scholarly journals Characteristics of physiological adaptation of human under various residence modes in normobaric hypoxic environment reducing the fire hazard of navy objects

2020 ◽  
Vol 6 (2) ◽  
pp. 49-58
Author(s):  
A. O. Ivanov ◽  
V. F. Belyaev ◽  
A. Yu. Eroshenko ◽  
A. A. Tanova ◽  
D. V. Shatov ◽  
...  
Keyword(s):  
Oxygen Content ◽  
Fire Safety ◽  
Gradual Increase ◽  
Fire Hazard ◽  
Physiological Adaptation ◽  
Resistance To Hypoxia ◽  
Adaptive Changes ◽  
Hypoxic Conditions ◽  
Hypoxic Environment ◽  
Gas Environment

Purpose is an increasing the fire hazard of sealed inhabitated Navy objects through the creation of normobaric hypoxic breathable gas environment.Materials and methods. In the first series of studies, 6 men (22–53 years) daily, for four hours, for 60 days were in the environment of the following content: [O2]=16–17%, [СO2]=0,3–0,8%, N2 — the rest. In the second series of studies, 6 men (25– 53 years) continuously for 100 days were in the environment of the following content: [O2]=19%, [СO2]=0,3–0,8%, N2 — the rest. Daily, for 4 hours, men of the second group performed works in the environment with the oxygen content of 16–17%.Results and discussion. Stay in hypoxic environments did not lead to «failure of adaptation” in any of the examined. A gradual increase in resistance to hypoxia was observed due to adaptive changes, greater in individuals who were continuously in hypoxic conditions.Conclusion. The results of the work confirm the perspectiveness of using hypoxic environments in the tested modes to increase the fire safety of the energy-rich inhabited objects of the Navy.

Model for assigning security objects to a specific risk category in the field of fire safety

2020 ◽  
Vol 90 ◽  
pp. 19-31
Author(s):  
D. V. Zobkov ◽  
◽  
A. A. Poroshin ◽  
A. A. Kondashov ◽  
◽  
...  
Keyword(s):  
Adverse Effects ◽  
Fire Safety ◽  
Economic Activity ◽  
Fire Hazard ◽  
Risk Category ◽  
Negative Consequences ◽  
Acceptable Risk ◽  
Individual Object ◽  
Safety Requirements ◽  
Risk Categories

Introduction. A mathematical model is presented for assigning protection objects to certain risk categories in the field of fire safety. The model is based on the concepts of the probability of adverse effects of fires causing harm (damage) of various extent and severity to the life or health of citizens, and the acceptable risk of harm (damage) from fires. Goals and objectives. The purpose of the study is to develop the procedure for assigning protection objects to a certain category of risk of harm (damage) based on estimates of the probability of fires with the corresponding severity consequences, to determine the acceptable level of risk of harm (damage) due to the fires, to calculate and develop numerical values of criteria for assigning objects of protection to the appropriate risk categories. Methods. The boundaries of the intervals corresponding to certain risk categories are determined by dividing the logarithmic scale of severity of adverse effects of fires into equal segments. Classification methods are used to assign objects of protection to a specific risk category. Results and discussion. Based on the level of severity of potential negative consequences of a fire, risk categories were determined for groups of protection objects that are homogeneous by type of economic activity and by functional fire hazard classes. The risk category for each individual object of protection is proposed to be determined using the so-called index of "identification of a controlled person" within a group of objects that are homogeneous by type of economic activity and class of functional fire hazard. Depending on the risk category, the periodicity of planned control and supervision measures in relation to the specific object of protection under consideration is determined, taking into account its socio-economic characteristics and the state of compliance with fire safety requirements by the controlled person. Conclusions. To develop criteria for classifying protection objects that are homogeneous in terms of economic activity and functional fire hazard classes, the probability of negative consequences of fires, that are causing harm (damage) of various extent and severity to the life or health of citizens, and the acceptable risk of causing harm (damage) as a result of fires, is used. The risk category for each individual object of protection is determined taking into account socio-economic characteristics of the object that affect the level of ensuring its fire safety, as well as the criteriaof integrity of the subordinate person that characterize the probability of non-compliance with mandatory fire safety requirements at the object of protection. Calculations are made and numerical values of criteria for assigning protection objects that are homogeneous in terms of economic activity and functional fire hazard classes to a certain category of risk are proposed. Key words: object of protection, probability of fire, acceptable level of risk, risk category, dangerous factor of fire, death and injury of people.

scholarly journals Self-Generated Hypoxia Leads to Oxidative Stress and Massive Death in Ustilago maydis Populations under Extreme Starvation and Oxygen-Limited Conditions

2021 ◽  
Vol 7 (2) ◽  
pp. 92
Author(s):  
Jelena Petkovic ◽  
Milorad Kojic ◽  
Mira Milisavljevic
Keyword(s):  
Oxidative Stress ◽  
Pure Water ◽  
Ustilago Maydis ◽  
Oxygen Species ◽  
Hypoxic Conditions ◽  
Hypoxic Environment ◽  
Cellular Factors ◽  
Catastrophic Loss ◽  
Initial Culture ◽  
Response To Water

Ustilago maydis and Saccharomyces cerevisiae differ considerably in their response to water-transfer treatments. When stationary phase cells were transferred to pure water and incubated under limited supply of oxygen, the U. maydis cells suffered a catastrophic loss of viability while the S. cerevisiae population was virtually unaffected by the treatment. The major factor underlying the death of the U. maydis cells under those conditions was an oxygen-consuming cellular activity that generated a hypoxic environment, thereby inducing oxidative stress and accumulation of reactive oxygen species, which resulted in lethality. Importantly, a small residue of U. maydis cells that did survive was able to resume growth and repopulate up to the initial culture density when sufficient aeration was restored. The regrowth was dependent on the cellular factors (Adr1, Did4, Kel1, and Tbp1), previously identified as required for repopulation, after killing with hydrogen peroxide. Surprisingly, the survivors were also able to resume growth under apparently hypoxic conditions, indicating that these remnant cells likely switched to a fermentative mode of growth. We discuss the findings in terms of their possible relevance to the eco-evolutionary adaptation of U. maydis to risky environments.

scholarly journals FIRE RESISTANCE OF BUILDING STRUCTURES OF FLAMMABLE AND COMBUSTIBLE LIQUIDS STORES

Fire Safety ◽  
2019 ◽  
pp. 5-9
Author(s):  
O. I. Bashynskiy ◽  
M. Z. Peleshko ◽  
T. G. Berezhanskiy
Keyword(s):  
Fire Resistance ◽  
Fire Safety ◽  
Theoretical Calculations ◽  
Fire Hazard ◽  
Building Structures ◽  
Safety Measures ◽  
Normative Documents ◽  
Size Number ◽  
Literary Sources ◽  
Combustible Liquids

The article is dedicated to the fire resistance limit of building structures of the objects for the storage of flammable and combustible liquids. Today, oil stores are very important elements of the oil supply system in Ukraine. The analysis of literary sources has shown that fires in oil stores cause extra fire hazard of surrounding objects. Increasing of their scales requires further improvement of fire safety measures during planning and using of oil stores. Fires in such buildings are tricky and large; they cause great harm and often lead to the death of people; their liquidation is very difficult. Theoretical calculations shown that the collapse of structures of the packaged oil stores and, as a result, significant material losses and the threat to people's life and health, were resulted from the incorrect selection of building structures and the discrepancy between the fire resistance of these structures and the applicable norms and requirements for such buildings. Fire Safety, №34, 2019 9 Fire resistance limit of the metal double-T pillar made of steel ВСт3пс4 (profile size number 30) was calculated in the article. Such constructions are used in oil stores. The obtained fire resistance limit of a metal double-T pillar is about 16 minutes (R 16). According to the normative documents for buildings of this type (the degree of fire resistance of the building – III), it should be 120 minutes (R 120). Even if the calculation method has an error due to the choice of another steel grade, objectively none of the double-T profiles from the assortment list would provide proper fire resistance limit.

Methodology for assigning objects of protection to a certain risk category in the field of fire safety

2020 ◽  
pp. 26-35
Author(s):  
Денис Валерьевич Зобков ◽  
Александр Алексеевич Порошин ◽  
Андрей Александрович Кондашов ◽  
Евгений Васильевич Бобринев ◽  
Елена Юрьевна Удавцова
Keyword(s):  
Fire Safety ◽  
Economic Activity ◽  
Fire Hazard ◽  
Fire Risk ◽  
Federal State ◽  
Risk Category ◽  
Negative Consequences ◽  
Fire Hazards ◽  
Risk Categories

Проанализирован международный опыт реформирования проверок соблюдения требований пожарной безопасности и внедрения риск-ориентированного подхода. Разработана модель отнесения объектов защиты к категориям риска в зависимости от вероятного причинения вреда, который рассчитывается исходя из количества погибших и травмированных при пожарах людей. Сформулированы критерии отнесения объектов защиты к категориям риска. Выполнен расчет категорий риска для групп объектов, однородных по группам экономической деятельности и классам функциональной пожарной опасности. Проведено сравнение с существующей классификацией объектов защиты по категориям риска. The international experience of reforming of fire safety compliance checks and implementing a risk-based approach is considered. There are presented methodological approaches to calculating the risk of causing harm (damage) in buildings (structures) as a result of fire for the purpose of assignment of buildings and structures according to risk categories as well as justification of the frequency of scheduled inspections at these facilities. There is calculated the probability of fire occurrence for a group of objects of protection that are homogeneous by type of economic activity and functional fire hazard classes in order to assign objects of protection to certain risk categories. The social damage expressed in the death and injury of people as a result of fire is also calculated in order to assign objects of protection to certain risk categories. Classification of objects of protection according to the risk categories is performed using the indicator of the severity of potential negative consequences of fires. This indicator characterizes the degree of excess of the expected risk of negative consequences of fires for the corresponding group of objects of protection in relation to the value of the permissible risk of negative consequences of fire. The permissible risk of negative consequences of fires is calculated on the basis of statistical data, taking into account the value of the individual fire risk of exposure of critical values of fire hazards on person in buildings and structures. The criteria for assigning groups of objects of protection to the appropriate risk categories are formulated on the basis of formation of distribution of numerical values of the severity of potential negative consequences of fires. There are carried out the assessment of the severity of potential negative consequences of fires for objects of protection that are homogeneous by type of economic activity and functional fire hazard classes, and also the risk categories of the corresponding groups of objects are determined. The proposed classification of objects of protection according to risk categories is compared with the existing classification. The obtained results of calculations showed that scheduled inspections of objects of protection by the Federal state supervision bodies, depending on the assigned risk category and with corresponding frequency, have significant role in improving the level of fire safety of objects. The decrease in the intensity of scheduled inspections, at the same time, may lead to a corresponding decrease in the level of fire protection of objects.

scholarly journals Hypoxia Shapes Autophagy in LPS-Activated Dendritic Cells

2020 ◽  
Vol 11 ◽  
Author(s):  
Sara Monaci ◽  
Carlo Aldinucci ◽  
Daniela Rossi ◽  
Gaia Giuntini ◽  
Irene Filippi ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Human Monocyte ◽  
Bafilomycin A1 ◽  
Adaptive Responses ◽  
Protein Levels ◽  
Hypoxic Conditions ◽  
Hypoxic Environment ◽  
Tlr4 Ligand ◽  
Autophagic Process ◽  
Lps Treatment

During their lifespan, dendritic cells (DCs) are exposed to different pO2 levels that affect their differentiation and functions. Autophagy is one of the adaptive responses to hypoxia with important implications for cell survival. While the autophagic machinery in DCs was shown to impact signaling of TLRs, its regulation by the MD-2/TLR4 ligand LPS is still unclear. The aim of this study was to evaluate whether LPS can induce autophagy in DCs exposed to either aerobic or hypoxic conditions. Using human monocyte-derived DCs and the combination of immunofluorescence confocal analysis, measure of mitochondrial membrane potential, Western blotting, and RT-qPCR, we showed that the ability of LPS to modulate autophagy was strictly dependent upon pO2 levels. Indeed, LPS inhibited autophagy in aerobic conditions whereas the autophagic process was induced in a hypoxic environment. Under hypoxia, LPS treatment caused a significant increase of functional lysosomes, LC3B and Atg protein upregulation, and reduction of SQSTM1/p62 protein levels. This selective regulation was accompanied by activation of signalling pathways and expression of cytokines typically associated with DC survival. Bafilomycin A1 and chloroquine, which are recognized as autophagic inhibitors, confirmed the induction of autophagy by LPS under hypoxia and its impact on DC survival. In conclusion, our results show that autophagy represents one of the mechanisms by which the activation of the MD-2/TLR4 ligand LPS promotes DC survival under hypoxic conditions.

scholarly journals PERSPECTIVES FOR THE APPLICATION OF VARIOUS FIRE-SAFE GAS MEDIA ON THE INHABITED SEALED OBJECTS OF THE NAVY

2019 ◽  
Vol 5 (4) ◽  
pp. 91-98
Author(s):  
A. Yu. Eroshenko ◽  
V. A. Petrov ◽  
A. O. Ivanov ◽  
V. A. Stepanov ◽  
O. V. Lobozova ◽  
...  
Keyword(s):  
Fire Safety ◽  
Working Capacity ◽  
Mental Performance ◽  
Initial State ◽  
Male Volunteers ◽  
Hypoxic Environment ◽  
Maximum Decrease ◽  
Gaseous Media ◽  
Group 2 ◽  
Group 1

Introduction. The need to ensure trouble-free operation of inhabited sealed objects of the Navy requires continuous improvement of technologies to increase their fire safety. Such technologies include the creation of hypoxic gas media at facilities that reduce the risk of fires and ensure the possibility of personnel staying in them. The purpose of the work is a comparative assessment of changes in the maximum human working capacity during continuous stay in various normobaric hypoxic environments, promising to increase the fire safety of sealed inhabited objects of the Navy. Materials and methods. In the 1st series of studies, 100 daily sealing of 6 male volunteers (28–53 years old) in controlled hypoxic environments was carried out: [O2] in the premises of permanent residence — 18–19%, periodic (4 hours per day) stay — 16–17%/ In the 2nd series of studies, 6 male volunteers (age 25–51 years) were continuously in argon-containing gas media with [O2]=13,5–14,5%, [Ar]=30–35% for 60 days. During the studies, the dynamics of the mental (operator) and maximum physical working capacity of the subjects were evaluated. Results. Stay in hypoxic environments was accompanied by a decrease in the working capacity of volunteers. The relative degree of negative changes in mental performance in group 1 did not exceed –7%, in group 2 — –10% of the initial level; the maximum decrease in physical performance in group 1 was on average about — –11%, in group 2 — –17% compared with the initial state, which does not go beyond the permissible limits. Conclusion. The introduction of tested gaseous media at naval facilities is promising. The choice of the composition of the gas mixture should be determined by the degree of risk of fires at a particular facility, the technical capabilities of creating and maintaining a hypoxic environment of optimal composition, the number and state of health of the crew.

scholarly journals Survey on Existing High-Rise Building Fire Safety Assessment Based on Fire Compartment and Fire Protection System Maintenance

2020 ◽  
Vol 34 (6) ◽  
pp. 72-78
Author(s):  
Doo Chan Choi ◽  
Hak Kyung Kim ◽  
Min Hyeok Ko ◽  
In Tae Kim ◽  
Hyun Soo Hwang
Keyword(s):  
Performance Evaluation ◽  
Fire Safety ◽  
Safety Assessment ◽  
Fire Hazard ◽  
Safety Performance ◽  
Safety Standards ◽  
High Rise ◽  
Hazard Response ◽  
System Maintenance ◽  
Survey Results

Advanced fire safety standards and laws are being applied to new high-rise buildings, but existing high-rise buildings are maintained and managed based on previous fire safety standards, which makes them weak to fire hazard response. This study was conducted to evaluate the survey results for the maintenance status of fire compartments and principal firefighting facilities of 157 buildings using the performance evaluation table for fire safety of existing high-rise buildings. This paper presents actual problems in the maintenance of fire compartments and firefighting facilities of existing high-rise buildings. In addition, it provides reference materials that can be used to establish policies for supplementing the fire safety performance the buildings in the future.

scholarly journals FACTORS OF FIRE HAZARD OF ELECTRICITY-GENERATING EQUIPMENT

Fire Safety ◽  
2019 ◽  
pp. 43-46
Author(s):  
I. P. Kravets ◽  
O. I. Bashynskiy ◽  
A. P. Kushnir ◽  
O. V. Shapovalov
Keyword(s):  
Fire Safety ◽  
Fire Hazard ◽  
Short Circuit ◽  
Electric Energy ◽  
Electrical Equipment ◽  
Correct Choice ◽  
Main Task ◽  
Prevention Measures ◽  
Strict Adherence ◽  
Generating Equipment

The article deals with the problems of fire hazard of electricity-generating equipment during their exploitation. Intensive electrification of industrial and residual objects leads to the saturation of these objects with different electricity-generating equipment. Functioning of such equipment is accompanied with high heat emission and contains significant fire hazard. The electric current in an electrical conductor produces heat, when electric energy turns into thermal. All electrical equipment must be produced in strict adherence to fire safety rules and requirements. Ignoring these requirements causes heating of conductors through all the length, spunking of isolation, sparkling and, as a result, breaking-out of fire. Therefore, reducing the probability of fire even in the cases of abnormal work, wrong exploitation and foreseen refuses is the main task during planning and exploitation of electrical equipment and also during selection of structural materials. The primary purpose of fire prevention measures in the electrical equipment is avoiding of its self-ignition, and localization of fire after the self-ignition of electricity-generating equipment. Fire safety during exploitation of electricity-generating equipment depends on its technical state. Correct choice of conductor cross section is very important. Protection stage of electrical equipment, type of wiring, and cable laying method must comply with environmental conditions and have the proper climatic implementation and placement category. Proper protective devices from a short circuit and overloads must be used. Their operating values must be also foreseen. All above-mentioned measures prevent fires and explosions during exploitation of electrical equipment. Key

scholarly journals Normative regulation of fire safety of infrastructural objects of hydrogen energetics

2020 ◽  
Vol 29 (5) ◽  
pp. 5-12
Author(s):  
Yu. N. Shebeko
Keyword(s):  
Liquid Phase ◽  
Fire Safety ◽  
Fire Hazard ◽  
Energy Generation ◽  
Normative Documents ◽  
Practical Applications ◽  
Safety Requirements ◽  
Production Of Hydrogen ◽  
Normative Basis ◽  
Hydrogen Energetics

Introduction. Now many countries produce measures for a transfer of their economics to an application of a hydrogen energetics. Because of a high fire hazard of hydrogen a fire safety provision of infrastructural objects of the hydrogen energetics is a very important task. The infrastructural objects of the hydrogen energetics are the facilities aimed on a production and storage of hydrogen, transportation of gaseous (GH2) and liquid (LH2) hydrogen, an application of hydrogen for an energy generation, car refueling stations etc. Scientific basis for a creation of the fire safety normative documents was laid in studies of Russian and foreign investigators.Russian normative documents. Russian normative documents in the area considered are analyzed in this work. A draft of the Technical Regulation on a safety of the facilities aimed on production, storage, transportation and application of hydrogen is the most important among them. This document contains a lot of specific requirements which should be used independently of a type of the hydrogen facility. Therefore this document can be considered as extremely “rigid” for a practical applications. A set of rules SP 162.1330610.2014 is aimed on the regulation of the safety requirements for the facilities using liquid hydrogen. The document PB 03-598-03 considers the safety requirements for a production of hydrogen by an electrolysis of water. A conclusion was made that Russian normative basis is not sufficient for a development of the hydrogen energetics.Standard NFPA 2. The standard NFPA 2 can be considered as a most important normative document containing the safety requirements for the facilities for production, storage, transportation and application of hydrogen in a gaseous and a liquid phase. This standard contains both general and specific requirements for the infrastructural objects such as car refueling stations, storages of hydrogen in the gaseous and the liquid phase and also using metal hydrides, hydrogen production facilities, energy generation objects using hydrogen, technological equipment containing hydrogen, laboratory facilities, car parks for the cars using hydrogen as a fuel etc.Conclusions. It was found that there is no comprehensive set of the normative documents regulating fire safety of infrastructural objects of hydrogen energetics. The series of the Russian normative documents in this area which should be created was proposed. A conclusion was made that the requirements of NFPA 2 can be used at a creation of the Russian normative basis of the hydrogen energetics.

scholarly journals The influence of hypoxia on the prostate cancer proteome

2020 ◽  
Vol 58 (6) ◽  
pp. 980-993 ◽  
Author(s):  
James A. Ross ◽  
Johannes P.C. Vissers ◽  
Jyoti Nanda ◽  
Grant D. Stewart ◽  
Holger Husi ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Western Europe ◽  
Cancer Cell Line ◽  
Prostate Cancer Cell Line ◽  
Differentially Expressed ◽  
Multivariate Statistical ◽  
Data Independent Acquisition ◽  
Hypoxic Conditions ◽  
Hypoxic Environment ◽  
The Impact

AbstractProstate cancer accounts for around 15% of male deaths in Western Europe and is the second leading cause of cancer death in men after lung cancer. Mounting evidence suggests that prostate cancer deposits exist within a hypoxic environment and this contributes to radio-resistance thus hampering one of the major therapies for this cancer. Recent reports have shown that nitric oxide (NO) donating non-steroidal anti-inflammatory drugs (NSAIDs) reduced tumour hypoxia as well as maintaining a radio-sensitising/therapeutic effect on prostate cancer cells. The aim of this study was to evaluate the impact of hypoxia on the proteome of the prostate and to establish whether NO-NSAID treatment reverted the protein profiles back to their normoxic status. To this end an established hormone insensitive prostate cancer cell line, PC-3, was cultured under hypoxic and normoxic conditions before and following exposure to NO-NSAID in combination with selected other common prostate cancer treatment types. The extracted proteins were analysed by ion mobility-assisted data independent acquisition mass spectrometry (MS), combined with multivariate statistical analyses, to measure hypoxia-induced alterations in the proteome of these cells. The analyses demonstrated that under hypoxic conditions there were well-defined, significantly regulated/differentially expressed proteins primarily involved with structural and binding processes including, for example, TUBB4A, CIRP and PLOD1. Additionally, the exposure of hypoxic cells to NSAID and NO-NSAID agents, resulted in some of these proteins being differentially expressed; for example, both PCNA and HNRNPA1L were down-regulated, corresponding with disruption in the nucleocytoplasmic shuttling process.

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