The Stirling Engine Essay Example For Students

The Stirling Engine Essay The Stirling EngineRobert Stirling invented the Stirlingengine in 1816. At the time he was a Scottish minister. Stirling engineswere the safest engines made during that time period that would not explodelike a steam engine could. The Stirling engine would not explode becausethe pressures could not be elevated to that to such a high level. The machinesimply stopped when the heater section failed from thermal stress or imperfectionsin the material or manufacturing process. So from that day on there wasa better, safer way to produce power, far superior than that of a steamengine. A Stirling Engine is a mechanical device,which operates on a closed looping thermodynamic cycle. Different temperaturelevels cause compression and expansion of the air or steam, which causesthe piston arms to move back and forth keeping up with the changes in theinternal pressure. The flow of the steam is controlled by changes in thevolume of the hot and cold spaces, without the use of valves. The Stirling cycle can be is still appliedto day in common appliances such as a refrigerator. The heat cycle whenapplied to a heat cycle can produce cool air. This will occur when workis done on the Stirling device, and the heat energy is discarded into theroom. The heat energy that came from the Stirling cycle would be take fromthe inside of the refrigerator therefore making it cooler on the inside. We will write a custom essay on The Stirling Engine specifically for you for only $16.38 $13.9/page Order now In 1876 Rev. Stirling wrote in a letterabout his brother James, who had just died, These imperfections havebeen in great measure removed by time and especially by the genius of thedistinguished Bessemer. If Bessemer iron or steel had been known thirtyfive or forty years ago there is scarce a doubt that the air engine wouldhave been a great successIt remains for some skilled and ambitious mechanistin a future age to repeat it under favorable circumstances and with completesuccess. Rev. Dr. Robert Stirling (1790-1878) from Stirling Enginesby G. Walker. Robert Stirling applied for his first patentsfor this engine and the economizer in 1816, only after a few months ofgetting nominated as a minister at the Church of Scotland. Sir George Caleyhad devised air engines previous to this time and other devices calledair engines were known as early as 1699. Steam engines began to carry abad name along with it because they were so dangerous. Air engines wereso safe and they operated on completely different principles. Theeconomizer or regenerator has come to be recognized as a most importantpart of the patent that Robert Stirling received. This patent was so outstandingbecause of the fact that it predated much of the study of thermodynamics. Some historians believe that the reason for Robert Stirlings efforts atsuch a device were driven by his concern for the working people of hisparishes as steam engines were being used extensively in that area andtime period. Because of the lack of strength in the materials availableto construct, they would frequently explode sending shrapnel, boiling water,and steam at the people working nearby. After the years the gasoline internalcombustion engine has taken over. The reason this occurred was becauseof the time it takes for a Stirling engine to heat up enough to get moving. Lately with all of the problems with the environment a need for automobileengines with low emission of toxic gases has revived interest in the Stirlingengine. Some Stirling engines have been built with up to 500 horsepowerand with efficiencies of 30 to 45 percent. The common internal-combustionengine would have efficiency in the range of 20 to 25 percent. .ua0b66b88758c6a93583f312852cda66d , .ua0b66b88758c6a93583f312852cda66d .postImageUrl , .ua0b66b88758c6a93583f312852cda66d .centered-text-area { min-height: 80px; position: relative; } .ua0b66b88758c6a93583f312852cda66d , .ua0b66b88758c6a93583f312852cda66d:hover , .ua0b66b88758c6a93583f312852cda66d:visited , .ua0b66b88758c6a93583f312852cda66d:active { border:0!important; } .ua0b66b88758c6a93583f312852cda66d .clearfix:after { content: ""; display: table; clear: both; } .ua0b66b88758c6a93583f312852cda66d { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .ua0b66b88758c6a93583f312852cda66d:active , .ua0b66b88758c6a93583f312852cda66d:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .ua0b66b88758c6a93583f312852cda66d .centered-text-area { width: 100%; position: relative ; } .ua0b66b88758c6a93583f312852cda66d .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .ua0b66b88758c6a93583f312852cda66d .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .ua0b66b88758c6a93583f312852cda66d .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .ua0b66b88758c6a93583f312852cda66d:hover .ctaButton { background-color: #34495E!important; } .ua0b66b88758c6a93583f312852cda66d .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .ua0b66b88758c6a93583f312852cda66d .ua0b66b88758c6a93583f312852cda66d-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .ua0b66b88758c6a93583f312852cda66d:after { content: ""; display: block; clear: both; } READ: Kfc Vision Mission And Principles Worldwide EssayOne of the fastest moving technologiesis that of composites. These materials have a type of plastic make up alongwith other properties. The strength of this type of material is superiorin nature and for the purposes of a Sterling engine, I feel that it wouldbe perfectly suited. They have already begun to experimentally replacecertain motor parts in the internal combustion engine, such as the pistons. The advantages of this would be that the weight of internal parts wouldbe significantly lighter and therefore able to run at higher speeds. Anotheradvantage would be that the heat developed inside the engine would haveless affect on the components because composites react, (shrink and expand)less that a metal would. Lubrication also plays a huge part in engineperformance. If all parts slide together easy than the total force putinto overcoming friction would be reduced. Bearings and other parts wouldalso play a large part in reducing friction. The design technology of sterling enginesover the years has changed very slowly. Over the years the materials haveslowly began to change, what was once a wood wheel is now machined outof steal. The main theory of the Sterling cycle has remained the same,but because of its incapability to be convenient when placed into a car,the Sterling engine has never become a huge success. This probably explainswhy the manufacturing process has never moved into a mass production orand assembly line operation of larger sized engines. The model industrythat produces them, as toy is probable the only type of company that doesmass-produce them. Because the parts for the Stirling engine are fairlyeasy to machine, the materials are common, and fairly inexpensive, an assemblyline type of production would be fairly easy and inexpensive to set up. These are the 2 basic design types; thetwo-piston type Stirling engine is shown to the left. A space above a hotpiston is always heated and the space above a cold piston is always cooled. The displacer type Stirling engine (the one to the right) has a space abovea displacer piston, and it is always heated by a heat source. A space belowthe displacer piston is cooled always. The displacer piston displaces hotair and cold air. The 1900s brought on a time of industrializationand few things were still made by hand. In this age Stirling engines couldbe built bye assembly lines but Henry Ford had already began productionof his model T Ford, which used an internal combustion engine. This prettymuch killed the need for the Stirling engine. During this these old timesprototypes were almost non-existent except for that of a seldom made model. The reason this occurred is if a prototype was made it was probably putinto use not just set aside whit the actual models were getting manufactured. Before this time if somebody wanted something they had to build it forhim or her self, or they would have to find someone to build it for them. This explains why there were very few Sterling engines that were similarback then. Most parts were built by hand which explains the wooden flywheel. Because the cost of the part presently used to make it are so cheep andthe parts are adequate to the demands of this engine. If I was the designer of the Stirlingengine and I had the technology of today to help me in my work I wouldhave to make it out of composite products or at least a good portion ofit. The Sterling engine in itself if very safe and the simple facts thata cleaner fuel that is being burned will also reduce emissions making ita better engine for the environment. To increase power and make it runfaster I would add piston rings to the piston to give it a tighter seal. .ub26986fbbc2521269317cb0aa9fb5a6c , .ub26986fbbc2521269317cb0aa9fb5a6c .postImageUrl , .ub26986fbbc2521269317cb0aa9fb5a6c .centered-text-area { min-height: 80px; position: relative; } .ub26986fbbc2521269317cb0aa9fb5a6c , .ub26986fbbc2521269317cb0aa9fb5a6c:hover , .ub26986fbbc2521269317cb0aa9fb5a6c:visited , .ub26986fbbc2521269317cb0aa9fb5a6c:active { border:0!important; } .ub26986fbbc2521269317cb0aa9fb5a6c .clearfix:after { content: ""; display: table; clear: both; } .ub26986fbbc2521269317cb0aa9fb5a6c { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .ub26986fbbc2521269317cb0aa9fb5a6c:active , .ub26986fbbc2521269317cb0aa9fb5a6c:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .ub26986fbbc2521269317cb0aa9fb5a6c .centered-text-area { width: 100%; position: relative ; } .ub26986fbbc2521269317cb0aa9fb5a6c .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .ub26986fbbc2521269317cb0aa9fb5a6c .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .ub26986fbbc2521269317cb0aa9fb5a6c .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .ub26986fbbc2521269317cb0aa9fb5a6c:hover .ctaButton { background-color: #34495E!important; } .ub26986fbbc2521269317cb0aa9fb5a6c .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .ub26986fbbc2521269317cb0aa9fb5a6c .ub26986fbbc2521269317cb0aa9fb5a6c-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .ub26986fbbc2521269317cb0aa9fb5a6c:after { content: ""; display: block; clear: both; } READ: Purchasing A Small Business EssayTo reduce friction in the flywheel I would make sure bearings were placeron the axle and make sure they were oiled properly. Another was to makethe engine move faster would be to add some wings or flattened metal sheetsto the cool piston case in order to increase surface area allowing it tocool even faster.

Occupational Therapists essays

Occupational Therapists essays An occupational therapist work with individuals who have conditions that are mentally, physically, developmentally, or emotionally disabling, and help them to develop, recover, or maintain daily living and working skills. Their goal is to help their clients have independent, productive, and satisfying lives. They use resources such as computers, and do physical activities with them, such as, teaching them how to dress, cook, and eat. They also use physical strength to help them build their strength and dexterity. Another thing they do is teach them life skills, such as, decision making, abstract reasoning, problem solving, and perceptual skills. Occupational therapists also go to such lengths as designing or making special equipment to aid their clients. Along with this, they must keep accurate records for evaluating clients, billing, and reporting to physicians and others. An average workweek is about 40 working hours, however, about 1/3 of all occupational therapists work part time. Many work in spacious rooms with medical equipment, but fatigue can become a big factor. Another negative aspect is that they can strain the bodies, especially their back, and may spend many hours in a car per day. They may hire assistants, but this may become costly. In 1996, occupational therapists held about 57,000 jobs. Most of these jobs were in hospitals, but there were also jobs in rehabilitation centers and pediatric hospitals. Others work in private practices or become solo practitioners. They obtain their clients by being referred to by physicians or other health care professionals. A bachelors degree in occupational therapy is a minimal requirement to obtain this position, but to gain a license one must pass a national certification exam. All of the U.S., Puerto Rico, and Washington D.C. regulate occupational therapy. Along with a bachelors degree, a masters is also obtainable. Along with the education, on must also com...

US. Energy Policy Essay Example | Topics and Well Written Essays - 1000 words

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COMMUNITY PROFILE Essay Example | Topics and Well Written Essays - 2000 words

COMMUNITY PROFILE - Essay Example This paper delves into one specific region that has been put on the spot for the threat the people are facing, especially when it comes to the aspect of physical inactivity. It also strives to bring out some of the factors that influence different characteristics of members of this population, and how their health status might be affected due to some of the mentioned factors. Factors that influence their health will also be mentioned, giving rise to the morbidity factors, and the risks to which most of them are exposed. The aim of this paper is to examine some of the behavioral traits that exist in this population, and why the proportion of adults in the region participating in physical activity is low. In so doing, it may be possible to identify factors that may improve these numbers. The population that is under study is London Borough of Hillingdon, where it is believed that the average proportion of individuals who participate in physical activity is less than the average of England. This region is of interest because it is said to be among the greenest cities in the world. This is amazing considering the statistics that show of the inactivity levels displayed in relation to the individuals in this society (DH 2012). One might be forced to think that living in such an environment would make people choose a healthier lifestyle, but studies indicate otherwise. Adults and children are not spending an average of 3 hours a week on physical activity, which should be a cause for alarm. Children alone, on average, should have at least 60 minutes per day of physical activities that help prevent some of the health problems that may arise (Long et al. 2009). Current statistics indicate that at least one in six deaths occurs as a result of physical inactivity, and this ma kes this issue as immense as smoking. It is also interesting to note that this

International Relations paper Essay Example | Topics and Well Written Essays - 2000 words

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Viable But Non Culturable Bacteria Biology Essay

Viable But Non Culturable Bacteria Biology Essay Viable but Non-Culturable state is a unique survival strategy of many bacteria in environment in response to adverse environmental conditions. VBNC bacteria cant be cultured on routine microbiological media but they remain viable and retain their virulent capacity too. VBNC bacteria can be resuscitated when provided with appropriate conditions. A good number of bacteria including many human pathogens have been reported to enter VBNC state. Though, there was disputes on the existence of VBNC in past, extensive molecular studies have resolved most of them and VBNC has been accepted as distinct survival state by all. VBNC bacteria are considered as threats to public health and food safety due to their non-detectability and virulence as food and water have been reported to be contaminated with pathogens at VBNC state though conventional methods declared them as safe and clean. A number of outbreaks have also been reported where VBNC bacteria has been implicated as causative agent. Furthe r molecular and combinatorial research in conjunction with predictive modeling are needed to elucidate the mechanisms and to identify the critical points to tackle the threat posed by VBNC bacteria with regard to public health and food safety. Key words: VBNC, Pathogen, public health, Food safety, Detection Introduction The cells that form colony in specific media are the culturable cells. Viable means metabolically or physiologically active. So the cells those are metabolically or physiologically active but cant be cultured on specific media are the viable but non-culturable cells (VBNC) (Bogosian Bourneuf, 2001). Most microorganisms growing in nature have yet to be cultured in the laboratory. In fact less than 1% of the microorganisms in natural water and soil samples are cultured in viable count procedures (Barcian Arana, 2009). In 1982, Prof. Rita Colwell and co-workers introduced the term Viable But Non-Culturable Bacterial Cells (VBNC) to distinguish particular cells that could not form colonies on solid media but obtained metabolic activity and the ability to elongate after the administration of nutrients (Xu et al., 1982). According to Oliver (1995), VBNC can be defined as a metabolically active bacterial cell that crossed a threshold in this way, for known or unknown reasons and become unable to multiply in or on a medium normally supporting its growth. Most of the bacteria that enter VBNC state are gram negative species belonging to the gamma subclass of the Proteobacteria branch, except for Rhizobium, Agrobacterium and Helicobacter-Campylobacter species (Oliver, 2000). History Debra Bashford and colleagues announced that they had recovered Vibrio cholerae from streams and drainage ditches, including sites with negligible chance of sewage contamination. Around the same lime, Rita Colwell was also finding Vibrio cholerae in Maryland. She and her coworkers showed that both this bacterium and E. coli, incubated in artificial sea water remained viable but lost the capacity to form colonies on culture media (Colwell Grimes, 2000). Soon Salmonella enteritidis, Shigella sonnie and Legionella pneumophila joined the list of organisms known to be capable of entering a state in which they failed to show up on nutrient agar yet took up substrates and signaled in other ways that they were certainly not dead. The use of laboratory media to recover and enumerate bacteria and lo link them with or absolve them from pathological and other activities became obsolete by the new discoveries and a term VBNC (viable but non-culturable) came (McDougald et al., 1998). VBNC Microorganisms that do not grow in culture methods, but which are still metabolically active and capable of causing infections in animals and plants are said to be in VBNC state. The conditions for these organisms to resume growth are not being met using the normal laboratory culture conditions (Yamamoto, 2000). Bacteria that have been semi-starved will immediately resume growth when provided with the appropriate nutrients and conditions. Viable but non-culturable cells will not resume growth even when nutrients are provided (NystrÃÆ'-m, 2001). VBNC cells exhibit active metabolism in the form of respiration or fermentation, incorporate radioactive substrates, and have active protein synthesis but cannot be cultured or grown on conventional laboratory media. They have been detected by observing discrepancies between plate count enumeration of bacterial population and direct staining and microscopic counts (Sachidanandham Gin, 2009). These cells may be of particular problems in the e nvironment if they are pathogens, for example, viable but non-culturable cells of Vibrio cholerae, Enteropathogenic E. coli, Legionella pneumophila and various other bacteria have been shown to regain culturability after they have entered the intestinal tracts of animals (Colwell et al., 1996). The VBNC state is defined as a state of dormancy triggered by environmental harsh conditions, such as nutrient starvation (Cook Bolster, 2007), temperature (Besnard et al., 2002), osmotic stress (Asakura et al., 2008), oxygen availability (Kana et al., 2008), several food preservatives (Quirà ³s et al., 2009), heavy metals (Ghezzi Steck, 1999), exposure to white light (Gourmelon et al., 1994) and decontaminating processes, as pasteurization of milk (Gunasekera et al., 2002) and chlorination of wastewater (Oliver, 2005). VBNC state is believed to be a unique survival strategy of bacteria in response to environmental stresses (Oliver, 2010). It is also considered as an important reservoir of many human pathogens in the environment (Lleo et al., 2007). VBNC state has been a matter of dispute for ling since its inception, due to the difficulty of differentiation of VBNC cells dormant cells through resuscitation phenotypic studies, recent molecular studies, data of which supported the existence of VBNC state, the dispute has mostly been put to rest (Barer and Harwood, 1999). VBNC Pathogens Following list includes but not limited to pathogenic bacteria that can enter VBNC state (Oliver, 2010)- Aeromonas hydrophila, Agrobacterium tumefaciens, Burkholderia cepacia, Campylobacter jejuni, Enterobacter aerogenes, Enterobacter cloacae, Enterococcus faecalis, Escherichia coli (including EHEC), Helicobacter pylori, Klebsiella pneumoniae, Legionella pneumophila, Listeria monocytogenes, Mycobacterium tuberculosis, Pseudomonas aeruginosa, Salmonella typhi, Salmonella typhimurium, Shigella dysenteriae, Shigella flexneri, Shigella sonnei, Streptococcus faecalis, Vibrio alginolyticus, Vibrio cholerae, Vibrio harveyi, Vibrio parahaemolyticus, Vibrio vulnificus (types 1 and 2) Characteristics of Bacteria in VBNC state 1. Maintain apparent cell integrity; 2. possession of some form of measurable cellular activity (Lai et al., 2009); 3. possess apparent capacity to regain culturability (Anuchin et al., 2009); 4. respond to external stimulus by specific gene expression (kell et al., 1998); 5. low metabolic activity (oliver, 2005); 6. Exhibit dwarfing (Costa et al., 1999); 7. reduced nutrient transport; 8. High ATP level and high membrane potential (Signoretto et al., 2000); 9. extensive modifications in cytoplasmic membrane fatty acid compositions (Day Oliver, 2004); 10. Changes in cell wall peptidoglycan such as increasing cross linking, increasing muropeptides bearing covalently bound lipoprotein shortening of average length of glycan strands (signoretto et al., 2002); 11. Higher autolytic capability than exponentially growing cells; 12. Plasmids are retained; 13. changed antibiotic sensitivity as metabolic activity is lower, most bacteria at VBNC state demonstrate high antibiotic resistance (Ol iver, 2010); 14. Changes in outer-membrane protein profile (Muela et al., 2008); 15. Continuous gene expression (Maalej et al., 2004) etc. Conditions stimulating VBNC state In the environment, bacterial cells can enter VBNC state may be due to- 1. Lack of nutrients; 2. Lack of temperatures; 3. High pressure; 4. Sharp changes in pH or salinity (Cunningham et al., 2009); 5.damage to or lack of an essential cellular component; 6. DNA damage; 7. activation of lysogenic phages or suicide genes such as sok/hak or autolysins (Aizenman et al., 1996); 8. Nutrient starvation; 9. incubation outside the normal temperature range of growth; 10. elevated or lower osmotic concentrations; 11. oxygen concentrations (Mascher et al., 2000); 12. food preservatives; 13. Heavy metals (Del Campo et al., 2009); 14. exposure to white light; 15. pasteurization of milk (Gunasekara et al., 2002); 16. chlorination of wastewater (Oliver, 2005) etc. Public health significance of VBNC Though virulence of bacteria in VBNC state is still not very clear, many believed that pathogens in VBNC state are unable to induce infection/disease but still retain their virulent properties has potential to cause disease infection following resuscitation and resume of active metabolic state, which occurs when they pass through host animal (Baffone et al., 2003). The VBNC state appears to be the common to many bacteria especially those which have aquatic habitats, and may represent a mechanism to survive adverse environmental factors as temperature, salinity etc. or have a means of inducing cross protection against other adverse factors (Du et al., 2007). Among these bacteria entering this state are many significant human pathogens and indicator bacteria of these pathogens; such cells may represent a public health hazard and may be a factor in human health and/or disease (Rivers Steck, 2001). Even today, it is still not possible to cultivate most bacterial species directly from the environmental samples or after exposure of previously culturable cells to environmental conditions unfavorable for growth and multiplication in vitro. The passage of VBNC through an appropriate animal host will induce return of culturability. Even these VBNC bacteria retain their pathogenicity and may trigger life in vivo and thus cause severe disease (Sardessai, 2005). Under normal condition it is not possible to culture or detect VBNC. Many diagnostic laboratory set up does not have sufficient molecular facilities to detect VBNC. In case of food and water quality control test, such VBNC may not be detected. Even some indicator of some pathogenic bacteria undergoes VBNC state and may remain undetected (Signoretto et al., 2004). Upon consuming such food or after drinking such water, one may be infected by those VBNC that can trigger life as well as pathogenicity (Adams et al., 2003). Thus, environmental and clinical samples no longer can be considered free from pathogens if culturing yields negative results. For the general public, the presence of VBNC in water and food may be related to low-grade infections or so called aseptic infection. For example, Vibrio cholerae O1 in the surface water remain as non-culturable state. These water sources are used for domestic purpose regularly and posed a risk of infection (Edwards, 2000). When conditions are not favorable for growth then it transforms to the non-culturable state in association with crustacean copepods. Persistence of Vibrio cholerae in water in the VBNC state is an important public health factor, since detection will not be successful if only conventional cultural methods are used (Barer et al., 1993). Similarly, Shigella can undergo VBNC state in water but become a threat when enter in human body. Thus it is important to recognize that non-culturable bacteria are capable of producing diseases. The first evidence of pathogenicity of non-culturable cells was the demonstration of fluid accumulation in rabbit ileal loop assay (RICA) by VBNC Vibrio cholerae O1, followed by human volunteer experiments (Amel et al., 2008). VBNC E. coli non-culturable cells were re-isolated after passage through rabbit ileal loops 4 days post inoculation and chick embryos died when injected with non-culturable cells of Legionella pneumophila, led to the conclusion that VBNC pathogens remain potentially pathogenic. So, VBNC has a huge significance in public health care (Cappelier et al., 2007). Reports indicate that many potentially harmful bacteria survive treatment and persist in processed food, pasteurized milk, potable water and in the environment (Colwell et al., 2000). Many evidences suggested that recurrent urinary tract infections in many individuals are caused by uropathogenic E. coli cells which remain in VBNC state (Anderson et al., 2004) thus resistant to antibiotic treatment cause reinfection when resuscitate back to active metabolic state (Steck, 2001; Mulvey et al., 2001). Studies also showed that uropathogenic E. coli retain enteropathogenicity at VBNC state through continued production of enterotoxin (Pommepuy et al., 1996). Nilsson et al. (2002) showed that VBNC Helicobacter pylori cells can express virulence factors such as cagA, vacA and vreA. All these above evidence proved that many deathly pathogenic strains not only enter but also persist survive in VBNC state in environment most of them remain infectious as well. VBNC state of foodborne bacteria- a challenge in food safety Many evidences suggested presence of VBNC bacteria in food (Ordax et al., 2009). For example, in stored wine, acetic acid and lactic acid bacteria entered VBNC state as consequence of lack of oxygen and presence of sulphites, respectfully (Millet and Lonvaud-Funel, 2000). Food and its surrounding environment is a complex system, in which physic-chemical characterisitcs (pH, aw, chemical composition) and environmental factors (storage temperature and time, decontamination treatments, packaging under modified atmosphere) act simultaneously on contaminating bacteria (Sun et al., 2008). For example, it has been demonstrated that refrigerated pasteurized grapefruit juice induced VBNC state in E. coli O157:H7 and S. typhimurium within 24 hours of incubation (Nicolo et al., 2011). Again, Gunasekera et al. (2002) reported that in pasteurized milk which have undergone thermal treatment, contaminating bacteria such as E. coli and Pseudomonas putida enter into VBNC state but retained transcription and translation machineries. Several foodborne outbreaks has been reported in Japan, where pathogen such as Salmonella enterica subsp. enterica (Asakura et al., 2002) and E. coli O157 (Makino et al., 2000) in food in VBNC state were responsible for the outbreak. Therefore, the role of food and treatment for food preservation in induction of VBNC state has to be elucidated. Predicitve models offered by biomathematics and bioinformatics would be very helpful tools, in order to evaluate the possibility that, under certain conditions, pathogen bacteria contaminating a tipology of food may enter the VBNC state (Fakruddin et al., 2012). Methods of detection of VBNC bacteria 1. Bright Field Microscopy with Nalidixic acid For detection of Bright-field or light microscopic is usually used. Cell division inhibitor such as nalidixic acid (20-40 mg/L) is used to stop cell division. After such treatment the viable cells, which actively growing, will be appeared as lengthen and the non-viable/ metabolically inactive cell will remain as it is. The cells are then observed under microscope. Viable cells will be seen as elongated whereas VBNC/ dormant cells will be seen as oval and large. 2. Fluorescent Microscopy Various fluorescent staining procedures are used in combination with other procedure to determine VBNC organisms. Frequently used stains are Acridine orange, 4,6- Diamino-2-phenyl indole (DAPI), Fluorescein isothiocyanante (FITC), Indophenyl-nitrophenyl-phenyl tetrazolium chloride (INT), 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) etc (Villarino et al., 2000). Table: Fluorescent dyes used for detection of VBNC bacteria Dye Mechanism Reaction Acridine orange Acridine orange stain cells depending on the ratio of DNA to protein in the cells Actively reproducing cells appear green but slow-grower or non-reproducing cells at time of staining appear orange Di-amino-phenyl-indole (DAPI) Living cells look green under fluorescent microscope Indophenyl-nitrophenyl-phenyl tetrazolium chloride (INT) INT deposit red dye in cells that have active dehydrogenase and thus determine which of the observed cells are metabolically active INT react with dehydrogenase enzyme to produce formazone and red color, thus living cells appear red. Nalidixic acid (NA) Lengthen metabolically active cells, VBNC cells remain as it is Cells that are dividing appear to be longer in size than VBNC Fluorescein isothiocyanante (FITC) Enzyme activity in living cell FITC stain living cells violet or blue In recent years, a new differential staining assay, the BacLight ® Live/Dead assay, has been developed. The assay allows to simultaneously count total and viable (metabolically active) cells, by using two nucleic acid stains, that is green-fluorescent SYTO ® 9 stain and red-fluorescent propidium iodide stain. These stains differ in their ability to penetrate intact cell membranes. When used alone, SYTO ® 9 stain labels both live and dead bacteria. In contrast, propidium iodide penetrates only bacteria with damaged membranes, reducing SYTO ® 9 fluorescence when both dyes are present. Thus, live bacteria with intact membranes fluoresce green, while dead bacteria with damaged membranes fluoresce red (Rowan, 2011). 3. Gene probe / oligonucleotide probe / hybridization: Molecular analysis can also be used to study non-culturable microorganisms in nature. Oligonucleotide probes of l8-20 nucleotides are proving most useful because they hybridize rapidly to specific DNA sequences of target organisms. These gene probes can reveal closely related organisms or organisms with similar functional capabilities. Especially useful for the analyses of rRNA that demonstrate the presence of diverse microbial populations whose phylogenetic relationships can be ascertained by comparison with rRNA sequences from previously described microorganisms (Josephson et al., 1993). Blotting: There are different types of blotting such as colony blot, slot blot, dot blot and southern blot. The principle of blotting is the use of radio- or non-radioactive or fluorescence labeled probe (DNA/RNA/Antibody) to detect VBNC cells directly from the environmental samples. Fluorescent in situ Hybridization (FISH): In situ hybridization is an alternative format for hybridization probes in which fluorescence labeled DNA or RNA probes are hybridized with target nucleic acids in whole, permeabilized cells. The application of this method to the detection of single microbial cells by using rRNA-targeted probes in combination with epifluorescent microscopy has been developed. This is done through selective targeting of regions of rRNA, which consist of conserved and variable nucleotide regions. By choosing the appropriate rRNA probe sequence, FISH can be used to detect all bacterial cells (a universal probe) or a single population of cells (a strain specific probe) of VBNC. It has lower sensitivity and cannot distinguish live and dead cells. 4. Molecular techniques: Hybridization probes and DNA/RNA amplification: Hybridization probes are nucleic acids (DNA/RNA) which have been (a) chemically or radioactively labeled and are used to detect complementary target DNA/RNA. Hybridization assay DNA/ RNA probes form a stable double stranded structure with target nucleic acid via H-bonding between complementary bases. Amplification of targets: DNA Based methods: Specific amplification of DNA targets in bulk DNA extracts from environmental and clinical samples permits detection of specific organisms or groups of related organisms without the need to cultivate them. DNA recovery procedures do not discriminate between culturable and non-culturable forms of the target organisms- all cells with intact amplification targets will be detected. Confocal laser microscopy in combination with fluorescence-based hybridization assays, also provide a more sensitive method for detecting and identifying VBNC organisms. RNA based methods: Due to the failure of distinguishing between dead or live cells by DNA-based methods, the mRNA level may be a valuable estimate of gene expression and/or cell viability under different conditions (Lleo et al., 2000). RT-PCR: RT-PCR (Reverse Transcriptase PCR) can distinguish between Live and dead cell. This is possible because this is an mRNA based method and mRNA is short lived (half-life less than 1 minute), mRNA is only present in metabolically active cells, not found in nature after the cell death. By this method we can study community relationship and can also detect non-culturable but active or live cells. DNase enzyme is used during the isolation of RNA from environmental samples. Reverse transcriptase and random primers are added to the reaction mixture and the RNA in the sample (both RNA and rRNA) is transcribed into DNA. PCR is then use to amplify the specific sequence of interest (Pai et al., 2000). Is the concept of VBNC is a misnomer? By extending the concept of bacterial self-suicide scientists tried to explain what happens when cells are exposed to chemical and physical injury (Forsman et al., 2000). Thus VBNC organisms came alongside with those, which do not grow in ordinary media but which do grow when offered selective or enrichment media. They said, Such cells are not un-culturable they wrote We are simply failing to provide appropriate conditions to support culture (Sinton, 2006). The reasons, which made the term, VBNC a misnomer are as follow: 1. Bacteria that have been semi-starved will immediately resume growth when provided with the appropriate nutrients and conditions. But viable but non-culturable bacteria do not resume growth when nutrients are provided. Evidence suggests that these cells have become too starved to be able to grow on rich medium initially; this phenomenon was observed over three decades ago and was known then as substrate accelerated death (Heim et al., 2002). It was found that substrate that normally supported growth of certain Gram-negative bacteria hastened their death when introduced into starved populations of these bacteria. These substrates were considered lethal substrates. These starved cells require an adjustment period to allow phenotypic adaptation back to the normal growth state (Epstein, 2009). A sudden shift to nutrient rich agar creates a metabolic imbalance that results in the formation of super-oxide and free radicals, causing DNA damage that can result in cell death (Barer Harwood , 1997). 2. There is yet no complete and perfect media to isolate arid culture all the organisms from environment. 3. Cells are usually-injured or stressed or starved condition in natural environment. So complete system has been devised to enrich or resuscitated the VBNC cells. Culture condition that can be applied in laboratory is not sufficient to recover all microorganisms i.e. yet it is not possible to provide or stimulate exact environmental conditions in the laboratory. Conclusion Regardless of the role that the VBNC state plays, it is clear that a large number of non-spore-forming bacteria, most notably a large number of human pathogens, are capable of entering this state, maintaining cellular structure and biology and continuing significant gene expression while otherwise non-culturable by standard laboratory methods. That they can exit from this state, and become culturable again, is also undeniable. Finally, it can no longer be questioned that the VBNC state plays a critical role in the survival of important human (and other) pathogens, and possibly in their ability to produce disease.

Antigone And Ismene Essay -- essays research papers

Antigone and Ismene The personalities of the two sisters; Antigone and Ismene, are as different from one another as tempered steel is from a ball of cotton. One is hard and resistant; the other: pliable, absorbing and soft. Antigone would have been a strong, successful 90's type woman with her liberated and strong attitude towards her femininity, while Ismene seems to be a more dependent 1950's style woman. Antigone acts as a free spirit, a defiant individual, while Ismene is content to recognize her own limitations and her inferiority of being a woman. In the Greek tragedy "Antigone", by Sophocles; Antigone learns that King Creon has refused to give a proper burial for the slain Polyneices, brother of Ismene and Antigone. Infuriated by this injustice, Antigone shares the tragic news with Ismene. From her first response, "No, I have heard nothing"(344). Ismene reveals her passivity and helplessness in the light of Creon's decree. Thus, from the start, Ismene is characterized as traditionally "feminine", a helpless woman that pays no mind to political affairs. Doubting the wisdom of her sisters plan to break the law and bury Polyneices, Ismene argues: We who are women should not contend with men; we who are weak are ruled by the stronger, so that &...

Analyse how national & local guidelines Essay

National legislation and guidance influence the development of local policies and procedures that affect every day work with children and young people. Policies must cover the protection of all children and young people under the age of 18 and the content of the policy must be reviewed annually. The LSCB (Local safeguarding children board) is responsible for ensuring that all agencies and departments that work with children and young people in the Borough, work in unity to support the welfare and safety of children in that area. To ensure that work is carried out in an effective manner the LSCB coordinate the work of local agencies to provide a more optimistic outcome in regards to children’s safeguarding. Red bridge works in line with the Every Child Matters program which states that each child has a right to: Be healthy Stay safe Enjoy and achieve Make a positive contribution Achieve economic well being Within childcare practice we must be aware that we have a clear and defined role in relation to child protection. Professionals working with children/young people i.e. teaching assistants, volunteers, outside agencies are DBS checked (Disclosure & barring service) previously known as CRB checks. Adults working with children should also be fully trained in safeguarding children by a nominated safeguarding adviser and have the opportunity to receive training in order to develop their understanding of the signs and indicators of abuse or neglect, this training is offered every 3 years. In order for child protection to work effectively we must ensure we have good inter relationships with other agencies and good cooperation from professionals that are competent in responding to child protection situations. If a child discloses information that concerns his/her welfare; we must make a record of exactly what the child has said in their words and report it to a safeguarding officer, ensuring that these records are kept confidentially and separated from pupils records. Guidance on confidentiality and sharing; the line manager/head teacher or safeguarding officer will only disclose personal information concerning a child to other members of staff on a need to know basis, however all staff must be aware that they have a responsibility to share information with other agencies. If a child or young person does disclose information to a member of staff and ask that that information remains ‘a secret’, it is vital that the member of staff tells the child/young person sensitively that they have a duty to transfer information to the appropriate agencies in order for other children to be safeguarded. Risk assessments are crucial to any setting and should be carried out regularly to ensure that there is no safeguarding threats to the children.

The Role of Management

The Role of Management Preface The subject of interest in this report is the responsibility of management in health and safety with reference to the UAE industries. United Arab Emirates (UAE) has expanded industrially and economically especially in the airline, construction, maritime, and petroleum sectors. Mass recruitment and utilization of laborers both high-skilled and low-skilled from developing countries has provided satisfaction to the manpower demands of these rapidly growing economic and industrial sectors. (Speegle, 2012)Advertising We will write a custom essay sample on The Role of Management specifically for you for only $16.05 $11/page Learn More This enormous recruitment has led to changes in population demographics. The total UAE population is approximately 8.2 million, with about 940,000 being Emiratis while the rest are multinational immigrant workers. These unique factors pose a number of challenges to the health and safety of workers. As a result, there is a hig h mortality rate. This paper purposes to illustrate the role management plays in reducing the risk of dangers associated with the UAE industries. It outlines and emphasizes the activities managers should carry out to minimize such risks. Safety is a crucial requisite in any industry. Every firm should establish a safety section in charge of all incidents and accidents. In addition, the report establishes the role of safety plans and health safety equipment programs in minimizing the risk of hazards in the UAE companies. This is to identify the missing links in management and poor managerial practices that give way to these hazards. The paper also tries to provide directions in the effort to minimize these problems. (Taylor, 2005) Introduction The UEA is a rapidly growing state both in population and economy. It consists of a federation of 7 emirates (Dubai, Abu Dhabi, Fujairah, Ajman, Sharjah, Ras Al Khaimah, and Umm al-Quwain). These are situated towards the southeast part of the A rabian Peninsula. Despite being a new state in the Middle East, UEA it has witnessed remarkable economic growth in the last 40 years, particularly in the airline, maritime, petroleum, and construction industries. Mass recruitment and utilization of laborers both high-skilled and low-skilled from developing countries has provided satisfaction to the manpower demands of these rapidly growing economic and industrial sectors. They possess varying academic qualifications, religious beliefs, work experience, native languages, and cultural practices. This mass employment has a tremendous effect on the population demographic patterns. Consequently, its population has increased largely since the year 1971. (Institute of Leadership Management, 2012)Advertising Looking for essay on business economics? Let's see if we can help you! Get your first paper with 15% OFF Learn More Problem description Occupational injuries as a cause of morbidity and mortality in UEA Injury is among the leading causes of mortality in the UAE cutting across all groups of people. Studies reveal that occupational associated deaths attributed to about 16% of all injury related fatalities in Abu Dhabi in the year 2007. Further, research studies suggest that the number of mortalities related to occupations injuries is rising. The 2007 Health Authority Abu Dhabi annual report reveals that 22% of all injuries are as a result of occupational injuries. Factors leading to increase in mortality rate due to occupational illness The rise of fatalities due to occupational injuries is alarming in the UAE industries. This has prompted the need to look into the underlying cause of these life threatening incidences. There are three major factors contributing to the rising number of work related deaths. These include:- 1. Lack of awareness of the occupational associated hazards e.g. Construction sites or chemical industries. 2. Inadequate training of the workers on the occupational hazard s and how to avoid them. 3. Poorly established safety measures in working areas as a result of poor management. (Lawrence B. Cahill, 2010) The role of management in minimizing risks associated with occupations For safety purposes, every industry should have a safety manager who ensures that all processes and operations work in an effective and safe manner. The safety manager also makes sure that all the staff members are conversant with the laid down operational regulations and safety rules of the company.Advertising We will write a custom essay sample on The Role of Management specifically for you for only $16.05 $11/page Learn More Operational role The safety manager is responsible for guiding the workers on the principles of safe operational procedures. In addition, they are also responsible for conducting investigations on the arising accidents and how to avoid them in the future. Supervisory responsibility The manager ensures that workers carry out all the operations and activities of a company in a manner that conforms to the Work safety-and Health administration rules and guidelines. The manager is the overall overseer of all activities in the industry. Risk assessment The manager should assess the type and frequency of occurrence of the risks associated with the workplace. This assists in projecting the amount of resources to be put in place for any cases that may arise. The manager may achieve this by identifying the most common hazards, identifying the people at risk, evaluating the common risks, and establishing ways of tackling them. (Taylor, 2005) Role of safety plans and health safety equipment programs Safety plans are crucial in ensuring a safe working environment hence reducing mortality cases. A safety plan is an outline of approaches prepared by the safety manager. It addresses the laid down recommendations on how to handle injuries and minimize risks causing them. A well-organized and planned safety plan helps in r educing fatalities resulting from occupational injuries. Safety equipment programs are responsible for ensuring that all the equipment used in an industry conforms to the standard safety and health specifications. They help reduce the number of accidents related to poor equipment. (Lawrence B. Cahill, 2010) Implementations The government of UAE has established laws and acts, and programs to promote safety in working areas. These help promote safety awareness in industries. They include: 1. The Federal Labor Law and AmendsAdvertising Looking for essay on business economics? Let's see if we can help you! Get your first paper with 15% OFF Learn More 2. The Height Aware Campaign 3. The Heat aware Campaign Conclusion Expatriate workers just like other employees; import their attitudes, beliefs, ideas, and experiences into the occupational areas. The incidence of occupational linked injuries in the UAE is alarming. Partly, it is due to recruitment of many expatriate workers for the rapidly developing industrial and construction projects. These have hence outpaced the capacity of health, labor, and education ministries to implement enough health and safety training and awareness programs. Safety and Health practitioners responsible for training of multinational workers should give special considerations to immigrant workers by developing a safety and health training and information program. (Speegle, 2012) This study was a quite a challenge as it encountered many shortcomings. Integrating information from all governmental departments and agencies dealing with safety management was quite involving. This report is simply an overview that needs further investigation. There is still need to research on this project since it is a leading crisis in UAE. Further studies should be conducted on how to minimize morbidity and mortality rates arising from the occupational injuries. Also, more research should be done to establish the best programs to be implemented. References Institute of Leadership Management, J. J. (2012). Managing Lawfully Health, Safety and Environment Super Series. Oxfordshire, London: Routledge. Lawrence B. Cahill, R. W. (2010). Environmental Health and Safety Audits. Lanham, Maryland: Government Institutes. Speegle, M. (2012). Safety, Health, and Environmental Concepts for the Process Industry. Clifton Park, New York: Cengage Learning. Taylor, B. (2005). Effective Environmental, Health, and Safety Management Using the Team Approach. Hoboken, New Jersey: John Wiley Sons.

Organic Chemistry Survival Tips

Organic Chemistry Survival Tips Organic chemistry is often considered the hardest chemistry class. Its not that its impossibly complicated, but there is a lot to absorb, in both the lab and classroom, plus you can expect to do some memorization to succeed at exam time. If youre taking o-chem, dont stress! Here are survival tips to help you learn the material and succeed in the class. 1) Choose How To Take Organic Chemistry Are you more of a mental sprinter or is distance running your style? Most school offer organic chemistry one of two ways. You can take the year-long course, broken into Organic I and Organic II. This is a good choice if you need time to digest and learn material or master lab protocols. Its a good choice if you tend to ask a lot of questions, because your instructor will be able to take the time to answer them. Your other option is to take organic over the summer. You get the whole shebang in 6-7 weeks, sometimes with a break in the middle and sometimes straight through, start to finish. If youre more of a cramming, run-to-the-finish type of student, this may be the way to go. You know your study style and level of self-discipline better than anyone else. Choose the learning method that works for you. 2) Make Organic Chemistry a Priority Your social life may take a hit while youre taking organic. It wont be your first chemistry class, so you already expect that. Try to avoid taking other challenging courses at the same time. There are only so many hours in the day to work problems, write lab reports, and study. If you load your schedule with sciences, youre going to get pressed for time. Plan to give time to organic. Set aside time to read the material, do the homework, and study. Youll also need some downtime to relax. Getting away from it for a while really helps the material click. Do not expect to just go to class and lab and call it a day. One of the biggest survival tips is to plan your time. (3) Review Before and After Class I know... I know... its a pain to review general chemistry before taking organic and to review notes before the next class. Reading the textbook? Agony. Yet, these steps truly help because they reinforce material. Also, when you review the subject, you may identify questions to ask at the beginning of class. Its important to understand each part of organic because topics build on those you have already mastered. Reviewing builds familiarity with the subject, which builds confidence. If you believe you can succeed at organic chemistry, you will. If youre scared of it, youll probably avoid it, which wont help you learn. After class not necessarily right away, but before the next class study! Review your notes, read, and work problems. (4) Understand, Dont Just Memorize There is some memorization in organic chemistry, but a large part of the class is understanding how reactions work, not just what structures look like. If you understand the why of a process, youll know how to approach new questions and problems. If you simply memorize information, youll suffer when its time for tests and you wont be able to apply the knowledge to other chemistry classes very well. (5) Work Lots of Problems Really, this is part of understanding. You need to work problems to understand how to solve unknown problems. Even if homework isnt picked up or graded, do it. If you dont have a firm grasp of how to solve problems, ask for help and then work more problems. (6) Dont Be Shy in Lab Learning techniques is an important part of organic chemistry. If you are unsure what to do, speak up. Ask lab partners, watch what other groups are doing, or find your instructor. Its okay to make mistakes, so dont beat yourself up if an experiment doesnt go as planned. Youre learning. Just try to learn from your mistakes and youll be fine. (7) Work With Others Any modern science career involves working as part of a team. Start honing your teamwork skills to survive organic chemistry. Study groups are helpful because different people may understand (and be able to explain) different concepts. Working together on assignments will probably get them completed more quickly. You may have gotten through general chemistry on your own, but theres no reason to go it alone in organic. Wondering why you should care about organic chemistry? Consider these examples of organic in everyday life. Learn Organic Chemistry Online

Simulation of low vision Essay Example | Topics and Well Written Essays - 1000 words

Simulation of low vision - Essay Example Visual performance may be affected. A person with low vision can use her reduced vision for learning about the world and for planning and doing tasks that need vision† (Low Vision, 2008). The IDEA Amendments of 1997 have yet another definition. They define children with visual impairment as those who have â€Å"visual impairments which even with correction, adversely effects†¦ educational performance.† 1. Generalization of skills: Many students with visual impairments may exhibit difficulty transferring skills acquired in one context to anther. It is important that instruction takes place in natural contexts and at appropriate times so the students internalizes meaning to the task. 2. Concrete versus abstracts learning: some students with visual impairments require hands-on learning experiences through their educational program in order to make sense of concepts and strategies for instructions that are more abstract. Often, the only way that students can learn new skills is through repetitive learning. For example, students who have visual impairments and exhibit cognitive delays may be taught a specific route to the cafeteria. Any change in route may confuse the student. 3. Attention span and distractibility: when initiating instructional programs for students who have visual impairments and other disabilities, the teacher must determine how long a student can attend to a specific task with and without supervision. Also, the environment is an influence on the student’s ability to stay on task and to maintain appropriate behavior. Many students with visual impairments are distracted by loud noises. Examples include the hum of fluorescent lights, a visually cultured classroom, and verbal communication by others in the same environment. They require auditory, tactical, or visual cues to anticipate the transition from one activity to the next. 4. Auditory versus visual learning: most students with visual impairments

The Key Drivers for Business Continuity Management Essay

The Key Drivers for Business Continuity Management - Essay Example 'Business Continuity can be seen as a bridge between Risk management and Emergency Planning; it utilizes the risk identification and management processes of formal risk management and the crisis management capabilities of emergency planning'. (Myers, 2006) This note is given by Myers (2006), and though it cannot be called one of the BCM definitions, but it gives better understanding of the terms and the area of its application. Thus Business Continuity management is aimed to work in both daily and emergency situations; according to the abovementioned citation, it becomes evident, that BCM should both work for the prevention of the critical situations (its primary aim) and for the minimization of the negative consequences for the events which have already taken place. This two-fold role is revealed no matter in which company BCM is implemented. It is difficult to implement BCM notions into the company's performance, but it is even more difficult to make BCM a part of the company's cor porate culture. Many UK organizations at present fail to implement effective plan of prevention critical incidents, which interrupt and may threaten their business activity. Disaster planning and risk management, as well as managing company's benefits is the area which is rarely addressed by the modern businesses. The principal question, which the companies ask, is 'why implement BCM notions How it will positively influence company's performance Are the minimized risks comparable to the costs involved In order to understand how important BCM is for the modern companies, it is interesting to look into the 2006 BCM survey which gives the principal lacks (problems) faced by the companies and thus give the reader basic understanding of... As the report highlights  business continuity Management, or BCM, as it is more commonly known, is a business organization-driven activity that is concerned with developing the organization's ability to continue providing critical services (or business processes) in the event of an interruption.From this paper it is clear that Business Continuity management is aimed to work in both daily and emergency situations; according to the abovementioned citation, it becomes evident, that BCM should both work for the prevention of the critical situations (its primary aim) and for the minimization of the negative consequences for the events which have already taken place. This two-fold role is revealed no matter in which company BCM is implemented. It is difficult to implement BCM notions into the company's performance, but it is even more difficult to make BCM a part of the company's corporate culture.  Many UK organizations at present fail to implement effective plan of prevention critica l incidents, which interrupt and may threaten their business activity. Disaster planning and risk management, as well as managing company's benefits is the area which is rarely addressed by the modern businesses.  The present economy can be characterized as being digital networked economy, which actually has no clear boundaries and thus is more vulnerable to various undesirable invasions (either computer and Internet viruses, or financial frauds).