RGB LEDs Colour Mixing Controller Lab Report Example | Topics and Well Written Essays - 1000 words - 1

RGB LEDs Colour Mixing Controller - Lab Report Example The major aim of designing a light emitting diode mixing controller is largely for managing and controlling light emitting diodes colour points. It is also responsible for maintaining the controlled light colours to produce desired lighting effects. Another aim is to reduce cases of failed colour lighting in producing the RGB effect. For these aims to be achieved, specific objectives are necessary. Firstly, identification of all required equipment such as LEDs and power sources with appropriate current feeding is made. Secondly, the main controller is broken down into stages such that each stage can produce an independent controller for the purposes of achieving desired lights at each stage. Lastly, every stage involved use of assurance techniques to ensure that required voltages were attained. Introduction Lighting systems have been identified as some of the most beautiful creations of electronic engineering. Achieving lighting effects depends on the equipment used, mostly, LEDs. Given that most lighting designs employ the single LED technology, RGB employees the use of three Light emitting diodes, each with a corresponding primary colour. Designing and implementing RGB LEDs controller is a complicated multistage process. Achieving accuracy has been identified as one of the greatest milestones in practical electronic engineering design (Box 2010).

Extracting DNA From Living Samples

Extracting DNA From Living Samples Karen Stevenson Introduction Collecting DNA samples from animals is often difficult and stressful for the animal, so non-invasive methods of collection are needed. Extracting DNA from animals usually involves one of three methods: Destructive sampling involves the organism having to be killed to get the tissues needed for genetic analysis.  Non-destructive or invasive methods require a tissue biopsy or blood sample. These are the most ethically acceptable and humane ways to extract DNA from living organisms as they do not destroy the animal or its habitat and often any DNA from feathers, hair, skin, droppings, etc. can be used, although DNA samples do degrade over time which will subsequently decrease the accuracy of test results. Freeland (2005) discusses a number of processes for DNA preservation including the method we used in the class experiment which is described in this report. High quality DNA shows up in bright contrasting bands on the electrophoresis gel but poor quality DNA displays a blurred or smudged look. Gender will show up as either one or two separate bands. Unlike in mammals where the heterogametic male (XY) will show up as two bands and the homogametic female (XX) will show up on the gel as one band, with birds, this is the opposite and the male is the homogametic and his ZZ genotype shows up as one distinct band while the heterogametic female ZW genotype shows up as two distinct bands on the gel. It is very difficult to determine the gender of very young chicks because there are no visible dimorphisms yet and poultry producers need to determine the sexes well before the animals begin to mature. Modern molecular genetic methods mean we can profile for individual genomes from very small amounts of DNA, whereas historically much larger samples were needed to get accurate results. In this experiment we followed procedures outlined by Hogan, Loke Sherman (2012) in our Prac manual to extract DNA from three tissue types of a domestic chicken to determine the sex of the sample and also to compare the quality and amount of DNA from the three samples. Materials and Methods Tissue Samples. Feathers, muscle tissue and blood samples were supplied by the technicians in the lab. The tissues were taken from a domestic chicken Gallus gallus domesticus. DNA Extraction from Blood, Feather and Muscle Samples We extracted our Our DNA with the Quiagen DNA purification kit DNeasy Blood Tissue Kit (2012). PCR is a faster and more sensitive method of amplifying DNA than cloning, and it produces similar results. We used bird sexing primers to build up the gender-specific loci CHD1W and CHD1Z, which allowed us to determine the gender of the chicken from a method developed by Fridolfsson and Ellegren (1999) using universal avian sexing primers 2250F and 2718R. The class results were collected and graphed so that our individual results could be compared. Negative control, male and female controls were used to conclude whether our hypothesis that Blood and tissue samples would yield a better quality of DNA than feather even though these methods are more invasive than extracting DNA from the blood spot in a feather shaft. In this experiment we extracted DNA from a blood clot in the feather as in the Horvath, Martinez-Cruz, Negro and Goday (2005) procedure, which showed that this was more successful than using material from the tip and this blood clot sample took longer to deteriorate than the tip sample. We did not know how old the feathers were, nor the age of the bird. DNA extraction procedures work by lysing cells, which causes the cell membrane to break free from the cell. Proteinase K can be added to detach the proteins and RNA can be removed with the RNAse. The DNA is then precipitated out using ethanol and further improved using PCR methods and visualized using the electrophoresis procedure. The Section containing the blood spot was cut out using a sharp pair of scissors and cut into tiny pieces and added to 180 µL of Buffer ATL before digestion with Proteinase K (180 µL pipetted into a sterile 1.5 mL microfuge tube) was then incubated at 56ËÅ ¡C for 30 minutes (briefly mixed in the vortex every 10 minutes), after which the cells had been lysed. To precipitate the DNA we added 200 µL of 95% ethanol (AR grade) and mixed in the vortex for a further 15 seconds. The lysed DNA was then pipetted into the DNeasy Mini spin column and centrifuged at 8000 rpm (6000 x g) for 1 minute, binding the DNA to the membrane in the spin column, ready for washing. The spin column was placed in a new microfuge collection tube in which 500 µL Buffer AW1 was pipetted, centrifuged for 1 minute at 6000 x g (8000rpm) and the flow-through was discarded. Again the DNeasy spin column was placed into a new collection tube, 500 µL of Buffer AW2 added and centrifuged for 3 minutes at maxi mum speed (13 – 14,000 rpm), removed from the flow-through (which was discarded in hazardous waste receptacle), placed back into the collection tube and centrifuged again at maximum speed for a further minute to remove any ethanol. The spin column was then removed from the tube (which was discarded). After placing the spin column into a clean 1.5mL collection tube it was labelled appropriately and 100 µL of Buffer AE was pipetted straight onto the centre of the DNeasy membrane and incubated at room temperature for 1 minute, centrifuged for 1 minute at 6000 x g (8000 rpm) to elute it. The DNA was now pelleted in the bottom of the tube, so the spin column was discarded and the pellet stored in its tube in a cold box at -20ËÅ ¡C. Electrophoresis Method During electrophoresis, the negatively charged DNA fragments travelled towards the positive cathode causing the smaller protein fragments to move quicker than larger particles. The DNA was visualized as bright bands on the gel, which had been stained with GelRed which is a chemical used to increase mutation rates, multiplies the product and is assumed to be carcinogenic. The agar gel and TAE buffer had been prepared earlier in the microwave and allowing the gel to cool to 50 °C. GelRed was carefully added to 150mL of gel for a final concentration of 0.5 µL mL-1.The casting tray was carefully put into the gel tank with the black moulding gates at both ends. The comb was inserted after the gel had been poured into the tray inserted, then left for 30 minutes at room temperature to set. 10 µL of the DNA chicken feather sample we extracted previously was mixed with the 6x loading dye into a fresh microfuge tube. Wearing rubber gloves, we removed the black casting plates and the comb and then added the TAE buffer until the entire gel was submerged by 5mm. The first and last wells had molecular weight markers ÃŽ »HindIIIand 2-log ladder added and our DNA samples were pipetted into an empty well, noting the position. We applied the cover and connected to the power unit and ran it for 60 minutes at 120V. The DNA proceeded to float from the negative cathode (black cable) to the positive anode (red cable). When finished, we removed the gel tray and transferred it on a plastic container to the Gel Doc System for visualizing the images. PCR method We used the Polymerase Chain Reaction method to expand the DNA so that it could be viewed using electrophoresis. The PCR procedure involved cycles of heating then cooling the DNA which enabled the helix to unwind and bind. We prepared the Mastermix negative and positive controls using 40 µL of the PCR Mastermix and 10 µL of the DNA sample mixed into a 0.2mL PCR tube. Each group had individually calculated amounts using the chart in the Prac manual. We prepared tubes for male control, female control and one negative control (these were provided by the lab). We then placed the tubes into a thermo-cycler and initiated the program which had been perfected to augment the CHD1W and CHD1Z genes using the primers. When this was done, the DNA was then put on a 1% agar gel comb (that had been microwaved and cooled to 50ËÅ ¡C) in a 1 x SB buffer solution for 20 minutes. Wearing gloves, we added 15 µL of 3 x GelRed solution to 150mL of agar gel. We prepared the DNA samples by mixing 10 µL of PCR with 2 µL of 6x loading dye, pipetted it into the gel combined with 5 µL of a 100bp molecular weight marker. The sample was pipetted into an empty well in the gel, location documented and after closing and securing the lid, the electrophoresis unit was run at 300V for 20 minutes. When the gel had finished running the power was turned off, gel removed carefully and put into a plastic container and transported to the Gel Doc unit. The bands were then visualised using the Gel Doc System. Results The class groups successfully extracted DNA from all three types of tissue. Due to incorrect or absent labelling of DNA samples, we were unable to use some of the gel images in our report. Figure 1 shows the Gel electrophoresis from a co-operative class Muscle and Blood DNA extraction using Qiagen 2012, DNeasy Blood Tissue Kit, with blood showing up in more distinctive bands, muscle failing to show clear bands and feather samples extracted (on a separate gel image) displayed poorly using electrophoresis. Hogan, Loke Sherman (2012) explain how the DNA concentrations are measured by comparing the brightness of the sample to the 2log Molecular Weight Marker over the amount of DNA pipetted into the well. Figure 1: Blood muscle DNA extraction using (Qiagen 2012, DNeasy Blood Tissue Kit) Figure 2: Feather DNA extraction using (Qiagen 2012, DNeasy Blood Tissue Kit) After extraction and visualization using electrophoresis, our samples were diluted give comparable concentrations. If the band was too faint or not even visible we left it undiluted but most of muscle and blood samples were dilute. Figure 2 shows the Gel electrophoresis from our feather DNA extraction sample with no discernible results. This was expected. Table 1: Mean nucleic acid concentrations muscle, blood and feather DNA extraction using nanodrop technique From table 1, results show us the average DNA concentration of the three tissue types and reveals that compared to feather, muscle samples provided the best quality of extracted DNA, followed closely by the blood samples. Our test yielded 5 muscle samples, 6 feather samples and 8 blood samples as well as the 2 unspecified class samples. Because 1 feather sample and 1 blood sample failed to clearly show any visible DNA (see figures 1 2), they influence the averages. In the face of this, however, the resulting average sample DNA concentrations reveal that muscle still produced the highest class of extracted DNA in comparison to the blood samples. The feather sample still showed the poorest DNA quality, which related with our expected outcomes. Ladder Male control Female control Negative control Jack’s sample DNA Sample DNA Karen Feather DNA Sample Negative control Female control Male control Ladder Figure 3 shows the Gel electrophoresis from our feather DNA extraction sample with the male, female and negative controls. DNA had been amplified from the extraction and visualized using electrophoresis to determine the sex of the bird that our sample was taken from. Results successfully indicate that sexes were able to be determined. Our PCR result matched the expected result and we determined our sample to be ZW female and Jack’s sample to be ZZ male. This experiment matched the Fridolfsson and Ellegren (1999) procedure except that we used a 1% agar gel to visualize the DNA fragments via electrophoresis and Fridolfsson and Ellegren used a 3% gel as well as our use of a commercial kit (Quiagen 2012). Discussion The quality of DNA extracted varied between our different tissue samples although all we were able to amplify all of them using the non-invasive technique PCR. Extracting DNA from a blood clot of a feather is an option when alternative methods (blood or muscle) are not suitable. The destructive muscle samples provided a better class and measure of DNA in comparison to the feather samples, however destructive methods of DNA extraction necessitate the slaughter of the organism and is not typically ethically acceptable particularly when endangered species are involved. Invasive blood sampling provided a high quality of DNA in terms of results and should be used in preference to destructive methods if non-invasive methods are not possible. The disadvantage of blood sampling is that if the procedure is done in the field, it necessitates the capture of the organism to extract the blood sample as well as the storage while out in the field as DNA deteriorates over time. Although DNA from fea ther samples gives a lower quality than the other two methods discussed, they are usually easier to obtain in the field because capture, plucking and release are far less invasive that taking blood or killing the animal for muscle tissue (Mundy et al. 1997) and usually can be collected from nests or off the ground without having to involve capturing the animal at all. This experiment was conducted over a number of weeks. DNA deteriorates over time and storage is therefore very important. Freeland (2005) discusses the importance of preserving DNA to circumvent DNA molecules from re-arranging and so affect the results when amplified by the PCR technique. We froze the DNA at -20 °C to preserve the samples in between both practical sessions. While performing the practical sessions, our DNA was generally kept at room temperature which could possibly have caused some deterioration but this is not very likely to cause large variations of DNA quality as all our samples were exposed to the same conditions. Cold-boxes were used to store the DNA samples but all products including the DNA were kept at room temperature for the duration of both practical’s and this could easily have been avoided by asking the students to me mindful of the importance of preserving the DNA in order to get better quality DNA for extraction. References Freeland, J (2005).  Molecular Ecology. Wiley. Chichester. Fridolfsson, A and Ellegren, H. (1999). A simple and universal method for molecular sexing of non-ratite birds. Journal of Avian Biology. 30, 116 – 121. Hogan, F., Loke, S., and Sherman, C. (2012)  SLE254 Genetics: Practical Manual 2012~ Sex Determination of the Domestic Chicken (Gallus Gallus).Deakin University. Burwood. 1-46. Horvath, M. Martinez-Cruz, B. Negro, J. Kalmar, L and Goday, J. (2005). An overlooked DNA source for non-invasive genetic analysis in birds. Journal of Avian Biology. 36, 84-88. Mundy, N. Unitt, P., and Woodruff, D. (1997). Skin from feet of museum specimens as a non-destructive source of DNA for avian genotyping. Auk 114, 126-129. Qiagen. (2012).  Sample Assay Technologies: DNeasy Blood Tissue Kit.Retrieved September, 11th2012 Taberlet, P. Waits, L. and Luikart, G. (1999). Noninvasive genetic sampling: look before you leap. Trends in Ecology and Evolution. 14, 323 – 327.

Correlation between 8th grade mathematic CMT scores and mathematic CAPT

Correlation between 8th grade mathematic CMT scores and mathematic CAPT scores Introduction: Standardized testing, specifically â€Å"high-stakes testing†, has become a topic of debate for many years. â€Å"High-stakes testing† is associated with states that require successful performance on a standardized test for graduation, an â€Å"exit exam†. Is this the trend in public education? As an educator in Connecticut, should I expect â€Å"high-stakes testing† in the future? The State of Connecticut Legislature created a statue (Section 10-14n) that mandates statewide standardized testing for students in 4th, 6th, 8th and 10th grade. The tests assess performance tasks and a set of specific skills, which are aligned with the Connecticut Common Core of Learning and National Standards. Students are evaluated against that set of specific skills, not each other (Connecticut Mastery Test Program Overview 14). In 4th, 6th and 8th grade, students take the Connecticut Mastery Test (CMT) and the Connecticut Academic Performance Test (CAPT) is administered in 10th grade. The movement for standardized testing began in 1985 with the CMT and the testing trend continued with CAPT in 1994. The State of Connecticut touts the purposes of the tests are to monitor student progress, identify students for remediation, to promote accountability and equitability between/within school districts and to improve instruction/curriculum. Until 2001, the tests were not supposed to b e used as tool for promotion or graduation. In the 2001, school districts were mandated to create a specific set of criteria for graduation, with CAPT as one component but not the sole component (Connecticut Assessment Performance Test Overview 8). If the trend continues, Connecticut will have â€Å"... ...ment of Education. 2003. Connecticut Assessment Performance Test Program Overview. Dec. 2004 ct.us/public/der/s-t/testing/capt/2004_capt_program_overview.pdf>. Connecticut State Department of Education. 2003. Connecticut Mastery Test Program Overview. Dec. 2004 /s-t/testing/ cmt/cmt_program_overview_may_2004.pdf>. Connecticut State Department of Education. 2003. Strategic School Profile. Dec. 2004 . McMillan, James H. The Relationship Between Instructional ad Classroom Assessment Practices of Elementary Teachers and Student Scores on High-Stakes Test. Jan. 2003. Virginia Commonwealth University. Dec. 2004 storage_01/0000000b/80/28/04/d0.pdf>.

Air Transat Analysis Essay

Introduction: Air Transat is a Canadian airline based in Montreal, Quebec. It was founded in 1987, and is owned by Transat A.T. Inc. According to Air Transat’s website, their mission statement is: â€Å"Air Transat is Canada’s leading holiday travel airline. Every year, it carries some 3 million passengers to nearly 60 destinations in 25 countries aboard its fleet of Airbus wide-body jets. The company employs approximately 2,000 people. Air Transat is a business unit of Transat A.T. Inc., an integrated international tour operator with more than 60 destination countries and that distributes products in over 50 countries. Air Transat was named World’s Best Leisure Airline at the Skytrax annual World Airline Awards, held in July 2012.† â€Å"Transat A.T. Inc. is an integrated international tour operator with more than 60 destination countries and that distributes products in over 50 countries. A holiday travel specialist, Transat operates mainly in Canada and Europe, as well as in the Caribbean, Mexico and the Mediterranean Basin. Montreal-based Transat is also active in air transportation, destination services and distribution. (TSX: TRZ.B, TRZ.A)† Air Transat presents its products and services by stating that is a leading holiday travel airline that is owned and operated by Transat A.T. Inc. The types of customers served are international passengers within the 60 destinations that they operate in. Air Transat geographically covers 60 destinations in 25 countries. One of the ways Air Transat is distinguished from its competitors within the industry is by being give the world’s Best Leisure Airline two years ago in July 2012. Nothing has been mentioned about customer needs in their mission statement as well as they type of customers they are targeting. We could assume that Air  Transat is seeking holiday-oriented customer rather than business oriented customers for example. This mission statement shows no insight on how the firm will continue to compete with its competitors. According to Air Transat’s website, their vision statement is: â€Å"At Transat, we recognize the prime importance of the environment, host communities, cultural diversity, and our relationships with our employees, customers and partners. At Air Transat too†¦ Then, Air Transat is committed to reducing its ecological footprint, and has adopted an environmental policy.† This vision statement does not focus on the future they see in their vision with host communities, diversity, employees, customers, and partners. However, it focuses on the environment. It has done that by creating an environmental policy, which is committed to doing the following according to Air Transat’s website: 1. Complying with all applicable municipal, provincial, federal, and international legal requirements, exceeding compliance wherever practical and possible. 2. Certifying our environmental systems and performance to the highest standards, such as ISO14001, IENVa, LEED, ICI ON RECYCLE and Fly-360-Green. 3. Conserving natural resources, such as energy and water, and preventing pollution in our operations, buildings, and supply chains through source reduction, re-use, recycling and control. 4. Continuously improving our environmental performance by setting and reviewing objectives and targets, and by training and involving our employees and stakeholders whose activities have a significant environmental impact. 5. Collaborating with all of our key stakeholders (employees, suppliers, communities, governments and industry groups) regarding environmental, sustainable development, and corporate social responsibility initiatives and issues. Surprisingly, I did not find a strategic objectives statement on Air Transat’s website. There were no statements regarding how they will put their mission statement into action, or how their goals will be achieved.  However, there is a page that lists and summarizes all Air Transat’s awards, rewards, and recognition. PEST analysis: The definition of PEST analysis according to businessdictionary.com is: â€Å"A type of situation analysis in which political-legal (government stability, spending, taxation), economic (inflation, interest rates, unemployment), socio-cultural (demographics, education, income distribution), and technological (knowledge generation, conversion of discoveries into products, rates of obsolescence) factors are examined to chart an organization’s long-term plans.† POLITICAL ECONOMIC SOCIO-CULTURAL TECHNOLOGICAL Fuel taxation, and landing taxation Fear of terrorist attacks after 9/11. New European union regulations have led to higher levels of competition on European routes. Increase in the price of oil Increase in transportation costs Increase in disposable income due to rise in incomes and lower interest rates (people have more money to spend on leisure trips) Change in consumer behavior resulting from the aging population in Canada may affect the number of leisure trips taken Increased popularity in travelling abroad – Carbon dioxide emission – Emirates airlines launching double decker aircrafts (A380), serving 25 destinations – Wireless internet being launched in aircrafts – Frequent flyer programs The increase in the price of oil and the rate at which it is increasing is a global issue. For Air Transat, this means an increase in cost and expenditure. Since oil is essential in this industry, there is not much that Air Transat can do. The increase in the price of oil could cause force Air Transat to increase their prices for flight tickets. In more extreme cases, Air Transat may not be able to increase the prices for certain routes, and be forced to terminate their services to these routes. Air Transat could benefit from the change in consumer behavior resulting from the aging population in Canada by targeting the elderly population through advertising and promotions. For example, they could offer retirement packages, and certain promotions for specific destinations or at specific seasons of the year. Air Transat would need to conduct extensive market research about this matter to take into consideration that most retired people are on a fixed income or might not be healthy enough to fly etc. With the increased use of technology, wireless Internet is not only important for business traveler but also for leisure travelers. Even though it is not that common for aircrafts to offer wireless Internet during their flight, it being launched. Air Transat should consider offering this service, as it might be an attractive feature for many travelers. Porter’s Five Forces: According to investopedia.com, the definition of Porter’s Five forces is: â€Å"Named after Michael E. Porter, this model identifies and analyzes 5 competitive forces that shape every industry, and helps determine an industry’s weaknesses and strengths. 1. Competition in the industry 2. Potential of new entrants into industry 3. Power of suppliers 4. Power of customers 5. Threat of substitute products† The threat of new entry into the airline industry is very weak due to a few factors including very large capital required, major airports are highly congested, slow growth rates and with many reputable airlines already, brand loyalty may not be easy to establish due to the competition. This force is likely to remain weak. Competitive Rivalry is ranked as high because there are a high number of airlines operating both domestically and internationally with very competitive prices that Air Transat will need to constantly try to match. The fixed cost is very high such as the cost of oil, which cannot be controlled to a great extent. There is also a low product differentiation meaning that even though Air Transat is a leisure airline, there are still many other airlines that offer service to the same destinations at similar prices. Most airlines offer some type of frequent flyer program, which causes passengers who are members of these programs to be loyal to their airlines. This force could become even higher due to the increased competition. Bargaining power of suppliers is Moderate. Airlines are usually in a long-term contract with airline manufacturers, which also limit drastic increases in prices during that contract but because there are only two airline manufacturers; Boeing, and Airbus. They have a lot of power to make changes that Air Transat would be bound to accept. Labor my also be an issue because positions such as pilots, aerospace engineers, managers, and marketers may require high salaries and may not be easily found in the market. However, the salaries for labor in the airline industry are standardized over similar airlines. This force is likely to stay the same. Bargaining power of buyers is weak. Individual flyers, travel agencies, and online portals can all easily switch to different airlines due to low switching costs. However, the pool of customers is very large ranging from individual customers to large organizations. This force is likely to become weaker over time. Threat of substitutes is moderate within the airline industry because there are numerous airlines that offer service to the same destinations as Air Transat with similar prices, which does not limit the chance of customers switching to different airlines. However, that kind of standardization over the industry does not make other airlines more attractive than Air Transat. Threat of substitutes outside the industry is low because many destinations cannot be reached in a timely manner without flying, specially international ones. Flying is faster and safer than road, rail, or marine. I believe this force will become weaker over time. New Opportunities: Since Air Transat is well established in Canada, they have the chance to grow internationally beyond Europe. They can also take advantage of the current growth in the aging population in Canada by targeting that market and researching different ways to attract older customers. They could create a frequent flyer program specially designed for seniors. With Air Transat’s sold reputation, they could also have contracts with European organizations to provide them services. Air Transat could take advantages of the new developments in technology by providing wireless internet on their aircrafts and also by launching a new type of aircraft for European destinations such as the double decker plane that Emirates airlines launched. Threats: The main threat is the price of oil increasing is the highest cost for airlines now. A sudden spike in the price of oil could have negative impacts on Air Transat causing it to terminate service to one of their 60 destinations. There are other threats such as safety concerns due to the fear of terrorist attack, changes in government regulations and environmental issues. The airline/aviation industry overall is a great industry to be in for existing airlines, but a very hard one to get into for new airlines. Air Transat has a lot of potential to grow in the European market, and even  farther. Citations: Air Transat Environmental Policy. In Resp.Transat. Retrieved February 5, 2014, from http://www.resp.transat.com/_pdf/en/airtransat.environmental.policy.pdf?v=2. Emirates A30 News & Events. In Emirates. Retrieved February 5, 2014, from http://www.emirates.com/english/flying/our_fleet/emirates_a380/news_and_events/news_and_events.aspx External environment theory. In Business case studies. Retrieved February 5, 2014, from http://businesscasestudies.co.uk/business-theory/external-environment/pest-analysis.html#axzz2sW4YAx8I. Pest Analysis. In Business dictionary. Retrieved February 5, 2014, from http://www.businessdictionary.com/definition/PEST-analysis.html. Porter’s 5 Forces. In Investopedia. Retrieved Febuary 8, 2014, from http://www.investopedia.com/terms/p/porter.asp. Porter’s Five Forces. In Mind tools. Retrieved February 5, 2014, from http://www.mindtools.com/pages/article/newTMC_08.htm Porter’s Five Forces. In Sites google. Retrieved Febuary 8, 2014, from https://sites.google.com/site/admn703ai/the-team Profile. In Air Transat. Retrieved February 5, 2014, from http://www.airtransat.ca/en/About-us/Profile?ID=35&type=voyageur&tmpl=GEN.

Critical Review of Greasy Lake

When I began reading â€Å"Greasy Lake† by T. Coraghessan Boyle, I thought these boys were exhibiting typical behavior of young-adult men and their behavior led them to trouble. Boyle kept my interest by anticipation and disgust at the boys of the boy’s behavior in this story. The narrator, who is the main character of the story, often describes himself and his friends as â€Å"bad characters† and this becomes more convincing in the story. Boyle also used Greasy Lake at not only the setting for this story but also as a character. He described the lake as â€Å"fetid and murky, the mud banks glittering with broken glass and strewn with beer cans and the charred remains of bonfires. † Greasy Lake is used as a symbol for the youth culture itself in the story and is littered by alcohol, sex and violence. When the boys first came across the greasy man at the lake, their attitudes change for a moment, all three of them are scared. When they began to fight with the man, the narrator grabbed the tire iron out of fear. Once the three of them beat him up and knock him unconscious, I think this only increased their already arrogant attitudes. When they attempt to rape the greasy man’s lady companion, I think that shows how truly pathetic each of them are, acting like â€Å"deranged brothers†. In a very disturbing way, the boys were asserting a primal physical dominance over the woman. I think Boyle’s was sending a message that there are consequences for our actions. Even though kids tend to think they’re big and bad and have it all figured out, these once cocky boys quickly became horrified once they had to face the consequences of their actions. I personally enjoyed reading â€Å"Greasy Lake† very much. The language in the story Boyle used is crude and literal, but it goes with the theme of â€Å"badness† portrayed by his characters. Boyle emphasizes the corruption of the lake by using it as a not only the setting, but also as tool to compare the narrator and the youth of the time. In the beginning, the narrator is as corrupted as the lake; though born pure and â€Å"clear† he becomes tainted by the â€Å"beer† and wildness of his culture. By ending with the beaten narrator and his friend refusing drugs and driving home, Boyle left me with a sense of for the boys that they are not really â€Å"bad characters† after all. The narrator has realized the consequences of his actions, and that he can no longer act invincible.

Climate Change The Complex Issue of Global Warming

Climate Change The Complex Issue of Global Warming Introduction Global warming has emerged as one of the most important and complex global issues facing the international community. This phenomenon has led to climate change that has caused many negative impacts to the environment. The international community has come to a realization that it must pay greater attention to this problem. This paper will examine the complex issue of global warming by reviewing some important questions on the topic including the greenhouse effect, atmospheric carbon dioxide and the significant environment damages of increased carbon emissions.Advertising We will write a custom assessment sample on Climate Change: The Complex Issue of Global Warming specifically for you for only $16.05 $11/page Learn More Greenhouse Effect and CO2 Global warming has been largely attributed to the greenhouse effect. By definition, the greenhouse effect is the process through which the atmosphere absorbs infrared radiation emitted from the Earthâ₠¬â„¢s surface once it is heated directly by the sun during the day. This heat energy is then used to warm the planet. Greenhouse gases (GHGs) play an important role in controlling temperatures on the Earth. These gases fulfill this role by preventing all the sun’s radiation from escaping from the earth through convection (Jacobson 316). The GHGs selectively absorb radiation in the infrared region and then release this heat energy in all directions. By trapping some of the Sun’s heat energy, the greenhouse effect ensures that the temperatures remain high even when the sun is not shinning directly on the Earths surface. The natural greenhouse effect ensures that the Earths average near-surface air temperature is 150 (Jacobson 316). Without the greenhouse effect, the average temperature would be -150 and this is too cold to support most life. In addition to the natural greenhouse effect, human activities have also increased this effect. The greenhouse effect attributed to activities by human beings is referred to as the anthropogenic greenhouse effect and it has led to undesirable increases of global temperature on the Earth. There are a number of main GHGs responsible for the greenhouse effect. Water vapor is the main contributor to the greenhouse effect on the planet due to its ability to absorb infrared radiation. The second major contributor is carbon dioxide and this gas contributes between 10 and 25% of the greenhouse effect depending on the region (Jacobson 317). Methane gas, which occurs naturally or though the fermentation of organic matter, is the third major contributor of the greenhouse effect. The Ozone layer, which is a naturally occurring gas that is mostly concentrated in the stratosphere, is the fourth major naturally occurring greenhouse gas. Nitrous oxide, primarily produced from agricultural activities, is also an important greenhouse gas. The level of carbon dioxide in the atmosphere has experienced significant increase from the 280 parts per million (ppm) levels of 1860. The IPCC reports that the level of atmospheric carbon dioxide has been steadily increasing over the past few decades (1). The concentration in ppm in 1998 was 365 while in 2007 it had risen to 379ppm. Readings from the Mauna Loa Observatory indicate that the current rate is 393ppm (IPCC 1).Advertising Looking for assessment on environmental studies? Let's see if we can help you! Get your first paper with 15% OFF Learn More While natural atmospheric changes have contributed to an increase in the carbon dioxide level in the atmosphere, scientists agree that human activities have caused the greater increase (Dimitrov 801). Fossil fuel use has been the major cause of the increase in carbon dioxide levels. Fossil fuels have been used as the primary energy source for the industrialization process carried out from the last century. Cement production is also noted as a significant contributor to the carbon dioxide in the e nvironment. Carbon dioxide concentration has also risen due to the extensive deforestation that has taken place since 1860 (Dimitrov 802). Trees act as carbon sinks and reduce the level of CO2 in the atmosphere. Extensive deforestation has meant that the only a small amount of CO2 is absorbed by trees leading to the rise in atmospheric CO2. Environmental Damages of CO2 Emissions A number of major adverse effects to the environment are predicted if the CO2 emissions are not significantly reduced. The rise in CO2 will lead to increased temperatures on the Earth and this will increase the frequency of heat waves. Heat waves are devastating since they might lead to major fires that destroy natural habitats and even populated areas. Heat waves will also increase the demand on the available water resources (Fung and Lopez 119). The global warming attributed to carbon emissions will also increase flooding as the frequency of storms increases and sea levels rise due to the melting of ice at the Polar Regions. Fung and Lopez assert that climate change caused by CO2 will affect the quality of surface water. Some areas will experience increased flushing of nutrients and the increased storm intensity might lead to additional pollution of water (Fung and Lopez 119). The biodiversity on the Earth will also be negatively impacted by climate change. Some species will not be able to adapt the changing climate leading to their extinction. Analysis In my opinion, we do not need to wait for more evidence about the future of climate change before acting. The available evidence already strongly suggests that climate change is occurring due to the increase in greenhouse gases all over the world. Human activities are responsible for the extra CO2 emissions that have led to global warming.Advertising We will write a custom assessment sample on Climate Change: The Complex Issue of Global Warming specifically for you for only $16.05 $11/page Learn More The freq uency of the adverse environmental effects attributed to global warming has already increased. Failure to take action to mitigate climate change over the last few decades has led to an increase in the detrimental effects of global warming. While there is no single solution to fix the problem, reducing the greenhouse gas emissions to the environment is an effective method. The global community should start acting now in order to reduce carbon emissions and therefore mitigate the problems caused by climate change. Dimitrov, Radoslav. â€Å"Inside UN Climate Change Negotiations: The Copenhagen Conference.† Review of Policy Research 27.6 (2010): 795-821. Web. Fung, Fai and Lopez Ana. Modelling the Impact of Climate Change on Water Resources. NY: John Wiley Sons, 2011. Print. IPPC. Human and Natural Drivers of Climate Change. Jan. 2013. Web. Jacobson, Mark. Atmospheric Pollution: History, Science, and Regulation. Cambridge University Press, 2002. Print.

dead stars essays

dead stars essays The story is focused in the life of Alfredo Salazar, who is the son of Don Julian and the brother of Carmen, who is a lawyer and engaged to Esparanza to whom he is deeply in love with until he met Julia Salas who made him confused about his love for his fianc. Alfredo met Julia in Judge Del Valles house, a friend of his father, who is his sister-in-law. He was puzzled with her smile every time he addresses her and he was charmed with her speaking voice. The daily routine of Alfredo and his father every Sunday morning after the mass is to go to the judges house that made Alfredo and Julia closer and know each better. He forgot that for several Sundays, he had not waited for Esperanza to come out of the church and he was already beginning to lie about his neighboring stuff. This is the beginning of his attraction to Julia. Esperanza did not enter in the picture because she was not prone to unprovoked jealousies that made Alfredo entertain the feeling towards Julia. When Don Julian invited the judge to Tanda, where he has a coconut plantation, a house, and a beach, they had this goodbye conversation because Julias parents want her to spend Holy week with them. The line The end of the impossible dream! meaning they have to be apart soon, pro ves that Alfredo is really in love with her. The time when Alfredo felt a violent commotion in his heart that he did not feel for Esperanza when he saw her is already a big problem because he will be soon married. He was already lying with his feelings but he still keeps his word to Esperanza. At the end of chapter two, the conversation is cut when Esperanza went out weeping with what his fianc had said. This situation made Alfredo think of what must be done. In chapter three, the paragraph started about Alfredo going to Santa Cruz, where he would defend a case and how it would disturb him because Julias lake town is ...