Looking back over this quarter, what have you learned about one Essay

Looking back over this quarter, what have you learned about one particular adventist belief that is new to you, or is a significant addition to what you have thought previously - Essay Example Because of that, this class has certainly made me think about things in different ways, even if it did not really make me believe the same things that the Seventh Day Adventists do. One of the biggest and most obvious differences is the fact that those in the Adventist religion believe in the idea that Jesus Christ is the savior of humanity. Obviously, this is not a belief in Islam. Much like other Christian denominations, the Seventh Day Adventists believe that if you accept Christ as your savior, then you will be free from sin and able to go into heaven. By contrast, Islamic people believe that only Allah can free you from sin, and that you must genuinely repent and atone for your sins first. That means that in Islam each person is in charge of clearing himself from sin, and that it cannot be done by simply accepting a particular prophet as your I think there are some interesting things to say about both the Islamic and the Seventh Day Adventist beliefs about sin. For one thing, as a Muslim I am not sure that it is a very good idea to tell every single human being that they can be cleaned of sin simply by believing that the son of God has been punished for the sins that you commit. I think that it is much more helpful to society and to the world if, instead, every individual person has to properly and fully repent for the sins that they have committed before Allah (or God). That way, each person really thinks about what they have done thats wrong, and will truly feel sorry about it, so they are less likely to sin again. In Seventh Day Adventism, I would worry that people might not really repent from the sins they have committed, and this might mean that they would do the same thing again. On the other hand, the Seventh Day Adventist belief in Christ is like that of other Christian churches. They believe that while he is the son of God, he is also God himself. In this case, then, there is not much difference in having Christ

Box 13.2 Crisis Preparedness Scale Essay Example | Topics and Well Written Essays - 750 words

Box 13.2 Crisis Preparedness Scale - Essay Example X 5 Legal considerations do not override ethical and human concerns. X 6 Our organization has a trained crisis management team (CMT) that can assemble quickly and make effective decisions. X 7 Our organization has the capabilities to investigate and determine a. the precise type or nature of whatever crisis could occur. X b. the early warning signals that precede each type of crisis. X c. whether such signals were blocked or ignored. X d. the exact, human, organizational, and technical causes of a crisis. X 8 Our organization has properly designed, constantly maintained, and regularly tested damage containment systems in place. X 9 Our organization has backup manufacturing equipment and computers so that it can resume operations as quickly as possible. X 10 Our organization has recovery mechanisms to restore full site and organizational operations. X 11 Our organization has recovery mechanisms to restore the surrounding community and environment. X 12 Our organization has the capabil ities to communicate effectively, notify the proper authorities, respond to the media, and reassure a wide array of stakeholders. X If you answer no to two or more of these statements it is likely that your organization will have a crisis and that it will have difficulty handling it properly. 1. Short summary of results The preceding assessment indicates that the organization I am assessing has general provisions for addressing crises of a general sort, and provides for the manpower, equipment, and resources for most crises as they occur within the organization. It does not, however, have sufficient capability to quickly and accurately assess all types of injuries that may result in a crisis, nor does it have sufficient resources or provisions to restore the community or surrounding environment outside of the organization. It is doubtful that a quick and accurate assessment of the exact cause of the crisis could immediately be determined on its own without expert help. 2. What the r esults reveal about leadership communication behaviours The results reveal that leadership communication behaviours in this company fail to give due attention to important details about the causes and repercussions of the crisis, and likewise fail to go beyond the immediate confines of the organization. There is also a lack of importance given to people, both within and outside the organization. Because of this, my self-understanding has increased about the necessity of ascertaining details, especially in the human aspect, when assessing the effects of a crisis, because lack of detail compromises the effectiveness of any general crisis response plan that the management may have drawn. The assessment also reveals that in my role as leader or follower, my potential strength lies in my empathy with the human aspect, whether they involve the employees of the organization or the community, because I am able to appreciate the need for the human focus, and possess an insight about how it c ould be enhanced. On the other hand, I believe my weakness is in the establishment and operation of a mechanism to determine details such as the exact causes of a crisis. As far as I can perceive, a developing crisis is manifested by certain situations, but it will take a post-crisis assessment to determine the exact causes. While the crisis is unfolding, it appears highly unlikely that the exact cause of it may be immediately determined. In this weakness, I believe that the

In the play Hamlet by William Shakespeare Essay Example for Free

In the play Hamlet by William Shakespeare Essay In the play Hamlet by William Shakespeare, one of the main themes is the discrepancy between appearance and reality. The development of this theme through the plot, soliloquy and imagery help to reinforce the players role in the play and directs the audience to where their allegiances should lie for the climax of the play. The theme appearance versus reality is clearly evident throughout this Shakespearean play; it is introduced at the very beginning through Claudius speech to the court. The structure and rhythm of this blank verse carries him through but the imagery that Shakespeare uses signals to the audience the corruption in Denmark he uses phrases such as defeated joy, one auspicious and one drooping eye and wisest sorrow. These opposing images and hollow phrases reveal the hypocrisy of the diplomats words; how can a person have one auspicious and one drooping eye unless they are duplicitous? Claudius opening speech is also eloquent, relaxed and so carefully structured that it appears rehearsed he deals with three items of business before confronting his black-suited nephew: Old King Hamlets death; the threat from Fortinbras army; Laertes impending departure to France. Shakespeare here signals to the audience that Claudius is uneasier than he appears by leaving his nephew and son-in-law to deal with last. In my opinion, the exposition of Claudius Machiavellian mature at the beginning through the theme appearance versus reality is very effective as it reveals to the audience the corruption in Elsinore which essentially instigates Hamlets revenge and also exposes Claudius at the beginning of the play as the antagonist, aligning the audiences sympathies. Furthermore, this main theme is developed through the soliloquies in particular Claudius. During his agonised soliloquy, Claudius puts on the appearance of praying but he is pseudo-sincere in this: Pray can I not, though inclination be as sharp as will. This reveals Claudius confessing to the murder of his brother but not repenting for his sins. As he is not sincere in this, he believes that he will not go to heaven: My words fly up, my thoughts remain below, words without thoughts never to heaven go. This rhyming couplet not only reveals the theme appearance versus reality, but is also richly ironic as this prayer actually saves his life. Shakespeare also employs the transferred epithet stubborn knees to further emphasise Claudius reluctance to repent for his sins and how he is putting on the appearance of praying, albeit mendaciously. In my opinion, the development of the main theme through Claudius soliloquy successfully polarises Claudius from the protagonists and reinforces him as the villain in the play, directing the audience to where their allegiances should lie for the climax of the play. In addition, Shakespeare conveys the theme appearance versus reality through Hamlets antic disposition. This is illustrated particularly well through Hamlets exchanges with Polonius: Let her not walk ithsun. Conception is a blessing. But as your daughter may conceive friend, look tot. Although these words sound like nonsense to Polonius and the audience, there is a thread of bitter satire running through them. Hamlet reveals his witty sarcasm here as he is aware that Ophelia has been prevented from seeing him and tells Polonius that he should not let her walk in the sun if he wishes to prevent her becoming pregnant. Hamlets antic disposition is reinforced throughout the play but particularly through his exchanges with Claudius: Excellent ifaith of the chameleons dish. I eat the air, promised crammed. You cannot feed capons so. Hamlet here is trying to make Claudius think that he is frustrated at not being the King; Claudius pretends not to understand him. In my opinion, Shakespeare effectively polarises Hamlet from Claudius through his antic disposition and wit which in turn successfully aligns the audience with the protagonist for the denouement. Furthermore, it could be argued that the theme of surveillance intertwines with the main theme appearance versus reality which helps to further develop the audiences awareness of the conflict between reality and appearance. For example, Hamlets conversations with the two people he loved, Gertrude and Ophelia, were eaves-dropped by Polonius. As a result of the spying, Ophelia and Gertrude spoke to Hamlet with constrained formality: How does your honour for this many a day? . This heated exchange between the eponymous prince and Ophelia during the nunnery scene recapitulates arguably the main theme of the play; appearance versus reality which is exposed at the very beginning and is reiterated through Hamlets exchanges with Rosencrantz and Guildenstern they also spy on Hamlet for Claudius: they did make love to this employment! . In my opinion, Shakespeare effectively evokes sympathy for Hamlet and his little allies through dramatic irony and further polarises Hamlet and Claudius through the development of this main theme hence reinforcing Hamlet as the tragic hero of the play. In conclusion, the development of the theme appearance versus reality is essential in augmenting the audiences understanding and appreciation of the play as a whole. In my opinion, Shakespeare effectively develops this main theme through the plot, soliloquy, imagery and dramatic irony which successfully reinforces the players role in the play and also directs the audience to where their sympathies should lie for the denouement.

Erosive Potential of Fruit Juices on Primary Teeth

Erosive Potential of Fruit Juices on Primary Teeth In Vitro evaluation of erosive potential of frozen and unfrozen fruit juices on primary teeth ABSTRACT: Dental erosion has gained importance now as a steadily growing public health problem world wide. Fruit juices are an important etiological factor, especially consumption in frozen forms, like fruit lollies and stick. Since this dietary habit is more prevalent among children, primary teeth were selected for this study. AIMS: To evaluate pH and titratable acidity of four fruit juices in frozen and unfrozen forms. Calcium dissolution and pattern of etching of enamel by these juices in frozen and unfrozen forms were also determined. DESIGN: pH of four different juices apple, orange, musumbi and grapes were determined using a digital pH meter. The titratable acidity of these in frozen and unfrozen forms were determined by adding 0.5 ml of 1N NaOH to these, till a pH=five and pH = seven were reached. Forty eight caries free deciduous anterior teeth specimens were prepared to study the etching pattern by scanning electron microscope [SEM] and calcium dissolution by atomic absorption spectrophotometer.STATISTICAL ANALYSIS: One-Way Repeated Measures ANOVA and pair wise multiple comparison with Bonferroni correction. RESULTS: Increase in titratable acidity, irregular pattern of etching and calcium dissolution were found to be significantly more in the initial thawed frozen fruit juices. Grape juice recorded the lowest pH and more titratable acidity when compared to other juices. CONCLUSION: This study highlights the detrimental effect on teeth by the frequent consumption of fruit juices and their frozen products. Th e study concluded that sucking on the frozen fruit juice products were more harmful than consuming in unfrozen state because more of erosion occurs in frozen state. Key words: Frozen fruit juices, pH, titratable acidity, erosion, etching, SEM. Introduction: â€Å"HEALTHY LIVING â€Å"the key to survival has been emphasized by health professionals upon the old and young alike. The â€Å"DIETARY FACTOR† is gaining much accolade and health drinks in the form of fruit juices have gained tremendous popularity in this category. Parents regard these as being healthy and nutritious and a good source of Vitamin C.[1]. Experiments conducted on the animals to evaluate the erosive potential of fruit juices showed that these juices were ten times more destructive to the teeth than the whole fruit.[2] Most fruit juices have a low pH and acids which can decalcify the teeth.[3] Hence, the frequent consumption of these fruit drinks is directly related to dental morbidity, especially erosio n.[4]Dental erosion has been defined as superficial loss of dental hard tissue by a chemical process not involving bacteria.[5] The aetiopathogenesis can be varied (intrinsic and extrinsic factors),most important are dietary acids.[6] A modern habit among consumers is to freeze and suck out fruit lolly and candies.Sucking on frozen fruit juices has a greater risk for erosion due to slow consumption and longer time required to neutralize it[7].Sucking of the melting juices from the frozen product is a pleasurable experience along with increase in the initial acidity and buffering capacity.[8]Hence the frequent use of these could produce damaging effects on the teeth. Primary teeth were included in this study,because children are frequently involved in the consumption of frozen fruit juices and deciduous teeth are more susceptible to erosion than permanent teeth due to less mineralisation and immature enamel surface[9] The study was performed to evaluate the pH of four fruit juices in a frozen and unfrozen form. The titratable acidity of these fruit juices to be checked. The total amount of calcium dissolved in fruit juices from the teeth and to study the pattern of etched enamel on teeth. MATERIALS AND METHODS: Preparation of juices: Two and half litres of four different fresh fruit juices namely apple, orange, grape and musumbi each were prepared with no added sugars or preservatives. These were allowed to equilibrate to room temperature. Specimen preparation: Fourty eight freshly extracted caries free deciduous anterior teeth were collected and were used in the study. Extracted teeth were completely coated with nail polish with the exception of a window on the enamel of the labial surface of approximately 2mm X 2mm in diameter. Method: Two and half litres of apple juice were shaken for 15sec and this was divided into four samples of 600ml each. First sample (600ml) of this was taken and calcium concentration was assessed. From this, 100 ml was separated, pH and titratable acidity were determined.Then another 100 ml was taken and a prepared tooth specimen was dipped in it for two hrs.(For assessment of calcium etching pattern at room temp). Remaining 400ml was taken in a bottle, sealed and placed in a recorded (-200c) deep freezer for 24 hrs. The bottle was taken and allowed to defrost. From this, initial 100ml was taken, pH and titratable acidity were determined. Then another 100 ml was taken and a prepared tooth was dipped in it for two hrs( For assessment of calcium etching pattern immediately after defrosting). Remaining 200 ml was defrosted for two hours. Then 100 ml of this was taken and pH and titratable acidity were determined. Another 100 ml was taken and a prepared tooth was dipped in it for two hrs (For assessment of calcium etching pattern two hrs after defrosting). This was repeated for remaining three samples (600ml each) of apple juice. The same procedure was done for the other three juices musumbi, orange and grape juice and the values recorded [Table1,2,3] Determination of pH and titratable acidity: pH was determined by using a pH meter (digital pH meter model –EQ-612). After determining the pH, the juice was titrated against 1N( Na OH )Sodium hydroxide by adding 0.5ml of the same to the juice, mixed well and this were repeated until pH=five and pH=seven were reached to determine their titratable acidity. Assessment of calcium content: The teeth were carefully lifted out of the juices and the juices were centrifuged at 3500 rpm for five min. With the help of micropipette [superfit] 200ÃŽ ¼l of each of these samples of fruit juices were pipetted into the polypropylene tubes. Then 40ÃŽ ¼l distilled water were rinsed into the polypropylene tubes with the fruit juices. Then concentrated nitric acid (120ÃŽ ¼l) were added, the lid of the polypropylene tube sealed and the contents of the tube were wet washed, by leaving it at 600c for 12hrs. After cooling, 50ÃŽ ¼l of one mol/L KCl solution (an ionization suppressant) and 680ÃŽ ¼l of distilled water were added. Then samples were shaken and the calcium concentrations were determined by the use of a flame (nitrous oxide/acetylene) atomic absorption spectrophotometer. To obtain calcium content of the fruit juices (without teeth), 200 ÃŽ ¼l of the fruit juices were wet ashed and atomized exactly as mentioned above. Determination of etching pattern: The teeth specimens were prepared for SEM observation by dehydration followed by sputter coating of 20 nm of gold (JEOL,JFC 1100 E-JAPAN) and examined under a scanning electron microscope (JEOL,JSM-840A-JAPAN).Instant photomicrographs were made at X850,X1000 magnifications. Subsequently the X1000 magnification pictures were selected to compare the pattern of etched enamel surfaces. Statistical analysis: The data obtained were subjected to statistical analysis by using One-Way Repeated Measures ANOVA and Pair wise multiple comparison with Bonferroni correction RESULTS: RECORDED pH VALUES OF FOUR FRUIT JUICES (Table 1) Based on the results obtained in Table 1, the pH values of all the juices were less than 5.5, which is the critical pH, below which enamel dissolves. Grape juice recorded the lowest pH of 2.2 among the juices. TITRATABLE ACIDITY VALUES OF FOUR FRUIT JUICES (Table 2) For all the four fruit juices tested, the volume of 0.5 ml 1N NaOH needed to reach pH=five and pH= seven were more for immediate defrosted( initial thawed )juices than the juices at room temperature and that defrosted for two hrs. Hence, the immediate defrosted juices had more titratable acidity compared to the juices tested at other temperatures. Among the juices, grape juice had more titratable acidity. CALCIUM CONCENTRATION IN FOUR SAMPLES OF FRUIT JUICES MEASURED BY ATOMIC ABSORPTION SPECTROPHOTOMETER ( Table 3) The amount of calcium dissolution in the juices from the teeth were found to be significantly more in the immediate defrosted juices than the room temperature juices and that defrosted for two hours. Evaluation of SEM Images : Representative SEM photomicrographs at magnification X1000. For teeth immersed in juices at room temperature, relatively smooth and slightly etched enamel surfaces were seen.[Figures 1- 4] Teeth dipped in juices immediately after defrosting, showed maximal erosion. Among these, apple showed eroded surface with enhanced porosity[figure5],a honeycomb enamel prism pattern noted in musumbi similar to that seen in acid etched enamel[figure 6].Teeth in orange and grapes showed more erosion resembling type II acid etching pattern [figures 7,8]. In case of teeth kept in juices two hrs after defrosting, the changes were similar to those seen at room temperature [figures 9-12]. DISCUSSION: The awareness of the population about health has lead to an increased consumption of natural food products, especially fruits and fruit juices. But fruit juices contain substantial acids(eg: citric acid in citrus fruits, malic acid in apples, tartaric acid in grapes)[10]which have the potential to cause loss of tooth tissue.[11][12] Various extrinsic and intrinsic factors contribute to dental erosion like diet, medicaments, occupation, sports, GERD, peptic ulcer, uremia etc.[13][14]But most significant among these are dietary acids .[3][4][15] Dental erosion due to dietary acids are influenced by a variety of factors like pH, titratable acidity, temperature, concentration, frequency, and exposure time[16].Many host factors also modify erosion, most important is saliva[17].Reduced salivary flow rate leads to inadequate oral clearance of dietary acids. Consumption of juices at night increases the erosive potential as salivary flow rate is diminished during this period. [18].Also different studies on salivary flow rate indicated that young children have lower flow rate, resulting in defective oral clearance. [19]. Intake of dietary acids decreases pH of the oral environment. Gregory-Head B et al[20] suggested that the pH of the oral cavity affected the solubility of the dental tissues. The critical pH at which the chemical dissolution of enamel occurs is accepted to be 5.5 ±0.3.[4][21]In this study, all the four fruit juices namely in the order of grape, orange, musumbi and apple showed a pH below five, thus enhancing the enamel dissolution capacity.[22] Titratable acidity which denotes the hydrogen ion availability has been acknowledged as a true indicator of erosive potential rather than pH value alone[23].Studies conducted by Touyz etal[8] have shown that fruit juices have a high intrinsic buffering capacity.Modifying the form in which the fruit drinks are taken (sweets or frozen lollies) is expected to increase erosion[24][25]. Sucking frozen fruit juices could be more erosive than unfrozen fruit juices because of increase in buffering capacity of initial thawed juice[8][26].. The acidity increases on freezing, as the physical state of the residual juice changes. When juice is frozen, water alone is solidified to ice without the solute. The solutes accumulates undiluted (concentrated). When juice is defrosted, the initial(concentrated) melt is more acidic with increased buffering capacity Thus sucking on these could cause a greater fall in oral pH and requires more buffering action to normalize the oral environment pH .As the remaining ice melts and dilutes the solution back to pre-freezed state, the buffering capacity diminishes.[8] The calcium dissolution potential of these fruit juices was analyzed. It was found to be more in the initial thawed fruit juices than juices tested at other temperatures. This is in accordance with the findings of M.Silove [8][26] who suggested that sucking frozen fruit juices can lead to more calcium dissolution than unfrozen juices. Also in our study, lowest calcium concentration was found in grape juice which is in accordance with studies stating that the erosive potential of drinks are associated with low calcium concentration[27] SEM was done to qualitatively estimate enamel surface alterations. Irregular and pitted enamel surface were observed in teeth exposed to frozen juices than at room temperature and after two hours of defrosting. Different etching patterns as described earlier were observed. [28-30] Similar studies were done on commercially available fruit juices and they are found to be 6-8 times more erosive than homemade juices. [31-33]The significance of this study was that, it was done in pure fruit juices, in frozen and unfrozen forms and multiple parameters were analyzed. The results showed that even pure fruit juices had erosive potential, especially in frozen forms. This study was done in vitro conditions, the results cannot be completely extrapolated to in vivo process, as interplay of various oral factors like salivary buffering capacity and flow rate to counteract erosion were not included in the study. [17] Recommendations: Although fruit juices are good for health, the frequency, method of drinking and the form in which they are consumed are important factors in dental erosion. Since children are frequently involved in the sucking of frozen fruit juice products, pediatric dentists should strongly discourage them from practicing this form of habit. Advise them to avoid fruit juices at bedtime and always rinse mouth with water after consumption of juices. Another point to consider is the use of additives which alter the pH and titratable acidity, thereby reducing the erosive potential of fruit juices. This requires further study. References: 1. Touyz L.Z.G . The Vitamin C contents of foods. J DASA 1982;37:444-48 2. Miller C.D.Enamel erosive properties of fruits and fruit juices.J Nutr 1950;41:63-67. 3. Touyz L.Z.G,Glassman R.M. Citrus acids and teeth. J DASA 1981;36:195-201 4. Eccles J.D,Jenkins W.G. Dental erosion and diet. J Dent 1974;2:153-159 5. R.Rajendran, author. Shafer’s textbook of Oral Pathology,5th Edition. Elsevier India 6. Lussi A,Jaeggi T,Zero D.The role of diet in the etiology of dental erosion.Caries Res 2004;38 suppl 1;34-44. 7. Kevin H-K Yip,Roger J Smales,John A Kaidonis.The diagnosis and control of extrinsic acid erosion of tooth substance.General dentistry 2003;350-353. 8. Touyz L.Z, Silove M. Increased acidity in frozen fruit juices and dental implications.ASDC J Dent child 1993;60:223-225. 9. Johansson AK,Sorvari R,Birkhed D,Meurman JH.Dental erosion in deciduous teeth-an in vivo and in vitro study.J Dent 2001;29:333-40. 10. Eccles J.D. Erosion affecting the palatal surfaces of upper anterior teeth in young people.Br Dent J.1982;152:375-378 11. Touyz L.Z.G. Apples, acids and teeth. S.A.J Sci 1980;76:200-201. 12. Grobler S.R,Aalbers J and Vander Horst G. The pH, calcium, potassium and phosphorus content in South African fruit juices. J. Dieteics Home Econ 1983;11:95-98 13.Jarvinen VK,Rytomaa II,Heinonen OP.Risk factors in dental erosion.J Dent Res 1991;70:942-947 14.Zero DT.Etiology of dental erosion-Extrinsic factors.Eur J Oral Sc 1996;104:162-177 15. Asher C,Read MJF. Early enamel erosion in children associated with the excessive consumption of citric acid. Br Dent J 1987;162:384-387 16. WestNX, Hughes JA, Addy M.Erosion of dentine and enamel in vitro by dietary acids:the effect of temperature,acid character,concentration and exposure time.J Oral Rehabil 2000;27:875-880. 17. Piangprach T,Hengtrakool C,Kukiattrakoon B,Kedjarune-Leggat U.The effect of salivary factors on dental erosion in various age groups and tooth surfaces.J Am Dent Assoc 2009 Sept;140(9):1137-43. 18.Millward A,Shaw L,Smith AJ,Rippin JW,Harrington E.The distribution and severity of tooth wear and relationship between erosion and dietary constituents in a group of children.Int J Pediatr Dent 1994;4:152-157 19.Crossner CG.Salivary flow rate in children and adolescents.Swed Dent J 1984;8:271-6 20. Gregory Head B, Curtis D. Erosion caused by gastro esophageal reflux :diagnostic considerations. J Prosthodont 1997;6:278-285 21.Jenkins,G.N.The physiology and biochemistry of the mouth.4th edition.Oxford, Blackwell,1978, pp 360-413. 22. Jenkins G.N. The influence of environmental fluids on enamel solubility.J Dent Res 1966;45:662-669. 23. Owens BM.The potential effects of pH and buffering capacity on dental erosion.Gen Dent 2007 Nov-Dec; 55(6):527-31. 24. M.J Larsen B.Nyvad. Enamel erosion by some soft drinks and orange juices relative to their pH buffering effect and contents of calcium phosphate. Caries Res 1999;33(Supplement 1):81-87 25. Holloway P.J , Mellanby M. and Stewart R.J.Fruit drinks and tooth erosion.Br Dent.J 1958;104:305-9 26. Louis LZ,G Touyz.The acidity and buffering capacity of Canadian fruit juices and dental implications. Scientific Journal 1994;60:454-48 27. West NX,Hughes JA, ParkerDM, Newcombe RG,Addy M.Development and evaluation of a low erosive black currant juice drink.2.Comparison with a conventional black currant juice drink and orange juice.J Dent1999 ;27:341-344 28. Imfeld T:Dental erosion.Definition,Classification and links.Eur J Oral Sci 1996;104: 151-155 29.Mannerberg F.Changes in the enamel surface in case of erosion.A replica study.Arch Oral Biol 1961;4:59-62 30.Silverstone,Saxton,Dogon. Variations in the pattern of acid etching of human enamel examined by SEM. Caries Res 1975;9:373. 31. Albert Schuurs.Pathology of the hard dental tissues.Ist edition.Wiley-Blackwell;2013. pp158-159 32. Shaw L,Smith A.Erosion in children:An increasing clinical problem?Dent Update 1994;21:103-106. 33. Tahmassebi JF, Duggal MS, Malik-Kotru G,Curzon MEJ.Soft drinks and dental health:a review of the current literature.J Dent 2006;34:2-11

Christianity and The Chronicles of Narnia Essay -- Chronicles of Narni

Christianity and The Chronicles of Narnia      Ã‚  Ã‚   C. S. Lewis, a well-known author and apologist, is best known by people of all ages for his seven volume series entitled The Chronicles of Narnia. As Lewis wrote about the land of Narnia, an imaginary world visited by children of this world, he had two obvious purposes: to entertain the readers and to suggest analogies of the Christian faith. Although some feel that his stories are violent, Lewis is successful at using fiction to open peoples' hearts to accepting Christ as their Savior because he first entertains the audience with a wonderful story.    Lewis talked about how he came to write the books of Narnia, saying that they "all began with a picture of a Faun carrying an umbrella and parcels in a snowy wood" (Lewis 79). The Chronicles tell of the different adventures of English children as they visit the kingdom of Narnia and fall in love with the lion Aslan. Aslan, "the son of the Emperor over Sea," can be compared to this world's Jesus Christ (Schakel 133). As a child, Lewis always favored fairy tales and fantasies; as an adult, he decided to write one (Lewis 60). And so began The Chronicles of Narnia. Rather than planning to write a fictional book that succeeded in using apologetics, Lewis admits that the "element" of Christianity, "as with Aslan," entered "of its own accord" (Hooper 31). Walter Hooper, C. S. Lewis' biographer, describes Lewis as being the most religious man he ever met (Schakel 132). For this reason, no matter what Lewis wrote, his religion would greatly impact all of his works.    Although Christian symbolism can be found... ...rtainer.    Works Cited    Dorsett, Lyle W. and Marjorie Lamp Mead, eds. C. S. Lewis Letters to Children. New York: Macmillan Publishing Company, 1985.    Holbrook, David. The Skeleton in the Wardrobe: C. S. Lewis's Fantasies: A Phenomenological Study. Lewisburg: Bucknell University Press, 1991.    Hooper, Walter. Past Watchful Dragons: The Narnian Chronicles of C. S. Lewis. New York: Collier Books, 1979.    Lewis, C. S. Of This and Other Worlds. Ed. Walter Hooper. St. James Place, London: Collins, 1982.    Martin, Holly Bigelow. "C. S. Lewis in the Secular Classroom." The Bulletin of the New York C. S. Lewis Society 22.4 (1991): 1-7.    Schakel, Peter J. Reading with the Heart: The Way Into Narnia. Grand Rapids, Michigan: William B. Eerdmans Publishing Company, 1979.   

Software Piracy :: essays research papers

Software Piracy What is Software Piracy The PC industry is just over 20 years old. In those 20 years, both the quality and quantity of available software programs have increased dramatically. Although approximately 70% of the worldwide market is today supplied by developers in the United States, significant development work is occurring in scores of nations around the world. But in both the United States and abroad, unauthorized copying of personal computer software is a serious problem. On average, for every authorized copy of personal computer software in use, at least one unauthorized copy is made. Unauthorized copying is known as software piracy, and in 1994 it cost the software industry in excess of US$15 billion. Piracy is widely practiced and widely tolerated. In some countries, legal protection for software is nonexistent (i.e., Kuwait); in others, laws are unclear (i.e. Israel), or not enforced with sufficient commitment (i.e., the PRC). Significant piracy losses are suffered in virtually every region of the world. In some areas (i.e., Indonesia), the rate of unauthorized copies is believed to be in excess of 99%. Why do People Use Pirated Software? A major reason for the use of pirated software is the prices of the REAL thing. Just walk into a CompUSA, Electronics Boutique, Computer City, Egghead, etc and you will notice the expensive price tags on copies of the most commonly used programs and the hottest games. Take the recent Midwest Micro holiday catalogue for example and notice the prices. Microsoft Windows 95: $94, Microsoft Office 95: $224, Microsoft Visual C++: $250, Borland C++: $213, Corel Draw 7: $229, Corel Office Professional 7: $190, Lotus Smartsuite 96: $150, Microsoft Flight Simulator95: $50, Warcraft 2: $30. The list goes on and on and the prices for the programs listed above were only upgrade versions. Users of the software listed above include anywhere from large companies like AT&T to yourself, the average user at home. Although a $30 game like Warcraft 2 doesn't seem like much, by the time you finish reading this paper, it will seem like a fortune. Ease of Availability Since the law states clearly that making a copy of what you own and distributing it or installing more than one copy of one piece of software on two separate computers is illegal, then why do the average Joes like you and us still do it? There are many answers to that question and all of them seem legitimate except that no answers can be legally justified. A friend borrowing another friend's Corel draw or Windows 95 to install on their own PC is so common that the issue of piracy probably doesn't even come to mind right away or

Electrical and Electronics

This effect can be used to build an electric power generator, such as the one described in this paper. A coil attached to a shaft spins within the magnetic field ofa â€Å"U† shaped magnet. Three conveniently designed conductive disks allow the electrical load of the generator to be fed either with alternating current or direct current. the loop terminals is sinusoidal with zero mean value (Fig. 2). Its frequency is equal to the number of revolutions per second executed by the loop. Each terminal of the loop is connected to a metallic ring. The contacts with rings are made by means of fixed brushes.If the brushes are onnected to an electrical load, an alternating current will be established in the circuit. Keywords. Alternating Current, Direct Current, Generator, Magnetic Field, Induced Voltage. 1. Introduction Although diverse forms of energy (mechanical, thermal, chemical etc. ) can be converted into electrical energy, the expression electric generator is reserved, in the in dustry, energy into electrical energy. The generators that produce direct current (DC) are called dynamos and the ones that produce alternating current (AC) are called alternators.The device described in this paper is a generator capable of supplying an electrical load ith the desired type of current: alternating current or direct current. s AC output Figure 1. AC generator. 2. AC generator principle of operation. Figure 1 illustrates the principle of operation of an AC generator. A wire loop rotates within the magnetic field generated by a magnet, which induces an AC voltage between the loop terminals. The periodic change of the voltage polarity is due to the change of the position of the coil relatively to the magnetic poles.The amplitude of the voltage depends on the magnetic field strength and is also directly proportional to the rotating speed [1, 2, 3, 4]. If he magnetic field is uniform and the rotation speed is constant, the voltage induced between Figure 2. AC generator out put. 3. DC generator principle of operation. The described AC generator may be transformed into a DC generator, substituting the contact rings by a mechanical switch. As illustrated on Fig. 3, a simple switch may be done with a metal ring divided into two isolated halves (segments), which are mounted in the axis.This type of commutator is denominated collector. segment of the collector. When the loop rotates, an AC voltage is induced in the coil, exactly as in the AC generator. But, before reaching the oad, the induced voltage is transformed into a DC voltage by the collector (Fig. 4), which works as a mechanical rectifier. The contact segments of the collector move to a different brush each half turn of the loop, keeping a unidirectional current flowing through the electrical load of the circuit [1]. The rotation speed has to be well determined so that the final result is the expected one.As stated before, the rotation speed influences the induced voltage amplitude and frequency. à ¢â‚¬Å"U† shaped strong permanent magnet, shown in Fig. 6. The most challenging part to build was a contact rings and collector unit (Fig. 7). It was ade of three printed circuit board disks, coaxially mounted on the rotating axis. The two smaller disks were kept with their entire conductive layer and were intended to supply the generated AC voltage. The conductive layer of the larger disk was cut into two halves, in order to implement the collector, which mechanically rectifies the generated AC voltage.Figure 5. Coil with iron core. DC output Figure 3. DC generator. Figure 6. Permanent magnet used to induce a voltage in the coil. Figure 4. DC generator output. 4. Generator' description Instead of a simple loop, an iron core coil with 1241 turns of O,16mm2 varnished copper ire was used. The iron core and its windings are shown in Fig. 5. The magnetic field used to induce a voltage between the coil terminals was provided by a Figure 7. Three coaxial printed circuit board disks w ith coil on top. 45 Fig. 8 and Fig. 9 illustrate how the rings and collector unit was built in a more comprehensive way.In Fig. 8, a cross-section of this unit is shown, revealing how electrical connections were made: one terminal of the coil was connected to one of the smaller disks and to one of the halves of the larger disk (collector); the other terminal was connected to the other smaller disk and to the ther half of the larger one. Fig. 9 shows a panoramic view of the assembly and the generator outputs responsible electrical load. In order to make the generator operate properly, the DC output brushes positions must be displaced by 1800 from each other.The AC output brushes may be placed anywhere on the respective disks. coil Copper wire Insulator Copper Solder Figure 8. Connecting the coil to the three coaxial printed circuit board disks. power could be easily measured, some sort of mechanical power meter was needed and it was not available. There are always mechanical and elec trical power losses in the process of ransforming mechanical energy into electric energy. Mechanical losses may be reduced by lubricating friction points. The generator was put to rotate at 3000RPM; the measured induced voltage was 1,2V peak-topeak, with a 50Hz frequency. . Conclusions Spinning a wire loop within a uniform magnetic field in a convenient fashion induces a voltage between the loop terminals. Rotation speed influences the induced voltage amplitude and frequency. If an electrical load is connected to the loop terminals, a current will be established in the circuit. The current generated by a basic electrical generator is alternating current. If the generator s intended to supply direct current, it must have a device working as a mechanical rectifier: the collector.A device capable of generating both AC voltage and DC voltage has been presented. A coil attached to a shaft spins within the magnetic field ofa â€Å"U† shaped magnet. Three conveniently designed condu ctive disks allow either with alternating current or direct current. This device is very useful to illustrate the principles of electrical energy generation. It also shows the main similarities and differences between AC and DC generators: the working principle is the same for both machines, but the AC generator has contact rings and the DC enerator has a collector.