formed at the base, reinforcing the soil base. The article describes the results of experiments to assess the impact of the layout of hard inclusions on the deformability of the soil foundation of the pile foundation model. The experiments were carried out in a small soil tray, which was filled with medium-grained loose sand. The piles were modeled with metal rods, the pile grillage with a metal square stamp. The pile foundation model included 9 piles arranged in a square grid. As injection bodies, gravel grains of various sizes and shapes were used. The studies included 10 series of experiments (each experiment was repeated at least 3 times): the volume of the inclusions used, their sizes, the positioning step in the plan and in depth varied. As a result of the analysis of the performed experiments, conclusions were formulated regarding the purpose of the optimal layout of hard inclusions when strengthening the soil foundation of pile foundations by high-pressure injection of mobile cement-sand mixtures.

THE USE OF BIOTECHNOLOGY IN THE PREVENTION OF FAILURE IN THE IMPOSITION OF SMALL INTESTINAL ANASTOMOSES IN THE EXPERIMENT

2020 ◽  
pp. 87-91
Author(s):  
M. Tymchenko ◽  
Yu. Ivanova ◽  
V. Padalko ◽  
H. Sheremet ◽  
O. Kozlova ◽  
...  
Keyword(s):  
Mucous Membrane ◽  
Intestinal Mucosa ◽  
Intestinal Anastomosis ◽  
Experimental Studies ◽  
Operating Conditions ◽  
Laboratory Animals ◽  
Control Group ◽  
Intestinal Anastomoses ◽  
Series Of Experiments ◽  
Immunohistochemical Studies

Summary. The aimof the study is to develop a method of sealing the sutured of the small intestine anastomosis in conditions of high risk anastomosis leakege by stopping the inflammation’ cascade in experiment. Materials and methods.The work was experimental in nature, was performed in the SI «ZIGUS NAMSU» in collaboration with the Scientific Research Institute of Biology V. N. Karazin KhNU in the period from 2018 to 2019. To increase the tightness of the intestinal anastomoses applied under conditions of laparatomy, experimental studies were conducted on laboratory animals. The studies were carried out after the permission of the ethics committee SI «ZIGUS NAMSU» in compliance with all ethical requirements for the humane treatment of animals.Surgical operations in two series of experiments were performed under operating conditions under general anesthesia on 10 white sexually mature linear rats – Wistar males, 12-18 months old, weighing about 250 grams. All morphological material (the first and second series of experiments) was marked and fixed in a 10% solution of neutral formalin. Subsequently, paraffin sections were prepared according to the generally accepted histotechnical method and stained with hematoxylin - eosin; according to Van Gieson and Mallory, an immunohistochemical study was used to study microenvironment factors. Results and Discussion. Immunohistochemical examination of the intestine was carried out in several stages, at the first stage we took intestinal tissue during the surgery to form the intestinal anastomosis, before the introduction of allogeneic cell transplants. Also carried out immunohistochemical studies of the emerging mucous membrane at various times after the formation of insolvency of intestinal anastomoses in both studied groups. When using a cell allograft, the mechanisms of repair of the intestinal mucosa include the appearance of cells that carry the expression of markers of mesenchymal and epithelial differentiation (Vim, CD34, CKW, Ecad), and are usually localized in the walls of blood vessels of granulation tissue, as well as in areas of the repairing epithelium. In addition, in the main group, only 7 days after the reaction to cytokeratins (CKW) and Ecad, areas of the repairing epithelium were detected, while the visualization of the epithelium in the control group did not begin even after 10 days. The analysis of immunophenotypes of repairing cells allows us to suggest the participation of mesenchymal-epithelial transformation mechanisms in this process. Conclusions.Thus, studies have shown that the use of cell transplantation of culture of allogeneic cells of the intestine leads to the reconstruction of the intestinal mucosa in a fairly short time. Conducted histological and immunohistochemical studies showed that in the vast majority of animals (77.2%) 10-14 days after the operation, an almost unchanged mucous membrane forms with the preservation of its elasticity.

scholarly journals Analisys of experimental studies of optimal control of tower crane trolley movement mechanism

2020 ◽  
Vol 11 (4) ◽  
pp. 5-12
Author(s):  
V. S. Loveikin ◽  
◽  
Yu. O. Romasevych ◽  
O. V. Stekhno ◽  
◽  
...  
Keyword(s):  
Optimal Control ◽  
Data Collection ◽  
Experimental Studies ◽  
Poor Quality ◽  
Laboratory Model ◽  
Recording Equipment ◽  
Factors Affecting ◽  
Tower Crane ◽  
Series Of Experiments ◽  
Frequency Inverter

The article describes the laboratory model of the tower crane boom system, measuring and recording equipment (sensors, data collection system, power supply, etc.), power control equipment (frequency inverter), and software for data collection and for the frequency inverter control. Planning of experiments for investigation of optimal control of lab model movement was carried out. All experiments are divided into two series: for time optimal control and for control optimal by the integral criterion. For the first series of experiments, the weight of the load (has been varied at three levels) and the length of the flexible suspension (has been varied at two levels) acted as independent factors. For the second series of experiments, one more independent factor was taken into account ‒ the duration of the trolley acceleration (deceleration). This factor has been varied at three levels. The analysis of experimental studies was carried out in terms of variation indicators (deviation of theoretical and experimental data) and graphical dependencies. The results of the analysis showed a sufficiently high convergence of the data obtained during the experiments with those that were obtained by calculation. The existing deviations are caused by the inaccuracy of setting the parameters of the system, the failure to take into account all the significant factors affecting the movement of the system, as well as poor-quality implementation of control with rapid changes in the speed of the trolley movement. Recommendations are given that will eliminate the described factors and ensure further improvement of the technique for implementing optimal control in practice

scholarly journals New data on the flora of Centrophyceae (Bacillariophyta) in the Neva Bay of the Gulf of Finland (Russia)

Algologia ◽  
2021 ◽  
Vol 31 (4) ◽  
pp. 382-389
Author(s):  
S.I. Genkal ◽  
◽  
I.S. Trifonova ◽  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Microscopy Study ◽  
Systematic Position ◽  
Electron Microscopy Study ◽  
Gulf Of Finland ◽  
Centric Diatoms ◽  
The Gulf Of Finland ◽  
Neva Bay ◽  
Scanning Electron

This scanning electron microscopy study of phytoplankton from the Neva Bay and analysis of valve images from S.I. Genkal’s iconotheka have provided new data on centric diatoms of the Neva Bay. Representatives of the genera Aulacoseira scalaris and Stephanodiscus lacustris, new to the flora of the Bay, have been identified. The systematic position and distribution of 14 species and varieties of Centrophyceae from the genera Aulacoseira, Conticribra, Cyclostephanos, Ellerbeckia, Handmannia, Pantocsekiella, Stephanodiscus, Thalassiosira have been refined and specified. The species composition of the class Centrophyceae of the Neva Bay has been expanded. Now it includes 42 species and varieties from 17 genera.

scholarly journals RESULTS OF EXPERIMENTAL STUDIES OF THE CHILDREN’S AXIAL PUMP «DON-3»

2018 ◽  
Vol 20 (2) ◽  
pp. 61-68 ◽  
Author(s):  
G. P. Itkin ◽  
O. Yu. Dmitrieva ◽  
A. S. Buchnev ◽  
A. A. Drobyshev ◽  
A. P. Kuleshov ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Left Ventricle ◽  
Experimental Studies ◽  
Acid Base Balance ◽  
Acid Base ◽  
Histological Studies ◽  
Axial Pump ◽  
Base Balance ◽  
Series Of Experiments

Aim.To evaluate the functioning of an implantable pediatric axial pump «DON-3» for bypassing the left ventricle of the heart in experiments on sheep.Materials and methods. Five sheeps at the age of 12–18 months performed paracorporeal installation of the children’s axial pump «DON-3» according to the scheme «left ventricle – aorta».Results.A technique was developed and 5 chronic experiments were conducted on sheep to assess the model of the children’s axial pump «DON-3». The duration of the experiments in this series averaged 9 ± 5 days. The main indicators of hemodynamics, acid-base balance were within the norm. Conducted morphological and histological studies of the kidneys, liver and lungs did not reveal the presence of zones of ischemia and thromboembolism.Conclusion.The results of this series of experiments showed satisfactory results, suggesting further research on the development of prototypes of a pediatric pump for clinical practice. 

PROBLEM OF HEAVY METAL SURFACE SEDIMENT CONTAMINATION IN THE EASTERN GULF OF FINLAND

2017 ◽  
Author(s):  
N Derugina ◽  
N Derugina ◽  
А Grigoriev ◽  
A Grigoriev ◽  
Дарья Рябчук ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Bottom Sediments ◽  
Late Holocene ◽  
Sediment Contamination ◽  
Gulf Of Finland ◽  
Slow Decline ◽  
Contamination Levels ◽  
The Gulf Of Finland ◽  
Neva Bay

This project defines the pre-industrial quantities of heavy metals in sediment sequences of the Late Holocene from the Eastern Gulf of Finland. A comparative analysis reveals differences and similarities in the current concentrations of heavy metals in bottom sediments and pre-industrial levels. It is found that the maximum concentrations of heavy metals in the bottom sediments of the Gulf of Finland and Neva Bay occurred in the period of 1950-1990. Since the 1990s, the trend has been a slow decline in the contamination levels; however, the concentrations of some heavy metals in bottom sediments remain high.

USING OF MULTI-YEAR REMOTE SENSING DATA FOR THE NEVA BAY AND THE EASTERN GULF OF FINLAND FOR REVEALING PECULIARITIES OF ANTHROPOGENIC IMPACTS OF HYDRO-TECHNICAL FACILITIES BUILDING AND DREDGINGS ON THE COASTAL AND WATER ENVIRONMENT

2017 ◽  
Author(s):  
Leontina Sukhacheva ◽  
Leontina Sukhacheva
Keyword(s):  
Remote Sensing ◽  
Coastal Water ◽  
Anthropogenic Impacts ◽  
Water Environment ◽  
Water Dynamics ◽  
Spatiotemporal Variability ◽  
Gulf Of Finland ◽  
Anthropogenic Factors ◽  
Neva Bay

This paper is devoted to the use of long-term remote sensing (RS) data for assessment of anthropogenic impacts on the coastal water environment of the Neva Bay (NB) and the eastern part of the Gulf of Finland (EGOF), caused by construction of hydro-ingineering facilities, operations for land reclamation, dredging and underwater dumping. The study period includes past four decades for which airborne and satellite data are available. Results of using long-term RS data sets for monitoring and studying coastal water environment, for estimation of levels of water contamination by suspended matter (SM), for revealing spatiotemporal variability of SM distribution under the influence of natural and anthropogenic factors, for studying features of surface water dynamics and of phytoplankton development, are discussed.

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