The Eye And Laser Eye Surgery Essay -- essays research papers

A Functioning Eye (Emmetropia) The eye is the organ of sight. It is used in almost everything we do, from playing sport to reading. A normal and well functioning eye can focus objects and images, both near and far, perceive depth and adapt to changes in light. The perception of depth is due to having two separate eyes creating two separate images, while the ability to adapt to light change is attributed to the iris and the dilator muscles. However these two aspects of the eye are not involved in laser eye surgery and will not be discussed in reference. The focusing of objects and images is very much part of laser eye surgery. In order for a clear visual image to be formed the image must come to a point on the retina. Light rays do not normally travel toward each other, usually the light rays either travel outwards or almost parallel, for this reason the light rays must be refracted. The cornea is the primary place of refraction, the â€Å"bent† light rays then travel through the aqueous humor and the pupil to the lens. Here the light is one again refracted even closer together, the light then goes through the vitreous humor and is projected onto the retina. The focus of the lens should be aimed at the fovea centralis (a tiny pit in the middle of the macula). It is in this region that vision is most sharp. For this reason, instead of simply staring at one point the eye must constantly â€Å"scan† the area to focus the whole object or image. In order to accommodate the changing distances of the object or image the lens in the eye has to adjust, becoming thinner to focus distant objects and fatter to focus near by objects. This process, of changing the lens thickness is known as accommodation. In order for this to occur the ciliary muscles contract and relax. The contraction fattens the lens and the relaxation stretches the lens. The eye functions on much the same principle as a camera. The iris, or coloured portion of the eye, acts as a shutter to regulate the amount of light admitted to the eye. The cornea (the clear window at the front of the eye) and the lens (located behind the pupil) serve to focus light rays from the object viewed onto the retina at the back of the eye. The retina then transmits the "picture" of the object viewed to the brain where the object is "seen". Clear vision is the result of light rays passing through the cornea,... ...ubstantially reduced. 3) Post-operative visual acuity is restored within a few days rather than weeks. 4) Less corneal scarring in the long term, less change due to healing (regression) and thus greater stability of the correction. When comparing only the benefits of Lasik over PRK the first impression is that Lasik has the potential to be a superior procedure. There is however, a very significant list of potential complications or risks and these include: 1) Failure of automated instrument to leave a hinge on the corneal flap, with the first incision. 2) Loss of the corneal flap during the operation. 3) Loss of the corneal flap after the operation. 4) Slipping of the flap and healing off center. 5) First incision too deep (perforation of the eye) or too shallow, causing a hole in the flap. 6) Invasion of the surface tissue into the central tissue of the cornea. 7) Infection of the cornea. 8) Loss of visual acuity - from scarring or from decentration of the PRK. 9) Technical problems with complex and finicky automated diamond-cutting devices. 10) The procedure is much more dependent upon surgeon's operating skills, than the computerized precision of the PRK procedure.

Pcr And Its Use :: essays research papers

PCR And Its Use Often times, scientists only have a small amount of DNA to deal with when doing genetic research or studies. In these situations, scientists can do one of several things. One is to just try to work with it anyway, but this is nearly impossible (depending on how much there is). Ther are a couple other processes they can use, or they can use PCR. PCR is one of the more complicated, but reliable ways to do tests on DNA when they only have a small amount to begin with. PCR, or Polymearse Chain Reaction, is the scientific process used by genetic scientists to clone DNA. "A 'rapid diagnostic' technique used in the clinical microbiology lab to detect pathogens. It relies upon amplification technology utilizingthe heat stable DNA polymerase from a thermophilic organism." (from http://www.genes.com/pcr/pcrinfo.html) Dr. K.Mullis recently received the Nobel prize for inventing the technique. This is how they go about doing this: They first get their small DNA sample. Then they mix all the chemicals (this includes the primer, etc). Then they have to run it through the PCR machine. Here is a (rather detailed) description of the process: "The cycling protocol consisted of 25-30 cycles of three- temperatures: strand denaturation at 95degC, primer annealing at 55degC, and primer extension at 72deg C, typically 30 seconds, 30 seconds, and 60 seconds for the DNA Thermal Cycler and 4 seconds, 10 seconds, and 60 seconds for the Thermal Cycler 9600, respectively." Basically, that means that they set it to certain temperatures, then put it in different cyles for different amounts of time. PCR machines can be compared with washing machines. There are the different temperatures (here for example, there is 72degC, where in the washing machine you would set it to cold/cold respectively. For it to properly replicate, we must know how to match each of the following: A T G A T A T G G C A G C A A C G A C C A T A the match would be T A C T A T A C C G T C C T T G C T G T A T The whole process is pretty much summed up like this: They heat up the DNA to let the enzymes break it down (or 'unzip' its bonds). Then add specific amounts of the primer (relative to the amount of DNA you have. Then you add the enzyme to sets of 4 nuclotides that will go through the genetic sequence of nucleotides and hook up the matching nucleotide (A goes to T and G to C etc).

Jose Aquino

Sure we have gone a very long way to back in the days Of Martin Luther King J. R. , Blacks/Minorities are not so bluntly discriminated but now in days its as if this new form of subliminally resentful actions are being brought to this day and age. Examples like the recent tragedies regarding Mike Brown and Erick Gardner make my argument even more clear to understand and to prove. Of course there are a few people who believe that the actions the police officers took were necessary. Perhaps they might say, ‘ ‘They asked for it,† â€Å"They Resisted arrest,† they had it coming. Y to them that events such as the police killings are a nexus where white racial resentment and white supremacy are made to confront black/ minority pain, reasonable hurt, and the righteous anger. Why is it that the media has always showed the â€Å"gang member† as a Black or Hispanic male? These are subjects we should be asking ourselves and realize how that can be crucial to some ones perception about a group of people and think about the repercussions all this can have to future generations. Just recently released to the public was data that disappointingly proves the Boston Police department has used racially biased policing.Researchers concluded that police targeted Blacks in 63. 3% of encounters, while Blacks make up less than a quarter of Boson's population. This racial disparity cannot be explained. They also found that Blacks were more likely than whites to be subjected to repeat police/civilian encounters and to be frisked or searched. The bottom line is that race was a significant factor driving the BED'S stop and frisk practices. Those on the opposing side would become speechless to this information. These people who were randomly targeted ere minding there business and going about there day.But because of this current view that society has emplace they were boxed in to this stereotypical box, leading to them being victimized. How do we put an end to all of this? First we need to know our own conscious and unconscious feelings. Perhaps think about what stereotypes we may have and ways we might eliminate these believes or figure out why these ideas have been introduced and of course find the ROOT of this. But perhaps the most important but most difficult is to educate ourselves well enough to hanged the way people think and work within the system so that new ideas and change can be accomplished.The simple fact is that racism both personal, institutional, and structural remains a force in American life. It impacts the lives of everyone, whites included because the result of tension , and shapes the broad material circumstances of minorities in countless negative ways. Yes, there are many ways in which we've made progress, and we should celebrate them. But just because we don't face the racism of the past doesn't mean we've solved the problem.

Bob Dylans Social Commentary Essay

During an interview with the Los Angeles Free Press in 1965, Bob Dylan said, â€Å"All I can do is be me, whoever that is,† (Dylan) which perfectly describes the sentiment you get from his works. During his music career, he has changed many aspects of his image, music style and religion, going so far as to legally change his name from Robert Zimmerman to Bob Dylan. Living during a very fast changing society, his works reflect on the Civil Rights movement and other historically significant events. He is seen as a spokesperson for his generation through his deep and meaningful songs. Bob Dylan uses his pieces to comment on life and humanity, sparking social reforms. Bob Dylan was born named Robert Zimmerman in Duluth, Minnesota on May 24, 1941. He grew up in a supportive, Jewish household, and began writing poems at the age of 10. When he was 14, he taught himself to play guitar, and played in a couple different bands in high school. In college, he read an autobiography of Woody Guthrie which had a tremendous impact on his music career. Bob Dylan performed his versions of the Woody Guthrie’s songs at local coffee houses. Soon, he left college and hitchhiked to New York to visit his sick idol. After his death, Bob Dylan told Rock 100, â€Å"Guthrie was my last idol. My future idols will be myself.† This confidence contributed to his success as a musician. Bob Dylan got his break with a talent scout John Hammond. He released his self-titled first album in March 1962, which was filled with interpretations of old folk songs two original songs. A second LP came out soon after that was only original compositions. Bob Dylan released two more folk LP’s before his big transition into a more electric rock type of music. In 1965 he released a half acoustic half electric album that received a lot of criticism from fans of his folk music. One of his most popular albums, Blond on Blonde, released in 1966 featured many famous rock songs, and received much praise from critics. This album contains many protest songs including â€Å"A Hard Rains a Gonna Fall,† and â€Å"Masters of War.† These songs are thought to have been protesting the arms race during the Cold War, and exemplify how Bob Dylan used songs to comment on humanity and life. After this album, Bob Dylan broke his neck in a motorcycle accident and spent the next couple of years in recovery. After releasing many more successful albums, he went through a major transition from Judaism to Christianity. His next three albums reflected that transition, which confused much of his fan base. Bob Dylan continued to record and toured with a couple different  bands during the 80’s. In 2001, he received a Golden Globe for the best original song in a movie for â€Å"Things Have Changed†. Bob Dylan is still alive and continues to make public appe arances and occasionally perform. Bob Dylan’s songs use symbolism and imagery to reflect his views on life in a different way. The song Blowin’ in the Wind is one of his most famous works. This song uses the phrase â€Å"blowin’ in the wind† to answer multiple questions about humanity that it puts forth. The song also has war themes, shown when it asks the question, â€Å"How many times must the cannonballs fly before they’re forever banned?†(5). The lyrics exemplify his distaste for violence. The whole poem reflects his view that humanity will never learn from their mistakes. Bob Dylan also has some less political and more love themed pieces. In the song Watered down Love, he talks about how pure love will only hurt you so you need to look for a â€Å"watered down love†. The repetitious phrase, â€Å"You don’t want a love that’s pure, you want a drown love, you want a watered down love† (12). The song â€Å"Love is just a Four Letter Word† further continues the theme of true love being impossible. The song begins with him hearing others saying that love doesn’t mean anything, but in the end of the song he believes that himself. This is shown when it says â€Å"Though I never knew just what you meant when you were speaking to your man, I could only think in terms of me and now I understand,† (28). The songs are examples of how Bob Dylan uses his writing to comment on parts of life such as love and war. Bob Dylan’s writing does not go without criticism. His frequent changes in music style and image cause distaste from many critics. Jann Wenner in Rolling Stone Magazine said, â€Å"Dylan created so many images and expectations that he narrowed his room for maneuverability and finally became unsure of his own instincts,†(Wenner,†The Rolling Interview: Bob Dylan.†) There are also arguments of Bob Dylan’s role as an artist. Some believe that his songs do not qualify him as an artist and should not be read and studied as poetry. Others, such as Christopher Rooks, believe that his songs, even if they are not written in a traditional poetic way, are still art because of the â€Å"what they mean and what they can tell us about the human condition, about the nature of reality as it concerns man, which is the  very definition of art,† (Karwowski, â€Å"Is Bob Dylan an Artist?†). In another critical essay, Ellen Willis points out in Cheetah Magazine that although he may be seen as a poet, his poetry ha s â€Å"horrendous grammar, tangled phrases,  silly metaphors, embarrassing clichà ©s, muddled thought; at times he seems to believe one good image deserves five others, and he relies too much on rhyme.†(Willis, â€Å"Dylan†). Although his songs receive a lot of criticism for his changing images and whether he should be seen as an artist, no one can deny the unique way Bob Dylan portrays humanity and his role as a spokesperson for his generation. Bob Dylan is considered to be the greatest influence on popular culture of all time. His surroundings inspired him to write about important historical moments such as the Cuban Missile Crisis, President Kennedy’s assassination, the Civil Rights movement. Many of his songs are directly written about these events, most notably, â€Å"The Death of Emmett Till.†, which was written about the murder of 15 year old Emmett Till, a black boy who was accused of flirting with a white girl. Other songs such as â€Å"Blowin in the Wind,† â€Å"The Times they are A Changing,† and â€Å"A Hard Rains a Gonna Fall† all have political and social meaning behind them. He said that â€Å"the folk songs showed me†¦that songs can say something human.† (Dylan, 86) about his social commentary pieces. Bob Dylan was also a major player in the anti-war protests, sparked by the Vietnam War. His anti-war songs influenced activists, mostly college students who listened to his music. No other artist has had such a profound effect on the cultural evolution in America. He had an incredible influence on social reforms in this generation, as well as inspiring many other famous bands such as the Beatles, the Rolling Stones, Jimi Hendrix, and Eric Clapton. No one can deny that he was a factor in the revolution of hundreds of thousands of people. Bob Dylan uses his songs as a way to comment on life, humanity, sparking social reforms. His childhood during the time period he lived in influenced his writing greatly through watching major historical event occur such as the Civil Rights Movement, World War Two, the Vietnam War and the assassination of President Kennedy. A famous song, Blowin in the Wind talks about society’s inability to change their views, and can be translated to be an antiwar anthem or a Civil Rights commentary. Bob Dylan is criticized mainly on whether his songs can be called poetry and if he can be considered an artist. Also, the politics brought into his writing are very controversial. All in all, Bob Dylan’s songs had a considerable impact on society because of his commentary on humanity. Works Cited â€Å"Bob Dylan.† Encyclopedia of World Biography. Detroit: Gale, 1998. Student Resources in Context. Web. 10 Apr. 2013. Karwowski, Michael. â€Å"Is Bob Dylan an Artist?† Contemporary Review 1 June 2004: n. pag. Print. Wenner, Jann S. â€Å"The Rolling Stone Interview: Bob Dylan.† Rolling Stone 29 Nov. 1969: 32-35. Rolling Stone. Web. 15 Apr. 2013. Wenke, Joseph. â€Å"Bob Dylan.† The Beats: Literary Bohemians in Postwar America. Ed. Ann Charters. Detroit. Gale Research, 1983. Dictionary of Litereary Biograhy Vol 16. Literature Resource Center. Web. 9 Apr. 2013. Yaffe, David. Bob Dylan: Like a Complete Unknown. New Haven [Conn.: Yale UP, 2011. Print.

Twelfth Night, 3.1.1-26

Michael Nodurft English 208 Mrs. Walter Twelfth Night, 3. 1. 1-26 Jan. 30 2007 True Lies Reading this conversation between Viola and Feste the clown there is definite multiple meanings to each of the words that they both say. You can tell that Viola’s wit is matched to Feste’s which makes this conversation so cleverly written. This passage offers pun’s to the audience who understand that Cesario is truly Viola. And have Feste hinting that he knows Viola’s hidden identity. This passage offers hints to the truth of the Viola and the fact that Feste is truly not the fool that everyone believes he is. In this passage I will prove that this conversation is crucial to the plot, and defines beoth of these characters roles. When Feste enters the room he is playing his pipe and tabor, and is being his normal fool self. The first couple lines are normal speech when Viola asks, â€Å"Dost thou live by thy tabor? †3. 1. 1-2 I like how Viola used the word tabor because it is the perfect description of Feste personality, the way he is always playing games with people for money. When Feste’s witty remarks are matched by Viola, Feste begins his more intellectual wittiness. â€Å"A sentence is but a cheverel glove to a good wit,†3. . 10-11 In this sentence you tell that there is a deeper meaning when Feste is talking about a glove. The way that Feste describes the glove to Viola is interesting because when a person uses a glove it is normally hiding the hand. Feste has stumble onto a crucial part of the play making the plot much sweeter for the audience because they know t he truth about Viola and he doesn’t; Cesario is the glove to Viola. This is perfect not only is the fool being a mocked in the play; his fooling is now involving the audience making subtle hints of something he does not know. The next line Feste says is â€Å"How quickly the wrong side may be turned outward. †3. 1. 11-12 I like this comparison between the glove turning outward and Viola trying to keep her cover, because Viola doesn’t know what Feste knows. Another note that I stumbled on when reading this scene was the fact that Feste repeated the word â€Å",Sir,† when he was addressing Viola. When you look into Feste’s lines it is almost like he is mocking the word sir by putting a coma before and after. I can see the imagery of Feste’s face when he pauses and announces â€Å",sir,† I can see his eyes looking into Viola’s almost jesting that he knows that she is not truly a sir but a woman. It seems like Feste knows a lot but I don’t really think he entire understand it yet. So for the audience who knows Cesario is a woman, it is quite enjoyable seeing Feste sort of stuck in the dark and not truly understanding everything. This is how Feste obtains both the fool in the play and to the audience. Another idea that I have thought about was what is Feste hiding? Feste is the loveable fool that plays tricks for money, but is that his true nature? I believe that the â€Å"glove† sentence applies to both characters Viola and Feste. Viola is trying to keep her cover, but one slip up and she could be uncovered causing terrible trouble. On the other hand Feste, if his cover of being a fool is blown then he has no way of living. If one was thinking hard about this speech Feste is talking about himself. Being witty and fun, but at the same time scared to let his more intelligent side out. He has to purposely put himself outside of the box so that no one can understand his true meaning of life. The way that this passage is put together it is not rhythmic at all. The lines don’t flow together like other parts of the play. There is no iambic pentameter is these sentences they are either too long, or too short. I think that Shakespeare purposely made these lines uncut and off rhythm for a reason. This reason is that Feste is a fool and is always being witty never making a direct point. Viola is fooling right back and not being entirely serious as well. From a literary stand point having the fool talk in such a manner makes them both out of the box or â€Å"party†. It makes sense that Feste talks in such a manner in the play, but I like how Viola’s lines are almost the reiterating the argument that Feste and Viola are very similar characters with their wit. I have showed the evidence threw out my paper proving the idea that Feste and Viola are very much alike. I have shown you the style on how they talk to each other using the wit to the best of their abilities. I have proved the non rhythmic lines that complement the fact that both characters are intelligent fools that think they know what they are talking about but are still in the dark. The fact that Feste is messing with Viola the way he does, shows that he has some knowledge on her true identity. The way that Feste mocks Viola makes this passage so important to the plot of the play because of the funny pun’s it gives the audience; hinting at the fact that Cesario is the glove to Viola. All of this evidence digs deeper into this passage and pulls out the hidden pun’s and messages that you couldn’t see with one glance, and enriches the story with hidden thoughts. Shakespeare, William. â€Å"Twelfth Night. â€Å"The Norton Shakespeare based on the oxford edition. 1997.

A Comparative Analysis of Lacatan Banana

Background of the Study We chose this study because we realized how much trees are chopped down to make paper and we realized that we should save more trees.To save more trees, we can use fruit peelings Like the peelings of Lactate and Saba to make handmade paper and If we use fruit peelings we do not Just save trees but we also help reduce wastes. Statement of the Problem This study will compare Lactate Banana (MUSM communicate) and Saba (MUSM geminate x MUSM balancing) as a Component of Handmade Paper. 1. Which is much banana is much better to use as a component of handmade paper? 2.Will this study help and benefit the community? Objectives This study mainly aims to use food wastes, specifically kinds of banana peelings as a component of handmade paper and to save more trees and to help reduce Hypothesis If this study proves that Lactate or Saba banana peelings can be components of handmade paper then they can be alternative for paper. Significance of the Study To make paper, we ch op down trees and we use harmful chemicals.Now this study can produce paper without using harmful chemicals which will be a big help to Mother Nature because we reduce wastes and lessen the trees being chopped down. Definition of Terms Lactate banana (MUSM communicate) : most popular dessert banana In the Philippines; has a higher vitamin content, compared to the Aleutian (white with thinner skin) and Saba varieties (used for abundance).

Analyzing The Micro Business Environment For Tesco Marketing Essay

Analyzing The Micro Business Environment For Tesco Marketing Essay My organisation for this assignment is â€Å"Tesco†. It is leading food and grocery retailers on the planet. The aim of this essay is to analysing the micro business environment, Identify the core resources and competences of the organisation, Evaluate the organisation’s strategic choices and justification of the strategy of the company. I have used Strategic evaluation tools such as PESTEL, SWOT and others. Tesco is among the biggest food retailers in the world with returns in surplus of  £54 billion in 2009 and over 470,000 workers. It has 4,331 stores in 14 countries.   The company’s Head Office is based in Hertfordshire, UK and operates mainly in the USA, Europe and Asia(www.tescoplc.com ). PESTEL Analysis (J. L. Fowle, September ,1993), analyses the vibrant and erratic environment in which company operates by classifying the forces that have the most influence on its performance, Influences Company has, to achieve strategically success. Porter’s Five forces can also be used to analysis competitive environment. However these forces becomes interrelated at some times. And its Tesco’s vision to expand globally, encouraged me to use PESTEL forces analysis rather than any other model. Political decision has always been at watch by companies like Tesco. China is one of the world most profitable market, worth over 1.3 billon, Now it has open it door for world and encouraging Western companies. Tesco has managed to signed agreement in 2009 to set up thought-out series of joint ventures for development of shopping malls in i.e. Anshan, Fushun and Qinhuangdao(http://www.fas.nus.edu.sg/ ).By end of 2010 18 more hypermarkets are expected to open in China(http://www.investis.com/ ).   Such rises of Tesco’s international business segment are predicted to account the company’s profit for one quarter. In 2004 immersion of 10 further countries into the EU took place, encouraging trade between Western and Eastern Europ ean countries(http://www.eu-27watch.org/ ).Helped Company to enter into new market, and increase its market share across Europe. Economic forces are of great concern to any company as they impact directly on the buying behaviour of its customers. The UK economy was officially declared under recession in 2008, the government’s was successful in minimising the rises in unemployment by considerable reduction in interest rates during 2009 (www.euromonitor.com ). This has given rise in spending power of English people,but both sales value and margins are effected as consumers are not or less likely to divert their spending on more of premium or high value goods. According Maslow hierarchy of need consumers would be at top of Basic need. (http://www.ict-learningnow.com). But retailers like Tesco would still be benefited, as their low price strategy would encourage its customers to shop from Stores and cook and dine home rather than spending more on restaurants(www.guardian.co.uk ).   As we all know that food is the last thing that customers will sacrifices .   The percentage of overall consumer spending on food has risen over the years. Social forces are quite obvious as Man is Social Animal. An analysis has proven that the UK has the Baby Boom generation and latest medical facility by NHS Trust has reduced the death rate too(www.statistics.gov.uk ).This means that more retired people eats less and less spending power. It’s not expected of them to travel to supermarket for shopping and at the age of 65 internet literacy level go down, But it is still assumed that online shopping is and would be the only convenient way of shopping for older age people.   The ageing population is discouraging for the food retailers older people tend to eat less. Company still have to bear in mind the ineffective and expensive small deliveries. However taste and preferences of consumers should always bear in mind when strategies are framed. As mentioned on Economica l forces, high value goods would be avoided but the standard of leaving would have great influence.