Optimization of the safety margin to the critical load of the heat-releasing assemblies in a high-powered water-cooled channel reactor (RBMK)

1979 ◽  
Vol 46 (4) ◽  
pp. 262-267
Author(s):  
S. V. Bryunin ◽  
A. I. Gorelov ◽  
V. Ya. Novikov ◽  
I. K. Pavlov ◽  
V. V. Postnikov
2008 ◽  
Vol 44 ◽  
pp. 11-26 ◽  
Author(s):  
Ralph Beneke ◽  
Dieter Böning

Human performance, defined by mechanical resistance and distance per time, includes human, task and environmental factors, all interrelated. It requires metabolic energy provided by anaerobic and aerobic metabolic energy sources. These sources have specific limitations in the capacity and rate to provide re-phosphorylation energy, which determines individual ratios of aerobic and anaerobic metabolic power and their sustainability. In healthy athletes, limits to provide and utilize metabolic energy are multifactorial, carefully matched and include a safety margin imposed in order to protect the integrity of the human organism under maximal effort. Perception of afferent input associated with effort leads to conscious or unconscious decisions to modulate or terminate performance; however, the underlying mechanisms of cerebral control are not fully understood. The idea to move borders of performance with the help of biochemicals is two millennia old. Biochemical findings resulted in highly effective substances widely used to increase performance in daily life, during preparation for sport events and during competition, but many of them must be considered as doping and therefore illegal. Supplements and food have ergogenic potential; however, numerous concepts are controversially discussed with respect to legality and particularly evidence in terms of usefulness and risks. The effect of evidence-based nutritional strategies on adaptations in terms of gene and protein expression that occur in skeletal muscle during and after exercise training sessions is widely unknown. Biochemical research is essential for better understanding of the basic mechanisms causing fatigue and the regulation of the dynamic adaptation to physical and mental training.


2015 ◽  
pp. 86-99 ◽  
Author(s):  
E. Avraamova ◽  
T. Maleva

The loss of country’s socio-economic development stability puts on the agenda the problem of finding solutions contributing to the maintenance of Russian households’ welfare. The authors believe that these solutions lie in the broader area than applying various instruments of monetary support. The most effective solutions are related to the actualization of own resources of households that can act as a safety margin as well as a source of social development. The attempt to evaluate the households’ resource provision and highlight the significance of each resource enabling or creating barriers to the growth of households’ welfare is made in this article. On the basis of received conclusions social policy areas directed at preserving or enhancing the welfare are defined.


2019 ◽  
Vol 98 (4) ◽  
pp. 167-173

Introduction: Alveolar echinococcosis (AE) is a zoonosis caused by Echinococcus multilocularis. AE is primarily localised in the liver. Echinococcus multilocularis imitates tumour-like behaviour. It can metastasise through blood or lymphatic system to distant organs. Echinococcosis often remains asymptomatic due to its long incubation period and indistinct symptoms. Clinical symptoms are determined by the parasite’s location. Diagnosis of echinococcosis is based on medical history, clinical symptoms, laboratory tests, serology results, imaging methods and final histology findings. Surgical removal of the cyst with a safety margin, followed by chemotherapy is the therapeutic method of choice. Case report: We present a case report of alveolar echinococcosis in a thirty-year-old female patient in whom we surgically removed multiple liver foci of alveolar echinococcosis. The disease recurred after two years and required another surgical intervention. Conclusions: Alveolar echinococcosis is a disease with a high potential for a complete cure provided that it is diagnosed early and that the recommended therapeutic procedures are strictly adhered to.


1986 ◽  
Vol 18 (4-5) ◽  
pp. 233-244 ◽  
Author(s):  
J. E. Portmann ◽  
R. Lloyd

For centuries the sea has absorbed a variety of inputs from rivers, streams, salt marshes and the atmosphere. It is generally accepted that additional limited inputs by man are unlikely to have a significant effect on the marine environment. Various control systems have been constructed to provide a framework within which the regulation of anthropogenic inputs can be achieved. These are briefly reviewed. With care, and in the light of past experience in both freshwater and marine environments, reasonable assumptions or estimations can be applied where uncertainties exist; safe limits can therefore be set for discharges. Case histories are used to illustrate the contention that it is possible to assess the assimilative capacity of a marine area to receive wastes. There is a major distinction to be drawn between contamination and pollution of the marine environment. Moreover, acknowledgement of the assimilative capacity concept in the marine environment does not automatically provide dischargers with the right to utilise that capacity either in part or to the upper limit. What it does is indicate the upper limit which must not be exceeded if pollution is to be avoided, and provide an indication to the control authority of the safety margin involved in the discharge limits they set accordingly.


2014 ◽  
Author(s):  
Curtis L Smith ◽  
Zhegang Ma ◽  
Tom Riley ◽  
Diego Mandelli ◽  
Joseph W Nielsen ◽  
...  

Author(s):  
Maryam Muhammad Mailafiya ◽  
Mohamad Aris Mohd Moklas ◽  
Kabeer Abubakar ◽  
Abubakar Danmaigoro ◽  
Samaila Musa Chiroma ◽  
...  

Background: Cockle shell-derived calcium carbonate nanoparticles (CSCaCO3NP) are natural biogenic inorganic material that is used in drug delivery mainly as a bone-remodeling agent as well as a delivery agent for various therapeutics against bone diseases. Curcumin possess wide safety margin and yet puzzled with the problem of poor bioavailability due to insolubility. Propounding in vitro and in vivo studies on toxicity assessments of newly synthesized nanoparticles are ongoing to overcome some crucial challenges regarding their safety administration. Nanotoxicology has paved ways for concise test protocols to monitor sequential events with regards to possible toxicity of newly synthesized nanomaterials. The development of nanoparticle with no or less toxic effect has gained tremendous attentions. Objective: This study aimed at evaluating the in vitro cytotoxic effect of curcumin-loaded cockle shell-derived calcium carbonate nanoparticles (Cur-CSCaCO3NP) and assessing its biocompatibility on normal cells using standard techniques of WST’s assay. Method: Standard techniques of WST’s assay was used for the evaluation of the biocompatibility and cytotoxicity. Result: The result showed that CSCaCO3NP and Cur-CSCaCO3NP possess minimal toxicity and high biocompatibility on normal cells even at higher dose of 500 µg/ml and 40 µg/ml respectively. Conclusion: CSCaCO3NP can be termed an excellent non-toxic nanocarrier for curcumin delivery. Hence, curcumin loaded cockle shell derived calcium carbonate nanoparticles (Cur-CSCaCO3NP) could further be assessed for various in vivo and in vitro therapeutic applications against various bone related ailments.


2000 ◽  
Vol 33 (13) ◽  
pp. 4836-4841 ◽  
Author(s):  
P. Adriaensens ◽  
L. Storme ◽  
R. Carleer ◽  
D. Vanderzande ◽  
J. Gelan ◽  
...  

2008 ◽  
Vol 2008 ◽  
pp. 1-9 ◽  
Author(s):  
Enrico Zio ◽  
Francesco Di Maio

In the present work, the uncertainties affecting the safety margins estimated from thermal-hydraulic code calculations are captured quantitatively by resorting to the order statistics and the bootstrap technique. The proposed framework of analysis is applied to the estimation of the safety margin, with its confidence interval, of the maximum fuel cladding temperature reached during a complete group distribution blockage scenario in a RBMK-1500 nuclear reactor.


Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 816
Author(s):  
Danijela Markovic ◽  
Jörg Freyhof ◽  
Oskar Kärcher

Thermal response curves that depict the probability of occurrence along a thermal gradient are used to derive various species’ thermal properties and abilities to cope with warming. However, different thermal responses can be expected for different portions of a species range. We focus on differences in thermal response curves (TRCs) and thermal niche requirements for four freshwater fishes (Coregonus sardinella, Pungitius pungitius, Rutilus rutilus, Salvelinus alpinus) native to Europe at (1) the global and (2) European continental scale. European ranges captured only a portion of the global thermal range with major differences in the minimum (Tmin), maximum (Tmax) and average temperature (Tav) of the respective distributions. Further investigations of the model-derived preferred temperature (Tpref), warming tolerance (WT = Tmax − Tpref), safety margin (SM = Tpref − Tav) and the future climatic impact showed substantially differing results. All considered thermal properties either were under- or overestimated at the European level. Our results highlight that, although continental analyses have an impressive spatial extent, they might deliver misleading estimates of species thermal niches and future climate change impacts, if they do not cover the full species ranges. Studies and management actions should therefore favor whole global range distribution data for analyzing species responses to environmental gradients.


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