Microbiology for Environmental Engineering

Microbiology for Environmental Engineering By Georgios Tzelepis Microorganisms play a major role in controlling water and waste quality and every biological process is based on the action of microorganisms. Bacteria constitute an important group of microorganisms which are directly related to Environmental Engineering because of their crucial role in wastewater treatment. They are single celled prokaryotic organisms with a structurally and functionally simple form and various shapes, such as spherical, rod-shaped or spiral. One main characteristic of the bacterial cell is the lack of unit membrane system with exception the cytoplasmic membrane. The identification of bacteria is based on a number of different criteria including their morphological (shape, size), physiological and genetic characteristics. Their reproduction is based on the binary split with formation time of about 20 minutes. Bacteria are sensitive to pH changes and they survive under neutral conditions, although some of them can survive in a highly acidic environment. Regarding th eir survival temperature, they are divided into psychrophilic, mesophilic and thermophilic. Bacteria are very sensitive to temperature changes and they have an optimum growth temperature. (Darakas, 2016) Bacteria have the capacity to degrade the organic substances (pollutants) and this is the reason why they are the most important group of organisms in terms of the public health engineering, since biological waste water treatment processes are based on their activities. The assimilation of pollutants is mainly achieved by the biological self-cleaning of the water thanks to microorganisms and specifically bacteria. The main three points of interest in the wastewater treatment is the microorganisms (bacteria), the included organic matter which constitutes food for microorganisms and the oxygen which is necessary for the energy and survival of microorganisms.    Generally, the metabolic diversity of organisms, and more specifically of bacteria, firstly depends on the energy source. Energy is important for the chemical reactions and is obtained from environmental sources. When the sources are chemicals, the species are called chemotrophs, while when the energy is derived from the light they are called phototrophic species. However, some bacteria have the ability to use both energy sources based on conditions. Second classification is based on the carbon source. When they are organic compounds they are called chemoheterotrophs or photoheterotrophs respectively. Otherwise when inorganic compounds are used, bacteria are called chemoautotrophs or photoautotrophs. Finally, chemotroph bacteria which metabolise organic chemicals for energy are called chemoorganotrophs. Contrariwise, those that use inorganic chemicals are called chemolithotrophs. There are two basic types of metabolism for chemoorganotrophs; fermentation, in which the metabolism of the substrate is without external oxidizing agent, and respiration, in which there is an external oxidizing agent. Both types of metabolism can convert a primary source of energy to one which can be used by the cells. 2.1.1 Carbon source Bacteria that use carbon dioxide for the majority (or all) of their carbon requirements are called autotrophs. The obligate autotrophs that are able to use only CO2 as a source of carbon use simple energy substrates and they are either chemolithotrophs or photolithotrophs. (Singleton, 2005) In autotroph bacteria carbon dioxide from the environment is used to form complex compounds, but also there is the situation that carbon dioxide is incorporated in these compounds and called fixed. There are two common pathways for this fixation, the Calvin cycle and the reductive TCA cycle. Autotrophs are able to thrive in very harsh environments, such as deep sea vents, due to their lack of dependence on outside sources of carbon other than carbon dioxide. (Yates et al., 2016) On the other hand, most of the known species of bacteria are heterotrophic, both aerobic and anaerobic. They use as a main source of carbon complex carbon compounds derived from other organisms, with the most significant the glucose, alcohol, and organic acids. However, there are specialised heterotrophic bacteria capable also of decomposing cellulose (actinomycetes), keratin, hydrocarbons, and other substances. Heterotrophs are only able to thrive in environments that are capable of sustaining other forms of life due to their dependence on these organisms for carbon sources. (Lester Birkett, 1999) 2.2 Energy source Microorganisms, and more specifically bacteria, require food to obtain energy. Phototrophic bacteria are mostly aquatic organisms and obtain energy using radiant energy (light), usually via photosynthesis. This happens through specialized pigments that they contain in order to form energy molecules. Generally, photosynthetic bacteria can be divided in two categories, these who accomplish the photosynthesis with production of oxygen (aerobically) and those without (unaerobically). (Singleton, 2005) Chemotrophs are organisms that obtain their energy by metabolisng chemicals from the environment, through the oxidation of inorganic molecules, such as iron and magnesium. They are divided in two different categories, chemoautotrophs and chemoheterotrophs, with their difference already been described. (Boundless, 2016) Carbon source of heterotrophic bacteria can be either soluble and colloidal organics of untreated waste (BOD) or endogenous carbon microorganisms, i.e. the carbon putrescent dead cells or methanol (CH3OH), which is the best organic substrate to the denitrification. (Darakas, 2016) 2.3 Electron acceptor As mentioned, all the bacterial cells have to convert a primary source of energy into forms that can be used. Some cells can convert a primary energy source to an electrochemical form which consists of a gradient of ions between the two surfaces of cytoplasmic membrane. Chemotroph and phototroph bacteria form high-energy compounds from a primary energy source using different techniques. (Singleton, 2005) Respiration is a type of metabolism in which a substrate is metabolized with the help of an external oxidizing agent. Oxygen can work as the exogenous oxidizing agent having aerobic respiration, or organic oxidizing agents can be used instead in an anaerobic respiration. Despite the fact that the oxidizing agent can be inorganic or organic, in chemoorganotrophs, the substrate is always an organic compound. (Singleton, 2005) Oxygen is the final electron acceptor for the aerobic respiration. The sugar is completely broken down to carbon dioxide and water, yielding a maximum of 38 molecules of ATP per molecule of glucose. Electrons are transferred to oxygen using the electron transport chain (ETC), a system of enzymes and cofactors located in the cytoplasmic membrane and arranged so that the passage of electrons down the chain is coupled with the movement of protons (hydrogen ions) across the membrane and out of the cell. ETC induces the movement of positively charged hydrogen ions to the outside of the cell and negatively charged ions to its interior. This ion gradient results in the acidification of the external medium and an energized plasma membrane with an electrical charge of 150 to 200 millivolts. The generation of ion gradients is a common aspect of energy generation and storage in all living organisms. The gradient of protons is used directly by the cell for many processes, including the active tr ansport of nutrients and the rotation of flagella. The protons also can move from the exterior of the cell into the cytoplasm by passing through a membrane enzyme called the F1F0-proton-translocating ATPase, which couples this proton movement to ATP synthesis. (Kadner Rogers, 2015) Bacteria that are able to use respiration produce far more energy per sugar molecule than do fermentative cells, because the complete oxidation of the energy source allows complete extraction of all of the energy available. (Kadner Rogers, 2015) Respiration can also occur under anaerobic conditions. Anaerobic respiration uses external oxidizing agents such as nitrate (NO3), nitrite (NO2), sulfate (SO42), or fumarate in place of oxygen. Depending on the different types or conditions, the electron donor (substrate) used by chemoorganotrophs in anaerobic respiration is of various organic compounds. The energy yields available to the cell using these acceptors are lower than in respiration with oxygen, but they are still substantially higher than the energy yields available from fermentation. The utilization of CO2as a terminal electron acceptor is limited to a group of bacteria called methanogens and this process requires a strongly reduced environment. This procedure produces methane (CH4) which can be a problem in some instances like landfill sites. (Maier, 1999) All the bacteria have an optimum growth temperature where their growth is faster, while they also have a specific range of temperature into which they can only grow. Most of the bacteria are mesophilic and they grow in temperatures between 15 and 45 degrees of Celsius. Thermophilic are bacteria with growth temperature over 45 degrees of Celsius, while psychrophilic are the bacteria with growth temperature under 15 degrees. 3.1 Low temperature It is well known that bacteria as well as various other forms of life survive and thrive optimally in moderate conditions of temperature, pressure, pH and other environmental parameters. However, there is also evidence of bacteria life in extreme environments. For example bacteria were found to exist in the very acidic river Rio Tino while also bacteria were detected in subzero environments like in Lake Vostok even in depth of 3600 meters, below the surface ice. (Chattopadhyay Sengupta, 2013) At low temperature, bacteria are challenged with a number of difficulties due to decrease in the rate of biochemical reactions that sustain the life. Bacteria taken from low temperature environments were found with increased branched chain, short chain, anteiso and unsaturated fatty acids. They were also found to synthesize more cis fatty acids in preference to trans fatty acids. All these factors are contributing in the increase of membrane fluidity. Moreover, in order to adjust with the low enthalpy and the reduced atomic and molecular motions at low temperature, they achieve flexibility through reduction in strength and number of non-covalent interactions. Finally a high level of post-transcriptional modification of t-RNA by dihydrouridine also has a major role in psychrophiles. Dihydrouridine unsettles the stacking that stabilizes the RNA. (Chattopadhyay Sengupta, 2013) 3.2 High temperature Thermophilic bacteria are common in soil and volcanic habitats and have a limited species configuration. Examination of metabolic pathways and regulatory mechanisms in thermophiles proves that thermophilic bacteria have almost the same properties commonly found in mesophilic bacteria, with the main difference being specific molecular mechanisms, important in high temperature biological stability and activity. As a consequence of growth at high temperature and unique macromolecular properties, thermophilic bacteria can possess high metabolic rates, physically and chemically stable enzymes than similar mesophilic species. Thermophilic processes appear more stable, rapid and facilitate reactant activity and product recovery. Analysis of important biomolecules in thermophilic bacteria has revealed subtle structural differences in proteins, nucleic acids and lipids. Some of these differences have not been observed in mesophilic bacteria. For instance the membrane lipids of extreme thermop hiles contain more saturated and straight chain fatty acids than mesophiles. This allows thermophilic bacteria to grow at higher temperatures by providing the correct degree of fluidity required for membrane function. Finally the explanation for high temperature stability of tRNA in Thermus species is that Thermus transfer RNA contains more guanine plus cytosine bases in the specific base-paired region, which provides greater hydrogen bonding and increased thermal stability. Also, the base-paired region in tRNAs from Thermus contains more thiolated thymidine which provides a stronger stacking force inside the molecule. (Zeikus, 1979) The restoration, maintenance and protection of the environment with the help of biological agents in general and bacteria more specifically are significantly important in terms of sustainability in the environment. Hence, in many cases, bacteria and environmental engineering go hand in hand and both are interdependent on each other. Their main connection is the removal and treatment of the wastes, solid or liquid, from various sources like the industrial, domestic and other. There are many examples of the use of bacteria especially in waste and wastewater treatment, where some useful characteristics of bacteria are used.   Ã‚   4.1 Wastewater treatment Biological treatment is one of the most widely used removal methods as well as for partial or complete stabilization of biologically degradable substances in wastewaters. General characteristics of wastewaters are measured in terms of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), and Volatile Suspended Solids (VSS). Bacteria provide the largest component of the microbial community in all biological wastewater treatment processes, and numbers in excess of 106 bacteria/ml of wastewater are frequently encountered. 4.1.1 Activation Sludge Activated sludge is a process that has been adopted worldwide as a secondary biological treatment for domestic wastewaters. In the activated sludge process the incoming wastewater is mixed and aerated with existing biological sludge (microorganisms). Organics in the wastewater come into contact with the microorganisms and are utilized as food and oxidized to CO2, and H2O. The microorganisms using the organics as food they reproduce, grow, and die. While the microorganisms grow, are mixed together by the movement of air so individual organisms join an active mass of microbes called activated sludge. The wastewater flows continuously into an aeration tank where air is injected to mix the activated sludge with the wastewater and to supply oxygen needed for microbes to breakdown the organic materials. This mixture of activated sludge and wastewater in the aeration tank is called mixed liquor suspended solids and mixed liquor volatile suspended solids. The mixed liquor is sent to the slud ge handling disposal (second part of activation sludge method). A part of this mass precipitates while the rest flows back to the aeration tank in order to maintain sufficient microbial population levels. This is the called activated sludge. The microorganisms in activated sludge generally are composed of 70 to 90% organic and 10 to 30% inorganic matter. The microorganisms generally found in activated sludge consist of bacteria (mostly), fungi and protozoa. 4.1.2 Nitrogen and Phosphorus removal Nitrogen and phosphorus are two essential elements in terms of the waste treatment. The nitrogen compounds and the phosphates existing in wastewaters are very important for the survival of the bacteria although they should be removed in order to avoid problems of deoxygenation and eutrophication in the final recipient. (Bitton, 2010) Nitrification The principal organisms involved in nitrification processes belong into two categories, Nitrosomonas and Nitrobacter. These bacteria are considered to be strictly autotrophs since they derive energy for growth and synthesis from the oxidation of inorganic nitrogen and carbon (CO2) compounds. Nitrosomonas catalyse oxidation of ammonia to nitrite using molecular oxygen, while Nictobacter further oxidize nitrite to nitrate using oxygen derived from the water molecule. It should be mentioned that some some soluble forms of c-BOD can inhibit the activity of nitrifying bacteria since they are able to enter the cells of nitrifying bacteria and inactivate their enzyme systems. (Horan, 1989) Denitrification Denitrification is a process by which certain species of bacteria under anoxic conditions reduce nitrate nitrogen to the gaseous end-products of N2, NO, or N2O which can then escape from solution to the atmosphere. Unlike other nitrogen compounds, the gaseous forms of nitrogen have no significant effect on environmental quality. The presence of oxidized nitrogen and organic carbon are essential properties for denitrification to proceed. Denitrifying bacteria are composed of heterotrophic organisms. The most common denitrifying bacteria are Bacillus denitrijicans, Micrococcus denitrijicans and more. (Horan, 1989) Phosphorus removal The anaerobic-oxic process (most commonly used), consists of a modified activated sludge system that includes an anaerobic upstream of the conventional aeration tank. During the anaerobic phase, inorganic phosphorus is released from the cells as a result of polyphosphate hydrolysis. The energy liberated is used for the uptake of BOD from wastewater. (Bitton, 2010)Removal efficiency is high when the BOD/phosphorus ratio exceeds 10. During the aerobic phase, soluble phosphorus is taken up by bacteria that synthesize polyphosphates using the energy released from BOD oxidation. The anaerobic-oxic process results in BOD removal and produces sludge which is rich in phosphorus. The key features of this process are the relatively low solid retention time and high organic loading rates. (Cheremisinoff, 1997) 4.1.3 Anaerobic Digestion Major applications of anaerobic digestion are the stabilization of concentrated sludges produced from the treatment of especially industrial wastes. The digestion is a complex biochemical process in which several groups of anaerobic and facultative organisms again simultaneously absorb and break down organic matter and can be described as a two-phase process. In the first phase, acid-forming organisms convert the complex organic substrate to simple organic acids. Little change occurs in the total amount of organic material in the system, with decrease in ph . Second phase involves conversion of the organic acids to principally methane and carbon dioxide. The anaerobic process is essentially controlled by the methane producing bacteria. Methane formers are very sensitive to pH, substrate composition, and temperature. If the pH drops below 6,methane formation stops, and there is no decrease in organic content of the sludge. One characteristic of the methane bacteria is that they are hi ghly active in the mesophilic and thermophilic ranges. (Cheremisinoff, 1997) 4.2 Solid Waste Treatment 4.2.1 Composting Composting is the biological decomposition and stabilization of organic substrates. Each gram of decaying compost contains millions of beneficial microorganisms that work to break down organic matter. Of the microorganisms present, 80 to 90 percent are bacteria, including actinomycetes and aerobic bacteria. Aerobic are separated in three different varieties, each of which is active at different phases of the decomposition process. Psychrophilic bacteria (during winter) work on the initial organic matter, at temperatures around 12 degrees Celsius. These bacteria raise the temperature to 20 C, at which time, the mesophilic bacteria take over. These bacteria work at moderate to warm temperatures between 20 and 38 C. At 38 C, the thermophilic bacteria take over, raising the temperature to 70 C. Once this happens, the process starts over again with the addition of new materials. Actinomycete bacteria appear during the late stages of composting to clean up remaining materials that are diff icult for aerobic bacteria to break down. They are responsible for breaking down cellulose, proteins, lignin and starches. References Bitton G., (2010), Activated Sludge Process, in Wastewater Microbiology, 4th Edition, Hoboken, NJ, USA, John Wiley Sons, Inc. Boundless, (2016), Chemoautotrophs and Chemoheterotrophs, Boundless Microbiology, Available from: https://www.boundless.com/microbiology/textbooks/boundless-microbiology-textbook/microbial-metabolism-5/types-of-metabolism-41/chemoautotrophs-and-chemoheterotrophs-285-6153/, [Accessed: 13 January 2017] Chattopadhyay M. and Sengupta D., (2013), Metabolism in bacteria at low temperature: A recent study report., Biosciences, 31, 2, 157-165. Available from: https://www.researchgate.net/publication/236674848_Metabolism_in_bacteria_at_low_temperature_A_recent_report , [Accessed: 10 January 2017] Cheremisinoff N. P., (1997), Biotechnology for Industrial and municipal wastes, in Biotechnology for Waste and Wastewater Treatment, 1-36 Darakas E., (2016), Environmental Engineering: Process of water and wastewater treatment, Thessaloniki, Sofia Publisher. Horan N., (1989), Biological Wastewater Treatment Systems: Theory and Operation., Chichester, England, Wiley Blackwell. Hurst, C.J. et al., (2002), Manual of Environmental Microbiology, 2nd Edition, Washington, ASM Press. Kadner R. J. and Rogers K., (2015), Bacteria. Available from: https://www.britannica.com/science/bacteria/Salt-and-water. [Accessed: 23 December 2017] Lester, J.N. Birkett, J.W., (1999), Microbiology and Chemistry for Environmental Engineers, London, E. F.N. Spon. Maier, E.M. et al, (1999), Environnemental Microbiology, Academic Press Singleton P., (2005), Bacteria in Biology, Biotechnology and Medicine, 6th Edition, Wiley Smith S. R., (2016), Bacteria, Lecture Slides for the course of Microbiology for Environmental Engineering; MSc of Environmental Engineering, London, Imperial College London. Traumann N. and Olynciw E., (1996), Compost Microorganisms, Cornell Waste Management Institue, New York, Available from: http://compost.css.cornell.edu/microorg.html, [Accessed: 10 January 2017]. Yates V. M., Nakatsu C. H., Miller R. V., Pillai S. D., (2016), Manual of Environmental Microbiology, 4th Edition, ASM Press Zeikus, J.G., (1979), Thermophilic bacteria: ecology, physiology and technology., Enzyme and Microbial Technology, 1, 4, 243-252. Available from: http://www.sciencedirect.com/science/article/pii/0141022979900437?via%3Dihub, [Accessed: 27 December 2016]

Gmat -Awa

Guide to Perfect 6. 0 AWA GMAT Score 1. General Structure 1. 1 Argument Intro – Restate argument, point out flaws or state intention to discuss them below 1st Para – First,†¦ 2nd Para – Second/In addition,†¦ 3rd Para – Third/Finally,†¦ Conclusion – The argument is flawed/weak/unconvincing because of the above -mentioned†¦ Ultimately, the argument can be strengthened if/by†¦ 1. 2 Issue Intro – Restate issue, take a position 1st Para – First/One reason†¦ 2nd Para – Second/Another reason†¦ 3rd Para – Third/Perhaps the best reason†¦Conclusion – Acknowledge the other position but re-affirm yours and conclude that it is the stronger. 2. Structural Word (should be all over the essays) Supporting examples – for example, to illustrate, for instance, because, specifically Additional support – furthermore, in addition, similarly, just as, also, as a result, moreover Import ance – surely, truly, undoubtedly, clearly, in fact, most importantly Contrast – on the contrary, yet, despite, rather, instead, however, although, while Decide against – one cannot deny that, it could be argued that, granted, admittedly Ying-yang – on the one hand/on the other handConcluding – therefore, in summary, consequently, hence, in conclusion, ultimately, in closing 3. Templates 3. 1 Argument Intro: The argument claims that †¦. (restate) Stated in this way the argument: a) manipulates facts and conveys a distorted view of the situation b) reveals examples of leap of faith, poor reasoning and ill-defined terminology c) fails to mention several key factors, on the basis of which it could be evaluated The conclusion of the argument relies on assumptions for which there is no clear evidence. Hence, the argument is weak/unconvincing and has several flaws. 1st Para:First, the argument readily assumes that†¦Ã¢â‚¬ ¦ This statement is a s tretch†¦. For example,†¦ Clearly,†¦ The argument could have been much clearer if it explicitly stated that†¦ 2nd Para: Second, the argument claims that†¦. This is again a very weak and unsupported claim as the argument does not demonstrate any correlation between†¦. and†¦ To illustrate,†¦ While,†¦ However,†¦. indeed†¦. In fact, it is not at all clear†¦ rather†¦. If the argument had provided evidence that†¦.. then the argument would have been a lot more convincing. 3rd Para: Finally,†¦ (pose some questions for the argument)†¦..Without convincing answers to these questions, one is left with the impression that the claim is more of a wishful thinking rather than substantive evidence. Conclusion: In conclusion, the argument is flawed for the above-mentioned reasons and is therefore unconvincing. It could be considerably strengthened if the author clearly mentioned all the relevant facts†¦. In order to a ssess the merits of a certain situation/decision, it is essential to have full knowledge of all contributing factors. In this particular case†¦. Without this information, the argument remains unsubstantiated and open to debate. . 2 Issue Intro: Many/some people think that†¦. Others†¦.. (restate) The issue is a controversial one but a closer examination reveals that†¦. (take a position)†¦ for several reasons. 1st Para: One reason is that/for†¦ For example,†¦ Furthermore,†¦ Clearly,†¦ 2nd Para: Another reason is that/for†¦ To illustrate,†¦ As a result,†¦ 3rd Para: Perhaps the best reason is (that)†¦. Specifically,†¦ Moreover/In addition†¦. In fact,†¦. Therefore,†¦. Conclusion: In summary, while there are arguments to be made for both sides, it is clear that there are greater advantages to†¦. repeat the reasons). Certainly,†¦.. outweigh†¦Ã¢â‚¬ ¦. Hence,†¦. (re-affirm your position) 4. Going from the templates to full-fledged essays 4. 1 Argument ESSAY QUESTION: The following appeared in the editorial section of a national news magazine: â€Å"The rating system for electronic games is similar to the movie rating system in that it provides consumers with a quick reference so that they can determine if the subject matter and contents are appropriate. This electronic game rating system is not working because it is self regulated and the fines for violating the rating system are nominal.As a result an independent body should oversee the game industry and companies that knowingly violate the rating system should be prohibited from releasing a game for two years. † Discuss how well reasoned you find this argument. Point out flaws in the argument's logic and analyze the argument's underlying assumptions. In addition, evaluate how supporting evidence is used and what evidence might counter the argument's conclusion. You may also discuss what additional evidence could be used to strengthen the argument or what changes would make the argument more logically sound.YOUR RESPONSE: Quote: The argument claims that the electronic games rating system, although similar to the movie rating system, is not working because it is self regulated and violation fines are nominal, Hence, the gaming rating system should be overseen by an independent body. Stated in this way the argument fails to mention several key factors, on the basis of which it could be evaluated. The conclusion relies on assumptions, for which there is no clear evidence. Therefore, the argument is rather weak, unconvincing, and has several flaws.First, the argument readily assumes that because the electronic game rating system is self regulated, it is not working well. This statement is a stretch and not substantiated in any way. There are numerous examples in other areas of business or commerce, where the entities are self regulated and rather successful. For instance, FIA, the Formula1 racing organization is self regulated. Yet, the sport is very popular and successful, drawing millions of spectators around the world each year. Tickets are rather expensive, races are shown on pay-per-view, and nearly all drivers are paid very well.Another example is the paralleled movie rating system that the argument mentions. The author fails to clarify whether it is working well, but it is clear that the movie rating system is pretty well received by people, who often base their decisions to go see a movie with kids or not on the movie rating. It has never been a case when someone would feel cheated by the movie rating and express disappointment afterwards. Since the movie rating system is also self regulated, it follows that this regulatory method is working pretty well and it is not obvious how it can be the reason for the poor electronic game rating system.The argument would have been much clearer if it explicitly gave examples of how the self regulatory system led to bad r atings and customer dissatisfaction. Second, the argument claims that any violation fees for bad electronic game ratings are nominal. It thus suggests that this is yet another reason for the rating system not working. This is again a very weak and unsupported claim as the argument does not demonstrate any correlation between the monetary amount of the fines and the quality of the electronic game rating system. In fact, the argument does not even draw a parallel with the mentioned movie rating system and its violation fines.If any such correlation had been shown for the movie rating system, which supposedly works well, then the author would have sounded a bit more convincing. In addition, if the argument provided evidence that low violation fines lead to electronic game manufacturers to ignore any regulations with respect to the game rating system, the argument could have been strengthened even further. Finally, the argument concludes that an independent body should oversee the game industry and companies that violate the rating system, should be punished.From this statement again, it is not at all clear how an independent regulatory body can do a better job than a self regulated one. Without supporting evidence and examples from other businesses where independent regulatory bodies have done a great job, one is left with the impression that the claim is more of a wishful thinking rather than substantive evidence. As a result, this conclusion has no legs to stand on. In summary, the argument is flawed and therefore unconvincing. It could be considerably strengthened if the author clearly mentioned all the relevant facts.In order to assess the merits of a certain situation, it is essential to have full knowledge of all contributing factors. 4. 2 Issue ESSAY QUESTION: â€Å"Poor health and high stress levels diminish the productivity of today’s office workers. In order to maximize profits, companies need to provide white-collar employees with free exercise facilities and free wellness classes. † In your opinion, how accurate is the view expressed above? Use reasons and/or examples from your own experience, observations, or reading to develop your position. YOUR RESPONSE: Quote:Some people think that productivity at work could be increased if workers are provided with free exercise facilities and wellness classes, as this will improve the workers health and diminish the level of stress in the office. Other people support the claim that people should manage their own health and stress level outside the work space. The issue is a controversial one but a closer examination reveals that companies that promote healthy living among their employees are indeed more productive. One reason is that people often do not find the motivation or the energy to o to a wellness class and exercise outside of work. Most people are usually very tired by the end of the work day and have other family duties or priorities to worry about. For example, do ing grocery shopping, cooking, picking up the kids from practice, etc. Therefore, it is very difficult for such people to make time for exercising and maintain healthy habits. As a result, the stress from a long day of work at the office gets carried over to the next day and the pattern repeats. Eventually, the health of those people worsens and their productivity on the job diminishes.Another reason is that people often find it attractive to do what their friends or colleagues do. For instance, if five colleagues of a worker join a pilates class and are happy about it, they then tend to recommend it to the worker in question and she will eventually join the class. Contagious behavior such as this can be very easily achieved on the job if pilates classes are offered, because then the discovery of the opportunity and the motivation to join are easily found. Hence, exercising at work becomes a very comfortable activity easily fit into a schedule and promotes the health and happiness o f the employees.They not only feel better heath-wise after exercise, but also strengthen relationships with co-workers by doing activities together. In a way, this whole experience can be viewed as team building. Consequently, workers are more energized, alert and therefore productive in their jobs. Perhaps the best reason is that by providing free exercise facilities and wellness classes companies improve their image and become attractive places to be at for future employees. Not only can such companies attract more viable candidates for new openings, but they can also retain longer the employees they already have.To illustrate this point, let us take Google for example. The company was recently ranked as the best one to work at. One of the main criteria for achieving this rank was the fact that the company takes very good care of its employees in terms of encouraging healthy living. There are numerous sports facilities on the Google campus which people are encouraged to use. Those include gyms, swimming pools, volleyball courts, massage chairs, etc. Personal trainers are also available for free for anyone that needs them. There is also a health center facility on site.With that kind of environment it is difficult to not take advantage and live a healthy living, resulting in better productivity on the job. In summary, while there are arguments to be made for both sides of the issue, it is clear that there are much greater advantages for companies to provide their workers with free health facilities and classes. Workers find it not only much easier to take advantage of such opportunities on site, but also are much more motivated to do so there. Participating in sports activities improves the workers' mood, desire to work hard, keeps them healthy, and creates a bond among workers.As a result, this translates to a better productivity of the workers and ultimately to maximized profits for the company. 5. Final tips During the tutorial type in a few sentences in t he mock essay window to get used to the keyboard. Again during the tutorial, jot down on your notebook the basic structure of your essays or the opening sentences in case you get too nervous and forget them when the clock starts ticking. Write as much as you can. Try to write at least 500 words per essay. Always have the e-rater in mind as your potential reviewer.Remember that the human rater will make every effort to grade just like the e-rater. In that sense, keep your structure and volume in mind over actual quality/content. Be careful of spelling mistakes. Double check words that you normally know you misspell (e. g. exercise). Try to finish 2-3 minutes before time is up so you can slowly re-read your essay for the purposes of spell checking. Do not reorganize/delete sentences/paragraphs with less than 2 min left. No matter how great you thought your essays went, try to stay humble and focused – remember this was just a warm-up and the real stuff hasn't started yet!Good l uck! —————————- Here is an essay I wrote for a PR Test – Graded a 6. 0 (normally they grade harder than real thing) Prompt: â€Å"The autonomy of any country is based on the strength of its borders; if the number of illegal immigrants entering a country cannot be checked, both its economy and national identity are endangered. Because illegal immigrants pose such threats, every effort must be made to return them to their country of origin. † Assignment: Discuss how well-reasoned you find this argument.In your discussion, be sure to analyze the line of reasoning and the use of evidence in the argument. For example, you may need to consider what questionable assumptions underlie the thinking and what alternative explanations or counterexamples might weaken the conclusion. You can also discuss what sort of evidence would strengthen or refute the argument, what changes in the argument would make it more logicall y sound, and what, if anything, would help you better evaluate its conclusion. â€Å"This argument relies heavily on unverified assumptions and has a very extreme conclusion.The author fails to make logical connections between the evidence provided and the conclusion that all illegal aliens must be returned to their country of origin. The first problem with the argument is that it suffers from multiple unsubstantiated claims. The first evidence that is given to support the extreme conclusion is that the autonomy of any country is based on the strength of its borders. This statement is also extreme because it infers that every countries autonomy could be ranked by the strength of its borders. There are many European countries that have very little strength exerted at the borders, but still maintain autonomy.The author should clarify this statement by grouping countries together or using a more vague statement that would include most countries but not all. The next statement in the a rgument is conditional phrase stating that the more illegal immigrants that enter a country the worse off the economy and national identity will be. While this statement might be true for some countries it is certainly not true for all countries. The very foundation of early US society was based on immigrant labor and culture that brought from over the sea. There are still many countries whose economy is heavily dependent on immigrant labor.Even though many economist feel this statement is true in the US today, most would disagree that this statement is true of all countries. The final portion of the author's argument is the conclusion. The conclusion states that the because of disadvantages mentioned earlier all illegal immigrants must be returned to their country of origin. Although this statement might appear to be a logical conclusion of this extreme argument it fails to take extra information into account. The author doesn't give any indication on how extreme these problems wil l be or how costly it will be to return the amount of illegal aliens to their home country.What if the cost to the economy was half the amount that it would cost to send all of the immigrants back to their country of origin? The author could use some monetary figures to prove that some savings would be incurred if all illegal immigrants were deported. In conclusion, the argument suffers from logical flaws and makes an extreme conclusion based on unproven assumptions. The addition of hard examples and connections between the statements would prove to strengthen the argument. † *This just shows you how you don't have to write great to get a good score*

America Needs the Space Program - 928 Words

It’s in everyday life, it is seen every day and where it comes from is not appreciated the way it should. Most of the technology that is in the world today is possible because of the space program. Computers used to take up a whole room just for one, but NASA saw that they could not take a computer the size of a room into space, so they invented the laptop, something that probably would not have been invented without NASA. After this people looked at NASAs ideas and made them better. This is how any technology is evolved, someone has to create a raw idea and then other people will just keep improving it. Because the space program has influenced our society so much it has proven time and time again why America needs the space program. After WWII, the US and Soviet Union started to develop a new kind of missile program, not for aiming them at other countries, but aiming them at space, this period of time was known as the Space Race ( A Brief History of Space Exploration).Americ a was launched into space because JFK knew the that America needed to restore its confidence and that America would not only meet with the soviets, but surpass them, and from that he made the goal of landing a man on the moon within the decade (Space Program). There were three main scientists from three different countries who started to design rocket engines for space travel. Those scientists were: Konstantin Tsiolkovsk from Russia, Robert Goddard from the US, and Hermann Oberth from Germany ( AShow MoreRelatedSpace Exploration : The Space Program Essay1659 Words   |  7 Pages The Space Race sparked an era of ingenuity and technological advancement that no one had seen before the Cold War. Once Russia launched Sputnik (â€Å"traveler† in Russian), the world’s first man made satellite, on October 4th, 1957 the race was on. The race also lead to several advancements in technology and education because of increased funding to make sure America got ahead of Russia. Many of these technologies are used today and many don’t know they are a result of the space program. From LEDs toRead MoreThe Importance Of Space Exploration1622 Words   |  7 PagesSpace exploration is declining because funding for it has gone down. Public and government interest has waned as there does not appear to any direction or goal; whereas, other countries have dramatically increased their commitment to space. Examples are China, sending men to space and India, which is sending satellites to Mars. Space exploration drives economies and consequently, these other count ries are becoming industrial powerhouses. America is in danger of losing its place as a leader in everythingRead MoreThe Current State Regarding Theu.s Space Exploration Program1177 Words   |  5 PagesSummary Cognitive Anthropologist Bob Deutsch discusses the current state regarding the U.S’ space exploration program as a whole. He particularly points to the fact that America seems to have lost its zeal to explore due to the fact that they are so caught up in their own â€Å"hunkered down existence†. For example, it was only a little over a decade ago that mars passed close to the earth; relatively a stones throw away and people looked up but even more said â€Å"so what?† and moved on. TheyRead MoreNASAs Changing Problem Essay613 Words   |  3 PagesNASA’s Changing Problems Has anyone ever realized that the National Aeronautics and Space Administration (NASA) is slowly getting shut down for the whole world to see? This is changing NASA very much. It lost its shuttle program, it had budget cuts to missions to earth, and even a cut in education. NASA was founded by Dwight D. Eisenhower. NASA is most known for being the first company to send a person to the moon. It is easy to tell that NASA’s changed and is changing right now. The big questionRead MoreEssay on Frontier of the Future: America ´s Space Exploration629 Words   |  3 PagesIn the early 60s, President John F. Kennedy led America into a space race against the Soviet Union. American men and women across the nation backed this goal, allowing NASA to take great leaps in advancing its space exploration programs. This unified nation fulfilled its goal, and Neil Armstrong became the first man to walk on the moon. However, since then, America’s space exploration has only declined. Fun ding for NASA has been drastically cut, thus greatly limiting the opportunities for exploringRead MoreNasa s The Manned Space Flight Program1240 Words   |  5 Pagesthe manned space flight program is quickly reaching extinction. It marks a sharp contrast with the Apollo space program that at its peak captured the American imagination. David L. Chandler reports of that time, â€Å"With goose bumps and white knuckles, people followed the crackly radio reports of that first lunar footfall, and they lionized its heroes with tickertape parades† (Chandler, 1). Now, there is none of that level of interest in the space program. In a short span of time, space travel becameRead MoreThe Eagle Has Landed Essay913 Words   |  4 Pagesimportant decade during the Space Race, because American perseverance overcame a more advanced Soviet space program and reached the moon. Accordingly, national leaders of the sixties were a huge driving force behind the Space Race as they inspired their p eople to literally shoot for the moon and take the lead in the ‘Space Race’. Likewise, ambitious projects like Apollo and Mercury really took off in the nineteen-sixties and paved the way to the first American in space and eventually to the moon.Read MoreThe Space Race to the Moon Essay1126 Words   |  5 PagesUnion, to win the Cold War. Both nations wanted to be the first on the moon, therefore, the United States strived to win the Space Race and consequently have victory over the Cold War. Given these facts, the Space Race not only helped the Americans have advantage in the Cold War, but has also affected America to this day. It was a difficult moment in the late 1950s in America. The Cold Ward was heating up on a political level. Suddenly, that all ended when the Soviet Union launched Sputnik 1 onRead MoreUp, Up and Away with the Space Race1225 Words   |  5 PagesIn 1965, NASA’s annual budget was $5.2 billion; this money was spent to heat up the Space Race (â€Å"Project Apollo†). The Space Race and its competitive nature is best illustrated in this passage from John F. Kennedy’s Address at Rice University on the nations space effort, â€Å"We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challengeRead MoreThe Challenger Disaster And Its Impact On Space Travel1708 Words   |  7 Pagessymbolized that space travel is a challenging endeavor which bears it’s own set of risks, especially when the ent irety of the shuttle program was plagued with issues up until the Challenger incident. Initially, America put a ton of resources into the space program in order to achieve the goal of winning the Space Race. Once that goal was achieved, America’s space program was scaled down to a fraction of the previous budget (space.com article). Out of the small budget, the shuttle program came into existence