There is No universal experience of 'childhood' - it is a construct Essay

There is No universal experience of 'childhood' - it is a construct entirely dependent on patterns of social organisation and cultural conventions Discuss with - Essay Example This is the beginning of shaping a child to think and act like the parent. In this process, children are taught how to behave and how to move within their culture. Depending on how the child is treated they will either develop a strong character and self-esteem or they will develop one that is weak. A child is taught to perceive the world through their parents eyes and they willing accept this teaching. The biggest influence on childhood will be the culture, religion, economic and social aspects of the family. Rodd (1996) says that culture plays a significant role in childhood and it can be the mainstream culture or it can be a subculture (Rodd, p. 31). Shechtman Hiradin and Zina (2003) talked with adolescents in their study to find out whether there was a difference in how these children would disclose about them based on their ethnicity. Their study found that Moslem children were able to disclose easier than Druze children and they thought it may be due to how much acculturation each ethnic group displayed. Druze people re more traditional in their ways and less acculturated to the mainstream than Moslem and Jewish children according to their findings. This information shows that there is some truth to the idea that culture plays a part on how a child learns. It is the opinion of this writer that culture is a very big part of how children accept certain things in their environment. For instance, many children grow up and are abused in their childhood. Often this leads to abusive adults. The culture can also teach a child to love or to hate, to express themselves well or to be introverted and shy. There are a variety of cultural challenges to a child both inside the home and outside because they are constantly being bombarded by cultural situations. Harris (1999) says that what a parent does may not matter to a childs growing up. She gives examples of how one culture (that of the 1950s) taught parents not to spoil their children. Today, parents are

Differences in Teaching Styles Essay Example for Free

Differences in Teaching Styles Essay â€Å"Young children too may die†¦Ã¢â‚¬  (The New England Primer 129). When reading this statement it is difficult to comprehend that this is written in a children’s book. The New England Primer is the book that was used to teach Puritan students to read in the 1700’s. There are many differences in the way that students were taught in the 1700’s and how they are taught today. A few of these differences are; that in the 1700’s, being taught religion was more important than to gain actual knowledge, and learning to have obedience and morals was an important part of a child’s school day, the content of The New England Primer and other modern children’s books, as well as the ultimate reason for children learning to read is altogether different. Religion was the main focus of the reading in The New England Primer. Today, children are taught to read by using a list of ABC’s, and saying, â€Å"A is for Apple, B is for Boy†¦Ã¢â‚¬  and it is made so that it is easier for younger students to understand. The list of ABC’s in The New England Primer has the letter and then a picture next to it, but instead of having a word that would make it easier for the children to understand there is a sentence such as, â€Å"A – In Adam’s Fall/ We Sinned all, B – Thy Life to Mend/ This Book Attend†¦Ã¢â‚¬  (The New England Primer 128) but some were more appealing to the students (Kreilkamp), â€Å"The Cat doth play/ And after flay, Nightengales fing/ In Time of Spring† (The New England Primer 128). The students learned in the book through sin, disobedience, and death, instead of learning through things that children learn through today such as dogs, love, and happiness. All of the ABC’s sentences are about God and the Bible, so there is no room for the child to disagree with any part of the ABC’s. The children read about things such as, God’s Works, Fall of Adam, Jesus, Justification, Adoption, and Sanctification. These are things that are important for a child to learn, but also make it harder for them to read with large words and concepts that are difficult to understand. Children today read about things that interest them and have different reading levels to make learning to read easy and fun. If a child today were handed The New England Primer they probably would not want to read it or may not even have the ability to read it. The Puritan children did not know anything other than The New England Primer, so they did not have anything to compare it to. The children in the 1700’s saw God and Jesus as, â€Å"the avenging father and a forgiving son† (Watters 2) because that is how The New England Primer portrays them. In the time between the 1660’s and the 1690’s, God went from being portrayed as an angry and wrathful God, to being a loving and caring God. (Elliot 13-14) The New England Primer failed to show that shift in beliefs so the children would continue to fear God and obey their parents and elders. The parents wanted the students to have a thorough understanding of God, Jesus, and the Bible, so it was the first thing that they learned and everything was based on this particular concept. The New England Primer was used to teach students to read as well as to teach them to be obedient and to have good morals. It tells the students that Adam and Eve were sinful and disobedient so they were punished by God, but it also says that children are guilty for their own thinking and deserve continued punishment. The children read, â€Å"The Dutiful Child’s Promises†, which is a list of things that a dutiful child does, or strives to do. The children are told to â€Å"honour my Father Mother† and to â€Å"Fear God and honour the King† (The New England Primer 129). The children were also told to follow the Ten Commandments, which were also to be memorized so that God could â€Å"read† them. This shows how fearful and compliant the children are to their parents and to God. The children also were encouraged to memorize â€Å"The Dutiful Child’s Promises† so that they could use it to make correct and obedient decisions. Punishments for the Puritan children were emphasized in the ABC part of The New England Primer, by â€Å"F – The Idol Fool Is whipt at School†. This was an additional warning to the students that they must behave in the classroom or there will be punishments. The punishments in the 1700’s and today are very different, back then teachers could hit their students with rulers, but today teachers may not even raise their voices with students without the risk of losing their jobs. The first theme that you read about in The New England Primer is death, and death is a very heavy topic for children in today’s age for many different reasons. In the 1700’s, children understood death, better than children today, because it surrounded them every day. The hardships that the Puritans faced are nothing like any young student today could possibly understand. Death is understood by the Puritan children, and when The New England Primer says, â€Å"Rachel doth mourn for her fifst born†, the children understand it because they many of them have lost a sibling because of the lack of medical knowledge in the 1700’s. It seems dark and depressing to people today, because today’s society is uncomfortable with talking about death and dying. For the children in the 1700’s it was just a way of life and something that happened every day. The New England Primer emphasized that very point in the Verses of â€Å"The Dutiful Child’s Promise† in saying that death does not only take away the old, but that children can die as well, and so they need to be prepared when they do die to go to Heaven. Children today are getting saved, but they are not doing so to get prepared for death, they are getting ready to serve God with all of their heart and soul. Students today are being taught with the mind set of learning everything they can to reach their own personal goals in life. In the 1700’s the reason for reading was very different from the way that it is today. The parents wanted to children to be able to read so they could read the Bible, not so they could learn about different topics or to read for enjoyment. When educating students today, it is understood that it is the end goal for teachers to help the students get ready to be able to provide a living for themselves with the knowledge that they learn, but in the 1700’s it wasn’t necessary to learn to read for any other reason than the bible because the poems emphasized how to live and act. The New England Primer was â€Å"designed to provide, Spiritual Milk for American Babes† (Anthology of American Literature) and to keep them from being tempted by Satan and other religions that may try and tempt them. The people of the 1700’s believed that there were, â€Å"millions to read, and not one to sin† (Anthology of American Literature), which means that it was believed that the people who read The New England Primer, understood what God wanted them to do and how He wanted them to live, never sinned again, for fear of angering God. The idea of people never sinning again from reading a book is not accurate and students today will read and understand what is going on in the book and be able to enjoy it. The New England Primer was the most important book in teaching Puritan students in the 1700’s to read, but the most important book that they could read was the Bible. The Puritans emphasized their belief in God in every aspect of their lives, especially in teaching their children to e good and kind members of the Puritan community. Teachers of student’s today want to see their students progress and keep learning even after they have learned how to read, because it teaches them about the world that we live on and what is going on outside of their houses and towns. There are many differences between the teachings in the 1700’s and the teachings today, but in the end the important thing is teaching the students to read.

Japan: Social Customs :: essays research papers

The information provided, talks about family traditions, marriage customs, and education in Japan. I think the way marriages are setup in Japan are much different than thus of the United States. Family roles are also very different. In Japan, it is common for newly wed couples to live by themselves until their parents get old. Many couples intend to live with their parents only after spending years all by themselves. However, if the husband is not in a position to support his parents, which means most of the time that he is not the first child of the parents, they don't plan to live with them. With this tendency, the housing industry is prosperous. Increase of the nuclear family is generating a fashion in housing, that is Nisetai-jutaku. The word literally means a "house for two generations". An example of this is: a two-storied house first-floor for older people, second-floor for younger people, one kitchen, one toilet, and sometimes one bathroom. Japanese people love to have a party in Western style, and a Wedding party is of no exception. Almost all wedding halls have a miniature of a Japanese shrine inside, to have a new couple vow their marriage to the Japanese God, as well as many rooms to celebrate their wedding in Western style after the vow. A bride wears a pure-white Japanese Kimono (Shiro-muku) in front of the God at first. Then she changes it to a colorful Kimono at the beginning of the wedding party, then again to a beautiful Western-style in the middle of the party and finally to a pure-white wedding dress (Western-style). Changing clothes in the middle of the party is called oiro-naoshi.However, recently some people prefer the tendency of simplification, so they choose the way in simple styles, sometimes without oiro-naoshi or even without the party itself. Of course, there also exist people who love to have their wedding party even in a bigger way.Japan's school-age children attend school regularly. Attendance is required through the lower level of secondary school. Children begin nursery school when they are about three. At six, they begin elementary school at twelve, middle school. Any student who has completed middle school may enroll in high school, which offers either a technical or a college preparatory course of instruction.

Tourism and it’s negative Effects

While tourism can be a powerful positive force for change in poor countries, it can also be seriously damaging for the local environment and culture. An increase in mass tourism that is not controlled responsibly can ruin areas of natural beauty. com/the-economic-impact-of-tourism/">Tourism can damage coral reefs, pollute beaches and destroy the habitats of wildlife as roads and hotels are built. Ironically, damage to these natural resources is likely to reduce future numbers of visitors. Another negative effect is that the increasing numbers of aeroplane ?ights are a major cause of global warming.A second problem is that the tourist resorts are frequently owned by large Western companies and all too often the pro?ts earned from tourism go straight into the bank accounts of these companies. Moreover, the well-paid managerial positions are often held by foreigners, and the wages given to local hotel employees are usually very low. Where this is the case, very little money enters the l ocal economy at all. By purchasing souvenirs, food and other goods from local people you can help to spread the bene?ts of tourism.Finally, tourism can have an adverse effect on local culture, traditions and the way of life. Large numbers of tourists can undermine traditional beliefs, values and customs and in particular risk commercialising the culture that they ?nd so interesting. And where these tourists are insensitive to local traditions their behaviour can cause great offence. Tourism Fact File  · Tourism employs 250 million people, roughly one in ten of the world's workforce.  · 80% of the people that travel internationally come from the USA, Canada, Japan and 17 European countries, including the UK. · 15 million Britons take package holidays abroad each year.  · The developing world's share of the tourist trade has increased by an average of 9. 5% a year since 1990.  · The amount of money that leaves a destination country (the country where people spend their holid ay) varies from 40% out of India, and 80% out of the Caribbean islands.  · The UN calculates that the amount of water used by an average tourist in 24 hours would be enough to grow rice for an individual for 100 days.  · An 18-hole golf course in a dry country can use as much water as a town of 10,000 people.

Amazon’s Marketing Strategy Essay

Abstract The purpose of this paper is to evaluate the marketing process of online retailer Amazon.com, Inc. Amazon.com provides a number of retail services as well as web and storage services. The corporate strategy framework, as discussed in Cravens & Piercy’s Strategic Marketing text, will be used to examine the background of the company and define its current position. The corporate framework includes the following: (1) corporate vision (2) corporate objectives toward vision (3) resources (4) business composition and (5) business design. The marketing strategy of the company will be reviewed using Cravens & Piercy’s suggested marketing strategy process. To assess the current marketing problems and opportunities, this paper takes a closer look at the company’s current SWOT analysis, provided by GlobalData. In addition, strategic recommendations will be made for the company’s prolonged growth. Amazon Inc. A company’s market driven strategy â€Å"mandates more effective integration of activities and processes that impact customer value† (Cravens & Piercy, 2009). As well as a consistent market driven strategy, an organization must be creative and innovative in order to compete in the global marketplace. Amazon, Inc. has developed an inventive marketing strategy through the use of the Internet. By becoming pioneers in the e-commerce marketplace, the company has transformed retail. Amazon Inc. should evaluate their corporate and marketing strategies to make use of all available resources. The company has experienced some marketing failures but can still take advantage of existing marketing opportunities. In the 9th Edition of the text Strategic Marketing, Cravens & Piercy write, â€Å"corporate strategies are concerned with how the company can achieve its growth objectives in current or new business areas† (Cravens & Piercy, 2009). When building the framework for a co mpetitive corporate strategy, an organization must first decide the corporate vision. During the summer of 1994, Internet usage showed promising growth. A reported statistic of 2,300% yearly growth encouraged Jeff Bezos, then Senior Vice President for D.E. Shaw & Co., to quit his job and concentrate on a way to gainfully use this information. His long term vision for his company was to revolutionize retail by creating â€Å"the  earth’s biggest online retail store, where everyone could buy anything and everything† (Kargar, 2003). To achieve this goal, Bezos conducted market research that led him to Seattle and directed him to choose selling books online as his main focus. The company was launched in 1995 and by the first quarter of 1996 reported sales revenues of $110 million. The company soon changed from a virtual bookstore into a virtual marketplace by entering new markets that included music, movies, electronics, toys, apparel, grocery and others. Years later in 2006 Amazon.com had become what some called a model of â€Å"the next-generation Internet-based business† (Isckia, 2009). That same year the company introduced their new endeavor, Elastic Compute Cloud (EC2), that offered cheap computing power over the Internet. Many believed Bezos’ unconventional wisdom took the company further away from its core vision. However, a closer examination of Bezos creative mindset reveals more of the organization’s well developed corporate philosophy and structure. Moving beyond book selling, the launch of EC2 and Simple Storage Service (S3) are examples of achievements towards the corporate vision. Amazon has been able to implement objectives in the areas of product quality improvement and new-product targets. Cravens and Piercy note that â€Å"a key strategy issue is matching capabilities to market opportunities† (Cravens & Piercy, 2009). Transforming Amazon.com into more than just a retail operation has given the organization the capability to â€Å"compete in different markets, provide significant valued to end user customers, and create barriers t o competitor duplication† (Cravens & Piercy. 2009). With Bezos’ continuous investments in new technological initiatives, investors were concerned about Amazon’s increasing debt and profitability. Kargar reports, â€Å"the company had a weak balance sheet [and] massive negative operating cash flow† (Kargar, 2004). Throughout the company’s financial history there have been many monetary losses. According to Robert D. Hoff and Heather Green, in 2002, â€Å"the company still carried $2.2 billion in long-term debt† (Business Week, 2002). In International Journal of Cases in Electronic Commerce, Pauline Ratnasingham reports that â€Å"Amazon.com shareholders lost 80% of their value in 2000† (Ratnasingham, 2006). Though sales increase rapidly, losses continue to soar as well. Despite the financial failures, in 2006 Bezos’ still believed that his investments would yield big payoffs in later years and that Amazon.com would be a â€Å"meaningful business†¦one day† (Hoff, 2006). As Amazon.com continued to expand, the company’s strategic business units (SBU) consisted of four key divisions: (1) U.S. Books/Music/DVD/Video (2) U.S. Electronics, Tools, and Kitchen (3) Services and (4) International (Ratnasingham, 2006). This business composition makes it easier to focus on separate specific strategies for each unit. The company’s business model also provides a competitive advantage. Amazon benefits from being able to maintain a virtual store front with distribution centers located in low rent areas. In all, a combination of convenience, speed, reliability, discounted pricing, and a wide selection of merchandise creates a synergistic business design that cannot be easily duplicated. When developing Amazon.com’s corporate structure Bezos clearly understood and defined his business strategy. The organization would now need to design and implement a consistent and integrated marketing strategy. An important aspect of Amazon.com’s marketing strategy is their customer-centric approach. Amazon offers lower prices, free shipping, and customer service available 24/7. Also, the customer experience is enhanced through personalized recommendations and customized web pages. The organization’s strength in customer service has been effective in increasing customer loyalty, website traffic, and repeat purchases. Amazon.com uses various marketing techniques that include online advertising, email campaigns, and their Associates Program. The Associates Program, which allows outside websites the ability to make products available to Amazon customers, has proven to be very successful. In 2001 over 700,000 associates were registered for the program. This marketing tool allowed Amazon.com the ability to â€Å"expand its market beyond its own website and concentrate on its strength of order fulfillment and distribution† (Ratnasingham, 2006). Another key aspect of Amazon.com’s marketing strategy is their established strategic relationships with various traditional retailers. These alliances enhance the value offerings of customers, give the company a competitive advantage, and increase the market share for all companies involved. Some of Amazon’s partnerships include Toys ‘R’ Us for toys and video games, the Gap for clothing and Drugstore.com for pharmacy items. The company also has third party arrangements with Target Corporation, Borders Group, Expedia, and others. Amazon profits by providing customers with a diverse array of products while their allies are able to use the technology, services, and  tools of Amazon.com. A significant detail of any organization’s marketing strategy is creativity and innovation. In her article for The Learning Organization, Verna Allee suggests that â€Å"in order to sustain competitive strength and continue growth Western companies need to build innovation into their cultures and structures as an essential condition for value creation† (Allee & Taug, 2006). In 2008, Amazon.com was listed as number 20 in a list of the world’s 25 most innovative companies (Cravens & Piercy, 2009). The new service offering of the EC2 and S3 digital utilities moves the company into competitive opportunities within the software platform marketplace. Bezos’ innovation strategy for Amazon.com includes these five following rules: 1) Measure everything 2) Keep development teams small 3) Don’t be afraid of weird ideas 4) Open up to outsiders 5) Watch customers, not competitors (Hoff, 2006) Amazon.com’s technological advances and Bezos’ forward-thinking has led the company to create ground-breaking products, such as the Kindle and also compete with top online digital music provider Apple ITunes. By encouraging continued innovation, Amazon can secure their place as leaders in Internet-based businesses. Amazon.com is in a position to gain from the various opportunities they have in the e-commerce marketplace. These opportunities include new trends and technological advances. Amazon competes well and has growth in the digital e-book market thanks to their Kindle product. Amazon can continue to invest in technology to sustain profitability. In general, E-commerce is experiencing growth. Amazon.com is in the position to benefit from this rise. The site currently offers payment security, one-click payments, user-friendly features, and other technologies that new web-based businesses will have to compete with. The company also has the opportunity to expand through strategic alliances and acquisitions. For example, GlobalData reports that Amazon.com acquisition of TouchCo earlier this year, â€Å"is expected to bring about cost reduction in the company’s business† (GlobalData, 2010). Overall, Amazon.com employs strong marketing  strategies. GlobalData reports that the company’s emphasis on marketing can be seen in their increased marketing costs in 2009, in comparison with 2008 and 2007 (GlobalData, 2010). However, Amazon.com is faced with some marketing problems. Because the company has a seasonal nature, more shoppers during the holiday seasons, the number of customers accessing the website at one time could cause system interruptions. This could contribute to fulfillment issues and a delay in deliveries. Also, Amazon.com faces the threat of traditional retail stores like Wal-Mart or Barnes & Nobles who now have an online component. Amazon.com now has to compete with companies who have greater brand recognition and more customers. The partnerships the company has made also pose a problem. For example, in 2004 Toys ‘R’ Us bought a case against the company because Toys ‘R’ Us exclusive items were being sold by competitors through Amazon’s website. Also the company suffered increased costs because of their alliance with Drugstore.com. To offset the problems and threats faced by the company, Amazon can benefit from the following strategic recommendations. First, during the off-season Amazon can do aggressive promotional campaigns to include discounts for students and partnerships with university and college professors to be the exclusive vendor for textbooks and suggested reading materials. Also, Amazon’s fulfillment processes should be evaluated to determine what issues are prevalent during the holiday season. Those issues should be addressed and fulfillment centers should be restructured accordingly. The company should re-evaluate their alliances by doing a cost assessment. By determining which costs are insignificant, expenses can be reduced or eliminated. Through the leadership of Jeff Bezos, Amazon.com continues to be the best and first by thinking outside the box. The company has changed the way consumers shop, the way they read, and the way entrepreneurs run their businesses. Bezos accepts his failures, focuses on what works and continues to support new ideas and hopeful initiatives. An evaluation of their marketing and corporate strategies to assess their failures can allow them the ability to make appropriate use of their opportunities. References Cravens, D. W., & Piercy, N. F. (2009). Strategic marketing (9th ed.). New York: McGraw-Hill. Hoff, R.D. (2006). Jeff Bezos’ risky bet. BusinessWeek, 52-58. Retrieved December 14 from ABI/INFORM Global. Hoff, R.D., & Green, H. (2002). How amazon cleared that hurdle: to earn a profit, it cut costsand started growing again. BusinessWeek, (3768), 60-61 Retrieved December 14 from ABI/INFORM Global. Hoff, R.D., Neuborne E., & Green, H. (1998 December). Amazon.com: the wild world of e-commerce: by pioneering – and damn near perfecting – the art of selling online, amazon is redefining retailing. BusinessWeek (3608), 106 Isckia, T. (2009). Amazon’s evolving ecosystem: a cyber-bookstore and application service provider. Canadian Journal of Administrative Sciences, 26(4), 332-343. Retrieved December 17 from ABI/INFORM Global. Kargar, J. (2004). Amazon.com in 2003. Journal of the International Academy for CaseStudies, 10(1), 33-52. Retrieved December 11, 2010 from ABI/INFORM Global. Ratnasingham, P. (2006). A swot analysis for b2c e-commerce: the case of amazon.com. International Journal of Cases in Electro nic Commerce, 2(1), 1-22, Retrieved December11, from ABI/INFORM Global.

The eNotes Blog The Love Lives ofAuthors

The Love Lives ofAuthors Love is dangerous- best to leave it to the experts. Spend your Valentines Day living vicariously through these writers and their passionate love lives. Because lets face it, youd rather be draped in chocolate wrappers than a volatile amour, right? Just me? Lord Byron Image via Mental Floss The 6th Baron Byron was a Romantic with a capital R, but that doesnt mean he was particularly gentlemanly. His first partner in scandal, Lady Caroline Lamb, described him aptly when she professed he was mad, bad, and dangerous to know. Indeed, she was just one of many public conquests that rocked British society, several of which produced children. Only one of these was legitimate, the Honorable Augusta Ada Byron, also known as the  co-creator of the first computer, Ada Lovelace. Others, save for a daughter he had with Mary Shelleys sister, were never proven or recognized by Byron. In essence, he was a cad with a weakness for women, or so we can assume from his poem  Don Juan.  I mean, not even  his own half-sister  was off-limits to him. But still some come to his defense. Poet Katha Pollitt excused Byrons bad boy behavior with an interesting take on his contribution to feminism:  Ã¢â‚¬Å"Byron’s great insight, in an era where women were expected to be placid and insipid (not that they were!), was to see that women were much like men: They wanted sex and went after it eagerly, if secretly.† William Butler Yeats Image via The Poetry Foundation Its never too late to find love, or in Yeats case lust. The Irish poet was already in his fifties when he proposed to and married twenty-five year-old Georgie Hyde-Lees. It only took until their honeymoon for him to regret this decision, though they stayed married for the duration of his life and shared two children. Obviously a pragmatic and forgiving woman, Georgie wrote to her husband,  When you are dead, people will talk about your love affairs, but I shall say nothing, for I will remember how proud you were. Well, she was right: were still talking about his love life almost as much as his poetry, mostly because of the Lolita-esque nature of Yeats infidelities. At the age of sixty-nine Yeats underwent the Steinach operation, a procedure created to renew vigor in older men by increasing hormone production. It seemed to do the trick; for the last five years of his life he found poetic inspiration in the arms of numerous young women.  I find my present weakness made worse by the strange second puberty the operation has given me, the ferment that has come upon my imagination. If I write poetry it will be unlike anything I have done. So I guess were thankful for his lasciviousness?   Ick. W. H. Auden Image via Inside the Apple In 1928 Auden was engaged to be married, to a woman. Such was expected of a closeted gay man of that time. So, in 1929 the poet embarked for a sojourn in Berlin, where he could openly gratify his homosexuality. His goal was to essentially binge until he outgrew such desires, but ten months later nothing had changed except his own view of his sexuality. He returned to England, broke off his engagement, and wrote six love poems in German. His journal of that time, discovered in 1990, reveals a poets typical tormented view of love: He noted in his 1929 journal that he liked to suffer and that he regarded suffering as part of his identity as an artist. He also observed in the journal that the torment of his homosexuality was, for him, one of its attractions; he associated mutual love with despair. Most likely, Audens views on Valentines Day and requited love wouldnt gel with your own. However, there is one thought from his diary I petition us all to take to heart: all bureaucrats should be obliged to prove that they have a happy love-life, and immigration officials most of all. H. G. Wells Image via The Victorian Web The writer of the famous  War of the Worlds appeared to also suffer a war with women, at least one woman in particular. Wells was married to his cousin Isabel when he fell in love with one of his students, Amy Catherine Robbins. Yet, this was not his greatest upset. After divorcing Isabel the author married Amy, who agreed to an open marriage. Wells proceeded to carry on affairs with prominent women, some of whom were activists and novelists. He had a daughter out of wedlock with the writer Amber Reeves and then a son with the feminist Rebecca West, who was twenty-six years younger than him, only nineteen at the time. She apparently expected Wells to leave his wife for her, which didnt happen, and their tempestuous love affair ended with an angry letter from West: When you said, â€Å"You’ve been talking unwisely, Rebecca,† you said it with a certain brightness: you felt that you had really caught me at it. I don’t think you’re right about this. But I know you will derive immense satisfaction from thinking of me as an unbalanced young female who flopped about in your drawing-room in an unnecessary heart-attack. Translation: Youre a jerk for making me feel like a crazy person. Basically the old-fashioned version of a break-up text. In his autobiography Wells confessed,  I was never a great amorist, though I have loved several people very deeply. Lets hope it soothed the burn. Want more author-related Valentines Day posts? Check out our most popular articles on the Top Ten Love Letters of Writers  and Top Ten Love Lines from Literature for Your Valentine.

Monetary Policy and the Economy essays

Monetary Policy and the Economy essays Using the tools of monetary policy, the Federal Reserve can affect the volume of money and credit and their price-interest rates. In this way, it influences employment, output, and the general level of prices. THE FEDERAL RESERVE ACT LAYS OUT the goals of monetary policy. It specifies that, in conducting monetary policy, the Federal Reserve System and the Federal Open Market Committee should seek to promote effectively the goals of maximum employment, stable prices, and moderate long-term interest rates. Many analysts believe that the central bank should focus primarily on achieving price stability. A stable level of prices appears to be the condition most conducive to maximum sustained output and employment and to moderate long-term interest rates; in such circumstances, the prices of goods, materials, and services are undistorted by inflation and thus can serve as clearer signals and guides for the efficient allocation of resources. Also, a background of stable prices is thought to encourage saving and, indirectly, capital formation because it prevents the erosion of asset values by unanticipated inflation. However, policymakers must consider the long- and short-term effects of achieving any one goal. For example, in the long run, price stability complements efforts to achieve maximum output and employment; but in the short run, some tension can arise between efforts to reduce inflation and efforts to maximize employment and output. At times, the economy is faced with adverse supply shocks, such as a bad agricultural harvest or a disruption in the supply of oil, which put upward pressure on prices and downward pressure on output and employment. In these circum-stances, makers of monetary policy must decide the extent to which they should focus on defusing price pressures or on cushioning the loss of output and employment. At other times, policymakers may be concerned that the publics expectation of more infl...

Create a Best Visual Essay in 2018 [BEST PRACTICE]

Create a Best Visual Essay in 2018 [BEST PRACTICE] What Does Creating a Visual Essay Imply? To begin with, a visual assay appears to stand out of the crowd. Actually, it is a totally different assignment from a classic essay. The point is that while covering this written task, you shouldn’t write anything at all except for some short informative statements! In fact, this academic assignment requires to express your thoughts on this or that topic using: pictures images visuals Moreover, to present your point of view on the required topic you may combine all above-mentioned means with some short informative statements related to the theme. Some Fresh Ideas on Handling Visual Assignments Clearly, the most difficult and challenging step while fulfilling this task is finding really suitable and gripping visuals, pictures and images to use. Obviously, it presumes using creative approach and skills. In other words, ability to generate fresh ideas seems to be a determinant factor on your road to success. In search of inspiration and great ideas we recommend you analyze the ready-made visual assignments composed by other students. Besides, you are welcome to upload free essay templates at our site. Visual Essay Tools You May Use Of course, introducing your ideas to the audience is one of the crucial points of getting a positive grade for this task. To make a presentation of your visual paper more eye-catching, pleasant and what is more important, – efficient, you may use the following helpful tools: Adobe Flash PowerPoint Microsoft Word Photoshop Windows Movie Maker Imovie We expect these tools to be fruitful for you. Make the most out of them and you’ll be impressed by results. Wholesome Recommendations on Composing a Visual Essay Are there any clear effective hints, which can help you to create your visual paper with ease? Of course, there are! And you shouldn’t seek for them, because they are posted below: Surf the web and use camera to collect the data for your essay. Incorporate thought provoking visuals, images and pictures in your paper. To make your presentation more griping feel free to use graphs, various charts and bars. All the data you want to use should be up-to-date and relevant. Don’t forget about numerous visuals aids while defending your paper. Show your paper to your relatives of friends before submitting it. They may give you favorable advice as well. Competent Help with Visual Essays Still feel a little bit frustrated because of these visual assignments? Don’t fall into despair! There is always a way out from any tough situation! Visual papers are not an exception. If you don’t feel like creating papers on your own, feel comfortable to receive competent help from expert writers online. Order proficient assistance from WritingBee.com and we will pick the finest certified author for you.

Why has the UK's productivity lagged behind that of its major Article

Why has the UK's productivity lagged behind that of its major competitors and what can be done to improve the productivity and competitiveness of the UK economy - Article Example A person such as the Exchequer Gordon Brown’s UK Chancellor, in his speeches, productivity is his main theme. However, despite the fact that UK is lagging, it is far much at the forefront in terms of labor and capital markets structural amendments. To come up to the analysis that UK’s productivity is low, examination of the economy’s six sectors took place and the results indicated that it’s true that output was low. Those sectors examined are; car production, retailing software, telecoms, food processing and hotels. McKinsey Global Institute a global most highly regarded management consulting firm is the one that conducted the research regarding the matter. UK should address several issues to increase its output. One of the major concerns is increasing expenditure to boost high levels of research and development and reducing diversion of resources towards the public sector which is less productive. It is vital for the state to increase its level of investment despite the fact that the Crash of Lehman Brothers led damaged the country’s economy in the year 2008 because many other firms held off from investing in the modern, most efficient technology and processes. Businesses should enhance their levels of innovation, come up with good labor relations, improve their technology usage and adopt modern technology to ensure that businesses stay for long in their field. The government should come up with extra reforms in its business regulations in order to boost investment thus increasing productivity of the

Effects of ADHD Medication and Student Performance Essay

Effects of ADHD Medication and Student Performance - Essay Example A baseline will be established for each student prior to the study based on the pretests. The study will be conducted for four months during the academic year. This experimental research design utilizes quantitative methodology with a randomized pretest-posttest control group and treatment group. The research will include 60 students from a fourth grade elementary school who will be randomly assigned to either an experimental treatment or control group, consisting of 30 students in each group. Table of Contents Main Body I. Problem to be investigated 4-5 A. Purpose of the study 4 a. Assumptions 4 B. Justification of the study 5 C. Research question and null hypothesis 5 D. Definition of Terms 6 a. Constitutive Definitions 6 b. Operational Definitions 6 E. Brief overview of the study 7 II. Background and review of related literature 8 A. Theory 9 B. Studies directly related 9-10 C. Studies tangentially related 10-11 References 12 Attention deficit hyperactivity disorder or ADHD is a d isorder characterized by lack of attention, hyperactivity, and impulsive behavior (PubMed Health, 2011). Due to these characteristics, children with ADHD have difficulty in school, possibly due to multiple factors. Children with ADHD may be unable to keep up with the lessons due to lack of concentration, or they may be seen as disruptive by their teachers. Consequently, they may be deemed unfit to progress in their schooling and be retained in their current grade, which is something that may have grave consequences on the children’s educational and global development. Parents and teachers must recognize that ADHD is not something to be taken against a child, but a disorder that can be overcome with proper and adequate pharmacologic and non-pharmacologic interventions. Teaching interventions that are more suitable for children with ADHD may help enormously with the children’s proper education and development. Poor outcomes may also be seen in children diagnosed with ADH D who do not receive medication. The goal of this research project is to determine the effectiveness of pharmacologic medication in improving academic outcomes of children diagnosed with ADHD. In the following sections, topics related to the issues discussed above will be addressed. The sections include: the purpose of the study and related assumptions, justification of the study, research question(s) and hypothesis, definition of terms, a brief overview of the study, and a conclusion. Problem to be Investigated The problem to be investigated is determining effective solutions to ensure students diagnosed with ADHD do not suffer academically. Stimulant medication has been suggested as one such solution. Purpose of the Study The purpose of the study is to determine the effectiveness of ADHD stimulant medication on improving the academic achievement of students diagnosed with ADHD. Assumptions The following assumptions will be made during the study: 1. This sample is representative of the population of elementary students. 2. The instrument used will measure the desired outcome of the research study. 3. The predictive information from this study will be used by counselors, teachers and parents. Justification of the Study Children who are diagnosed often exhibit problem behaviors in the classroom such as inattentiveness,

What causes structural unemployment Essay Example | Topics and Well Written Essays - 1500 words

What causes structural unemployment - Essay Example In most cases, unemployment occurs when the economy in the recession. Globally, more than 200 million people are unemployed which is equivalent to 6% of the global workforce. There are different types of unemployment. These include classical unemployment, cyclical unemployment, structural unemployment, frictional unemployment and hidden unemployment. This paper seeks to discuss about the causes of structural unemployment as well as the ways of dealing with this kind of unemployment. Structural unemployment is defined as a type of unemployment whereby at a given wage level, the labour demanded is lower that the labor supplied. This happens when there is a mismatch between the number of jobs available in the economy and the number of people who are willing to work (Romer, 2011). The mismatch may occur if the unemployed individuals lack the necessary skills as needed by the organizations or they may be residing in different parts of the country far from where the job opportunities are available. Being one of the permanent types of unemployment, most economists argue that improvement on causes of structural unemployment can only take place in the long run. Based on the changing level of technology and obsolescence of certain technology, some experts and systems become of less importance (Ford, 2009). For example, with the emergence of modern forms of printing by use of computers, the use typesetters became insignificance. Another scenario of structural unemployment can be indicated when the economy experience an increase in the level efficiency. In most cases, when any of the economy sectors has high level of efficiency, the number of workers required goes down. For example, by mechanizing the work in the agricultural sector, few employees are needed to carry out the duties in the sector. This implies that some individuals who have qualification in agricultural related

Bless Me, Ultima character analysis Essay Example | Topics and Well Written Essays - 500 words

Bless Me, Ultima character analysis - Essay Example That is why of all her traits, I will focus on Ultima’s firm belief in balance which made her character some sort of a bridge in the problematic conflict of belief systems in the story. My analysis of Ultima starts with her role as a curandera as it reflects some form of universal principle. A shaman or the spiritual leader in a community is useful and performs an important function in authentic culture. She can resort to dreams and visions for help and guidance but she can also resort to the use medical arts with her herbal remedies and her vast experience in healing. Indeed, Ultima is adamant that disharmony and imbalance cause a disruption of health while her approach to healing is aimed at achieving a certain oneness and harmony with nature. Let me begin at the beginning. I do not mean the beginning that was in my dreams and the stories they whispered to me about my birth and the people of my father and mother, and my three brothers – but the beginning that came with Ultima. (Anaya 1991, 1) Anaya also attributes to Ultima, on one the hand the mythical Good Earth Mother and the religious Virgin of Guadalupe, on the other. In the novel, the Good Earth Mother often appears in Antonio’s dreams while the Virgin of Guadalupe is her mother’s spiritual protector. While they both hail from differing establishments they both represent one archetypal feminine principle – the intuitive, loving, life affirming protector and nurturer. Ultima’s character as presented showed that belief systems cannot be always mutually exclusive. Ultima as wise, complex and mysterious stemmed from her openness to receive, understand, assimilate and balance values that do not merely come from a single source, cultural grouping or belief. That is why she is tolerant and understanding as one of her main teachings to Antonio emphasized that those different

Habermas the Public Sphere Essay Example | Topics and Well Written Essays - 1000 words

Habermas the Public Sphere - Essay Example 1-13). According to many political theorists, the public sphere is an important entity for a strong democracy. The public and the private spheres acquired a clear distinction in the 17th and 18th century. The public sphere usually consists of informal citizen discussions and deliberations that lead to the formation of a public opinion which is rational enough to guide and influence political systems. Habermas has given a complete outline of the public sphere in The Structural Transformation of the Public Sphere: An Inquiry into a Category of Bourgeois Society. (1989). This piece of work outlines the public sphere critical theory in a systematically developed manner (Dahlgren, 1995, p. 44). The public sphere thus develops from the realms of public authority as well as private relations. The private relations may involve the family and the civil society at large. The private individuals, therefore, come together to form the public sphere. They are driven by the notion of speech without censorship as well as the desire for unified reasoning. According to Habermas, therefore, the public sphere involves both historical economic and political concerns. He continues to explain that every communication contains a communicative action which is oriented towards an agreement. Whenever a matter concerning living together as a people with differences is debated, the public sphere is always constituted. The public sphere became more of a commercial and entertainment entity rather than its conserving its political character. The shift from the original character to other commercialized versions is documented in the press. Habermas, therefore, looks at the integration of literature and journalism as well as the role played by mass media. The public sphere was also affected by the emergence of mass media. The apparent evolution of the communications environment has made the public sphere to change to a platform for advertisements. As a result of these, there emerges a new class of participants such as public relations practitioners (Thompson, 1993, p. 67). Democracy, according to Habermas, is founded on the world of life. It is this world of life that enables free communication between different people. It also drives people into pursuing private and individual interests as opposed to common goals in life. The media plays a crucial role in any democracy. This comes easier, of course, if the environment is right. Such an environment is one which consists of the requisite skills that enable democratic reporting. The media is most of the time flooded with advertisements that target some individual tastes. The information that is presented is also based on the pre-existing views. There should, therefore, be mechanisms which check for public accountability as well as professionalism in media operations. One of the characteristics that identify a democracy is the independence of the media. This is strengthened by the financial viability of the media organizatio ns. Financial strength ensures that the media operates in an environment free of external influences, especially political influences (Hallin, 1994, p.12). The media is also an essential for checking the political system when that system is unable to meet the social expectations. The media is, however, not expected to entertain political bias or partisan reporting at all. Accessibility of the media

Bless Me, Ultima character analysis Essay Example | Topics and Well Written Essays - 500 words

Bless Me, Ultima character analysis - Essay Example That is why of all her traits, I will focus on Ultima’s firm belief in balance which made her character some sort of a bridge in the problematic conflict of belief systems in the story. My analysis of Ultima starts with her role as a curandera as it reflects some form of universal principle. A shaman or the spiritual leader in a community is useful and performs an important function in authentic culture. She can resort to dreams and visions for help and guidance but she can also resort to the use medical arts with her herbal remedies and her vast experience in healing. Indeed, Ultima is adamant that disharmony and imbalance cause a disruption of health while her approach to healing is aimed at achieving a certain oneness and harmony with nature. Let me begin at the beginning. I do not mean the beginning that was in my dreams and the stories they whispered to me about my birth and the people of my father and mother, and my three brothers – but the beginning that came with Ultima. (Anaya 1991, 1) Anaya also attributes to Ultima, on one the hand the mythical Good Earth Mother and the religious Virgin of Guadalupe, on the other. In the novel, the Good Earth Mother often appears in Antonio’s dreams while the Virgin of Guadalupe is her mother’s spiritual protector. While they both hail from differing establishments they both represent one archetypal feminine principle – the intuitive, loving, life affirming protector and nurturer. Ultima’s character as presented showed that belief systems cannot be always mutually exclusive. Ultima as wise, complex and mysterious stemmed from her openness to receive, understand, assimilate and balance values that do not merely come from a single source, cultural grouping or belief. That is why she is tolerant and understanding as one of her main teachings to Antonio emphasized that those different

Career Goal Case Study Example | Topics and Well Written Essays - 500 words

Career Goal - Case Study Example A student learning business must have good analytical abilities, solid mathematical understanding, good communication skills, and the ability to identify problems and find solutions. Accounting is the discipline in business dedicated to identifying, tracking, recording and analyzing economy activity. The information is tracked in an accounting information system. In order for a person to succeed in this type of work the individual must be good following specific procedures and algorithms to perform their job duties. The specialty I desired to study at the graduate level is international finance. Wall Street has always opened up my curiosity. To me Wall Street is the place to be as a finance enthusiast, on the other side of the hemisphere the city of London is a place were high level financial activity is taking place right now. The stock market in both these cities is a main driver of economic activity. The investors in these areas of the world now know exactly how the information involving reporting of financial information will look like since in Europe public must utilize international financial reporting standards while in the United States public entities must follow the general accepted accounting principles. According to Salary.com the median starting salary for an Accountant

7 Days of Prayers for the Souls in Purgatory Essay Example for Free

7 Days of Prayers for the Souls in Purgatory Essay PREPARATORY PRAYER My Jesus, by the sorrows You suffered in Your agony in the Garden, in Your scourging and crowning with thorns, in Your journey to Calvary, in Your crucifixion and death, have mercy on the souls in purgatory, and especially on those that are most forsaken; deliver them from the torments they endure; call them and admit them to Your most sweet embrace in paradise, where You live with the Father and the Holy Spirit, one God, for ever and ever. Amen See more: Homeless satire essay Prayers from The Raccolta (Here say the prayer for the day) 0ur Father Our Father in Heaven, Your Kingdom come; Your will be done on earth, as it is in Heaven. Give us this day our daily bread; and forgive us our sins, as we forgive those who sin against us; and lead us not into temptation, but deliver us from evil. Amen. Hail Mary Hail Mary, full of grace, the Lord is with you; blessed are you among women; and blessed is the fruit of your womb, Jesus. Holy Mary, Mother of God, pray for us, sinners, now and at the hour of our death. Amen. Eternal Rest Eternal rest, grant unto them, O Lord; and let perpetual light shine upon them. May they rest in peace. Amen. Concluding Prayer Merciful Father, hear our prayers and console us. As we renew our faith in Your Son, whom You raised from the dead, strengthen our hope that all our departed brothers and sisters will share in His resurrection, who lives and reigns with You and the Holy Spirit, one God, for ever and ever. Amen. SUNDAY O Lord God omnipotent, I beseech You by the Precious Blood, which Your divine Son Jesus shed in the Garden, deliver the souls in purgatory, and especially that one which is the most forsaken of all, and bring it into Your glory, where it may praise and bless You forever. Amen. Our Father, Hail Mary, Eternal rest, etc. MONDAY O Lord God omnipotent, I beseech You by the Precious Blood, which Your divine Son Jesus shed in His cruel scourging, deliver the souls in purgatory, and among them all, especially that soul which is nearest to its entrance into Your glory, that it may soon begin to praise You and bless You forever. Amen. Our Father, Hail Mary, Eternal rest, etc. TUESDAY O Lord God omnipotent, I beseech You by the Precious Blood of Your divine Son Jesus that was shed in His bitter crowning with thorns, deliver the souls in purgatory, and among them all, particularly that soul which is in the greatest need of our prayers, in order that it may not long be delayed in praising You in Your glory and blessing You forever. Amen. Our Father, Hail Mary, Eternal rest, etc. WEDNESDAY O Lord God omnipotent, I beseech You by the Precious Blood of Your divine Son Jesus that was shed in the streets of Jerusalem while He carried on His sacred shoulders the heavy burden of the Cross, deliver the souls in purgatory and especially that one which is richest in merits in Your sight, so that, having soon attained the high place in glory to which it is destined, it may praise You triumphantly and bless You forever. Amen. Our Father, Hail Mary, Eternal rest, etc. THURSDAY O Lord God omnipotent, I beseech You by the Precious Body and Blood of Your divine Son Jesus, which He Himself on the night before His Passion gave as meat and drink to His beloved Apostles and bequeathed to His Holy Church to be the perpetual Sacrifice and life-giving nourishment of His faithful people, deliver the souls in purgatory, but most of all, that soul which was most devoted to this Mystery of infinite love, in order that it may praise You therefore, together with Your divine Son and the Holy Spirit in Your glory forever. Amen. Our Father, Hail Mary, Eternal rest, etc. FRIDAY O Lord God omnipotent, I beseech You by the Precious Blood which Jesus Your divine Son did shed this day upon the tree of the Cross, especially from His sacred Hands and Feet, deliver the souls in purgatory, and particularly that soul for whom I am most bound to pray, in order that I may not be the cause which hinders You from admitting it quickly to the possession of Your glory where it may praise You and bless You for evermore. Amen. Our Father, Hail Mary, Eternal rest, etc. SATURDAY O Lord God omnipotent, I beseech You by the Precious Blood which gushed forth from the sacred Side of Your divine Son Jesus in the presence and to the great sorrow of His most holy Mother, deliver the souls in purgatory and among them all especially that soul which has been most devout to this noble Lady, that it may come quickly into Your glory, there to praise You in her, and her in You through all the ages. Amen. Our Father, Hail Mary, Eternal rest, etc.

Breastfeeding: Advantages and Disadvantages

Breastfeeding: Advantages and Disadvantages This essay is potentially vast in its scope as the advantages and disadvantages of breastfeeding can vary enormously depending on which authority one chooses to consult. (1) We shall therefore take an overview and present the generally accepted arguments in this area. There is a substantial evidence base for the benefits of breastfeeding for not only the infant, but also the mother, the families and society as a whole. (2). The benefits are not only nutritional, but cover other areas such as development, immunity, psychological well-being, overall health risks, social and environmental areas (3) Human milk is widely recommended as the food of choice for the otherwise healthy full-term newborn. Apart from providing the optimal nutrition it contains a number of cellular and humoral components such as phagocytes, immunocompetant cells, immunoglobulins and hormones and also plays a (as yet, not fully defined) role in promoting intestinal mucosal maturation. (4) Because of these (and other) considerations, the World Health Organisation recommends exclusive breastfeeding for at least the first six months of life. (5) There is widespread evidence that the trend towards universal breastfeeding is increasing (viz. 6) in most of the developed countries, Fewtrell gives a global figure of 2% per year. but studies show that this trend is not equal across all socio-economic and demographic groups. If we specifically consider the UK situation then we can show that the commencement of breastfeeding is equal in the working and non-working mothers groups, although if one considers the situation of how many mothers are still breastfeeding at six months post partum, the incidence in the working mothers group is less than half that in the non-working group. (7) What then is the evidence base for the benefits of breastfeeding? In addressing this question we shall confine our comments to those relevant to the developed world. If we consider the Kramer study, which compared the benefits of continued breastfeeding from 3 months to 6 months, the authors were able to demonstrate that the additional 3 months produced benefits in terms of greater weight gain, greater growth (length) together with a reduced incidence of gastrointestinal infection. (8) In absolute terms however, the benefits of breastfeeding over formula milks (or cows milk) is much greater. A huge number of potential childhood infections have been demonstrated to have a lower incidence in the breastfed child including bacterial meningitis, diarrhoea, respiratory tract infections, otitis media, urinary tract infections (9) as well as less common entities such as necrotising enetrocolitis (10). It is also significant that the all-cause mortality rates are 21% less in breast fed infants. We should note that this figure, although accurate, is misleading, as many high risk babies are not breast fed because of their intercurrent problems. (11) Apart from infections, many other health benefits can be demonstrated. There is a reduction in the incidence in sudden infant death syndrome under the age of 1 yr. (12). Diabetes (Type I and Type II) is less common amongst breastfed babies (in later life) as are the incidences of conditions such as lymphoma, leukaemia and Hodgkin’s disease. (13). Breastfeeding tends to be associated with a lower incidence of obesity, hypercholesterolaemia and asthma. (14) There is a slightly weaker evidence base to support the benefit of breastfeeding in terms of neurological development. Some authorities suggest that it can improve cognitive development. (15) and it may also reduce the perception of some painful stimuli. (16) In addition to benefits for the child, there are also a number of demonstrable benefits for the mother who breastfeeds. If suckling occurs at the time of birth, the resultant release of oxytocin reduces the incidence of post partum haemorrhage and increases the speed of uterine involution. (17). In the period after the birth, breastfeeding reduces both fertility and menstrual loss, it facilitates a return to pre-pregnancy weight, it reduces the risk of both ovarian and breast cancer (18) and may well reduce the incidence of osteoporotic fractured hips (19) In the opening segment of this essay we alluded to the benefits to the community as a whole. These can be defined in terms or reduced health costs to the community by virtue of the protective effects of breastfeeding. There are also less definable benefits in terms of reduced employee absenteeism. Some authorities have gone as far as to point to the environmental benefits of reduction in energy expenditure on production, distribution and disposal of formula feeds and their packaging. (20) Thus far we have considered the positive benefits of breastfeeding but in order to provide a balanced argument, we should also consider the disadvantages. The pre-term infant or severely underweight or ill baby has special needs and there are a number of reasons why they should not be breastfed. The pre-term infant has immature physiological systems and the kidneys may not be able to handle the osmotic gradients that are required to excrete the amount of fluid necessary to remove the amount of nutritional load required for adequate growth. This may result in respiratory problems and exacerbation of any pre-existing cardiac conditions (viz. patent ductus arteriosus). For this reason, most pre-term infant are electively parentrally fed and then weaned onto enteral feeding when their gastrointestinal tract and other physiological systems are mature enough to handle the fluid load. (21) If the mother is ill or has a potentially communicable illness such as HIV/AIDS or TB, then breastfeeding is contraindicated, as it is in conditions when certain drugs (both medicinal and recreational) are taken by the mother. (22). We should also record that the evidence for HIV/AIDS spread is not secure, as some studies have suggested that breastfeeding actually confers a degree of protection against HIV/AIDS for the child. This is still an area of considerable debate. (23) It is also clear from an examination of the literature on the subject, that there is a great deal of misinformation on the subject of breastfeeding in the popular press (and to a lesser extent in the medical press). Breastfeeding is not contraindicated in conditions such as Hepatitis B or C +ve. (24). Most febrile conditions are not a contraindication to breastfeeding as the maternal immune response will be passively given to the child in any event. Some authorities suggest that tobacco smoking is a contraindication to breastfeeding. If we remove considerations of general health from the consideration, there is no reason why tobacco smoke should be considered a bar to breastfeeding as such. (it clearly may be ill-advised however) (25). Some authorities suggest on theoretical grounds that breastfeeding should be suspended during the period of physiological jaundice of the newborn. A number of recent studies have shown that this is not necessary and may cause insurmountable difficulties in rehabilitation-establishing breastfeeding after the event. (26) In essence, within the scope of the exclusions referred to above, healthcare professionals should actively encourage and support mothers in their ability to breastfeed their offspring. In doing so, one should always consider the autonomy of the mother (27) and attempt to provide empowerment and education in order to facilitate the best result rather than compulsion or emotional blackmail. (28). This should help to ensure the maximum possible take up of breastfeeding from mothers who have been able to make a fully informed decision. If direct breastfeeding is not possible, then, generally speaking, expressed breast milk is the preferred substitute. In this essay we do not presume to have covered anything like an exhaustive presentation of the arguments, but there is no doubt, from an overview of the evidence base on the subject, that in the vast majority of cases, both mother and child will derive substantial benefits from being able to breast feed for at least the first six months of life. References (1) Duerbeck N B (1998) Breast-feeding: what you should know so you can talk to your patients. Comp Ther 1998 ; 24 : 310 318 (2) Kramer M S, Chalmers B, Hodnett E D, et al. (2001) Promotion of Breastfeeding Intervention Trial (PROBIT): a randomized trial in the Republic of Belarus. JAMA. 2001 ; 285 : 413 – 420 (3) Schanler R J. (2001) The use of human milk for premature infants. Pediatr Clin North Am. 2001 ; 48 : 207 – 219 (4) Margolis L H and J. B. Schwartz (2000) The Relationship Between the Timing of Maternal Postpartum Hospital Discharge and Breastfeeding. J Hum Lact, May 1, 2000 ; 16 (2) : 121 128. (5) Fewtrell M S , J. B Morgan, C. Duggan, G. Gunnlaugsson, P. L Hibberd, A. Lucas, and R. E Klein man (2007) Optimal duration of exclusive breastfeeding: what is the evidence to support current recommendations? Am. J. Clinical Nutrition, February 1, 2007 ; 85 (2) : 635S 638S. (6) Bonuck K A, K. Freeman, and M. Trombley (2006) Randomized controlled trial of a prenatal and postnatal lactation consultant intervention on infant health care use. Arch Pediatr Adolesc Med, September 1, 2006 ; 160 (9) : 953 960. (7) Kramer M S, Kakuma R. (2001) The Optimal Duration of Exclusive Breastfeeding. Geneva, Switzerland: World Health Organization ; 2001 (8) Kramer M S , Guo T, Platt R W et al. (2003) Infant growth and health outcomes associated with 3 compared with 6 mo of exclusive breastfeeding. American Journal of Clinical Nutrition, Vol. 78, No. 2, 291 295, August 2003 (9) Heinig M J. (2001) Host defense benefits of breastfeeding for the infant. Effect of breastfeeding duration and exclusivity. Pediatr Clin North Am. 2001 ; 48 : 105 –123 (10) Dewey K G, Heinig M J, Nommsen-Rivers L A. (1995) Differences in morbidity between breast-fed and formula-fed infants. J Pediatr. 1995 ;126 : 696 – 702 (11) Chen A, Rogan W J. (2004) Breastfeeding and the risk of postneonatal death in the United States. Pediatrics. 2004 ;113 (5) (12) Horne R S, Parslow P M, Ferens D, Watts A M, Adamson T M. (2004) Comparison of evoked arousability in breast and formula fed infants. Arch Dis Child. 2004 ; 89 (1) : 22 –25 (13) Davis M K. (1998) Review of the evidence for an association between infant feeding and childhood cancer. Int J Cancer Suppl. 1998 ; 11 : 29 – 33 (14) Toschke A M, Vignerova J, Lhotska L, Osancova K, Koletzko B, von Kries R. (2002) Overweight and obesity in 6- to 14-year old Czech children in 1991: protective effect of breast-feeding. J Pediatr. 2002 ; 141 : 764 – 769 (15) Horwood L J, Darlow B A, Mogridge N. (2001) Breast milk feeding and cognitive ability at 7–8 years. Arch Dis Child Fetal Neonatal Ed. 2001 ; 84 : F23 – F27 (16) Carbajal R, Veerapen S, Couderc S, Jugie M, Ville Y. (2003) Analgesic effect of breast feeding in term neonates: randomized controlled trial. BMJ. 2003 ; 326 : 13 (17) Labbok M H. (2001) Effects of breastfeeding on the mother. Pediatr Clin North Am. 2001 ; 48 : 143 – 158 (18) Rosenblatt K A, Thomas D B. (1993) Lactation and the risk of epithelial ovarian cancer. WHO Collaborative Study of Neoplasia and Steroid contraceptives. Int J Epidemiol. 1993 ; 22 : 192 – 197 (19) Paton L M, Alexander J L, Nowson C A, et al. (2003) Pregnancy and lactation have no long-term deleterious effect on measures of bone mineral in healthy women: a twin study. Am J Clin Nutr. 2003 ; 77 : 707 – 714 (20) Jarosz L A. (1993) Breast-feeding versus formula: cost comparison. Hawaii Med J. 1993 ; 52 : 14 – 18 (21) Denne, S. C., Karn, C. A., Ahlrichs, J. A., Dorotheo, A. R., Wang, J. Liechty, E. A. (1996) Proteolysis and phenylalanine hydroxylation in response to parenteral nutrition in extremely premature and normal newborns. J. Clin. Invest 97 : 746 -754 (22) Read J S; (2003) American Academy of Pediatrics, Committee on Pediatric AIDS. Human milk, breastfeeding, and transmission of human immunodeficiency virus type 1 in the United States. Pediatrics. 2003 ; 112 : 1196 – 1205 (23) Coutsoudis A, Rollins N. (2003) Breast-feeding and HIV transmission: the jury is still out. J Pediatr Gastroenterol Nutr. 2003 ; 36 : 434 – 442 (24) Pickering : (2003) American Academy of Pediatrics. Transmission of infectious agents via human milk. In: Pickering LK, ed. Red Book: 2003 Report of the Committee on Infectious Diseases. 26th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2003 : 118 – 121 (25) American Academy of Pediatrics, (2001) Committee on Drugs. Transfer of drugs and other chemicals into human milk. Pediatrics. 2001 ; 108 : 776 – 789 (26) American Academy of Pediatrics, (2004) Subcommittee on Hyperbilirubinemia. Management of hyperbilirubinemia in the newborn infant 35 or more weeks of gestation. Pediatrics. 2004 ; 114 : 297 – 316 (27) Sines D (1995) Impaired autonomy: the challenge of caring. Journal of Clinical Nursing 4 (2) 109 -115. (28) Marinker M.(1997) From compliance to concordance: achieving shared goals in medicine taking. BMJ 1997 ; 314 : 747 – 8. ############################################################### 12.05.07 PDG Word count 2,183 Polycrystalline Ceramics: Sub Grain Structure Polycrystalline Ceramics: Sub Grain Structure Pure un-doped zirconia is a polymorph which has three allotropes namely: Monoclinic, Tetragonal and finally Cubic. These phases tend to transform into each other when exposed to certain temperature ranges and such transformation is important for the processing and mechanical properties of zirconia. The monoclinic phase of pure un-doped zirconia is stable at room temperature and remains so up to about 11700C, where it then transforms into tetragonal phase. It becomes stable tetragonal at this temperature and remains so up to 23700C, where it turns to cubic. The cubic phase occurs up to the melting temperature of 26800C. Monoclinic phase The monoclinic form also referred to as baddeleyite, is a thermodynamically stable phase at a temperature range between room temperature and approximately 9500C. It contains four ZrO2 molecules per unit cell and has a space group of P21/c. Figure 2.1 shows the lattice parameter of monoclinic form. Its structure is described as a distorted fluorite (CaF2 structure). It is difficult to define the crystal structure of monoclinic zirconia because of its complexity as well as the problem of making a monoclinic single crystal with the satisfactory qualities due to: micro-cracking, low purity, twinning and disproportionate solid solution formation. Tetragonal phase This is a high temperature phase (t) firstly discovered by a group of scientist during its transformation from the lower temperature monoclinic phase over a temperature of about 11500C. Figure 2.1 shows the lattice parameter of tetragonal form. The structure is similar to that of monoclinic polymorph in the sense that it is also distorted CaF2 structure. Hence, tetragonal zirconia (t-ZrO2) can be described using the face centred tetragonal Bravais lattice as oppose to the body centred tetragonal lattice, that contains a unit cell with volume twice the size of the primitive cell. (3) Figure 2.2b shows a simple schematic of a tetragonal unit cell. Its structure comprises of eight oxygen ions surrounding a zirconium ion, with half at a distance of 0.2455nm forming an elongated tetrahedron and the remaining four are at a distance of 0.2065 forming a flattened tetrahedron (the elongated and flattened tetrahedron are rotated 900 to each other). The transformation from tetragonal to monocli nic can start (Ts) and finish (Ts) over a range of temperatures. This reaction can be measured using the following experimental techniques: DTA, XRD and dilatometry. (3) Cubic phase Unlike the other structures, the cubic polymorph is quite easy to explain as it has a fluorite structure (CaF2). Figure 2.2c shows a simple schematic of a tetragonal unit cell. It has a lattice parameter of the order 0.508nm (this however depends on the temperature purity of zirconia that is partially stabilised zirconia at room temperature or pure zirconia at elevated temperature) and a crystal symmetry of Fm3m.   The martensitic transformation For a martensitic transformation to occur, a change in shape is required which must also produce a plane that does not change during transformation. This is so that it is common to the phase produced as well as the parent phase. The phase transformation in zirconia involves a change in volume of between 4 to 5%. The matrix inhibits the transformed particle of zirconia causing a partial shape change. However, the transformation creates a strain which is held in the monoclinic and its surrounding grains. As a result of this, researchers have come up with the idea that transformation stresses are relieved by deformation twinning. When this happens, most of the lattice strain is then restricted to the monoclinic/matrix interface. Micro-cracks can be formed at this matrix/monolithic interface or in the monoclinic particle if this lattice strain increases. The twinning found in monoclinic is caused by deformation twinning, as the researchers have observed using TEM that a section of the st rain related with the transformation happens as a result of a mechanism known as slip. (3) The phase transformation particularly from tetragonal to monoclinic is of great importance, as it attributes the zirconias excellent properties. [from fulltext.pdf] It was firstly discovered by Garvie et al that the transformation of metastable tetragonal phase to monoclinic phase acts as a toughnening mechanism to crack propagation resistance in zirconia. The transformation is quick and results in a 4 to 5 percent increase in volume which leads to formation of micro-cracks and eventually macro-cracks in the material. This process induces compressive stresses and thus toughens the materials. Gupta et al backed this theory up. Studies showed that the transformation mechanism is highly dependent on grain size and by doping the ceramic material with stabilisers. Examples of stabilisers are yttria (Y2O3), magnesia (MgO), calcia (CaO), etc. Y-TZP ceramics is in the family of these toughened materials. Tetragonal zirconia doped with Yttria (Y-TZP) has great strength of over 1000MPa and tou ghness weighing between 6 and 10 MPa.m1/2. This makes it an ideal contender in medical applications, particularly in hip joints. ZrO2 Y2O3 The phase diagram shown in figure 3 was firstly discovered by Scott (1975), this study was agreed and used by many more researchers. The tetragonal phase field is the main aspect of figure 3. It shows that up to about 2.5mol% of Yttria can be produced in solid solution in addition with the low eutectoid temperature leading to the formation of a fully tetragonal ceramic, this will happen as long as the grain is of an appropriate size. The theory of transformation toughening produced some excitement in the materials industry however this excitement came to a halt when Kobayashi et al discovered a flaw in Y-TZP ceramics. Y-TZPs undergoes low temperature degradation during ageing at temperatures ranging from 100 to 4000C, this is particularly enhanced when it is exposed to water or is in humid environments. This degradation is due to the formation of flaws such as micro-cracks and macro-cracks (mentioned earlier) at the surface which gradually goes into the bulk of the material. These flaws are due to the spontaneous transformation from tetragonal phase to monoclinic phase. Material scientists have documented literature regarding the degradation however there have been contradictory views as to the mechanism of this phenomenon. Figure 4 is a graphshowing the low temperature degradation of different types of TZPs. Figure 5 shows ageing temperature against surface monoclinic levels. Some of these researchers focused on the interaction between water (or water vapour) and YTZP, whilst others focused on ways to prevent this from happened. Sato et al came up with a theory where the hydroxyl group from water (H2O) reacts with zirconia from the bonds between zirconia and oxygen (that is Zr-O-Zr bonds) forming Zr-OH bonds at crack tips. This accelerates the rate at which the metastable tetragonal phase transforms to monoclinic at low temperatures. They came up with the conclusion that there is a strain which stabilizes the tetragonal phase, however under certain circumstances it is released and with the combination other pre existing flaws accelerates the transformation. The theory put forward by Yoshimura et al is similar to that of Sato et al in the sense that the Zr-OH bonds are also formed. However, the reaction process which leads to the same outcome is what differentiates the two theories. Their research showed a comparison of the transformed monoclinic phase to the untransformed tetragonal ZrO2. Hydroxyl (OH-) was in the monoclinic ZrO2 whereas there was no trace in the latter. Due to their findings, they came up with the theory that the degradation process occurred in stages: upon exposure to water, Zr-OH bonds are formed as a result of H2O being adsorbed on the YTZP surface. This creates a stress site which builds up as the OH- ions diffuse through the surface and lattice causing the formation of nucleation sites for the phase transformation. This occurs until the stress reaches crack level causing the transformation to occur at the surface leading to the formation of micro and macro cracks all the way through to the bulk. Lange et al [7] witnessed ÃŽÂ ±-Y(OH)3 crystallites of about 20 50 nm in size forming and came up with the idea that the hydroxide formed creates a monoclinic nuclei by removing Yttria from the grains of the tetragonal phase on the surface. As Yttria is being withdrawn, growth of the nuclei continues until a critical size where it will grow spontaneuously, leading to the transformation of tetragonal grains to monoclinic. Micro cracks and macro-cracks begin to occur as the transformed grain gets large enough. This process happens over and over again as the micro and macro-cracks act as a site for water molecules to penetrate into to the grains. This process occurs only if the grains are larger than the critical size. However, if they are smaller, the transformation will be influenced by the diffusion of Yttria on the surface. Other researchers such as Winnubst and Burggraf support this theory, as they found traces of Yttria on surface layer of the YTZP specimen. Their specimen was exposed to temperature of 1770C in a nitrogen environment for over 5hrs and using an auger electron microscope, they found a yttrium rich surface layer. The listed theories were based on YTZPs mechanism during degradation. Whalen et al identified that the reason for this degradation is the spontaneous transformation from tetragonal phase to monoclinic phase at the surface which then eventually spreads to the bulk. They came up with the idea of stabilising the tetragonal phase. This could be done by either of the following two methods: the chemical factor which is increasing the stabiliser content on the surface or the microstructural solution which is reducing the grain size at the surface. The latter was decided upon and this was done by the process of post sintering grinding followed by annealing treatment. 2.45mol% Y2O3/ZrO2 was the material involved in the research. Samples of the material were made using isostatic pressing at pressure of 275MPa and then sintered at a temperature of 15000C for a time period of 2hrs. A 2mm disk was formed of which its two sides had different surfaces treatments, One side being polished and the other being surface grounded. The phase compositions at surfaces were then examined using XRD. The XRD result indicated there was a significant difference in the phase composition of both sides. The ground side showed little transformation change whereas there was 50% increase in monoclinic phase after annealing. This provided evidence that the ground and annealed surface hindered the process of phase transformation from tetragonal to monoclinic at the surface. As a result of this, there were no micro-cracks formed at the surface and hence the expected mechanical properties were achieved. Talk and compare it to mine later (TEM as oppose to XRD, advantages of process) The aim of this project is to provide evidence (if any) of the occurrence of refined grains (recrystallization) in Y-TZP structures as a result of deformation. The ideology used to explain the concept of recrystallization in metals can be used to explain its occurrence in ceramics as this is a new phenomena in the ceramic industry. Grain refinement requires certain conditions in its exposure in polycrystalline ceramics and they are: plastically deforming the material (as a result of applying a stress) and followed by heat treatment. Deformation is basically a change in body shape which occurs as a result of an applied force. Materials may experience either elastic which is impermanent deformation that upon the release of an applied stress is recovered or plastic deformation which is permanent deformation that is non recoverable when a stress is applied. YTZPs recrystallization behaviour can be explained by its ability to plastically deform. The stress and strain behaviour of a material is used to determine the start and the degree of plastic deformation. Figure 6 shows an example of a typical stress and strain curve. Yield tensile strength is the point at which elastic deformation ends and the material begins to plastically deformation. Most polymers and metals undergo elastic followed by plastic deformation but this is not the case for ceramics. They undergo elastic deformation followed by fracture with little or no plastic deformation. YTZP has superplasticity properties and this nature can be used to explain refinement in its microstructure. Plastic deformation is governed by the movement of large numbers of dislocations. Hindering dislocation motion will increase a materials strength. Ceramics are inorganic materials held together by both ionic and covalent bonds. The bonding combination results in hindering the motion of dislocations, hence their high strength but brittle behaviour. Dislocation is an important factor in understanding plastic deformation and so certain elements need to be examined in order to understand the concept. Most materials comprise of an arrangement of atoms referred to as a crystal structure (these can either be single or polycrystalline that is having multiple crystals as the name suggests). This project will focus on polycrystalline zirconia, however understanding single crystals help in explaining the behaviour of polycrystalline materials. All crystal structures have flaws that distort the regular arrangement of the atoms. These flaws can either be point defect (that is they may have vacancies or interstitials), surface, line (dislocations) and volume defects. The activities and effects of all these flaws are interconnected thus the importance in the need to understand them. As the dislocations move, they tend to interact with one another however this interaction is a complex as an amount of dislocations (rephrased from pdf). The collective motion of dislocations leads to gross plastic deformation. http://composite.about.com/library/PR/2001/blmpi1.htm Dislocations can either be screw, edge or a hybrid of both. Edge dislocation: in this dislocation, the line of defect is parallel to the shear stress. The dislocation movement is similar to that of a caterpillar in the sense that the motion is in small amounts at a time. Figure 7shows a typical schematic of the motion of dislocations. A is the extra half plane of atoms. As shear stress is applied, the bond between the upper and lower part of B is broken. The extra atom plane of atom A bonds with the lower part of B converting the lower part to an extra half plane. This motion causes the top half to move with respect to the bottom half. Screw dislocation: this is similar to that of edge in the sense that it also occurs with shear stress however, the defect line is perpendicular to the shear stress as oppose to being parallel. Just like the edge dislocation only a minute fraction of bonds are broken at a given time. Although the motions are different, the overall plastic deformation for both dislocations is the same. The primary mechanism that causes plastic deformation in crystals is called slip. As dislocations move across the crystals, they shear the crystals along their planes of motion. Slip System The degree of ease of motion of dislocations is different with in all crystallographic directions and crystallographic planes of atoms. Normally dislocation motion occurs in a preferred plane and within that plane there are specific directions at also which it occurs. The combination of the plane and direction is referred to as a slip system. The plane at which this motion occurs is referred to as slip plane, and the direction is referred to as slip direction. The slip system depends on the crystal structure of the material. Slip will only occur when the value of applied the shear stress exceeds a certain critical value. The mechanism at which slip occurs is different in single crystals that of polycrystalline materials. Schmid defined the critical shear stress in single crystals as shown in figure 9: Deformation is much more complicated in polycrystalline materials as the crystallography orientations of numerous grains have to be taken into account. This orientation is random and therefore causes the direction of slip to vary from one grain to another. Its complexity extends further more to the grain boundaries which acts as barriers to dislocation motion. Twinning is another mechanism at which plastic deformation can occur. The idea of twinning in plastic deformation is to allow further slip to occur by producing changes in plane orientations. It occurs when a fraction of the crystals adopts an orientation that is correlated to the orientation of the rest of the untwined lattice in an exact proportioned way. Figure 10 shows an illustration of an un-deformed crystal with one undergoing slip and twinning. There is a clear difference between slip and twinning. The crystal orientation in a slip is the same above and below the slip plane whereas in twinning differs across the twin plane. More differences is illustrated in figure 11 Slip Twinning Where it occurs Widely spread planes Every plane of region is involved Occurrence On many multiple slip systems simultaneously On a particular plane for each crystal Time required Milli seconds Micro seconds Size (in terms of inter atomic distance) Multiples Fractions. ANNEALING PROCESS LEADING TO RECOVERY, RECRYSTALLIZATION AND GRAIN GROWTH Annealing is a high temperature process that causes changes in a materials structure, leading to alterations in its properties. When a material is plastically deformed, majority of the energy is dissipated as heat, but a minute fraction is stored in the material as strain energy which is associated with a range of lattice imperfections established as a result of deformation. The deformation process as well as a number of various factors (such as temperature and rate of deformation) determines the amount of energy stored in the material. A reduction in deformation and an increase in intensity of deformation cause a vast increase in the amount of retained energy. The release of stored energy There are two main techniques of releasing the energy retained by a material due to plastic deformation and they are an-isothermal annealing and isothermal annealing. Anisothermal annealing occurs when the material is continuously heated from a lower temperature to that of a higher one (the energy discharged is determined as a function of temperature) whereas, Isothermal annealing occurs when the temperature is constant. The materials microstructure will undergo either or maybe all of these three restoration processes: recovery, recrystallization and grain growth. The extent of plastic deformation can sometimes determine the mechanisms of recovery and recrystallization. These processes require heat treatment to cause rearrangement of grain boundaries and dislocations. Recovery It is the initial stage of annealing that takes place at the low temperature stage of annealing. As a material is plastically deformed, a minute portion of mechanical energy is stored which exists in crystals as stacking faults, point defects (such defects are interstitials and vacancies) and dislocations. When a material is plastically deformed, it is at a thermodynamically unstable state of higher energy. This is converted to lower energy states by the application of annealing leading to a change in microstructure. There are two process involved in recovery: slip annihilating and polygonization. Slip annihilation occurs when dislocations of opposite signs (that is in the case of edge dislocations, the fusion of the positive and the negative edge dislocation or in the case of screw in which the right hand screw merges with the left hand screw) merge together thereby cancelling each other out. Polygonization is the rearrangement of dislocation after annihilation recovery to a lower energy configuration. During recovery, this strain energy built up is relieved to some extent by dislocation motion, due to enhanced atomic diffusion at high temperatures. Recovery leads to physical properties like thermal and electrical conductivities being recovered to their pre worked states. [ggbk] Recrystallization After recovery, grains are not entirely strain free. That is the energy state of the grains is relatively high. New sets of strain free grains having near equal dimensions in all directions with low dislocation densities are formed. This process is known as recrystallization. This mechanism of producing new equaxed grains is driven by the difference in internal energy between the unstrained and strained material. The process of recrystallization can occur after or during deformation. The manner at which recrystallization occurs is of two kinds which vary with materials. Firstly a continuous manner, at which the microstructure gradually evolves into a recrystallized one or a discontinuous manner at which distinct new grains nucleate and grow Recrystallization after deformation is referred to as static whereas the latter is known as dynamic. The extent at which recrystallization occurs is dependent on two factors namely: time and recrystallization temperature. The temperature at which recrystallization is completed in an hour is referred to as recrystallization temperature. It is usually a third to half the materials melting temperature. The rate at which recovery process occurs is inversely proportional to time (that is it reduces with increasing time). Recrystallization has an entirely different kinetic. During the isothermal annealing, recrystallization starts very slowly then builds up gradually up to a certain point where it slows down. This can be shown in figure 13 In some cases it can be as high 0.7th the melting temperature. An illustration of the relationship between recrystallization temperature and percentage cold work is shown in figure 14. It is understood that as the percentage cold work increases, the recrystallization temperature decreases. Other factors affect the rate and occurrence of recrystallization. The annealing temperature is one of a few factors that have an effect on recrystallization. A materials recrystallization temperature reduces annealing time. The stress applied is another factor both recrystallization and temperature, an increase in stress applied means a lower temperature is required to activate the process. Also, the deformation on the material must be enough to allow nucleation and growth. A process known as grain growth occurs in a polycrystalline material after recrystallization provided the annealing temperature is maintained. The restoration mechanism does not require prior deformation or recrystallization and therefore will occur during annealing in their absence in a polycrystalline material. Grain boundary is the driving force for recovery. Stored energy produced as a result of a material being plastically deformed is released during the process of annealing causing a change in microstructure. This energy released is as a result of various mechanisms due to crystal defect interactions: A decrease in crystal defects due to their reactions with each other. Dislocations with opposite signs interacting causing their annihilation and dislocation loop shrinkage. Relocation of dislocations causing the formation of lower energy configurations such as grain boundaries with low angles. The formation of grain boundaries with high angles. These reactions occur during the restoration process of recovery. After this process, the following can occur: Dislocations as well as point defects being absorbed as a result of the migration of high angle grain boundaries. A decrease in the overall grain boundary area. These micro-structural changes occur during the restoration process of recrystallization and recovery. As a result of these micro-structural modifications, an ideal definition of recrystallization is derived: Along with the micro-structural changes, the properties of the specimen also change correspondingly. Thus, deformation and annealing are important processing methods for producing desired properties of the material by controlling its microstructures. Recrystallization mechanism The start of recrystallization is referred to as nucleation and occurs when dislocations are rearranged so as to form low dislocation density sections that have a high angle grain boundary with great mobility and thus is capable of quick movement over the strained region or recovered matrix. Recrystallization has a low driving force and high grain boundary energies; as a result of these characteristics, thermal variations cannot explain regions surrounded by high angle grain boundaries that are free from defects upon annealing. Therefore, the formation of recrystallized grains does not occur during annealing but previously exists in the deformed state. Three methods can be used to describe nucleation and they are: Movement of high angle boundaries that already exist before annealing: this happens when pre existing grain boundaries move into grains that are highly strained as illustrated in figure 16 this process requires a favourable energy balance between an increase in the overall grain boundary surface and a reduction in stored energy as a result of the removal defects triggered by the migration of the boundary. Movement of sub boundaries (that is low angle boundaries): this model is based on the theory of polygonization where stored energy is reduced during annealing as a result of rearrangement and removal of defects. It occurs when sub grain boundaries besiege regions containing low dislocation densities. Upon formation of sub grains, with the help of sub grain boundary movement, they are able to grow at the expense their neighbouring grains. Dislocations are absorbed by migrating sub boundaries and because of this, their mobility, orientation differences and energies are increased until their transformation into high angle boundaries, thus illustrating nucleation. Sub grains coalescence: this occurs when two neighbouring subgrains merge leading to their crystal lattices coinciding. It is regarded as a slow process but when compared to migration of sub grains is favoured for annealing at low temperatures. it is illustrated in figure 17. In this method, stored energy is reduced leading sub boundaries disappearing, sub grains growing and increase in orientation differences between coalescence groups and their neighbouring sub grains. These lead to the formation of high angle boundaries which move at high speeds and cause the process of recrystallization nucleation. It is vital to identify the fact that the total energy balance that takes the disappearance of sub boundaries into account with the increase and orientation difference is favourable (that is it leads to a reduction in total free energy). This mechanism is illustrated in figure 18. The occurrence of these three models is relatively diverse and they will therefore occur under different conditions. The basic requirement for the occurrence of the movement of pre existing grain boundaries that is the existence of differences in large strain between neighbouring grains is well accepted by researchers. However, there is conflict as to when the mechanisms sub grain boundaries migration and the coalescence of sub grains occur. Researchers believed the coalescence of sub grain boundaries are linked with large dispersion of sub grain angles distribution, relatively moderate strain, and reasonably low annealing temperatures. Whereas the mechanism of sub grain migration is linked with high annealing temperatures, strains that are relatively high and large dispersion in the distribution in sub grain size. Growth of recrystallized regions The basic mechanism causing recrystallization and grain growth is the migration of grain boundaries with high angles. However their driving force is what differentiates them from each other. The energy of the high angled grain boundaries is the main driving force for grain growth whether it being abnormal or normal growth. Whereas that for recrystallization is the energy stored during straining appeared as crystalline defects. In defect free regions that are encircled by boundaries with high angle, recrystallization progresses by enlargement of this nucleus over the non recrystallized medium. Grain growth and recrystallizations migrating high angle boundary curvature signal is another important factor that differentiates the two. http://asmcommunity.asminternational.org/portal/site/www/AsmStore/ProductDetails/?vgnextoid=a75a7dcbe4e18110VgnVCM100000701e010aRCRD ASM Handbook Volume 14A, Metalworking: Bulk Forming (ASM International) http://www.accuratus.com/zirc.html http://www.totaljoints.info/ceramic_for_total_hips.htm#2 http://www.azom.com/details.asp?ArticleID=940 http://books.google.co.uk/books?id=eUZw4SgqaPYCpg=PA126lpg=PA126dq=phase+transformation+mechanism+leading+to+microcracks+zirconiasource=blots=fCFhf-satfsig=WNiOjbUtX06mA_d1NkXIEEHcOsshl=enei=r568S9zCKJHFsgaxkd3lCQsa=Xoi=book_resultct=resultresnum=4ved=0CBYQ6AEwAzgK#v=onepageqf=false EXPERIMENTAL PROCEDURE Equipment Three samples of YTZP, 0ne made from 3mol Y2O3/ZrO2 powder and the other two made from the same powder but by two other manufacturers. Focused Ion Beam (FIB): is a technique used by material scientists in the analysis of a materials microstructure. the samples obtained can either be analysed directly using the FIB or transferred and viewed under a TEM or SEM. This process is similar to that of an SEM however ions (particularly gallium ions) rather than electrons. Figures 19a and b show how the FIB operates. The surface of the sample being tested is subjected to primary gallium ion beams. This spits a small part of the material, leading to the formation of either secondary ions (either positive or negative) or neutral atoms on the surface. Secondary electrons (e) are also produced from the gallium beam. This is collected as well as the signal from the split ions to form an image which is either analyzed using the FIB itself, SEM or TEM. http://www.fibics.com/fib/tutorials/introduction-focused-ion-beam-systems/4/ images is from here. GNU image manipulation program (GIMP): is an image editing software used to measure grain sizes. Vickers indentation: is used to form indentations which are viewed and studied under an optical microscope. A square imprint is formed from the Vickers indenter, where the two diagonal lengths are measured. In this project, the Vickers indentation is used to form plastic deformation. The surface defects such as scratches and unevenness need to be controlled, hence the reason for polishing. High temperature furnace: used for sintering and annealing. TEM Cold isostatic pressing Sample preparation Three mol% Y2O3/ZrO2 solid solution powder was used in this experiment. The powder was pressed into a disc at 200MPa, then sintered at 14500C for 2 hours. Two discs were produced, each pressed with loads 7.5 tons and 5 tons respectively. The load was reduced to 5 inorder to reduce the chance of lamination, as it occurred with the 7.5. Measurements and dimensions Sample 1: broken Sample 2 Weight 25.7711g 19.6836g Diameter 39.23 39.11 Height (thickness) 7.1 6.51 Dimensions after sintering<