Sterilization And Aseptic Technique Biology Essay

Sterilization And Aseptic Technique Biology Essay This experiment was done to learn proper way of using aseptic technique and sterilization by isolating pure culture of bacterial. Afterwards, the bacterial cells in a sample and their optical density were determined. First of all, various sterilization methods were introduced. Sterilization is important in a sense that it ensures there is absolutely no contamination in the glassware or apparatus used in the lab. Different sterilization methods are used for different materials. One of them is autoclaving. Autoclaving machine uses high-pressure steam to sterilize and therefore, heat resistant plastics, glass or solutions can be sterilized by autoclaving. As the temperature of the steam is above 100 oC, the organisms cannot survive. Second sterilization method is radiation. As heat sensitive plastics does not have resistance to heat, autoclaving cannot be used and these are often sterilized by using radiation such as UV, gamma-ray or X-ray. The last method is filter sterilization. Some solutions are heat labile, and to sterilize these kind of solutions, filter sterilization can be used. This technique uses the fact that microorganism is around 5micrometer by 1micrometer, and if the filter has a smal ler diameter, microorganisms cannot pass through the filter.(1) In part B, aseptic technique is learned. This technique prevents any kind of contamination while handling the glassware or transferring. To be more specific, it prevents any contaminant to be introduced in the area of interest. The first step of this technique involves wiping the lab bench with 70% ethanol, which would kill most microorganisms. Then, Bunsen burner is turned on, and the movement of the air goes upwards. Therefore, it minimizes the chance of microorganisms landing on the media of interest. In addition, briefly heating glass tube mouths and minimizing the time of opening lids minimizes contamination.(1) Using aseptic technique, streaking technique was used to isolate single colonies. To do this, a pure culture of the target microorganism is taken. Then, with an inocular loop, which is flamed with Bunsen burner until red hot, it cooled down. Afterwards, take a bit of pure culture with the loop and streak lines in the medium. The streaking lines should not cross each other to avoid too much diluting. After streaking, colonies are grown. To count the number of cells, viable cell count method is used. Viable count is only useable with singles colonies and not bacterial lawns. Therefore, in order for cell to have single colonies, appropriate dilution of the bacteria is necessary. The dilution helps for spreading of the cells on the agar. For this, serial dilution, which was introduced last project can be useful. Then, the number of viable cells can be obtained by counting the number of colonies that have developed multiplied by the respective dilution factor. (2) Material and Methods: All procedures are performed according to the BIOL 368 lab manual (Concordia Biology Department 2013) except for the following modifications: for the contamination part, we used shoe, finger, E. coli, and E. coli with 70% ethanol. Results: Colony isolation by streaking First of all, the color of the bacteria in all the plates are thick beige colored. In streak 1, extremely small and many colonies were observed. The size of the colonies were very small, they were circular, opaque and smooth. There are 123 colonies. Streak 2 shows chain of bacterial formation, but the number of the colonies is decreased from streak 1. The number of colonies were 60. They were larger than the colonies in streak 1, opaque, circular and smooth as well. In streak 3, single colonies are observed. None of them was huge, but they were larger than the colonies from streak 2. They were opaque, circular and smooth as well. About 9 colonies were observed. In the 4th streak, no single colony was observed. As a result, single colonies of a pure E. coli strain was successfully isolated. Viable count Table 1. Raw data of viable count of my group. Dilution 10-4 10-5 10-6 Number of colony Too many Too many 252 Viable count (cfu/ml) 2.52 x 109 Sample calculation: Viable count at 10-6 dilution: Since the plate, -6, has 252 colonies which is in the range of 100-300, I picked the plate to calculate cfu/ml. 252 x 10/10-6 =2.52 x 102 x 107 =2.52 x 109 cfu/ml Table 2. Raw data for viable count for all section Dilutions Colony count Group 1 Group 2 Group 3 Group 4 Group 5 Group 6 Group 7 Group 8 Group 9 Group 10 Section 1 10-4 lawn lawn lawn lawn lawn lawn lawn à £Ã¢â€š ¬Ã¢â€š ¬ lawn lawn 10-5 360 lawn 1848 lawn 1028 2168 696 à £Ã¢â€š ¬Ã¢â€š ¬ 3040 1646 10-6 78 287 441 270 234 347 363 à £Ã¢â€š ¬Ã¢â€š ¬ 300 306 Section 2 10-4 920 >300 Lawn Lawn Lawn >300 >300 Lawn Lawn Lawn 10-5 249 >300 590 >300 Lawn >300 >300 406 >300 189 10-6 23 231 189 269 384 222 265 154 180 108 Section 3 10-4 too many >1000 too many too many too many too many too many too many too many too many 10-5 too many >1000 too many too many too many too many too many too many 544 too many 10-6 194 420 258 252 295 217 240 197 79 224 Table 3. Viable count for all section data (for 10-6 dilution) Section Group Number of colonies Cfu/ml 01 1 78 7.8.E+08 2 287 2.87.E+09 3 441 4.41 E+09 4 270 2.70 E+09 5 234 2.34.E+09 6 347 3.47E+09 7 363 3.63E+09 8 9 300 3.00E+09 10 306 3.06E+09 Max 441 4.41E+09 Min 78 7.8 E+08 Average 291.8 2.92 E+09 Standard Dev. 94.40 2.67E+08 02 1 23 2.3.E+08 2 231 2.31.E+09 3 189 1.89.E+09 4 269 2.69.E+09 5 384 3.84.E+09 6 222 2.22.E+09 7 265 2.65.E+09 8 154 1.54.E+09 9 180 1.80.E+09 10 108 1.08.E+09 Max 384 3.84.E+09 Min 23 2.3.E+08 Average 202.5 2.02.E+09 Standard dev. 93.09 9.31E+08 03 1 194 1.94.E+09 2 420 4.20.E+09 3 258 2.58.E+09 4 252 2.52.E+09 5 295 2.95.E+09 6 217 2.17.E+09 7 240 2.40.E+09 8 197 1.97.E+09 9 79 7.9.E+08 10 224 2.24.E+09 Max 420 4.20.E+09 Min 79 7.9.E+08 Average 237.6 2.38.E+09 Standard Dev. 81.55 8.16.E+08 Max 441 4.41.E+09 Min 23 2.3.E+08 Average 242.3 2.42.E+09 Standard Deviation 96.75 1.15E+09 Sample calculation for STD DEV. (section 1):= 94.40 Bacterial cell count by optical density Table 4. Cell density for My Group: OD600 of diluted cultures (Au) E. Coli Count of diluted Culture (cells/ml) Original Culture (cells/ml) Me 0.427 2.18108 2.18109 Partner 0.436 2.14108 2.14109 E. Coli Count of diluted Culture: 0.202 x (5x 108) = 1.01108 Original Culture: 1.01108 x 10 = 1.01109 Table 5. Raw OD600 values for all sections (unit: Au) Group Section 1 (1) Section 1 (2) Section 2 (1) Section 2(2) Section 3(1) Section 3 (2) 1 0.389 0.383 0.359 0.371 0.358 0.365 2 0.368 0.369 0.247 0.447 0.345 0.408 3 0.364 0.343 0.344 0.360 0.323 0.335 4 0.374 0.374 0.390 0.338 0.427 0.436 5 0.415 0.430 0.386 0.368 0.320 0.247 6 0.359 0.357 0.302 0.350 0.379 0.352 7 0.347 0.372 0.354 0.369 0.391 0.364 8 0.362 0.361 0.358 0.328 9 0.370 0.35 1.018 0.350 0.341 10 0.737 0.367 0.368 0.353 0.413 0.322 (>1.96 therefore outlier) Table 6. Diluted Cell Density for all sections (unit: cells/ml) Group Section 1 (1) Section 1 (2) Section 2 (1) Section 2(2) Section 3(1) Section 3 (2) 1 1.95E+08 1.92E+08 1.80E+08 1.51E+08 1.79E+08 1.90E+08 2 1.84E+08 1.85E+08 1.86E+08 1.75E+08 1.83E+08 1.76E+08 3 1.82E+08 1.72E+08 1.24E+08 1.77E+08 1.73E+08 1.96E+08 4 1.87E+08 1.87E+08 2.24E+08 1.85E+08 2.04E+08 1.82E+08 5 2.08E+08 2.15E+08 1.72E+08 1.81E+08 1.62E+08 1.79E+08 6 1.80E+08 1.79E+08 1.80E+08 1.81E+08 1.68E+08 1.64E+08 7 1.74E+08 1.86E+08 1.95E+08 1.75E+08 2.14E+08 1.75E+08 8 1.69E+08 5.09E+08 2.18E+08 1.71E+08 9 1.85E+08 1.93E+08 1.84E+08 1.60E+08 2.07E+08 10 1.87E+08 1.84E+08 1.84E+08 1.77E+08 1.24E+08 1.61E+08 Average 1.87E+08 1.95E+08 1.79E+08 Min 1.72E+08 1.24E+08 1.24E+08 Max 2.15E+08 5.09E+08 2.18E+08 Standard Deviation 1.05E+07 7.43E+07 2.13E+07 Sample calculation: Section 1 group1 student 1: Cell Density = 0.389 x (5x 10^8) = 1.95 x107 Section 1 Average: Average = ((1.95+1.84+1.82+1.87+2.08+1.80+1.74+1.85+1.87+1.92+1.85+1.72+1.87+2.15+1.79+1.86+1.84) x 108)/ 17 = 1.87 x108 Table 7. Diluted Cell Density for all sections, class analysis Class (cells/ml) Average 1.87E+08 Minimum 1.24E+08 Maximum 5.09E+08 Standard Deviation 4.66E+07 Part III. The ubiquity of microorganisms Table 8. The ubiquity of microorganisms Place Observation on TSA plate Observation on Malt Shoe Irregular orange, red, beige opaque Some are large, some are small Some are smooth some are cracked 10colonies None Dirty finger White and yellow all small colonies (4) opaque None E.coli Few circular, smooth, flat, beige colonies (lawn) None E.coli with 70% ethanol None None Discussion: The objective of the experiment is to learn aseptic technique, sterilization, and streaking. Part A involved isolating single colonies by streaking, part B involved viable cell count, part C involved bacterial cell count by optical density and lastly part D involved ubiquity of microorganisms. In part A, a pure E. Coli sample was used to form single colonies by streaking. Four streaks were done in different parts of the plate. As described in the results, 1st streak results in forming smallest and very crowded colonies (123 colonies). The space between the colonies were either very small or even adjacent to each other. The 2nd streak forms a larger and less crowded or less population of colonies (60 colonies). Colonies were found to be further apart from streak 1, but they were adjacent to other colonies, so single colonies were not observed. In the 3rd streak finally, isolated single colonies were observed. This is due to the dilution. As in the streak 1, we have least diluted E. Coli pure sample. Therefore, streak 1 has the biggest cell density, where more colonies would grow. In the streak 2, we streak through the streak 1 once, and so, it is diluted. Then, in the third streak as well, it is even more diluted. This is why we have lesser and lesser colonies in the 2nd an d 3rd colonies. Colonies all seem to have same opaque shape with beige color, but they differ in sizes. 1st streak ones have the smallest and 3rd streak ones have the largest. This is due to the fact that as the number of the colonies are bigger and crowded, there are less space to grow, so it tends to be smaller where as in 3rd streak, isolated colonies have more space where they can grow bigger. In part B, viable count was used to estimate the number of bacterial cells in the sample. Firstly, we prepared 4-fold, 5-fold and 6-fold diluted solutions of E. Coli and they were incubated at 37 degrees Celsius. As we can see in the table 2, 4-fold dilution and 5-folded dilution are too concentrated that bacterial lawn is observed where we cannot apply viable count: they have small viable count to work with and would result in high uncertainty (1). 6-folded dilution appears to be fine to apply viable count and therefore, we used 6-folded dilution to analyze. Looking at the all section data, most of them have the viable counts ranged between 30 and 300. In addition, the average viable count of our section is very close to the class average: 2.38 x 109 to 2.42 x 109 cfu/ml. Also, my group value is very close to the class average as well: 2.52 x 109 cfu/ml. This means that our result is pretty accurate compared to the class result. Speaking of the minimum and the maximum value, there i s a high chance that the errors come from these as these values are furthest from the average. Section 1 has the maximum value which is 4.41 x 109 cfu/ml and section 2 has the minimum value which is 2.3 x 108 cfu/ml. The minimum value seem to be okay but maximum value seem to lie over 300 colonies, and therefore, the biggest error comes from that value. However, none of these biggest error comes from our section, and therefore, we can say that our section value has the least error. Part C was done to take cell density by optical density. CAG12033 was taken and was diluted with LB broth. When analyzing, the group 9 student2s value was 1.018, which appeared to be as an outlier. Grubbs test was done, and it was eventually an outlier, so we excluded it from further analysis. Speaking of the cell density, as there are more and more of cell in the solution, the density increases. As well, the result shows that as absorbance increases, the cell density increases. Comparing the class average to our section average, it is fairly close: 1.79x 108 and 1.87 x 108cells/ml. However, we have the class minimum value which is 1.24 x 108 cells/ml so we have one of the largest errors. But this is not very far from the average value, which is 1.87 x 108 cells/ml it is not the biggest error. The class maximum value however is very far from the class average value: 5.09108 cells/ml. This value is in the section 2 data. Section 1 has the best result over the class with closest averag e value to the class average having no minimum nor maximum values; 1.87 x 108cells/ml which is the same as class average. Comparing my cell density value to the section value, I had 2.18x109cells/ml, whereas the class average was 1.87 x 108 cells/ml. I have a fairly close value and it can be considered that CAG12033 is diluted fairly correctly. Now comparing viable count method to the cell density measured by spectrophotometer, they can be considered the same. The class average value for the cell density was1.87 x 108 cells/ml and the class average result for the viable count method was 2.42 x 109 cfu/ml. They can be considered the same with the following reasons. First of all, for the optical density method, there is an assumption that there are 5 x 108 cells/ml when the absorbance is 1 Au. This is an assumption and is not an accurate value. Secondly, there are experimental errors such as when diluting, the dilution was not done perfectly, where the error would increase as serial dilution was done in viable count part. As a result, factor of 10 difference is quiet big, but within these assumptions and errors, they can be considered as similar. Part D was done to see what contamination looks like and how it is. TSA and malt medium were used to contaminate. Different samples were taken with a sterilized rod and were streaked different parts of the plates on both TSA and malt. They were then incubated at 37 degrees Celsius if it is from internal body or incubated at 30 degrees otherwise. TSA is usually considered the best under neutral to slightly basic conditions and required high N for bacteria to grow. On the other hand, malt is best under acidic condition and high in C and N. Malt is best for fungi. First of all, the shoe was rubbed, and streaked on both TSA and Malt plates. A week later, all different kinds of bacteria were grown. Various colored and various sizes were observed: orange, red and beige. Some were really huge and flat, some were small, opaque and smooth. 10 colonies were observed. On malt, nothing grew. Due to the fact that nothing grew on malt, the colonies have to be bacteria. Another possibilities is tha t malt plate was put in the 37 degrees Celsius which is inappropriate. In quarter of the plate, dirty finger was used to contaminate. 4 colonies of white and yellow were observed. They were all opaque. Nothing grew on malt. In another part of the plate, we put E. Coli sample. Circular, smooth, flat colonies were observed. There were a lot of colonies (bacterial lawn) grown. Again nothing grew on malt. Lastly, we put E. coli with 70% ethanol. Absolutely nothing grew on both malt and TSA. Overall, nothing grew on malt. It is maybe because there was no fungi, or the plates were incubated in the wrong temperature (37 degrees Celsius instead of 30 degrees Celsius). Also, we can say that 70% ethanol kills most of the bacteria or at least enough to prevent them to grow.

Tool Of The Devil: Comparing Satan in Paradise Lost and The Golden Comp

The devil, in literature, is always a catalyst of change for those who encounter him. He is a force working underground, moving against what is widely considered virtuous and good, and it is contact with him that often changes the course of characters lives, and even the world. In Paradise Lost and a book based on it, The Golden Compass, ‘the devil’, in both cases, is an advocate for moving away from the control of God and the Church. Where the stories differ, is in the author’s intent for these actions. In the former, John Milton uses the devil to display how vanity and pride are the sins that halt us in an opportunity to live blissfully, with and under God. Philip Pullman, in his twist on Paradise Lost, The Golden Compass, claims that the original sin was the first, and most essential, step in human beings claiming their free will. He writes the devil (Lord Asriel) as a manipulative, selfish but ultimately admirable character. One who stands his ground and hold s onto his beliefs with an intense passion. Milton’s Satan, on the other hand, comes off originally as charming, but slowly presents himself to be weak and unsure, and his ideals are eventually presented as a mask for his insatiable pride. When Milton’s Satan tricks Adam and Eve into leaving paradise, they are ultimately worse off. Pullman, on the other hand, shows that human beings are essentially crippled without their right and ability to sin and make choices. It is through their differing portrayals of Satan, that Milton and Pullman present their respective cases on how the original sin caused man to lose paradise and eternal bliss, or find free will. When Paradise Lost begins, the vainglorious actions of Satan have resulted in his removal from heaven and placed him on the path to exact revenge against those who have done so. Though, the reader is hardly able to experience any distaste when reading about this man who opposes the consented force of good. He is are charming, dark, fanatical and desperate in his attempts. It is from these characteristics, that the reader may be swayed into viewing him as the protagonist (or even the hero) of the tale. Even C.S. Lewis, famous for his critical detraction of Milton's Satan acknowledges how, "Milton's presentation of him (Satan) is a magnificent poetical achievement which engages the attention and excites the admirat... ... an essential moment that exemplifies our true nature. Lord Asriel represents this, a man who is cunning and self absorbed, who is selfish in his tendencies, but also willing to fight passionately for freedom and independence. Pullman’s Lord Asriel never feels guilt or remorse for his actions, as he fully believes his actions are not wrong. In The Golden Compass, the church is an institution that oppresses it’s citizens, and Lord Asriel has no qualms in fighting against it. It is the truth behind Lord Asriel’s passion, that allows the reader to accept him as a sort of hero, while it is Satan’s doubt and weakness that allows us to eventually cast him aside. The resolve of Lord Asriel reflects Pullman’s insistence on how detrimental our own individual thoughts and determinations are. Though our actions may be negative and even harmful, he believes we are essentially soulless without them. Milton, however, see’s that man has no greater obligation than to serve God, and this is the only way which we can find true peace within. Both authors use Satan as their strongest tool, to reflect where they believe we should put God and the Church in man’s life.

How successful has the government and the Bank of England Essay

The bank of England and the government has worked tirelessly to counter the threat of recession and inflation particularly over the last two years. Both have worked in tandem and introduced a number of economic policies to ensure that the country does not become the target of the dreaded recession. The problems came about due to the sub-prime mortgage problems which originated in the USA. Homes began to get repossessed as home-owners were unable to repay their mortgage arrears. This in turn was felt by the UK economy and the Bank of England was forced to tamper with interest rated to ensure that repossession levels were kept reasonably low. In addition to this we have seen additional economic problems i. e. the folding of Lehman brothers but the bank of England and the government has worked hard to soften the blow. (Jones, 2007,pg 13) The Bank of England has controlled the level of interest rates it sets via the manipulation of short term interest rates and has taken extra care since the credit crunch kicked in 2 years ago. They have controlled the Monetary Policy Committee (MPC). If the MPC thought that the demand was set to rise too fast, then they would have increased the interest rate, but if they thought demand was growing at a slow rate, or maybe even possibly falling, they would then have reduce the interest rate. This was known as the transmission mechanism. (Bernake, 2006, pg 27) The government since November 2006 has introduced many different internal consumer demand changes that affected the general public. Firstly there was consumer borrowing. Many consumers used this method to borrow money in the form of credit cards or loans before the credit crunch but the government revised in at the start of 2007. As the interest rates increased, it became less attractive to borrow at that time as repayments were be higher and still are high. (Jones, 2007,pg 24) Next, there was the issue consumer debt. Because of levels of borrowing at present, higher interest rates meant higher repayment costs. This was known as debt servicing. This left the consumers as a whole with less surplus income to spend as this led to a fall in demand. Mortgage debts were present because most people had to borrow to purchase a home before the credit crunch and the payments on their property varied based on the interest rate but were generally high since 2006. Higher interest rates meant higher repayments which ultimately led to a fall in demand. The Bank of England declined to substantially cut interest rates but a cut of 0. 5% was made in September 2008. Expectations were another point to consider. If interest rates increased then people may have less confidence in the future of the economy and may hold off purchases as they became concerned about a possible fall in income or even worse, the possibility of becoming unemployed. Asset prices may have been affected by interest rates, with an increase in the interest rate meant asset prices may fall. This may be shares or perhaps houses. If asset prices decreased then people felt like they have less money and thus cut back on spending. (Mankiw, 2006, pg12) Many businesses borrowed money from banks and it is this demand changes that affected the interest rates which ultimately affected how much the business owed the bank. One solution is that businesses could have agreed with the lender that funds were only drawn when needed meaning interest would only be paid on amounts drawn and the business would not have to pay interest on unused funds of the loan. The government and bank of England has worked systematically to keep the economy flowing over the last two years where the UK has been on the brink of recession. What this is saying is that they could have predicted how interest rates would fall on rise based on the current state of the economy and the position it had within the world trade. If the economy is doing well then we can say that interest rates will be affected in a way in which we can predict for the future. In this case they may rise but if the economy is doing poorly then they may fall in the future. (Mankiw, 2006, pg22) To conclude one would say that the Bank of England plays a major role in the stability of this country. Without it this country would have no financial stability to be a world player on the trade market like it is now. b) Describe and evaluate the main macro economic policies used by the British government and the Bank of England over the last two years? (november 2006 – november 2008) The government and the bank of England have used a number of macro economic policies over the last two years. They are – Monetary Policy Government has used the monetary policy to ensure a slow steady growth in the money supply which moves in line with the growth of real output, around 1% or 2% per year since 2006. The Bank of England controls rates of interest rates, and by holding interest at a steady level, inflation would also be kept level. ( Bernake, 2007, pg 10) Fiscal Policy The fiscal policy is the policy used by the government to help direct the economy by deciding how much they should spend, which resources to spend money on, how much taxes should be risen or decreased or waived. An example of fiscal policy in use is when the government from 2006 used fiscal policy to change the level of economic activity due ton the credit squeeze. After 1979, the Conservatives believed that using monetary policy to control the money supply was more important but the government from 2006 only highlighted this area of macro economics due to the credit problems. Businesses used the fiscal policy as their main policy as they believe that interest rates played an important part in influencing aggregate demand. They used monetary policy as a back up to fiscal policy. When businesses were faced with a recession in the economy, they did not not welcome the change in the fiscal policy to decrease public spending and increase taxes. When there is a boom in the economy fiscal policy is used by Keynesians to decrease public expenditure and increase tax but since 2006 the opposite occurred. Monetarists used fiscal policy to reach a near balanced budget which they felt would prevent large increases in the money supply and inflation. As monetarists did not believe in the short term counter cyclical policies, they felt that it was important to stabilize the money supply in the medium term to counter the threat of inflation. ( Bernake, 2007, pg22) Incomes Policy The government looked at the incomes policy and aimed to reduce inflation rates by ensuring that the growth rate of incomes is the same as the growth rate of productivity. If the government could slow down the rate of increasing incomes, the incomes policy could restrict the rate at which costs were rising. A voluntary incomes policy was when the government tried to persuade trade unions and firms to accept that wages should not be allowed to increase more than the expected rise in Gross National Product. A statutory incomes policy was when the government passes legislation to limit or freeze increase levels which took place in June 2007. Price Controls Policy The government applied price controls to control inflation rates in Feb 2007.? Price controls sometimes hold prices below the equilibrium level, causing shortages.? If costs rose whilst prices were held down, firms may be unable to make profit.? When cost-push inflation is the main inflation, prices need to be controlled to reduce the problem. The Bank of England was wary of this and welcomed the change. EFFECTIVENESS OF THE POLICIES Monetary Policy Keynesians use monetary policy during a recession and in reverse during a boom. Monetary policy is used to lower interest rates, ease controls on bank lending and hire purchase during a recession. The effect this has on the government objectives was that unemployment would fall due to increased expenditure causing greater demand for goods and services and more need for employees to produce more goods. The threat of Inflation increased due to the less favourable balance of payments due to increased spending on imports. (Bernake, 2006, pg 26) Supply Side Policies Supply side policies also reduced inflation by de-regulating the labour markets and encouraging higher levels of productivity. Supply side economists felt that unemployment levels would drop when there was lower tax and reduced benefit levels but since Nov 2006 the government nor bank of England did not reduce tax. When unemployment had been reduced, the threat of inflation remained low, and if trade unions had less power, it would prevent workers demanding higher wages, which also helped to keep inflation low. By allowing market forces to operate, the bank of England felt that the economic growth would increase, as goods would be supplied where they were needed.? As supply side economists felt that supply factors were important and that they would concentrate on ensuring there was enough supply for consumers, preventing more imports having to be purchased, helping to keep the balance of payments level steady and keeping the economy running in a very shaky period. (Bernake, 2006, pg 29) Price Controls Policy If the government inflation fell by imposing price controls, it can often cause firms to go out of business if costs rise and prices don’t. Firms may be unable to keep employees if costs are rising and they are not making enough profit, causing increased unemployment. Economic growth would deteriorate, as firms may find it difficult to expand. Consumers may purchase goods from other countries if prices are unreasonable causing the balance of payments to decrease, making the UK less competitive. Bibliography Books Jones. C. Introduction to economic growth. Second edition. W. W Norton and company Ltd (2007) Mankiw, G.Macroeconomics. 6th ed. Palgrave, (2006) Journals Bernake, B. Is growth exogenous? Taking Mankiw, Romer and Weil seriously. National Bureau of Economic Research (2006) Edwards T. Human capital and the ambiguity of the Mankiw- Romer-Weil model. Loughborogh University (2007) Felipe, J et al. Why are some countries richer than others? A reassurance of Mankiw Romer Weils test of the neoclassical growth model. Mankiw, et al. A contribution to the empirics of economic growth. Quarterly journal of economics. (2007) Porter M and Stern S. Measuring â€Å"ideas† production function: Evidence from the international patent output. National Bureau of economic research. (2006) Bernake, B. Is growth exogenous? Taking Mankiw, Romer and Weil Seriously. (2007) Felipe, J. Why are some countries richer than others? A reassessment of Mankiw Romer Weils’s test f the neoclassical growth model. Bernake, B. Is growth exogenous? Taking Mankiw, Romer and Weil Seriously. (2006) Edwards T, Human capital and the ambiguity of the Mankiw-Romer-Weil model. (2005) Felipe, J. Why are some countries richer than others? A reassessment of Mankiw Romer Weils’s test f the neoclassical growth model. Zoeyga G and Gylfason T. Obsolescene. International Macroeconomics. 2006

Tax Deduction Tips for Classroom Teachers

In a perfect world, school budgets would overflow with cash for the classroom. Teachers could buy all the supplies they need to optimally instruct their students. The words taxes, deductions, and receipts would apply only to our personal finances. Welcome to reality, teachers. Teaching in the 21st century means you are most likely cash-strapped and scrounging for even the most basic supplies. But if you spend even a dime of your own money to teach your students, you simply must save receipts and claim the costs on your taxes as a deduction. Even the IRS itself reminds teachers each year to claim their classroom expenses on their tax forms. How Teachers Can Minimize Their Personal Taxes You must work in public or private elementary or secondary schools for at least 900 hours as a teacher, instructor, counselor, principal or aide.You may deduct up to $250 of qualified expensesIt is recommended that you keep all of your receipts and documentation in a folder labeled Educator Deductions and the applicable year.Eligible supplies must be ordinary and necessary and they include unreimbursed costs for books, computer equipment including software and services, supplies, and other materials used in the classroom.You do not need to explicitly itemize the expenses. As you can see, its not particularly difficult or time-consuming to save a little money on your taxes with these education deductions. The hardest part is remembering to save receipts and immediately filing them in a single, well-labeled location that you will be able to easily find at tax time. If you have a hard time staying organized and managing the paper piles that come along with the teaching profession, check out these practical tips for winning the paper war in the classroom. Disclaimer: Consult your local tax professional to verify current tax laws in your state.