Terrorism Essay Example | Topics and Well Written Essays - 250 words

Terrorism - Essay Example If one kills another human being due to self-defense—there is some purpose to it. However, if the attacker deliberately takes a live of someone to instill their radical views—that is ethically wrong. During terroristic attacks, human beings get treated as mere objects rather than creatures of life. Kant himself mentioned that people often induce terror â€Å"to treat them as ends in themselves and not simply as means to one's own ends.† Here it may seem complicated and puzzling, but Kant clearly here depicts the true agenda that is molded in human morality. Another reason why terrorism is not a justified means of achieving a particular is aim is due to the fact that it takes the lives of innocent citizens. One cannot diminish the fact that terrorism leads to innocent lives of victims. The victims in terrorist attacks are killed merely because they were present at that moment. The attack was not focused in military personnel or anyone, which makes the attack seem illogical. The victims are taken simply because they were present at that moment even though they were not associated Lastly, the use of terrorism is wrong because it uses violence as a way to justify the means of conducting violence. Terrorist attacks are no doubt a violation of human dignity.

Case Analysis Paper #2 Study Example | Topics and Well Written Essays - 750 words

Analysis Paper #2 - Case Study Example Therefore, based on my reasonable experience, I would support the innovation as an effective approach for heart surgery in view of extended application of minimally invasive techniques. The case study provides the progress, which Cardio Thoracic Systems have gone in the past two decades. From the analysis I have done of the progression of the systems, I would admit most innovators in this field have done impressive work. Despite that, not everything they did is perfect for some innovations have yielded to complications that are more severe. The CABG procedure was the initial approach used for heart surgery during that period (before 1996). This system proved effective in most cases though during surgery system would not give surgeons accessibility to some vessels, which they entailed to replace. Additionally, it resulted to severe complications such as trauma, complications associated with sternotomy and threats of chest infection among others. Moreover, the system was costly and resulted to a patient staying in hospital for so long (43days) after surgery (Chang 3). Certainly, these loopholes presented by the CABG system called for innovation of another system. Hence, this led to the contraption of Balloon Angioplasty and Stenting. The system, according to the case study, intrigued many surgeons for it was a less-invasive method as a remedy for coronary artery disease. Additionally, it did not require incision in the chest, thereby making it a perfect alternative for CABG system. Despite all the advantages, the innovators failed to control re-narrowing of the arteries (restenosis). Its worse state emerges after 6 months of surgery whereby restenosis would occur resulting to the formation of a similar plaque in the artery (Chang 4). Fortunately, physicians developed the stent, which significantly reduced restenosis occurrence though it did eliminate the

Case Study - Strategic Leadership Example | Topics and Well Written Essays - 1250 words - 2

- Strategic Leadership - Case Study Example Maytag always thrived on quality and remained customer-focused for its strategic predispositions. If a firm is operating along diverse business lines with a wide portfolio of products but not able to assure quality, even the broad line strategy fails because the proposition satisfies organization’s business and profit motives. On the contrary, if a firm operates in a single line of business and allows multiple communication streams to its customers, chances of its success are more likely on the grounds of focus on core competencies, clear vision and craving for customer loyalty by means of enhanced quality and performance every time. The strategy of Maytag matched this philosophy where its planning was aligned with supplier collaboration, involving other business entities in the decision making process of the company and a streamlined supply chain with monitoring and control at all levels. Such factors accounted for the unprecedented growth and superior performance of Maytag C orporation. Question 2 Earlier also, Maytag tried to carry on with the farm machinery and refrigeration business in conjunction with its laundry business. However, the move at that time was not accompanied by need of growth and expansion as was done during 1980s. Saturation of the laundry market compelled Maytag to revisit its decision of expanding its product line and foraying into related appliance market. Though refrigeration and home appliances were the two options available for Maytag to diversify, the latter seemed more lucrative as refrigeration had already been dropped off by Maytag. This might have made the former proposition cloudy and doubtful for Maytag. Secondly, the major rationale behind Maytag’s entering into the appliance market was to encash the availability of numerous technological advancement opportunities and bargaining power from suppliers prevailing. Maytag was already a reputed name in the market and had close connection with suppliers, better control of consumer psyche and brand image of a quality and price conscious company. These factors would definitely help Maytag replicate the legendary performance in the appliance sector as it had done in the laundry business. As such, with resources intact, Maytag should proceed to broaden its product line. In doing so, Maytag can provide greater number of connecting points to its customers with that of its business propositions and fill in the gaps with its value added products. Its collaborative relationships with suppliers and inter-functional departments will help in maximizing revenues and reducing costs through business excellence and experience. Question 3 Broad line strategy emerges after a company has performed well in serving a single market of the entire segment. In Maytag’s case, it is the Numero Uno leader in laundry segment of the home appliance market and its strategic competencies of superiority, customer-oriented philosophy, in-house production capabilities and co st economies are but obvious. Unlike laundry business, other appliance segments are characterized by technology, investment and changing consumer demands. In this light, Maytag has the alternative of either going for a licensing venture or a strategic alliance or acquisition. In the case of former, licensing will enable Maytag to concentrate on

Study of a leader in business Essay Example | Topics and Well Written Essays - 2500 words

Study of a leader in business - Essay Example ere a psychological profile that identifies a leader, and if so are there different psychological attributes that can identify a great leader If these traits can be somehow quantified, are there other qualities which are present in differing degrees that determine a business leader. ... he mood and temper of the people as well as the critical components inherent in the objectives Or are leadership qualities constant, displaying inherent characteristics that in differing degrees can be found in examples of leadership throughout history Is it something that a person is born with, inherits, or is learned Is there a psychological profile that identifies a leader, and if so are there different psychological attributes that can identify a great leader If these traits can be somehow quantified, are there other qualities which are present in differing degrees that determine a business leader. Is it style, intelligence, insight, a Midas touch, or elements of luck Could it be that the qualities that determine a successful business leader are attributes one is born with, or is it the ability to respond to the demands of the consistently changing business climate by finding solutions which enable one to work through vicissitudes and come out on top One common thread which is obvious in all great leaders, be they revered or scorned, is that they viewed the world, events, history, the present as well as the future in ways that were different from their contemporaries, and in such a manner that distinguished them in their era. What great leadership is, how it manifests itself in certain individuals is a subject which could entail considerable debate, thus the examination shall limit itself to one particular individual and determine if we can understand what and why this person has exhibited and demonstrated the attributes which cause us to view him in such a manner. This study shall look at Sir Richard Branson as an example of leadership in that he represents a contemporary individual who rose from modest means to become one of the world's most successful

Cameron International Corp Essay Example for Free

Cameron International Corp Essay The three major issues facing Cameron International (CAM) are acquisitions, environmental, and competition risk. Cameron International is primarily involved in the manufacture of petroleum production equipment, compression and power equipment to direct flows of oil and gas wells. Acquisitions The company is formerly known as Cooper Cameron Corporation. The company growth depends on the availability of natural resources. To be able to be competitive in the industry, it needs to analyze the existing processes and identify the best production method for harnessing oil and gas, and adjusting it manufacturing operations towards the identified need. The Company made significant investments in improving its services and products over the years. During 2004 to 2005, the company has acquired Petreco International and Dresser Flow Control Businesses. Also, â€Å"Recently CAM paid approximately $44 million to acquire DES Operations Limited, a Scotland-based supplier of production-enhancement technology, which will enhance the subsea operations within the Drilling and Production Systems segment† (value line). Subsea operations is the new direction to which the company is heading. In fact, the company is currently working on more than 15 major subsea projects using motors and other equipment made by an aerospace-industry contractor (Factiva Wall Street Journal). These projects will require a longer time, a large increase in financial scope, a need in substantial engineering, and it will also involve the application of existing technology to new environments or new technology (CAM 10K 2006 p. 7). Because this new operations are larger and more complex than traditional operations, the Company may not be prepared for meeting the expertise and technical requirements of the projects. Failure to meet client’s expectations does not only lead to loss in revenue, but also to loss of the significant financial investments committed by the company towards this innovation. The company has had both success and failures in this new endeavor. Subsea operations account for eight percent (8%) of the company’s revenue in 2006 (CAM 10K 2006 p. 7). According to Fortune magazine, the company has raised earnings by producing an array of subsea valves, wellheads and blowout protectors which are currently on high demand. The result is expected to make Camerons profits to climb thirty-nine percent (39%) this year. On the other hand the company experienced backlogs on the projects, amounting to as much as four hundred eight million dollars ($408 millions). Based on these figures, it is clear that the new operations of the Company can be lucrative and risky. As mentioned above, the new operations involve the following risks: not meeting client’s expectations, incurring delay, loss of revenue, loss of opportunity and loss of capital. Environmental Litigation The Company has a strong policy on environment sustainability and has implemented measures to ensure the quality, safety and reliability of its products. It utilizes an all electric sub-sea production system which is designed to reduce environmental contamination risks. It line of compression products offer greater efficiency and reduced emission levels. (Annual report 2006 p. 9) The company has conducted oil risk spills analysis through the OSRA models originally developed by Smith and company, which has been enhanced over the years and uses realistic data fields of winds and ocean currents in the GOM (OCS Report 2007). However, it may be noted that with Cameron’s policy to pursue an electric sub-sea production system, the risk of oil spills is reduced and the likelihood of it being involved in a major oil spill is reduced. In addition to this, the company has exerted efforts towards managing environmental risks involved in subsea operations by contributing in the development of a shut-off device called Environmental Safe Guard. This device has been proven successful in operation under 2000-m water (Simondin, et. al. 2005). Competition Risk Cameron International has maintained a track of growth in the oil industry, from 1833 up to the present. It currently manufactures 50 different brands of drilling and production systems. Growth can be expected to continue. As pointed out in the Company’s annual report (2006), sales of equipment like compression systems has registered a steady increase with the greatest share of revenues accruing from sales outside the United States. The Company has maintained an excellent revenue growth rate at thirty-nine point sixty-seven percent (39. 67%). It also has a net income growth rate of eighty-one point eighty-eight percent (81. 98%), while maintaining a good debt to equity ratio of forty-three point fifty-two percent (43. 2%). Debt to equity ratio is good compared to the industry average of 63% (Corn 2007). A comparison of the company’s ratios with others in the fields provides a clearer picture of its performance in the industry. The company’s touted revenue growth rate is ranked fifteenth (15th) in the industry and is extremely small compared to the leading company. Its long term growth rate is assessed as twenty-one percent (21%), also fifteenth in the industry. These ratios show us that the company’s performance is not the leading company in its industry but it does perform respectably compared with the other players. In its 10K, the company claims that it has a growing global market (CAM 10K p. 7). Some financial analysts agree with this statement. The CEO of Clear Indexes LLC and Clear Asset Management LLC claims that there is an increasing demand for oil in China and India and the Company is â€Å"ideally placed† in supplying the demand for increased production (Corn). However, because of the ties of Corn’s own company with CAM, this statement should not be taken at its face value. In the 30 April 2007 issue of Fortune, the company is only seventh in the industry with Halliburton ranking first. On a positive note, the company did climb up the Forbes 500 list with a present ranking of five hundred fifty-third (553rd) from last year’s six hundred eighty-fifth (685th). (Fortune 500 annual ranking) Based on the analysis above, the company’s performance is acceptable but not stellar. The changes made by the company towards subsea operations may be the wave of the future, providing not only a significant portion of the company’s revenues but also lowering environmental liability risks that are necessarily included in the company’s operations. The move, however, is not without its disadvantages. Subsea operations requires the commitment of large amounts of capital and expertise, expertise that the company has not fully mastered. The failure of the company in this endeavor will adversely affect the company’s growth for years to come.

UV Visible Spectrophotometry and Solution Absorption

UV Visible Spectrophotometry and Solution Absorption All molecules absorb light at certain wavelengths.   The absorption of light by a solution may be used to determine the concentration of a solute or a mixture of solutes in solution. The Beer-Lambert law refers to the linear relationship between absorbance (A), and concentration (C) of an absorbing species. According to the two fundamental principals that govern the absorption of light by a solution, the absorption of light passing through a solution is exponentially related to the number of molecules of the absorbing solute, and thus the solute concentration, and the length of the absorbing solution. These principals are combined, and when working in concentration units of molarity, the Beer-Lambert law is as follows: For part A of this experiment the ÃŽÂ µ value at the à ¯Ã‚ Ã‚ ¬max for Vitamin B12 was determined by measuring the absorbance of a known concentration of Vitamin B12 and by using the above Beer-Lambert formula. Vitamin B12 is a compound of significant nutritional and clinical importance. Assaying and understanding absorption of vitamin B12 helps with diagnosis of defects in humans that can lead to hematological and neurological complications. For part B of this experiment chlorophyll concentration of a leaf extract was calculated. In context to the experiment, eukaryotic green plants and algae, and prokaryotic cyanobacteria contain chloroplasts which have several pigment types, the most abundant of these being chlorophyll a. Green and blue-green coloured chlorophyll a absorbs maximum light energy at the photosynthetic reaction centre (during the light reaction of photosynthesis) at wavelengths in the blue (à ¯Ã‚ Ã‚ ¬max 420 nm) and red (à ¯Ã‚ Ã‚ ¬max 663 nm ) regions of the visible spectrum. The green-yellow coloured chlorophyll b is also present in all green plants and has an absorption spectrum (red à ¯Ã‚ Ã‚ ¬max 645 nm and blue à ¯Ã‚ Ã‚ ¬max 435 nm) slightly different from chlorophyll a. Normally the ratio of chlorophyll a:b is 3:1. As with most biological molecules chlorophyll is synthesised by biochemical pathways, and one intermediate molecule in the synthesis pathway is protochlorophyllide (à ¯Ã‚ Ã‚ ¬max 626 nm) which is eventually converted into chlorophylls a and b. The amounts of chlorophyll and other pigments in plants can be determined using a spectrophotometer following extraction with various organic solvents. Based on the Beer-Lambert Law and a knowledge of absorption coefficients of pigments dissolved in particular solvents, equations have been derived to directly determine the concentrations of common pigments following extraction by measurement of the absorbance (A) of the solution at a given wavelength (à ¯Ã‚ Ã‚ ¬max) in a cuvette.   For part 3 of the experiment, protein concentration was determined by use of UV and Visible spectrophotometry, and Construction of a Standard Graph.   The estimation of protein concentration is an important measurement in biological sciences. For pure samples of proteins absorbance measurements at 280 nm can be used to directly determine protein concentration; all proteins absorb in this region of the spectrum due to their aromatic amino acid residues (tyrosine, tryptophan and phenylalanine).   For protein mixtures, very dilute solutions, or for proteins with interfering chromophores, colourimetric methods must be used. These involve subjecting a pure protein standard of known concentration to a colourimetric reaction, and measuring the absorbance of the coloured end product. The sample protein of unknown concentration is subject to the same colourimetric reaction. The concentration of the sample protein can be read directly from a standard curve.   The Lowry assay involves the production of a blue (phosphomolybdate-tungstate) chromophore, from a copper-protein complex.   In this part of the practical, Lowry and direct absorbance methods were compared for the determination of the concentration of lysozyme in solution. The first of the methods makes use of a ÃŽÂ »max in the UV part of the spectrum and the other in the visible part of the spectrum.   Aims   To competently use a spectrophotometer and accociated cuvettes (cells) To relate absorbance of a solution to concentration using the Beer-Lambert law To determine the molar absorption (extinction) coefficient of vitamin B12 and compare its value with that from a standard reference table. To calculate the chlorophyll concentration in a leaf extract using absorbance values at defined wavelengths and a formula applicable to the solvent extraction medium. To measure protein concentration using direct absorbance and, following construction of a calibration curve, by a colourimetric method. Methods Part A To begin the experiment, the spectrophotomer was calibrated in accordance to the information given in the instrumentation booklet (p. 35, viii). Using distilled water in a plastic cuvette at a wavelength of 550 nm the spectrometer was then placed on zero. Using the provided Aqueous Vitamin B12 (cyanocobalamin) solution at a stock concentration of 0.15 g dm-3 (relative molecular mass = 1.355 x 103 i.e. 1,355 Daltons ), The A value was measured and recorded at ÃŽÂ »max at 550 nm. The A value was Placed on the results sheet. The vitamin B12 solution concentration was converted from g dm -3 to mol dm-3 and then using this data the ÃŽÂ µ value for Vitamin B12 was calculated (see calculations). Part B For the second part of the experiment a sample of pigments extracted from dandelion leaves homogenized in an aqueous acetone extraction medium (80%) was provided. A clear pigment solution was needed for the test and so a check was carried out to ensure that there was no plant debris that may have interfered with light passage before the absorbance of the sample was measured. Using a Pasteur pipette, the clear extract was transferred into a clean quartz cuvette. The spectrophotometer was placed on zero using a quartz cuvette filled with an aqueous acetone mixture (80%) set at a à ¯Ã‚ Ã‚ ¬max wavelength of 663 nm and the absorbance of the pigment solution was measured at 663 nm. The spectrophotometer was again placed on zero using the acetone solution (80%), however it was set at a à ¯Ã‚ Ã‚ ¬max wavelength of 645 nm before the absorbance of the pigment solution was measured. The spectrometer was placed on zero for a third time and set at à ¯Ã‚ Ã‚ ¬max wavelength of 626 nm. The absorbance of the pigment solution was again measured and all three sets of data were recorded. Part C (a) Direct absorbance A quartz cuvette was filled to the level with H20 and used as a standard to set the spectrophotometer at zero. Using another quartz cuvette the A value of the lysozyme solution of unknown concentration was measured at a ÃŽÂ »max of 280 nm. The value obtained was recorded. Having measured the A280 value of the unknown lysozyme sample, the concentration of lysozyme was calculated taking into consideration that ÃŽÂ µ280 of lysozyme = 3.65 x 104 dm3 mol-1 cm-1 and using the Beer-Lambert Law. The concentration of the lysozyme sample was then changed from mol dm-3 to à ¯Ã‚ Ã‚ ­gcm-3. (b) Colourimetric Lowry Assay (Preparation and Use of a Standard Curve) Using a stock reference standard BSA solution containing 250 à ¯Ã‚ Ã‚ ­g cm-3 protein, a series of dilutions of the stock were prepared accurately, as per the table below: Tube No: 1 2 3 4 5 6 7 8 BSA stock (cm3) 1.0 1.5 2.0 2.5 3.0 3.5 4.0 5.0 H2O (cm3) 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.0 Note that the dilution factors for each tube were used to enable calculations for final concentrations of BSA in tubes 1- 8 inclusive (see calculations). These values are then used to plot a standard curve. Standard solution (1.0 cm3) prepared in the above table was placed in 8 clean, dry test tubes. unknown lysozome sample (1cm3) was placed into test tube 9, and H2O (1.0 cm3) was placed in test tube 10 as a water/reagent blank control. A solution of Lowry C (alkaline copper reagent) was made up by mixing Lowry B1 (0.5 cm3) with Lowry B2 (0.5 cm3) and lowry A (50 cm3). A solution of lowry D (Folin Ciocalteus phenol reagent) was then made up by diluting Folin reagent (5 cm3) with distilled H2O (10 cm3). Lowry C reagent (5.0 cm3) was added to all ten test tubes. The solution was mixed and left for 10 minutes. Lowry D reagent (1.0 cm3 ) was then added to each test tube and mixed well. All tubes were left for 30 minutes at standard temperature (37oc) for reaction and colour development to occur, after which time the test tube contents were thoroughly mixed. For test tubes 1-9, the A value at à ¯Ã‚ Ã‚ ¬max 750 nm was measured. Test tube 10 was not measured as it was used as a H2O/reagent blank to zero the spectrophotometer. Calculations Part A Due to the fact that a known amount of solute has to be dissolved in a given volume of solvent to obtain a solution of the required concentration, the number of moles of the solid can be calculated from the following equation: n = Mass of solute Relative molecular mass To convert the Aqueous Vitamin B12 (cyanocobalamin) solution from g dm -3 to mol dm-3 one must consider that the stock concentration is 0.15 g dm-3, and the relative molecular mass of Vitamin B12 is 1.355 x 103 . 0.15 / 1.355 x 103 = 0.11 x 103 To find the ÃŽÂ µ value (wavelength absorption coefficient) of vitamin B12 the Beer-Lambert law must be applied: A= 0.827 L= 1cm C= 0.11 x 103 dm3 mol-1 cm-1 at ÃŽÂ »max of 550 nm ÃŽÂ µ = unknown As A= ÃŽÂ µLC, the equation can be rearranged as follows to make ÃŽÂ µ the subject: ÃŽÂ µ = A/C Therefore: ÃŽÂ µ = 0.827/0.11 x 103 = 7.51 x 103 Part B Chlorophyll Concentration determination The following formula was used to calculate the concentration of pigment in the extract. Chlorophyll a = 12.67A663 2.65A645 0.29A626 Chlorophyll b = 23.6A645 4.23A663 0.33A626 Protochlorophyllide = 29.6A626 3.99A663 6.76A645 The absorbance (A) is the respective wavelengths obtained directly from the spectrophotometer with the use of a 1cm light path length cuvette. Chlorophyll a = (12.67 x 0.934) (2.65 x 0.390) (0.29 x 0.321) = 10.71 ug cm-3. Chlorophyll b = (23.6 x 0.934) (4.23 x 0.390) (0.33 x 0.321) = 20.29 ug cm-3. Protochlorophyllide = (29.6 x 0.934) (3.99 x 0.390) (6.76 x 0.321) = 23.92 ug cm-3. Part C (a) Direct absorbance Concentration of lysozyme was calculated using the Beer-Lambert law as follows: A = 0.177 ÃŽÂ µ = 3.65 x 104 dm3 mol-1 cm -1 L = 1cm C = Unknown The Beer-Lambert law can be rearranged, making C the subject of the equation. Therefore the value of C can be calculated as: C = A / ÃŽÂ µ C = 0.177 / 3.65 x 104 = 4.84 x 10-6 mol dm-3   The concentration of the lysozyme sample was then changed from mol dm-3 to à ¯Ã‚ Ã‚ ­gcm-3 Using the following formula: n= M / RMM 14.31 x 103 x 4.84 x 10-6 = 0.069g To change this from g to à ¯Ã‚ Ã‚ ­g it must be multiplied by 1000,000 as follows: 0.069 x 1000,000 = 69000 To then change this calculation from dm-3 to cm-3 it must be divided by 1000 as follows: 69000 / 1000 = 69 à ¯Ã‚ Ã‚ ­g cm-3 (b). Preparation and Use of a Standard Curve for Lowry Assay: Concentration (à ¯Ã‚ Ã‚ ­g cm-3) was calculated using the below figures: Tube No: 1 2 3 4 5 6 7 8 BSA stock (cm3) 1.0 1.5 2.0 2.5 3.0 3.5 4.0 5.0 H2O (cm3) 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.0 Test tube 1. BSA stock (cm3) = 1.0 H2O (cm3) = 4.0 1.0 + 4.0 = 5 1.0 / 5 = 0.2 0.2 x 250 = 50 Test tube 2. BSA stock (cm3) = 1.5 H2O (cm3) = 3.5 1.5 + 3.5 = 5 1.5/5 = 0.3 0.3 x 250 = 75 Test tube 3. BSA stock (cm3) = 2.0 H2O (cm3) = 3.0 2.0 + 3.0 = 5 2.0 / 5 = 0.4 0.4 x 250 = 100 Test tube 4. BSA stock (cm3) = 2.5 H2O (cm3) = 2.5 2.5 + 2.5 = 5 2.5 / 5 = 0.5 0.5 x 250 = 125 Test tube 5. BSA stock (cm3) = 3.0 H2O (cm3) = 2.0 3.0 + 2.0 = 5 4.0 / 5 = 0.6 0.6 x 250 = 150 Test tube 6. BSA stock (cm3) = 3.5 H2O (cm3) = 1.5 3.5 + 1.5 = 5 3.5 / 5 = 0.7 0.7 x 250 = 175 Test tube 7. BSA stock (cm3) = 4.0 H2O (cm3) = 1.0 4.0 + 1.0 = 5 5.0 / 5 = 0.8 0.8 x 250 = 200 Test tube 8. BSA stock (cm3) = 5.0 H2O (cm3) = 0.0 5.0 + 0.0 = 5 5.0 / 5 = 1 1 x 250 = 250 Results 1. Molar absorption coefficient of vitamin B12: Absorbance reading at ÃŽÂ »max of 550nm (A550nm) 0.827 2. Absorption Pigment type A Value Absorption Concentration Chlorophyll a A663nm 0.934 10.71 Chlorophyll b A645nm 0.390 20.29 Protochlorophyllide A626nm 0.321 23.92 Fig. 1. a table showing the A value of three different pigment types found in a leaf extraction, and the measured absorbance and calculated concentration of each. 3. Lysozyme Concentration Determination: (a) Direct absorbance reading at ÃŽÂ »max of 280 nm (A280nm) 0.177 (b). Preparation and Use of a Standard Curve for Lowry Assay: Discussion Part A A). Using the data collected, the experimental the ÃŽÂ µ value (dm3 mol-1 cm-1) calculated during this experiment was compared to that of an ÃŽÂ µ value obtained from  commercial standard references data. ÃŽÂ »(nm) ÃŽÂ µ(dm3 mol-1 cm-1) Standard ÃŽÂ µ value 550nm 8.55 x 103 Experimental ÃŽÂ µ value 550nm 7.51 x 103 Fig. 4. a table to show a comparison between standard and experimental ÃŽÂ µ values. As the above data indicates, the experimental ÃŽÂ µ value obtained during this experiment differs from that of the standard ÃŽÂ µ value. B). Other than human and experimental errors, one possibility that could explain the differences in the ÃŽÂ µ values is that to a certain degree different spectrophotometers in the laboratory give different readings. If the standard ÃŽÂ µ value was recorded using a different spectrophotometer this could cause anomalies within the results. A second possibility is that the solution used to find the experimental ÃŽÂ µ value was not at a stock concentration of exactly 0.15 g. This would affect the calculations and hence a different result would be obtained to that of the standard ÃŽÂ µ value. Part B 1(a).The % of chlorophyll a, chlorophyll b and protochlorophyllide in the leaf extract can be calculated in the following way: chlorophyll a concentration = 10.71 ug cm-3 chlorophyll b concentration = 20.29 ug cm-3 protochlorophyllide concentration = 23.92 ug cm-3 10.71 + 20.29 + 23.92 = 54.92 Percentage of chlorophyll a = 10.71/54.92 x 100 = 19.5% Percentage of chlorophyll b = 20.29/54.92 x 100 = 36.9% Percentage of protochlorophyllide = 23.92/54.92 x100 = 43.6% 1(b).It can be seen from the above percentages that 43.6% of the leaf extract is composed of protochlorophyllide. This is the largest percentage present within the leaf extract and therefore it can be considered as the predominant pigment type. 2(a). The percentages obtained can also be used to calculate the ratio of chlorophyll a:b in the leaf extract. In the case of this experiment the ratio of chlorophyll a:b in the leaf extract was 2:1. 2(b). The determined value to be expected when calculating the ratio of chlorophyll a:b in the leaf extract was 3:1. One would expect this as there are three pigments in the leaf extract, that ideally should contribute evenly. However, The results from this experiment vary from the standard data as they show a ratio of 2:1 between chlorophyll a and b. The most probable reason for this variation is not due to anomalies in results or calculations, but the fact that not all leaf extracts will contain the standard amount of pigments. In some cases pigments may be present in a higher percentage of one than the other, as is this experiment where protochlorophyllide was the predominant pigment type. 3). Although the above ratio is only dealing with percentages of chlorophyll a and b present in the leaf extract, one must consider that the presence of protochlorophyllide must be allowed for in the formulae and hence in the calculations. This is because there are three pigment types involved in the leaf extract and so one must consider that the ratio of the whole leaf extract is actually 3:2:1 where the ratio of chlorophyll a:b is 2:1. 4). The use of a formula related to a given extraction solvent is a convenient method for determining the concentration of chlorophyll. However, making use of the Beer-Lambert Law the concentration of chlorophyll could also be found by preparation and use of a standard curve. Part C Determination of Protein Concentration by UV and Visible Spectrophotometry, Construction of a Standard Graph Proteins have aromatic side chains such as tryptophan tyrosine and phenylalanine which absorb light at 280nm. The Lowry method is based upon a combination of the biuret method and the oxidation of tyrosine and tryptophan residues. The biuret reaction involves the binding of Cu2+ under alkaline conditions to nitrogen found in the peptide bonds of proteins. This reaction gives off a deep blue colour. The folin reagent contains phosphomolybdotungstate acids which are reduced to tyrosine, tryptophan and polar amino acids. This creates an intense blue-green colour. (a). The data collected was used to create a graph, plotting a standard curve of A (Y axis) against BSA concentration (X axis) in à ¯Ã‚ Ã‚ ­g cm-3 (See fig.3). This graph, shown in fig.3., was effectively constructed assuming that the relationship between absorbance (A) and concentration (C) must be linear to satisfy the Beer-Lambert law. However, the Beer-Lambert relationship between absorption and concentration deviates from lineariy in the case of more concentrated solutions. Linear BSA standard curves are only obtained at low protein concentration and so therefore to decrease possible anomilies in the results, timing of both residue addition and mixing were crucial. Using the A value from test tube 9, it was possible to use the graph to determine the concentration of the unknown lysozyme sample in à ¯Ã‚ Ã‚ ­g cm-3. Results from the graph show that. (b) By examining the lysozyme concentration results obtained (in à ¯Ã‚ Ã‚ ­g cm-3), it is possible to make a comparison between the results for the colourimetric assay and the direct absorption technique. Results show that Lysozyme concentration for colormetric assay were (m/rmm thing) Lysozyme concentration results for direct absorbance technique were..(graph) These results are same/different. Due to the fact that different proteins have widely varying characteristics, there may be considerable errors within the data. With the colormetric assay any non-protein component of the solution that absorbs UV light could interfere with the assay, resulting in the production of colour by substances other than the analyte of interest. This would cause the results to vary from that of the direct absorbance technique. (c). For this experiment three different methods were used for concentration determination, each of which had different strengths and weaknesses with respect to their sensitivity, accuracy and convenience. The first of these methods was the use of a formula, to determine chlorophyll concentration. Using a formula gives a very accurate theoretical result but it is not particularly convenient as for calculations to be correct it can take a great deal of time and effort. Obviously with such calculations, they are not sensitive as there is no outside interference to affect results. Direct absorbance is not as sensitive as the colormetric method, but as it requires the use of a spectrophotometer, it is an accurate assay method. This also makes the method relatively convenient for determining the concentration of lysozyme present in a given solution as changes in absorbance of the lysozyme could be clearly seen and recorded using the spectrophotometer at a particular wavelength. The colourimetric method was also used to determine the concentration of lysozyme during this experiment. One benefit of using the Colormetric method is that it is extremely sensitive (down to a protein content of 20ug ml-1) and it is also moderately constant from one protein to another. However, with respect to accuracy, this method is subject to interference from a wide range of non-protein substances including many organic buffers. The choice of an appropriate standard is important as the intesnsity of colour produced for a particular protein is dependant on the number of aromatic proteins. As different proteins have a different number of aromatic residues, the Lowry assay is considered more of a qualitative measure of protein content more than quantitative method of determining protein concentraion. This method is not as convenient as the direct absorbance method in that it takes a lot longer to perform and there is a higher frequency of anomalies that must be accounted for. (d). The measurement of protein levels is of significant diagnostic importance in both clinical and veterinary medicine. In clinical medicine there are a wide variety of biomedical tests involving the measurement of protein levels, such as the detection of abnormal protein levels in cerebrospinal fluid (CSF), suggesting that there is an abnormal process occurring in the central nervous system. Protein levels in urine samples are tested to monitor and evaluate kidney function, and essentially to detect and diagnose kidney damage and disease at and early stage. Serum protein tests are also important as they concern measurement of protein levels of albumin and globulin in the blood. Such tests are also important in veterinary medicine. According to reports from Cornell universities college of veterinary medicine, protein tests have been developed to accurately indicate canine liver failure caused by the toxin aflatoxin. (e). Another way in which protein concentration can be measured, other than by the use of a formula or a spectrophotometer is gel electrophoreses. This technique uses charged protein molecules to separate physical properties, as they are forced through a gel by an electrical current.

Advantage Of Star Topology

Advantage Of Star Topology Star Topology: In a typical star topology, all computers/ stations are connected to a central device, usually a switch. They are connected to this central device via cable segments. Such cable segments are Unshielded Twisted Pair (UTP) and Shielded Twisted Pair, as well as, fibre optic cabling. http://www.inetdaemon.com/img/topology_star.gif Advantage of star topology: With the star topology, if one cable of device goes down, the rest of the network is not affected (fault tolerance). Disadvantage of star topology: However, because management of communication is centralized, if the main switch or hub goes down the whole network goes down. Extended Star Topology: As the name implies, it is a bit more advanced than the typical star topology. In this topology, there is also a central device, usually a switch, in the middle of the network. However, instead of computers being directly connected to this central switch, other switches or hubs are connected to its ports. Computers and other peripherals are then connected to these switches or hubs, forming other stars; hence an extended star is the final result. http://t0.gstatic.com/images?q=tbn:O2WYXsb8K_NPNM:http://upload.wikimedia.org/wikipedia/ro/b/b5/Extended_star_topology.png Advantage of extended star topology: As a result of there being a central switch, it is easy to locate and troubleshoot any problematic areas. Disadvantage of extended star topology: Again, because of the use of the centralized switch, once the switch goes down it creates problems for the entire network. Ring Topology: In this particular network topology, each computer/ station is directly connected to the next one in line and ends at the very first computer/ station, resulting in a circular formation/ arrangement of the cables. Each computer has the responsibility of retransmitting communication messages. The communication messages all travel in one direction and as a result of having no end in the circular formation, there is no real need for termination. http://www.inetdaemon.com/img/topology_ring.gif Advantage of ring topology: Due to the topologys structure, there is no need for terminators. Disadvantage of ring topology: Any break or fault in the cable can disrupt communications. Bus/ Linear-Bus Topology: This structure utilizes a single cable segment which connects all the computers in a single straight line. All computers in this topology share this single cable segment and as a result a terminator is needed. This is due to the fact that the signals need to be absorbed as they reach the end of the bus in order to free the network for fresh and newer communications. http://www.inetdaemon.com/img/topology_bus.png Advantage of bus topology: This is an inexpensive topology to install. Disadvantage of bus topology: With all the devices sharing the same backbone cable, communication speeds are lowered. Tree Topology: Logically, this is an extension to the less complex bus topology. www.networkdictionary.com states that The transmission medium is a branching cable with no closed loops. The tree layout begins at a point called the head-end, where one or more cables start, and each of these may have branches. The branches in turn may have additional branches to allow quite complex layouts. It is often referred to as the star- bus topology. Available from: www.networkdictionary.com/networking/lanat.php [Date accessed: October 24th 2009] graphics/04fig11.gif Advantage of tree topology: This topology allows point to point wiring for individual sectors. Disadvantage of tree topology: A break in the main backbone cable will affect the entire network. Mesh Topology: In the mesh topology, each device in a network is connected to every other device in the particular network. The mesh topology is typically used to connect several LANs together to create a WAN (it is more WAN based technology) e.g. the internet is a perfect example of a mesh topology. http://www.google.tt/images?q=tbn:MKaJ7Z8cc3BUJM::www.erealmedia.com/cms102/uploads/NetworkingPrinciples/Chapter1/1_23_MeshTopology.jpgt=1h=196w=176usg=__QGrcgQACaPCnhXDPW-hE9X5a-Rw= Advantage of mesh topology: Due to the fact that all devices are interconnected to each other, there are various alternate routes, which improve fault tolerance. Disadvantage of mesh topology: Managing and troubleshooting this architecture is very difficult, complex and expensive. 1.2.0 Advantages and Disadvantages of LAN media The media used in a typical LAN (Local Area Network) are Coaxial cables, Twisted-pair cables (Unshielded and shielded twisted pair) and Fibre Optic cables. 1.2.1 Advantages of Coaxial cables: Appropriate for Broadband system: Coaxial cables possess adequate ranges of frequency that can support several network channels and as a result of such capability, allows for much greater throughput. Better bandwidth: Compared to twisted pair cables, coaxial offers a better bandwidth system wide, as well as, better bandwidth for each network channel. As a result of this, there is support for a diverse range of service. Network functionalities such as data, voice, video and even multimedia can profit from the improved capacity. An even better spacing between amplifiers: Due to the cable shielding possessed by coaxial, there is a reduction in noise and crosstalk, thereby allowing amplifiers to be spaced farther apart. Lower error rate: Noise resistance is enhanced because the inner conductor is in a wire mesh and coaxial has lesser error rates. Better channel capacity: Extensive capacity is offered from each of the several channels. Disadvantages of Coaxial cables: Installation can be expensive Prone to damage from lightning strikes: People residing in areas, in which lightning strikes frequently occur, must be cautious. If the lightning is conducted by a coaxial, chances are that the equipment connected to the end of that particular coaxial, may be fried. Noise: The path of return has noise exertion and the end apparatus requires additional aptitude to deal with error control. Deployment architecture problems: The bus topology in which the coaxial is set up is vulnerable to noise, clogging and security can be jeopardized. Bidirectional (two-way) upgrade is required: In countries where there is a history of cable television, these systems are designed and built for broadcasting, not interactive communications. For a service provider to offer a subscriber any form of two-way communication services, the current network system needs to be upgraded to a Bidirectional system. 1.2.2 Advantages of Twisted pair cables: The cost of installing twisted pair on site is low High availability: Billions telephone subscriber lines established on twisted-pair have been set up and because it is already in the ground, the telecommunication companies will use it. Low cost for local moves, additions and changes in places: Individuals can swap twisted-pair terminating in a modular plug with another jack. This can be done without a service technician, given that the wiring is already in place. Disadvantages of Twisted pair cables: Frequency spectrum is limited: The total serviceable frequency spectrum of is about 1MHz. High error rates: It is extremely susceptible to interferences in signal communications, caused by EMI (Electromagnetic Interference) or RFI (Radio Frequency Interference). Data rates are limited: The longer the distance the signal travels over cable, the lower the data rate will be. At 30 feet (100m), twisted-pair is capable of carrying 100Mbps. At 3.5 miles (5.5km), the data rate can drop to 2Mbps or possibly less. Short distances are required between repeaters. 1.2.3 Advantages of Fibre Optic cables: Fibre optic cables have higher bandwidth compared to other mediums. It is impossible to tap into fibre optic cables. This makes them much more secure compared to other mediums. One can add equipment to provide extra capability over a fibre without having to change it. No electricity passes through the cables what so ever, and as a result they do not conduct lightning strikes They are light weight Disadvantages of Fibre Optic cables: They are more fragile compared to other mediums. Installation of the cables is quite expensive. Termination of fibre optic cables is quite complex and requires special tools 1.3.0 Recommendation After much investigation of the various LAN topologies and media, I have gathered comprehensive information and have come to a conclusion which topology and media type should be used. With respects to the LAN topology, I strongly recommend that the extended star topology be implemented. The extended star offers fault tolerance in that, if failure in one cable or device occurs, it doesnt pose as a threat to the rest of the network. If at all there are problems with particular cables or devices, the task of locating them is quite easy. Management is centralized due to the use of the centralized switch and it is easy to add devices as the network expands. Also, it can be upgraded for faster speeds and better performance, not to mention that it is the most widely used, so much support is available. Such a LAN topology proves to be quite costly but with all its benefits it is worth the expense. With regards to network media, if the extended star LAN topology is to be in use, the unshielded twisted-pair cables are a suitable medium. The installation costs are low and in addition, any changes or additions are cheaper compared to other media types. Furthermore, telecommunication companies will use subscriber lines that already exist, so there is no need for additional costs of running lines. Bibliography K. Wilson Jarrett and L. Goleniewski, (Oct. 12th, 2007), Traditional Transmission Media for Networking and Telecommunications. (Coaxial Cable) www.informit.com/articles/article.aspx?p=683070seqNum=2# [Date accessed: October 24th 2009] K. Wilson Jarrett and L. Goleniewski, (Oct. 12th, 2007), Traditional Transmission Media for Networking and Telecommunications. (Twisted-Pair) http://www.informit.com/articles/article.aspx?p=683070 [Date accessed: October 24th 2009] K. Wilson Jarrett and L. Goleniewski, (Oct. 12th, 2007), Traditional Transmission Media for Networking and Telecommunications. (Fibre Optics) http://www.informit.com/articles/article.aspx?p=683070seqNum=5 [Date accessed: October 24th 2009] Network Dictionary, (2004-2010), LAN Architectures and Topologies: Bus, Star, Ring and Tree. www.networkdictionary.com/networking/lanat.php [Date accessed: October 24th 2009] Task 2 a) 2.1.0 Internet services required 2.1.1 E mail: The abbreviation for electronic mail; this is a system of exchanging information/ messages digitally via the internet. 2.1.2 Voice/VoIP: The abbreviation for Voice Over internet Protocol; this is a system used in telecommunications for the transmission of voice traffic/phone calls over any network based on IP (Internet Protocol) e.g. the internet. 2.1.3 FTP: The abbreviation for File Transfer Protocol; this is the TCP/IP standard used for the transferring of files from one computer to another. 2.1.4 TELNET: This is the TCP/IP standard used for remote terminal services. It allows users at one site to transparently interact with a remote system or network at another site, whilst appearing as a local terminal. 2.1.5 Video communication: J. Wilcox Pg.3 states, Video communication is real-time exchange of digitized video images and sounds between conference participants at two or more separate sites. 2.2.0 Required connection speeds 2.3.1 With regards to Audio and Data communication, 64 Kbits/s is sufficient enough for use of this service. In the case of Video communication, bandwidth of 2Mbits/s or more may be required for proper transmission. Furthermore, www.whichvoip.com states VoIP requires anywhere from about 24Kbits/s to about 90Kbits/s. Overall, once serviced with an appropriate broadband package, these requirements will be addressed. Available from: http://www.whichvoip.com/voip/speed_test/ppspeed.html [Date accessed: October 27th 2009] 2.3.0 Internet Service Providers (ISPs) In Trinidad, there are various internet service providers from which one can subscribe for broadband services. Blink, Flow, and Lisa Communications are such ISPs. 2.3.1 Blink Packages 2.3.2 Flow Packages 2.3.3 Lisa communications 2.4.0 Recommendation After investigations on ISPs in Trinidad regarding their services and prices offered, I have seen favourable packages with one particular ISP, Flow. Flow offers its customers bandwidth speeds ranging from 512k/1Mbps to 3Mbps/9Mbps. Also they provide free static IP addresses and email addresses, and the number of IP email addresses one receives depends on the package one chooses. The packages are as follows: