Food Safety and Hyienic Practices of Street Food Essay

DISCUSSION The street food industry plays an important role in developing countries in meeting the food demands of the urban dwellers. Street foods feed millions of people daily with a wide variety of foods that are relatively cheap and easily accessible (Latham, 1997). However there are significant reports of health problems that have been associated with these street foods(Muleta and Ashenafi (2001); Ashenafi (1995); El-Sherbeeny et al (1985); Abdussalam and Kaferstein, (1993); Mensah et al (2002) and Omemu and Aderoju (2008). Street foods are sources of nutrition for many low-income groups at affordable prices in large urban areas.Nevertheless, there are also several health hazards associated with them. These foods could be main vehicle for transmission of severe and fatal diseases that could be life threatening. Contamination of these foods could result from pre or post cooking contamination from the food handlers. Street food vendors are often unlicensed, untrained in food safety, food hygiene and sanitation, and work under crude unsanitary conditions (FAO 1990). Muinde and Kuria (2005) in their study in Nairobi, Kenya found that over thirty-five percent of the vendors belonged to the age category of 20-25 years. Sixty percent of the vendors were male while 40% were female. Sixty-two percent of the vendors interviewed had primary education and below, 36.3% had secondary education while only 1.3% had college education. In our study we found women made up 66.67% of the vendors while males made up 33.33% who fell into the average age group of 31-40 years with mean age of 41.23 years. This is in contrast with their findings. In Accra the street food trade was conducted by children aged >10 years and by women aged.

“Death on the Ice” by Cassie Brown Essay

Since the beginning of time the individual has been in a conflict. In the novel Death on The Ice by Cassie Brown we are shown how the crew of the Newfoundland survived in great hardship. The examples I will be showing you are of Jesse Collins with his struggle against the failing hope of the men, Cecil Mouland and his determination to live, and also Captain Abe Keans pride against the morals of Saint Johns. Every human being going those adversity through their lifetime, whether it be failing school, trouble with friends or family or even getting to school on time. Throughout the story Jesse Collins was referred to as the â€Å"Indomitable Jesse Collins†. On the first night that the men of the Newfoundland were stuck on the ice the men were tired and hungry from their march from the Newfoundland to the Stephano, all the men wanted to do was to get something to eat and lay down to sleep. Jesse knew that if they stopped moving and slept that they would most likely never get back up again, so instead he motivated the men. He wouldn’t let them sleep or even sit down for any amount of time. Jesse kept the men moving by walking in a circle and patting the back of the fellow in front of them to try to also warm up their shoulders. When the men’s eyelids would become frozen shut by the ice they would stumble around blind until Jesse Collins came to each of them, on by one he would bit off the ice chunks from the eyebrows and eyelids so they could see once again. In turn of him biting off the pieces of ice he froze he lips. Since Jesse was so determined to keep the men on his pan alive, that he lost only a couple of men during the night in contrast to Dawson’s pan which was referred to as a morgue. Cecil Mouland was a seventeen year old at the time of the time of the disaster, it was his first time going onto the ice. Cecil had to walk to Doting Cove with his cousin Ralph Mouland and a few friends. Cecil was determined from the time they realized that they were stuck on the ice that he was going to survive. Cecil stayed close to his Ralph because he said that if Ralph died his cousins parents would blame him. One of the reasons that Ralph lived on the ice was because of Cecil not allowing him to sleep for anymore than a few minutes, and also from Cecil sharing his chewing tobacco with him. The reason that Cecil had chewing tobacco with him was  because his grandfather told him to never let his face freeze or that would be the end of him so he chewed on the tobacco the entire time he was on the ice until the last night where he ran out of it. Cecil was heard saying numerous times that he wasn’t going to die and that he was going to see his girlfriend Jessie once again. When the rescuers came, Cecil was carried on a stretcher back to the ship. When he passed a seal he asked for it to be killed so he could drink its blood and eat its heart, he was quoted as saying it made him feel a little bit more human. Cecil made it back to his sweetheart Jessie, he married her and lived for more than fifty years after the tragedy. Captain Abe Kean was a well respected captain before and after the disaster, and was held with high regard. When the captain testified at the trail about the Newfoundland Disaster he believed every word he said and even went as far to say that he did everything above and beyond his duty. Captain Abe Kean was stuck in the middle of the disaster because the Newfoundland men were being sent to his ship on the first night that they were stuck on the ice. When they reached the Stephano they were told to get a quick bite then to get back over the side onto the ice and head Southwest to a patch of seals. When one of Abe Keans sons sent a message to him to asking about the situation of the Newfoundland crew it was left out of the message that the Stephano received. When the trail first became and the people of Saint Johns wanted to hear Captain Abe Keans side of the story they were able to hear it because he was still out on the ice sending his watches over the side for more pelts so he could be high liner of the season. Throughout the entire thing he never once admitted that he was the cause or at fault for the disaster, the only thing he said that could have been an admission of guilt was that if the Newfoundland crew had taken any longer to get to the Stephano he would of sent them all back to the Newfoundland so then they wouldn’t of been stuck out on the ice. More than these three men had to endure their own challenges during the Newfoundland Disaster, the survivors showed they had the endurance and the will to go on living. The examples that I have shown you from the novel Death On The Ice shows you the peril on the human will that the men had to  endure to survive the night and also to be happy with their conscious.

W2 Disc Innovation Organization Essay Example | Topics and Well Written Essays - 250 words

W2 Disc Innovation Organization - Essay Example Two guidelines that fuel innovation at Nike are: (1) asking questions on the organization’s competencies and its directions by understanding risks and opportunities; and (2) using scenario planning to â€Å"assess the potential impacts that external issues such as climate change or resource scarcity might have on NIKE† (Nike, Inc., 2014, p. 1). These guidelines are consistent with those behaviors which managers should encourage to ensure innovation is applied: (1) ask questions to identify opportunities and problems; (2) learn new skills; (3) assume a proactive stance and take risks; and (4) align personal values and beliefs with the organizational values and goals (White & Bruton, 2011). According to Nidumolu, Pralahad, & Rangaswami (2009), â€Å"the key to progress, particularly in times of economic crisis, is innovation† (p. 1). From the guidelines set by Nike, as well as lessons learned from White & Bruton (2011), innovation could be strategically managed through the knowledge of theoretical frameworks, and effectively applying these in contempory settings, toward attaining explicitly defined goals. Nidumolu, R., Pralahad, C., & Rangaswami, M. (2009, September). Why Sustainability Is Now the Key Driver of Innovation. Retrieved from Harvard Business Review:

Knowledge Management Essay Example | Topics and Well Written Essays - 2500 words

Knowledge Management - Essay Example In order to efficiently control people who comprise the desired tacit knowledge, it is fundamental to take into consideration their cultural and social values, likings and dislikings, feelings and eagerness’s for creating new knowledge (Asian Foundation, 2008). The paper includes the recognition and analysis of knowledge management as a crucial component in organisational progression and also the importance of managing the people who deal with managing knowledge in the organization as well as the effect of wrong culture on reducing the effectiveness of knowledge management. Significance of Knowledge Management in the Organisational Context Knowledge management is one of the most critical arguments in this world of globalization. It is famous both in the industry and the information research world. In reality, an individual deals with huge amount of data and information but these do not become knowledge unless certain value is found out of it. For this reason, knowledge managem ent is required. Knowledge management deals with the processes of acquiring, creating and sharing knowledge and cultural and technical justifications that can substantiate them. Knowledge management is the collection of numerous technologies of information that are used to simplify the gathering, organizing, alteration and transformation of knowledge among employees. Knowledge management has both benefits as well as limitations. The various advantages are focused in a brief way. In every organization, there is need to find the specific knowledge which can be utilized by individual’s for future requirements. This would rather help to gain more knowledge in a short time frame. Besides, the other crucial aspect is the ability of all individual employees to use the organization’s knowledge and... The intention of this study is knowledge management as one of the most critical arguments in this world of globalization. It is famous both in the industry and the information research world. In reality, an individual deals with huge amount of data and information but these do not become knowledge unless certain value is found out of it. For this reason, knowledge management is required. Knowledge management deals with the processes of acquiring, creating and sharing knowledge and cultural and technical justifications that can substantiate them. Knowledge management is the collection of numerous technologies of information that are used to simplify the gathering, organizing, alteration and transformation of knowledge among employees. Knowledge management has both benefits as well as limitations. The various advantages are focused in a brief way. In every organization, there is need to find the specific knowledge which can be utilized by individual’s for future requirements. Th is would rather help to gain more knowledge in a short time frame. Besides, the other crucial aspect is the ability of all individual employees to use the organization’s knowledge and experiences in their own way so that it can be helpful in the path of life. Moreover, another significant point of concern is availability of the knowledge, at exact time and in right manner so that it can be transmitted according to the needs. Thus, knowledge management enables an organisation to gather required information for reference in any point of time by any employee.

Metropolis reivew Essay Example | Topics and Well Written Essays - 1000 words

Metropolis reivew - Essay Example As The Guardian observer said, Metropolis predicted the ideology of the class and race in 20th century (Bradshaw). Metropolis in a very distinct and accurate way combines social criticism, science fiction, psychological narrative and powerful love story. The combination of these factors makes it incredibly interesting to watch and impossible to ignore its huge contribution to the cinema medium and science fiction genre. Fritz Lang’s masterpiece is full of allegories, symbols and metaphors, but nevertheless it tells quite simple story though makes it in a way that makes viewer feel involved. The story tells us about the struggle between two different classes, which are represented by the love-duo of Freder and Maria who met each other by chance. The struggle takes place in the dystopian futuristic city of Metropolis which is ruled by indolent and cruel industrialists, who live in big skyscrapers and oppressed laborers who live underground. As you can see, Mr. Lang puts working class under the ground literally where they work hard so the city can stay alive, no matter what the cost is. Real millionaires of that time would be probably happy to put rebelling working class out of their minds and sight -under the ground. In the era of industrial progress when machines started taking control over the manufacture and human life in general, Metropolis turned out to be especially up-to-date. This industrial circumrotation was portrayed as horrible and fearful Molloh which can obviously be interpreted as Biblical symbol. While in real life hard-working families were hungry and op pressed with their job being taken from them and given to machines, Molloh-machine eats workers like a hungry giant or a savage beast in the movie. As Mr. Roger Ebert said, Metropolis forestalled countless symbolic and futuristic cities of the many films to come (Ebert). The City of Metropolis is a symbol of inequity and oppression because it is built with unhappiness and

From the period of the Spanish American War through the end of World Essay - 1

From the period of the Spanish American War through the end of World War two, why does the United States move from relative isol - Essay Example Isolationism denotes to United States’ longstanding unwillingness to become engaged in European wars and alliance. Isolationists embraced the opinion that United States’ perspective upon the globe was dissimilar from that of the European cultures, and that United States could enhance the root of democracy and freedom by channels other than conflict. United States’ isolationism did not denote is entanglement from the global phase. Isolationists, thereby, were not opposed to the impression that the American should be a global player, and much further its ideological, economic, and territorial interests, predominantly within the West Hemisphere. In the 1920's, the United States is seen marinating its isolation policy all through, but also, its aspects of developing into an internationalist. United States can be equated to a jellyfish where it avoided any external involvement except for trade undertakings, and then later it advanced into a hawk- devotedly pledging fo rces to outdoor wars to gain influence and resources. America remained isolationists via factors like dismissal of the Alliance of Nations, as well as closing accesses on migration, yet occasioned internationalist actions. United States moved from a relative isolation to an internationalist when United States domestic support for Cuba independence entangled the American in a conflict with Spain upon the Cuban’s island. The United States went into war with no strategies other than sinking the Spanish convoy in Manila Anchorage and it undertook months to dispatch troops to Spain with the Spanish putting up hardly any resistance. The US was able to conquer Spain; both countries signed the Paris Treaty. The verdict to assist Cuban opposition was a key retreat from the customary United States’ way of liberal patriotism. The consequences of United States’ global involvement resulted in the Cuban sovereignty under the Paris treaty of 1898. The treaty led to the surrender of Spanish chattels to the American country. These included the Guam Island, Puerto Rico and the Philippines. The American abruptly became a colonial hegemony with international dependencies. The United States colonial ac countability became a permanent undertaking and not just a temporary thing. This is seen when United States made reflective changes within its diplomatic posture. This transformation made the United States immune to the early 19th era foreign policies as the nation had transformed and it also possessed nearly all features of a prodigious power. It stood out from other nations in respect to geographic size, population, two oceans, military capability and economic resources. The negotiation of the Paris treaty and the Cuban war placed new responsibilities and duties in the palms of the United States that it vowed to execute as a ruler of nation-states. United States new way of life was a high decree and promise of civilization. The American global involvement rendered it to engage in close as well as more intricate affiliations with other global great powers. This undertaking rendered the conventional foreign policy old-fashioned. This global involvement of the United States saw it re treat from its customary isolation attitude.[4] The American policy formulators were enforced to cogitate a huger global involvement since they had to formulate new policies Asia. This began with the Monroe Policy amendment. The U.S. President Theodore Roosevelt through the Roosevelt Corollary amended the Monroe doctrine. This change was triggered by the uncertainties that the European creditor countries would utilize the unpaid dues of the Latin American countries to obtain political hegemony over them. ________________________________________________________________________ [4]Rosenberg, Emily S. Spreading the American Dream (New York: Hill and Wang, 1982), 27. The Monroe doctrine amendment gave the United States the right to exercise a universal police power in the emergence of a transgression or impotence act by any nation. The

Unit 4 Discussion Board Essay Example | Topics and Well Written Essays - 500 words - 2

Unit 4 Discussion Board - Essay Example Mount Sinai NYU Health is an example of a healthcare organization – a holding company – that has a multi-corporate entity. The health organization has several subsidiaries or healthcare divisions serving the greater New York City area. The hospital is listed in the book, Jonas and Kovner’s Health Care Delivery in the United States (2002), as a conglomerate with subsidiaries in ambulatory care, hospitals, and employed and affiliated physician groups. Other subsidiary-companies provide traditional home health services for Medicare, Medicaid, private insurance, and self-payers and other services not covered by federal programs. The organization is centralized, as mission, plans, and CEO financial and acquisition powers are reserved as the parent company’s while local units have separate boards with their strategic authority being limited. (Kovner & Jonas 2002, p. 163). The advantages of a multi-corporate structure in the administration of a healthcare organization such as Mount Sinai NYU Health could be seen in two main areas: profitability and quality of service. In terms of profitability, the multi-corporate structure offers an increase in volume, cost savings, and greater leverage in bargaining with managed care organizations. When it comes to the quality of service, a multi-corporate healthcare organization is said to have improved quality of care that results from standardization and specialized expertise. (p. 164) Another important and obvious aspect about multiple-corporate structure is that it allows for greater flexibility in operations because each division or agency within the whole healthcare organization may assume its own separate legal entity. Therefore, as more services are provided or more subsidiaries are added, the other subsidiaries are less likely to be disturbed. There are critics who argue

Human resources ( Essay Example | Topics and Well Written Essays - 500 words - 1

Human resources ( - Essay Example Further, performance management also entails the individual performance of the employees and accountability for individual performance enhances overall excellence in company management (Pulakos 113). One of the greatest challenges for managers is handling relationships with employees and talking about their performance. Since performance management expects excellent performance from employees, it might be difficult for managers to challenge employees whom they have a close relationship with. Sometimes it’s hard to tell off a friend for her performance due to fear of rejection or conflict. When a manager fails to undertake responsibilities of performance management by avoiding the conversation on some members, a question of proper performance management arises (Armstrong 77). There are several factors that lead to failure in performance management in the organization as a result of mistakes made by managers. To begin with some managers overlook the essence of conversation with employees for their poor performance and rather concentrate on the process of improving performance in the organization. The second mistake made by managers includes failure to outline a clear link between the strategy and the execution of the task. Thirdly, managers fail to put a distinction between good performance and poor performance such that no consequences are applied for poor performance. Finally, managers may leave the responsibilities of performance management to HR department thus employees feel uninspired and lose focus on objectives (Sydor 45). The biggest concern involved in performance management involves the skills and competency of handling performance. Many people fail on managing performance because they don’t possess the required skills or they don’t understand what performance management requires. For instance when a person is assigned the role of performance management and has

Reflective Journal Essay Example | Topics and Well Written Essays - 1500 words

Reflective Journal - Essay Example It is our destination and the process of reaching the end of that destination. It is the real meaning of Martin Luther King Jr.’s vision: a sympathetic community where race and social class is surpassed and economic and social justice is the tenet and not the exclusion. It is as well the vision of this empowerment paradigm to social work tradition. The paradigm becomes profound and stretches out to integrate further explanation of how-to and for what reason, enlarged by stronger professional, community, multiethnic, multicultural and global points of view on empowerment mechanism and the commemoration of differences. Countless individuals still desire to live in a society where dearly loved community can be built, where caring bonds of affection and knowing unite us together through our differences. We just cannot give up that yearning. We call for such ties not for the reason that we embrace utopian dreams but because we have wrestled throughout our loves to build this community. The petite circles of affection and care we have been able to shape in our personal lives embody a tangible realistic note that beloved community is not a fantasy, that it previously is present for those of us who have carried out the task of enlightening ourselves for higher consciousness. Ambivalence and indecision indicate the likelihood of resistance. The social work business can be signified as a victorious hegemonic knowledge, yet it cannot attain absolute finality on its manner of perceiving the world: One of the unique features is the pursuit for ties of mutuality and collective identities, through which individuals and their concerns and motives are shaped and which transcend involved exchanges between individualized individuals. This pursuit may have been diminished, yet it has not been totally eliminated. There are other discussions wrestling for articulation from users of services provided by social work: types of

Chinese and American High School Essay Example | Topics and Well Written Essays - 500 words

Chinese and American High School - Essay Example So, a student who is attentive but never speaks up is prone to receiving a lower grade. However, in America, students’ personal expression is valued heavily, which affects the final grade. Many classes are based on group-based discussion, speeches, and classroom participation. The high schools of both the countries express cultural values. The Chinese classroom environment is collectivist where the teacher is the authority and the students lead him, while an American classroom is individualistic where each and every student is given attention. Chinese teachers may call students in front of the class, and tell them to discuss the lesson or ask questions. American students consider it damaging for their self-esteem if they are called individually in front of the class. They consider it shameful if they are not able to answer a question while the whole class looks at them. This is not the case in Chinese classrooms.To conclude, both the Chinese and the American high schools are f it for their own countries’education systems. Both have their own advantages and disadvantages, and their own systems of admissions and examinations. There are differences in classroom environments, parental concerns, teacher attention, and curricula. No matter how much different they are with respect to their classroom environments, teaching processes, and examination systems, the truth is that both countries’ high schools are trying their best to raise highly qualified students who are able to go far ahead in their academic lives.

Monopoly versus perfect markets Essay Example for Free

Monopoly versus perfect markets Essay This paper investigates the two extremes of market structures. A monopoly firm, and a firm which operates in a perfectly competitive market. We will compare features, similarities, differences, advantages and disadvantages. The monopoly firm I have chosen is Thames Water. This company is an accurate example, as it’s the sole supplier of the industry. The firm, is the industry. Thames Water supply water through peoples taps in and around London. Fyffe is my chosen firm in a perfectly competitive market. I think this is a good example. It sells bananas to supermarkets and food suppliers, who resell on to customers. The next two paragraphs explain the features of perfect competition, then a monopoly. â€Å"The theory of perfect competition illustrates an extreme form of capitalism. † (Sloman, 2007:113) There are many suppliers, who all only supply and produce a small fraction of the total output, of the whole industry. None of the firms have any power over the market. (Mankiw, 2001) Barriers to entry do not exist. Therefore firms can enter and leave the market freely. Apart from the money and time it takes to set up the business, there are no other obstacles. Both producers and consumers have perfect knowledge of the market. Therefore they both know prices which should be paid, quality which should be met, availability of the product. Market opportunities for expansion, and entry opportunities in the industry as a whole. The price Fyffe must charge for their bananas will depend upon the demand and supply of the whole market, not just Fyffe personal demand. Hence they have no power over prices. They must follow the market forces. (Sloman, 2007)Established firms in the banana industry have no advantage over firms who have newly entered the market. (Parkin, Powell, Matthews)â€Å"This means they can sell all the products they can produce at the market price, but none at a price which is higher. † (Sloman, 2007:114) If Fyffe raise their selling price above p1, their demand will drop to 0, because if Fyffe raise the price of their bananas, consumers will just buy from another firm selling at the current market price. Illustrated in diagram 2. (Beardshaw, 2001) All firms operating in the banana industry sell a homogenous product, all the firms in the industry sell an identical banana. The theory states there is not a great need for advertising or branding. (McConnell, 2008) I would agree with this statement in the context of bananas. Advertising is not needed as people will not look for a specific brand of banana. They all taste the same. However I think a firm in a market selling shampoos and conditioners would need a certain amount of branding and advertising so people choose their product and gain customer loyalty. In the shampoo industry products are not as homogenous. A pure monopoly owns 100% of the industry. Thames water have a great deal of power, and are price makers, thus they set the price to how much they want to charge. If the consumer cannot, or doesn’t want to pay the price, they have to go without the tap water. In the short run both perfect competition and monopolies can make economic profits, losses and supernormal profits. Only monopolies can manage to sustain super normal profits in the long run. â€Å"Persistant economic profits are called monopoly profits. † (Dobson, 2005:99) Monopolies can sustain supernormal profits and remain safe and unaffected by competition due to barriers to entry. Supply to the industry does not increase with new entrants. (Hunt, 1990). There are many types of barriers to entry. Thames water is known as a natural monopoly, meaning there are barriers to entry due to large economies of scale. (Sloman, 2007) Capital equipment is so expensive and large scale that only one sole supplier could manage to make a profit in the water industry. However Thames Water incurred low marginal costs once they are set up. â€Å"If average cost falls as output increases over the entire range of market demand its a natural monopoly. † (Dobson, 2006:100) â€Å"Each would have a very high average cost at a low output. † (Begg, 2005:134) Correspondingly Thames Water gain barriers to entry through lower costs. This is an artificial barrier. The firm is experienced in their field. Has good knowledge of their market, and will be able to gain the best rates of interest on finance, the best suppliers at the lowest costs, and lean methods of production. Other firms would struggle to compete. If a firm decided to set up and compete with Thames Water, and failed by going out of business there would be huge sunk costs. This occurs when high amounts are spent on capital expenditure, which cannot be used on another business venture. (Sloman, 2007) This is an example of exit costs. It would be a huge loss to the firm, and would discourage firms from entering the market. Thames water also have patents copywrite and licensing. The next two paragraphs explain the effect on demand for perfect competition, then a monopoly. For Fyffe the price charged for the bananas is equal to marginal revenue. Average revenue and demand are also equal to price. If average cost dips below average revenue the firm will earn supernormal profits. If demand is above where marginal costs and marginal revenue meet the firms will be making normal profit. See diagram 2. Normal profits cover opportunity costs of the owners money and time. If Fyffe set output below equilibrium marginal cost would exceed marginal revenue and profit would be lowered. If Fyffe raised output above equilibrium marginal costs would exceed marginal revenue and profits would also be lowered. See graph 1. (Dobson, 2005:99) The demand curve is elastic for the banana industry, but not perfectly elastic. Hence why it slopes downwards in diagram 1. If there is a rise in price for bananas, consumers will spend less on the product, and Fyffe will entail a fall in revenue. In contrast if the price of bananas drop, consumers will buy more of the product, and providing the firm is covering their costs they will receive an increase in revenue, because bananas can be relatively easily substituted by another cheaper fruit. Furthermore bananas will sell for a cheaper price when they are in season, due to a larger supply to the market in this period. Fyffe is perfectly elastic which is why their demand curve is horizontal. See graph 2. The firms prices are not affected by their output and their decisions do not affect the industry. (Ison, 2007) Firms must produce at equilibrium to maximise profits, which is where the market supply, meets the market demand, as illustrated in diagram 1. Short run â€Å"assumes the number of firms in the industry does not increase, as there is not enough time. † (Sloman 2007:114) When a firm produces quantity and price, where marginal costs, and average costs meet they are breaking even. See diagram 2. (Begg, 2005) Consumers are charged a price which is equal to what it costs the firm to produce the extra unit. See diagram 2. If the demand curve for bananas increases short term, the demand curve will shift to the right. See diagram 3. This results in a higher equilibrium and a higher selling price. As selling price has increased farmers will raise their output by increasing their variable costs such as labour and materials. This will result in a larger profit and profits are maximised. As illustrated in diagram 4. In contrast if the demand for bananas was to decrease, this would cause a shift to the left in the demand curve. See diagram 5. This results in a lower equilibrium for the industry, and a fall in the selling price. Consequently all firms in the industry including Fyffe would reduce output, by decreasing variable factors and the firm would suffer economic losses. As illustrated in diagram 6. (Dobson, 2005) If Fyffe or Thames Water are not covering their average total costs in the short run, they should carry on trading, but if they are not covering their short run average variable costs, it would be cheaper to temporarily close down. The theory is known as the short run supply decision. (Ison, 2007) In the long run any firm should close down if it is not covering its total average costs as it is loss making. Called the long run supply decision. (Begg, 2003) When demand increases and selling prices rise in the long term, existing firms are making supernormal profits. Several new firms will enter the market. The supply curve will shift to the right, and supply will increase, which will lower market price. As more new industries join firms reduce their output until they are making a normal profit again. Output of the whole industry will be larger now that more firms are in the market, and there is no incentive for firms to enter, or leave the market as breakeven profits are being made. Referred to as the entry or exit price. When there is a decrease in demand, prices will fall, and firms will reduce output to minimise losses. Eventually due to losses some firms will leave the market which lessens supply and the supply curve will shift to the left. This raises prices due to restricted output, and farmers will start to make normal profits again. So there are less firms and less output in the industry. (Dobson, 2005) In the long run there are no fixed costs in any industry, as firms can change their plant size or machinery. Resulting in a long run supply curve which is flatter than the short run. (Begg, 2003) If all firms operating in the industry restricted supply together increasing demand and prices, new firms would enter the market which would increase supply and lower prices. (Begg, 2005) Thames water are price inelastic, and have a low income elasticity of demand, because there are no close substitutes for their product, and water is a essential item. However they are not perfectly inelastic, as a rise in price will still amount to a small drop in quantity demanded. This means Thames water’s revenue will increase with a rise in price, and decrease with a fall in price. A profit maximising level of output is where marginal revenue is equal to marginal cost but rising up to the demand curve to obtain price. See diagram 9 (Sloman, 2007) The demand curve in diagram 9 represents the value of Thames water to customers, and the marginal curve shows the costs Thames water must pay. The marginal revenue curve must lie below the downward sloping demand curve as marginal revenue is less than price. The further the distance between the demand curve on the right hand side and the marginal revenue on the left the more inelastic the demand, see diagram 9. (Dobson, 2005) ) A firm cannot produce to the right of marginal revenue as this part of the diagram is inelastic. In order for the monopolist to sell a larger amount, the price must be lowered on all previous units, so to prevent this the monopolist may restrict output to keep a larger revenue. Creating scarcity and raising the equilibrium price. (Begg, 2005) â€Å"The excess of price over marginal costs shows the monopolies power† (Dobson, 2005:102) The power to raise prices by selling a smaller amount of output. Diagrams 8, 9, and 10 show long run economic profits, normal profits and losses. Thames water will then check weather the profit maximising level of output covers their total costs in the long run and variable costs in the short run. (Begg, 2003) Thames water is not a contestable market due to the fact it’s a natural monopoly, and has very high barriers to entry. This means they can charge high prices and make supernormal profits, without the threat of competition and new entrants. (Sloman, 2007) Thames water may want to behave ethically when setting prices. If they choose too high a price which people cannot afford this could lead to poverty, but if they charge too low a price this could lead to a wastage of water. Monopolies often use price discrimination when setting prices. Although Thames water do not. Perfect competition cannot use this method. Particular consumers are charged a higher price for an identical service so the monopoly can earn higher profits. (Ison, 2007) Revenue is not lost from previously sold units when price is reduced. More output can be sold ands firms can catch some of their consumer surpluses. See diagram 12. â€Å"Surpluses are the difference between actual price paid and what consumers will have been willing to pay. † â€Å"So the business is treating the demand curve as the marginal revenue curve† (Ison, 2007:138) Only works when consumers cannot buy the product for a cheaper price and sell on to others. (Begg, 2005) A firm operating in perfect competition will achieve allocative efficiency. This exists when price is equal to marginal costs. â€Å" Society is better off when resources are allocated to maximise the total surplus in the market. † (Dobson, 2005:91) Productive efficiency will also be achieved, meaning Fyffe will produce and sell their output for the lowest price they can in the long run giving consumers the best possible value for money. â€Å"Price equals minimum average total cost. † (Dobson, 2005:92) This is good for consumers and society as consumers get the best possible value for money. (Sloman, 2007) Perfectly competitive markets are critised for having a lack of variety, unable to fully satisfy consumers wants and needs. Furthermore the long term entry and exit of firms can be a waste of certain resources such as empty buildings. This is called competitive forces in action. (Dobson, 2005) Monopoly’s are in a position to give us a lower price if they decide to, due to economies of scale. The marginal cost curve is lower than the supply curve in their graph which means the firm can supply more output at a lower production cost. Supernormal profits can fund research and development which will improve the quality of the product. Therefore the monopoly can innovate and introduce new products. (Ison, 2007) However some firms may not do this as they do not need to fight to stay in the industry, with no competition around. (Mankiw, 2001) Joseph Schumpeter said in theory monopolies have more ability and incentive to innovate which can make them better for society. If you imagine a whole industry was taken over by a monopolist, they could eliminate competition and charge very high prices, by reducing output level to which raises price. Supernormal profits represent a redistribution of income from consumer to producer which can be critised on equity grounds† (Ison, 2007:137) Monopoly firms have been known to â€Å"engage in dirty tricks to protect themselves from competition. † They do not produce an output which minimises average costs. Making them productively efficient. â€Å"Perfect competition is rare due to larger companies expanding, gaining economies of scale and market power. Resulting in other firms being forced of the business. So if economies of scale did not exist any industry could have perfect competition. † (Dobson, 2006:94) Monopolies are also rare, and both are extremes of market structures. Most firms lie somewhere between the two. I think the two firms I picked are a fair comparism. They are both from a mixed economy. Thames water will have regulating agencies monitoring them. There are only 3 legal monopolies in Britain Thames Water included. In the past there was a significant amount of monopolies which were government owned. When Margaret Thatcher came into power she privitised these firms as she believed competition would lead to greater efficiency and lower prices which would benefit society as a whole. I agree with her decision and I think after researching, perfect competition appears to be the better option for consumers. Monopolys benefit society in certain situations such as retained profits ploughed back into research and development for medical reasons, and natural monopolies who could not survive in a perfectly competitive industry. Monoplies and perfect competition are becoming more rare as time goes on and who knows what will happen in the future.

History of Slavery in Chesapeake

History of Slavery in Chesapeake The development of slavery in the Chesapeake was due solely to the economic needs of white settlers. Do you agree? History can never adequately provide answers regarding the motives of men and women throughout recorded history; what it can do, however, is to provide a prism through which to gauge the consequences of their actions. With regards to slavery, the consequences of the Southern United States’ intrinsic involvement in the practice of slavery were truly seismic, resulting in the American Civil War and the cementation of the world’s most powerful economic and military force. The role of the Chesapeake in this tumultuous domestic conflict should not be underestimated such was the deep seated nature of the region’s association with slavery. Certainly, economic necessity appears to be at the forefront of this historical fact with the rich tobacco and other grain industries flourishing in the South as a direct result of the burgeoning slave trade. Indeed, as Fogel (2003) underscores, even the slaves themselves could be traded amongst white settlers for economic profit. For the purpose of perspective, the following analysis into the development of slavery in the Chesapeake region must adopt a critical stance attempting to show that economic reasons were indeed the dominant paradigm in the region’s development of a sophisticated slave trade while also underscoring the complex and diverse nature of the early American slave trade. First, however, a conceptualisation of the issue must be attempted. It is important to note that Chesapeake differed markedly from the slave trades operating in the Georgia Low Country after the first arrival of enslaved African workers in the early seventeenth century (transported by Dutch merchants to replace a dwindling European labour force in the North American colonies). Unlike in other English colonies, the Chesapeake was a locale that was only colonised for economic reasons with a sparse colonial population in the days immediately prior to the introduction of slavery. Likewise, the differences within the Chesap eake itself highlight the way in which the values of trade, profit, production and the economy were central to the genesis of slavery in the region, as Philip Morgan (1998:9) details. â€Å"By the late seventeenth century, Virginia had a plantation economy in search of a labour force, whereas South Carolina had a labour force in search of plantation economy.† From the very beginning, therefore, a symbiosis began to form between the determining economic factors of the white settler communities and the introduction of large numbers of slaves into the colonies, with the number of African workers increasing from 13000 to 250000 in the Chesapeake Bay area between 1700 and 1770. The fact that this unprecedented level of African recruitment was accompanied by a drive to attract more female slaves to the colonies so as to increase the plantation population is testimony to the economic imperative at the heart of slave development in the Chesapeake. If slavery were a temporary measure to increase population levels in the area then the imposition of female slaves would not have occurred; only because of the permanence of the economic necessity for slaves did this phenomenon occur. Furthermore, the sheer expanse of the New World landscape required the development of slaves to even begin to cultivate the land for economic production. After the introduction of rice crops in the 1680’s, Boyer (2003:85) estimates that a farmer planting 130 acres of the crop would require at least 65 slaves to do so. With the rapid reduction of the white indentured slaves after the turn of the eighteenth century, the absolute economic need for African slaves in the Chesapeake further increased so that the white plantation owners were utterly dependent on slave manpower in order to function as viable enterprises, competing with highly productive colonies such as the West Indies. Without the slave trade, the Chesapeake region of America particularly the states of Virginia and North Carolina could never have emerged as a major player in the expanding trans‑Atlantic trade system. It was not just for economic reasons that slaves were seen as integral to the rise of the Chesapeake. Health imperatives likewise played a part in the development of slavery during the early years of the colonial era. The African workers were immunised against the malaria that came with the imported rice and grain crops – a disease that rendered white workers obsolete during the formative years of the Chesapeake’s economic development. Moreover, the hot and humid climate of the Chesapeake was wholly alien to the white settlers from the colder European climate while the African workers imported to work on the plantations were much better equipped to cope with the working conditions in the New World, though Oscar and Mary Hadlin (1950:199-222) refute this claiming that it is unjust to blame nature for barbaric human institutions. It is also important to recognise, as Edmund Morgan (2003:314-344) points out, that the slaves were important for sociological and cultural reasons, helping to underpin the rigid class structure that flourished in the southern American states. By taking away the need for a white working class, the slaves of the Chesapeake performed the task of cultural underdogs, which was an integral part of the economic rise of the region as a world exporter. Despite the diverse range of cultural and sociological factors prevalent in the development of slavery in the Chesapeake there is no escaping the pre‑eminence of economic imperatives. Indeed, the manufacturing of the term ‘slave trade’ implies the significance of economic issues in all parts of America that indulged in slavery with the transaction of human beings working in tandem with the production of profits garnered from the rich plantations. As Winthrop Jordan (1976:110-115) details, the underlying prejudice of the white settlers incorporating a profound sense of racial and ethnic superiority facilitated the evolution of slavery as a comprehensive way of life in the Chesapeake. The fact that the Chesapeake was willing to go to war with the Yankees for the perpetuation of the profits generated by the slave trade proves beyond doubt that economic reasons were the catalyst behind the development of slavery in the region. References Boyer, P.S. et al (2003) Enduring Vision: a History of the American People: Fifth Edition New York: Houghton Mifflin Breen, T.H. (Ed.) (1976) Shaping Southern Society: the Colonial Experience Oxford: Oxford University Press Fogel, R.W. (2003) The Slavery Debates, 1952-1990: a Retrospective Baton Rouge: Louisiana State University Press Morgan, E.S. (2003) American Slavery, American Freedom London: W.W. Norton Co. Morgan, P.D. (1998) Slave Counterpoint: Black Culture in the Eighteenth Century Chesapeake and Low Country Chapel Hill, NC: University of North Carolina Press Selected Articles Jordan, W. (1976) Unthinking Decision: Enslavement of Negroes in America to 1700, quoted in, Breen, T.H. (Ed.) Shaping Southern Society: the Colonial Experience Oxford: Oxford University Press Journals Hadlin, M.F. and Hadlin, O. (April 1950) Origins of the Southern Labour System, quoted in, William and Mary Quarterly, Volume 7, Number 2

Population Genetics (Molecular Epidemiology) of Eukaryotes

Population Genetics (Molecular Epidemiology) of Eukaryotes INTRODUCTION The study of the molecular epidemiology of parasitic infections and their vectors is meant to answer the same kinds of questions as those of bacterial or viral infections. As with bacteria, the molecular epidemiology of eukaryotic infections follows the distribution and dynamics of microbial DNA. The key difference, however, is precisely this biology, which defines a distinct approach to molecular epidemiologic investigation of infections caused by eukaryotic organisms. In bacterial reproduction, each individual passes down an identical copy of all the DNA to the next generation. Some eukaryotic pathogens behave reproductively in similar ways to bacteria and reproduce asexually, while others have sexual reproduction for at least part of their life-cycle. The individual is able to generate a clone of itself by binary fission to produce two identical organisms, and if successful, will produce large numbers to the detriment of its host. Asexually reproducing organisms can also exhibit p romiscuous horizontal gene transfer, which can be a major source of variation and adaptation (19), but this is not sex. Sex is the biologically necessary programmed recombination (crossing over) and random shuffling (reassortment) of chromosomal DNA in the process of reproduction. This results in an enormous reservoir of variation. Bacteria in nature are heterogenous conglomerates or communities (13, 19), but when they cause disease, especially in epidemics, it is generally a clone that is responsible and that we track (Chapter 2). Sexual reproduction in some protozoa, many parasitic worms and most vectors, however, never results in a clone with the exception of identical twins. There is genetic conservation, however, within a group of organisms that tends to breed together. In genetics, this is the working definition of a population. For sexually reproducing organisms, the population is the epidemiologic unit to track. Within the group, allele frequencies and thus traits are conser ved under well-defined conditions. The unique power of the genetics of populations is that it reflects not only present individuals but also the populations past and the future potential for subsequent generations (5). Many parasites exhibit both sexual and asexual modes of reproduction, but these life stages are distributed in different hosts. Treatment of their molecular epidemiology is doubly complex, but can be simplified for some questions by considering their biology just in the human host. The whole field of population genetics is perhaps the most complex area of genetics, but it arises from simple precepts. This chapter will outline the basic models used in population genetics and are directly applicable to problems of public health epidemiology. KEY POINTS Asexual reproduction usually produces a clone; sexual reproduction never does. A population is a group of organisms that tends to breed together Allele and genotype frequencies describe populations Allele frequencies and traits tend to be maintained within groups of interbreeding organisms (derived from the Hardy-Weinberg equilibrium) Allele and genotype frequencies can be used to infer population histories Indices and statistics can be used to compare assess population history and to project population dynamics DEFINING GENOTYPE IN EUKARYOTIC ORGANISM   Ã‚   Some terms may not be familiar to some readers, so it is important to define these early. One of the dividing lines between bacteria and sexually reproducing parasites and vectors of human disease is their physical structure and organization. Sexually reproducing organisms will pass some portion of their life cycle where their chromosomes (Figure 5.1) exist as nearly identical pairs (diploid). Some organisms, malaria in particular, also have only one copy (haploid) during their asexual stage, and this is the stage that infects humans. A similar location on each of the chormosomes is a locus, and differences between loci are alleles. The geometry of DNA also strongly differentiates bacteria from eukaryotes (Figure 5.2). Prokaryotes have a single[1], circular chromosome whereas even the simplest eukaryotes, yeast, have at least 16 linear chromosomes. A specific marker on a bacterial chromosome will always be transmitted at reproduction together with any other marker or trait. The same also occurs with an asexually reproducing eukaryote despite having multiple linear chromosomes. A marker on the genome of a sexually reproducing eukaryote, by contrast, will have a 50% chance of being transmitted away from any marker it is not very close to. The labeling of each allele present at the same locus on each chromosome constitutes the genotype. A locus with the same polymorphism at the same site on each of the chromosome is homozygous, and with a different polymorphism is heterozygous. Figure 5.2 OPTIONS FOR MOLECULAR EPIDEMIOLOGY OF EUKARYOTES Study asexual parasites Use a marker close to the trait of interest (if known) Use many markers throughout the genome or sequence Study the whole group of organisms in which the trait is present (population) HARDY-WEINBERG EQUILIBRIUM: THE POPULATION NULL HYPOTHESIS Populations have a mathematical definition based on allele frequencies, which ultimately contributes to the development of tools for key measures of differentiation and diversity. Allele frequencies can differentiate populations, and genotypic frequencies can do so with even greater resolution. The relationship between allelic frequency and genotypic frequency has a simple mathematical relationship which is the definition of a population. If we use the letters A and a to represent different alleles at a single diallelic locus and p and q to represent their respective frequencies, a population with p=0.8 and q=0.2 is clearly different from a population where p=0.2, q=0.8, especially where this kind of result is found at multiple loci. Allele frequencies are not always the most sensitive measure of differentiation. The same allele frequency may still be found in what are clearly distinct populations if assessed for genotypic frequencies. Alleles combine to form genotypes, so the genoty pic frequency is a function of the allelic frequencies. For a diallelic locus where we know the frequency of each allele, the sum of these frequencies is 1 or (p + q = 1). For sexually reproducing organisms the next generation arises from the combination of alleles from a pool of males with alleles from a pool of females. If we imagine that individuals from these pools will pair at random, the subsequent distribution of alleles in genotypes is equivalent to rolling a pair of dice. For independent, random events the probability of 2 events occurring simultaneously is the product of their frequencies [(p + q)female à ¢Ã¢â€š ¬Ã‚ ¢ (p + q)male = 1]. The genotypic frequencies of the offspring for such a population should be p2 + 2pq + q2, if all assumptions are met, where p2 and q2 are the frequencies for the homozygotes and 2pq the heterozygotes. This is the well-known Hardy-Weinberg equilibrium (HWE). This simple quadratic equation is the basis for all population genetics even when it is not measured directly. It represents the expected genotypic frequencies from a given set of allelic frequencies. It is one of the most stable mathematical relationships in nature. It is so much the expectation that when not observed in sequencing projects, it can suggest sequencing errors. It is the null hypothesis and mathematical definition of a stable population. The relationship HWE describes is true under a set of 5-10 assumptions that represent the most important factors that influence population genetic structure. The 5 most common assumptions are that there is: 1) Random mating (panmixia, assortative mating) 2) No selection 3) No migration 4) An infinite population 5) No mutation It is rare to have any of these assumptions met in nature, but the proportions are so resilient that the assumptions have to be severely violated to disturb this relationship, and even so, the proportions will be reestablished within 1-2 generations once the population is stabilized. As with most models, the underlying assumptions are the most important aspects. They are the basis for most conversations in population genetics. MARKERS Microsatellites, single nucleotide polymorphisms (SNPs) and sequencing are currently the genetic elements most employed in population genetics. Microsatellites are short tandem repeats of 2-8 nucleotides (reviewed in [Ellegren, 2004 #128]).  Ãƒâ€šÃ‚   Microsatellites have fallen out of favor in studies of statistical genetics or gene finding, since SNPs and sequencing provide better resolution at the level of individuals. Microsatellites, however, remain important in population genetics since they are mostly neutral for selection and have higher allelic richness and information content. Their rapid mutation rate (10-2 à ¢Ã¢â‚¬ Ã¢â€š ¬ 10-5 per generation) and step-wise mode of mutation can limit their application to questions that extend over short time scales and to certain statistical approaches. SNPs have lower rates of mutation (10-8) in eukaryotes, often are diallelic, are ten times more abundant (10, 22) and have high processivity and scorability. Sequencing essentiall y provides a very dense panel of SNPs and identifies rare variants as well as structural polymorphisms. Mitochondrial and ribosomal DNA markers are much less abundant, less polymorphic and thus less informative than microsatellites or SNPs. Some are under selection and in the case of mitochondrial DNA, the genome is haploid (only 1 copy of chromosomal DNA) and may or may not have sex-specific inheritance depending on the species. They are useful for phylogeny studies, may be more economical to use in laboratories with limited capabilities and are sometimes combined with other markers. MEASURES OF DIFFERENTIATION AND DIVERSITY Areas most often addressed using population genetics are evolution and conservation. These two areas deal with essentially the same phenomenon, but at different time scales, thus the questions, the approaches and the interpretation will differ depending on the nature of the problem. The relevant public health questions in population genetics focus on identity and dynamics of the group rather than individuals over short time scales and directed at the control or extinction of a parasite or vector. Whos sleeping with whom, modes of reproduction, evolution or the last common ancestor are all important in different contexts. They may be useful to help explain anomalies and can influence interpretation, but they are rarely answers to issues of control or intervention. Understanding how diverse a population is or the degree of difference between populations combined with good study design will contribute directly to determining the impact of control measures, host or parasite demographics, resistance, risk and resilience or fragility of the population. The field of population genetics depends heavily on mathematical analyses, some simple and some very sophisticated, to answer these questions. Mathematical treatments of all of the indices and statistics of differentiation and diversity can be easily obtained from textbooks or publications and will not be included here. Fortunately for the mathematically challenged, many open source, individual computer programs are available as well as modules in R. The risk that goes with all readymade programs is a failure to understand what is being asked or the assumptions and limitations of the approach being taken. A list of some frequently used programs is provided at the end of this chapter (Table 5.1). POPULATIN DIFFERENTIATION FST, GST, GST: In addition to the Hardy-Weinberg equilibrium, populations can be further differentiated by other statistical tests.   This is a family of statistics developed as the fixation index (FST) in the 1950s by Sewell Wright and Gustave Malà ©cot to describe the likelihood of homozygosity (fixation in the terminology of the time) at a single diallelic locus based on heterozygosity of a subpopulation compared to the total population. Theoretically, values should range from 1 (no similarity-every individual is genotypically different) to 0 (identity-every individual is genotypically same). Nei (16) extended the FST to handle the case of more than two alleles and developed the GST[LR1]. Although the term FST is often used in the literature, formally most studies today will employ the GST. When highly polymorphic loci, such as microsatellites, are genotyped, the GST severely underestimates differentiation and will not range from 0 1. Hedrick (11) adjusted the range of va lues for the GST by dividing it by its maximum possible value given the markers used. This is the GST. The GST makes possible the full range of differentiation. FST and GST relate to inherent properties of populations and contain evolutionary information lost by the GST transformation. FST-like measures have been and continue to be widely used to describe population structure, and their characteristics and behavior are well-known. There are additional related statistics (e. g. à Ã¢â‚¬  ST (4), AMOVA, RST (20), ÃŽÂ ¸ (25)), that address other aspects of differing genetic models, unequal sample sizes, accounting for haploid genomes, mechanism of mutation and selection. D. [LR2]This is sometimes referred to as Josts D, since there are numerous other Ds related to genetics and statistics. There can be logical inconsistencies for estimating differentiation based directly on heterozygosity. Ratios of pooled subpopulation to total population diversities tend toward zero when the subpopulation diversity is high (12). Josts D is based on the effective allele number (see below). Unlike those based directly on heterozygosity, it has the property of yielding a linear response to changes in allele frequencies and is independent of subpopulation diversity. Unlike FST, GST and similar indices, Josts D does not carry information relevant to the evolutionary processes responsible for the present composition of a subpopulation. It is described by supporters and detractors as purely a measure of differentiation (26). It was never meant to do more. Whitlock provides one of the best comparisons of these 2 approaches: This (Josts) D differs from FST in a fundamental definitional way: FST measures deviations from panmixia[2], while D measures deviations from total differentiation. As a result, their denominators differ, and thus, the two indices can behave quite differently. D indicates the proportion of allelic diversity that lies among populations, while FST is proportional to the variance of allele frequency among populations. D is more related to the genetic distance between populations than to the variance in allele frequencies; it may be preferable to call D a genetic distance measure (26). There has been controversy about the use of these different types of indices. There should not be. They clearly address different questions and resolve different analytic problems. It should be recognized that the GST and Josts D yield fairly similar results when the number of populations is small and the markers have a small number of alleles. The GST and Josts D have given similar results in our own studies using microsatellites (2) and in simulation (26) with GST values slightly higher than those of Josts D. Some authors recommend calculating both GST and Josts D, in part to satisfy everyone and in part to obtain the useful information about population diversity their departure may provide. In relation to public health, most questions about parasites and vectors deal with near term events of DIVERSITY Diversity like differentiation has myriad formulations and interpretations. The simplest expression is mean heterozygosity (H). For microsatellite data this is usually high due to the intrinsically high mutation rate of these markers, and markers with higher variability are usually selected. Allelic richness (Ar) is simply a count of the number of alleles at each locus. Differences in sample size will necessarily result in differences in allele number. This is usually adjusted for by statistical methods such as rarefaction (15) to standardize sample sizes between comparison groups. The effective allele number (Ae) is also a measure of diversity, but is already adjusted for sample size. It represents the number of alleles with equal frequencies that will produce the same heterozygosity as that of the target population. The most informative measure of diversity is the effective population size (Ne), a concept also introduced by Sewell Wright. It is designed to address the essential reason that diversity is important, namely, it reflects the strength of genetic drift. Genetic drift is the effect of random transmission of alleles during reproduction to succeeding generations. When numbers of reproducing individuals are small, the genetic composition of the population of offspring can differ by chance from what is expected given the composition of the parents. If two coins are flipped, it would not be that unusual for both to come up heads. If a thousand coins are flipped, the ratio of heads to tails will always be very near the expected 50:50 ratio. Genetic drift is stronger when populations are small or reduced, and weakens the strength of adaptive selection. Like differentiation, there are several formulations for Ne that can provide different values and are designed to measure different aspects of the population. The breeding Ne is the probability of identity by descent for two alleles chosen at random. It is a retrospective assessment of population diversity. The variance Ne assesses the variance of the offsprings allele frequency, and is thus forward looking. It measures recent population changes that affect its genetic composition. Ne can represent the number of actively breeding individuals in the population or the number of individuals in an ideal population needed to reconstitute the diversity in an actual population. It is almost always less than the census population (Nc). It is a key value in conservation genetics and population genetics in general, since it reflects the history and future potential of a population. Increasing drift (decreasing Ne) tends to neutralize the force of directional selection, permits retention of del eterious mutations and hampers the ability of populations to adapt to stresses (9). Despite its importance, Ne can be difficult to estimate in wild populations due to uncertainties of the demographic, genetic and biological context (17, 24). It can be affected by sample size, overlapping generations, sampling interval, sex ratios, gene flow, age-structure, variation in family size, fluctuating population size or selection. Increasing the numbers of markers is less important than large samples for accurate estimates; as much as 10% of the Ne has been recommended [Palstra, 2008 #84]. Its interpretation can also be uncertain. Estimated Ne has been used as an aid in predicting extinction using the concept of a minimum viable population size. Some have suggested that at an Ne of 50-500 a population will experience extinction in the short- or long-run (7). Others have argued that this might occur at Ne = 5000 (14). While it is clear that lack of diversity has an impact on extinction (21), it is also clear that there cannot be a universally accepted number for the minimum viable population size (6, 23). In any case, theory suggests that there is a number defined by the amount of genetic drift below which populations are likely to go extinct on their own. The range for this number is context-specific and will require multiple species-specific studies under multiple conditions. This kind of analysis might contribute to developing a stopping rule as control measures approach elimination.         Ã‚   [1] Leptospira spp. are an exception with 2 circular chromosomes. [2] The condition where all individuals have an equal opportunity to reproduce with all other individuals [LR1]G? [LR2]Does it stand for something?

Track :: essays research papers

Track My heart beating loudly in my chest is the only sound I can here. The air, whipping past my face, tries to curb my inertia but I just press on harder and harder. As I make my turn to go into the straight-away, the next man in the relay team comes into sight. I push my legs harder and harder, but I cannot make them move any faster. There is only one hundred meters left to go before the instant I have to pass the baton the next runner. As I am speeding down the lane like a jet about to lift off, I see the fans cheering in my peripheral vision but I remain focused on my objective ahead of me. I move closer and closer to the red zone, now counting my steps and pacing off the distance in my mind to the sprinter ahead of me. I ready myself and keep telling myself "be patient, wait" then ....."Go," I yell as he harnesses his adrenaline for a good start. I again have to make another critical, split second decision. When should I give him the baton? There can be no mistakes on the hand off. If I miscalculate my steps, it could be disastrous for the team. As I sprint at his newly energized heels, I yell "Stick!" He reaches his arm back in a robotic- like manner and I slam the baton in his hand, so he will not lose a handle on it. It is a successful hand-off and my body jars, as I try to bring myself to a quick stop. My journey is over but the next runner's has just begun. Track is a big part of my life and it holds much more significance to me than just running. I would not even get the opportunity to set foot on the track if I did not practice several hours a day, running the same stretch of track twenty times over. This may seem like insanity to others but to me it is a way to focus my energy and discipline my mind, as well as my body. Running a race to me is like life; you have to pace yourself and being better than the next guy is a must. Like one who does not receive a promotion in business for not working to their potential, I will not make varsity if I do not strive to be the best I can be, on and off the track. The Baton is my hopes and aspirations and Track :: essays research papers Track My heart beating loudly in my chest is the only sound I can here. The air, whipping past my face, tries to curb my inertia but I just press on harder and harder. As I make my turn to go into the straight-away, the next man in the relay team comes into sight. I push my legs harder and harder, but I cannot make them move any faster. There is only one hundred meters left to go before the instant I have to pass the baton the next runner. As I am speeding down the lane like a jet about to lift off, I see the fans cheering in my peripheral vision but I remain focused on my objective ahead of me. I move closer and closer to the red zone, now counting my steps and pacing off the distance in my mind to the sprinter ahead of me. I ready myself and keep telling myself "be patient, wait" then ....."Go," I yell as he harnesses his adrenaline for a good start. I again have to make another critical, split second decision. When should I give him the baton? There can be no mistakes on the hand off. If I miscalculate my steps, it could be disastrous for the team. As I sprint at his newly energized heels, I yell "Stick!" He reaches his arm back in a robotic- like manner and I slam the baton in his hand, so he will not lose a handle on it. It is a successful hand-off and my body jars, as I try to bring myself to a quick stop. My journey is over but the next runner's has just begun. Track is a big part of my life and it holds much more significance to me than just running. I would not even get the opportunity to set foot on the track if I did not practice several hours a day, running the same stretch of track twenty times over. This may seem like insanity to others but to me it is a way to focus my energy and discipline my mind, as well as my body. Running a race to me is like life; you have to pace yourself and being better than the next guy is a must. Like one who does not receive a promotion in business for not working to their potential, I will not make varsity if I do not strive to be the best I can be, on and off the track. The Baton is my hopes and aspirations and

Information Technology †Wireless local-area Networks (WLAN) :: essays research papers

Information Technology – Wireless local-area Networks (WLAN) In today’s world where organizations need to keep in contact with employees there seem to be more ways than ever to stay connected. This can be a burden for small organizations that do not have a large information technology (IT) staff to keep them updated with the latest technologies (Cisco, 2004). A significant way for employees to stay in touch besides cell phones, laptops and hand held computers is wireless local area networks (WLAN). Also known as LAWN, a wireless local-area network uses high frequency radio waves rather than wires to communicate between computers or other devices (Webopedia, 2004). Business owners are now recognizing the benefits of incorporating wireless network into their organizations. A wireless local area network can be very beneficial because of its mobility and increased employee productivity, but organizations still harbor doubts about its security and reliability. Wireless local area networks (WLAN) provide a variety of benefits to an organization. It can provide mobility and flexibility, which can all lead to improvements in productivity and business opportunities (Wireless LAN, 2004). Wireless local area networks (WLANs) keep mobile workers connected without information technology (IT) professionals having to install wiring through out a building. Temporary workspaces can be set up and internet access can be made available in different meeting locations without the need to rewire. Wireless Internet service providers (WISPs) are also offering access at various locations that would make it convenient to travelers and mobile workers (Public Access, 2004). They are able to connect their laptops or other devices without wires or having to find a data port in airports or hotels. Unlike the past when employees worked from the same location, organizations today enjoy more freedom and flexibility in their workforces because of wireless local area net works (Cisco, 2004). Both organizations and employees enjoy a combination of improved speed, collaboration and accuracy when they invest in a wireless local-area network (Intel, 2004). Wireless local-area networks (WLAN) have given workers the advantage of completing their work away from their office and as a result improve their overall productivity. NOP World through an independent survey discovered that wireless local-area network (WLAN) users stay connected long enough to show an increase in productivity (NOP World, 2003). Different organizations using wireless networks enable their employees to gain access to valuable information pertaining to the business whenever necessary. Not only would vital data be available that could aid an employee in closing a deal, but time could also be saved when correspondences can be answered quickly and at any place via e-mail.

Personal Narrative- Playground Memory :: Personal Narrative

Personal Narrative- Playground Memory Looking back on a childhood filled with events and memories, I find it rather difficult to pick on that leaves me with the fabled â€Å"warm and fuzzy feelings.† As the daughter of an Air Force Major, I had the pleasure of traveling across America in many moving trips. I have visited the monstrous trees of the Sequoia National Forest, stood on the edge of the Grande Canyon and have jumped on the beds at Caesar’s Palace in Lake Tahoe. However, I have discovered that when reflecting on my childhood, it is not the trips that come to mind, instead there are details from everyday doings; a deck of cards, a silver bank or an ice cream flavor. One memory that comes to mind belongs to a day of no particular importance. It was late in the fall in Merced, California on the playground of my old elementary school; an overcast day with the wind blowing strong. I stood on the blacktop, pulling my hoodie over my ears. The wind was causing miniature tornados; we called them â€Å"dirt devils†, to swarm around me. I stood there, watching the leaves kick up and then settle. My friends called me over to the wooden playground surrounded by a sea of mulch chips. The bridge squeaked furiously under our weight. An unannounced game of tag started and we found ourselves weaving in and out of the wooden fortress and the trees that surrounded it. My shoe became untied and I took a time out to tie it with a method that no one uses here. We heard an adult voice; it was time to go in. We lined up single file, supposedly in alphabetical order but no one ever does. I liked that, I never liked being in the back. While waiting for everyone to line up, I looked up at the trees that line the walkway. Despite the time of year, I noticed sparse flowers growing on the trees.

Identification of chosen population Essay

Mexico has replaced United States as the most obese country in the Western Hemisphere. The problem of obesity in Mexico has become a global public health challenge and was accepted by the World Health Organization as such in 1997. 70% of Mexicans are overweight while 32.8% of them are obese. 1 out of every 6 Mexicans adults suffer from weight related chronic diseases such as diabetis, heart disease and certain cancers. 70,000 Mexicans die each year from weight related diabetis. 400, 000 new cases of diabetis arise each year. FACTORS THAT INFLUENCE OBESITY IN THE MEXICAN POPULATION The problem of obesity in Mexico is very complex and it is due to many factors including social, cultural, epidemiological and environmental factors. SOCIAL FACTORS AFFECTING OBESITY IN MEXICANS 1. LOW EDUCATION STATUS There is much lack of knowledge of what nutritious foods are and what the long term effects from eating unhealthy foods are. There is also lack of knowledge about the impact physical exercise can have on health as well as what kind of exercise and how often it should be done. 2. EMPLOYMENT STATUS People who work long hours have no time for shopping for nutritious food and also for cooking at home. Therefore they rely on processed, fried, high fat, high sugar, high calorie foods and high sugary beverages that are easily accessible. 3. POVERTY One of the major social factors influencing obesity in Mexico is poverty. Poverty predicts the place of residence which is usually in unsafe communities. Living in unsafe neighborhoods means children stay indoors not being able to go outside and play. They resort to watching TV and playing computer games. Poverty makes it difficult to buy foods that are healthier, low calorie and more nutritious because it is more expensive. Long hours of work means less time for food preparation at home, shopping for groceries and physical activity. Lack of money and transportation lead to children being unable to participate in sports, recreational activities and youth programs. Poverty also leads to stress which compels people to focus on the immediate concerns rather than risk of long term chronic disease. EPIDEMIOLOGICAL FACTORS AFFECTING OBESITY IN MEXICANS 1. AGE Mexico ranks first in childhood obesity; there are 4.5 million children who are obese. 28% of children between the ages of 5 and 9 are overweight. 38% of teens and preteens between the ages of 10 and 19 are obese or overweight. 2. GENDER Mexican females have a higher obesity rate than males (one third females versus one fourth of males). 3. PHYSICAL ACTIVITY Poor physical activity and an increase in sedentary life-style. 4. LOW SOCIO-ECONOMIC STATUS Mexicans with low socioeconomic status are unable to afford nutritious food, they rely on low cost, processed high-calorie foods and high sugary drinks. LOW EDUCATION LEVEL They lack knowledge about what foods are nutritious and what the long term effects are of consuming high fat, high sugar, highly processed foods and beverages. MIGRATION More Mexicans have moved from rural to urban communities where nutritious food is more expensive, there is less walking or biking due to increased number of cars, there is an increased consumption of coca-cola mainly due to unsafe drinking water. Traditional diets that are healthier are abandoned. Traditional continuous physical labor such as farming, factories, mining were abandoned for desk jobs. CULTURAL FACTORS AFFECTING OBESITY IN MEXICANS Overeating now is conditioned by recurrent or past economic deprivation. Avoiding hunger is part of the culture. Traditional nutritious foods like corn, grains, beans have been abandoned. Foods that could not be afforded in the past and associated with survival are those that now are highly valued like meats, fats, sugars. These foods are also desired because they are associated with a high social status; it is a symbol of integration into society. Acculturation is also a factor; Latinos who take on the values of the white population especially those closer to the United States border, end up eating less fruit, more fried foods. There is also the belief that whatever happens, happens. They believe that if they are going to get diabetis, they get diabetis. It is meant to happen. Also, the parents expect their kids to clean their plate in order to not waste food which ends up in overeating. ENVIRONMENTAL FACTORS AFFECTING OBESITY IN MEXICANS They reside in low income communities where unhealthy food choices are made due to lots of fast food stores. These areas are not safe so they tend to stay indoors and have minimal physical activity. There is limited amount of fresh produce and lots of sweets and snack items. Since these areas are not safe, there are few safe areas where children can play therefore they end up watching a lot of TV with no physical activity. The schools they attend have poor PE facilities so there is not much physical activity in school. There is also a high exposure to commercials of high sugar, high fat snacks. PAST CONSIDERATIONS Obesity rate was much lower in the past as people were doing more manual labor, they were eating more nutritious, home grown grains, beans, corn, fresh vegetables and fruits. The existence of cars was very minimal in the past so people used to bike and walk much more than now. PRESENT CONSIDERATIONS More and more people have moved from rural areas to urban areas. There is an increase in the number of fast food restaurants and a great increase in the daily caloric intake. Due to unsafe drinking water, there is an increase in high calorie sugary drinks. Mothers fill up baby bottles with coca-cola. The life in urban communities is more sedentary. There is a reliance on less nutritious dies that consist of processed foods that are high in saturated fats, sugar and salt content. â€Å"†¦Mexicans spent 29.3% less on fruits and vegetables in 1998 than in 1984, while during the same period, purchases of soft drinks increased by 37.2%† (2006). FUTURE CONSIDERATIONS Obesity leads to increased mortality rates due to diabeits, hypertension, myocardial infarction. Diabetis is the primary killer of Mexicans. The prevalence of diabetis and the cost it incurs has skyrocketed. It is predicted to overwhelm the Mexican health system in the future. By year 2030, the health system is predicted to collapse; 3.24 billion dollars are spent to treat these chronic illnesses associated with obesity. GROUPS IN MEXICO MOSTLY AFFECTED BY OBESITY THE POOR Poor Mexicans are unable to afford nutritious food as it is more expensive. More energy-intense foods such as foods high in sugar and fat are cheap and sought after due to lack of money. Coca-cola is consumed instead of water due to unsafe drinking water. THE YOUNG In the last decade, children obesity rate has tripled. Within the poor classes, the children of the obese parents are malnourished while being programmed to become obese. There is no control in school as to what children eat. Schools are filled with vending machines full of soft drinks and fast food. Their intake of processed, salty, high fat snacks, refined carbohydrates foods is very high while their intake of vegetables and fruits is very low. Their intake of sugary, high calorie beverages such as coca-cola is very high due to its low price, increased availability and lack of safe drinking water. They live in unsafe communities and are unable to play outside and be active. They spend excess time watching TV, play station time and computer. A lot of parents rely on TV for their children due to lack of childcare; this leads to sedentary lifestyle and exposure to unhealthy food commercials. Most public schools lack playgrounds or grounds for exercise. Most public schools, (80%), lack water fountains so they drink sugary drinks. There are few public most parks, swimming pools, play grounds and sidewalks. RECOMMENDATIONS TO IMPROVE 1. FOOD LABELING There is an urgent need for food labeling that is not confusing and misleading. There is a lack of accurate labeling standards and regulations. Portions sizes and contents are unclear and confusing. The labeling has to be formatted in an easy-to-understand by all consumers even by the less well-educated ones. This will address the social factors; the plan will not improve their education level but it will make it easy for them to see if they are purchasing healthy or unhealthy food. This has to be applied to all supermarket shelves, food packaging, restaurants and canteen menus. My recommendation is for the Mexican government to start monitoring these food labeling as it is not reinforced by the government today. 2. MARKETING The heavy consumption of junk foods and sugary drinks can be greatly influenced by the media due to their food related advertisements. 73% of the food commercials are for junk food. There is a need to protect the children from the pervasive effects of the food marketing. This has a powerful effect on their food preference, knowledge on the purchasing habits of children as well as their parents. My recommendation for the Mexican government would be to put in place to mobile phones, Internet, television and in-school promotions. The government should simply ban the advertising of unhealthy food to children and establish a system of monetary fines if certain companies deviate from this. This will address the environmental factors; if children don’t see it they will not buy it. 3. AVAILABILITY Junk food and soft drinks surround children at every step. Vending machines full of high saturated fats, high sugary drinks are all over the school premises and right outside the schools. No nutritious foods are offered to children in schools. My recommendation is that the central and local Mexican Government should place restrictions on the availability of soft drinks and fast food outlets just like alcohol and smoking restrictions. These restrictions should especially apply to outlets near schools. The increased availability of vegetables and fruits should be highly encouraged especially in schools at an affordable price. Elementary and pre-kindergarten schools should ban junk food from being even allowed to be sold in schools. Low calorie snacks and sugar free drinks should be sold only. This plan will take into considerations environmental, social and epidemiological factors. It will not improve their socio- economic status, but at least nutritious food will be more affordable and available even for the poor. If children will not be surrounded by junk food and soft drinks they will not buy it. 4. EDUCATION DUE TO LACK OF KNOWLEDGE The key to this problem in Mexico is to improve their knowledge about nutrition. This can be done through media since the Mexicans including the children spend hours in front of the TV and through schools. The government should direct media into advocating weight loss programs, healthy eating, the importance of physical exercise, and the long term effects of consuming junk food and soft drinks. The schools need to educate and give tools especially to high school students who have more access to fast foods to make better and healthy choices in school as well as after school. They can then bring the message home to the parents who can then make better choices as well. They need to teach the importance of physical activity. Local school districts need to make physical activity and physical education a higher priority or even mandatory. The children need to be taught the importance of drinking water not sugary high-calorie beverages and that they should eat only when they are hungry and not as their culture says avoid hunger. Local grocery stores need to be worked with and asked to move soda, chips, beer and candy away from the entrance to the store and also increase the availability of fresh fruits and vegetables. These recommendations will address the social and cultural factors associated with obesity. This will improve their education level about nutrition therefore helping them make better choices and help them change their belief system that they have to avoid hunger. References Obesity in the Latino Communities, 2006. Retrieved from www/chc.org/research/ Documents/Obesity_in_Latino_Communities.pdf

Socio-Economic and Political Conditions in Sparta and Athens After 800 B.C.E.

Ancient Greece was in a pretty bad shape during the period from 1200 to 800 B. C. E, which is referred as the Dark Age of the Greece. Eventually, after 800 B. C. E, Greeks started expanding their empire from the Mediterranean towards east as far as the Black Sea, and towards west as far as the Atlantic Ocean. At this time, two prominent city- states named Athens and Sparta stood as two pillars in the Greek history. Although these two city -states are geographically close to each other in Greece, they were rivals and shared many differences.However, some of the social conditions were similar in these two city -states. During the Archaic age (800- 500 B. C. E. ), these two city- states progressed tremendously both politically and economically. Even though the Greeks came out of the Dark Age and were expanding with prosperity, they faced new problems with growing population, hunger, and land shortage. Moreover, their lands were not fertile to feed the needs of the growing population, an d there was turmoil everywhere because of the tyranny of the aristocrats.To improve their economical, social, and political conditions, the Athenians and the Spartans created new political systems, introduced important reforms and stood as the role models in the Greek political development. The Spartans responded to the economic crisis by conquering Messene, their rich neighbor, in 715 B. C. E so that they can add the rich region’s resources. Sparta is a city -state in the southern part of Greece which was under the control of aristocracy. In fact, Sparta’s asset was its powerful military, and it is the protector of Greece.Spartans oppressed the Messenian slaves after their revolt against the Spartans. In order to appease the non- nobles, who demanded equal rights, as they assisted the Spartans in the war, the aristocrats later, reformed the state system to â€Å"Lycurgan regimen. † According to this reform, all Spartans were given equal rights, and the state wa s ruled by two kings with the assistance from the nobles. Taking into consideration the economic situations in Sparta, the Messenian slaves called â€Å"Helots† did all the physical work while the men of Sparta devoted their lives for the military.Boys in their young age were forced into military training. Although family life was important to Spartans, their social life was compromised as men spent much of their lives in the military. So they established close relationships with other men in the military. The main aim of the Spartan men was to be trained as the best infantrymen and sacrifice their lives in the battle. Spartan women were good wives who devoted their lives in bearing children and had rights to own property.In the same way, Athenians implemented law of codes, reforms, and adopted democracy with the help of prominent and thoughtful aristocrats and ascended from the economic and political distress and oppression of the aristocrats. In the late sixth century B. C. E, Draco, an aristocrat, published the first law of code which asserts that law belonged to all citizens, Later, Solon, an aristocrat who became â€Å"archon,† a chief magistrate of Polis, reformed the prevailing social conditions by freeing the slaves, recalling exiles, and made enslavement for debt illegal.He thus introduced democratic ideals into their political system in response to the tyranny of the aristocrats and nobles on small farmers and landowners. Although Athens was under the aristocratic rule in the beginning, it later adopted the democratic form of government under the leadership of a prominent aristocrat named Cleisthenes. Undoubtedly, Athenians were the first to introduce democratic sovereign and legislation with a council (â€Å"Boule†) and an assembly of citizens (â€Å"Ecclesia†). They also developed their infrastructure, and â€Å"Acropolis† clearly reveals their love for architecture.Young boys were not forced into military and wer e given opportunity to excel in education, arts, and other talents. The Athenians enjoyed better social life than the Spartans, and family life was important. Like Spartan men, Athenian men maintained close relationships with other men. Women were confined to giving birth and raising children along with other household chores, and they were considered inferior to men. Unlike the Spartan women, they had less freedom. Even though Athenians adopted democracy, women and slaves have limited rights and were not granted citizenship. Ancient Greeks rose from their dark age in 800 B. C. E.  and started expanding their empire in the neighboring regions.With their progress several economic and social tensions appeared such as population growth, hunger, and food shortage. In response to this economic and social distress, the two city-states, Athens and Sparta, with their own distinctive social structure, developed into two significant political systems. Athenians emphasized not only on firm p olitical development, education, and culture but also on individual freedom and justice. Democracy and legislation with two presiding bodies were introduced into their political system and even the poor were allowed to vote in the election.On the contrary, Spartans focused on training their youth as soldiers and thus strengthened their military. With the military power they conquered their resourceful neighboring region, Messene, and later reformed their state system with two ruling kings and five noble overseers. Their reform system also presented equal rights to all Spartans. The above discussed political and social reforms were necessary for both the city-states at that time of chaos in order to survive. Even though they underwent many deadly conflicts, Athens and Sparta established themselves as prominent city-states in the political development of ancient Greek history. Socio-Economic and Political Conditions in Sparta and Athens After 800 B.C.E. Ancient Greece was in a pretty bad shape during the period from 1200 to 800 B. C. E, which is referred as the Dark Age of the Greece. Eventually, after 800 B. C. E, Greeks started expanding their empire from the Mediterranean towards east as far as the Black Sea, and towards west as far as the Atlantic Ocean. At this time, two prominent city- states named Athens and Sparta stood as two pillars in the Greek history. Although these two city -states are geographically close to each other in Greece, they were rivals and shared many differences.However, some of the social conditions were similar in these two city -states. During the Archaic age (800- 500 B. C. E. ), these two city- states progressed tremendously both politically and economically. Even though the Greeks came out of the Dark Age and were expanding with prosperity, they faced new problems with growing population, hunger, and land shortage. Moreover, their lands were not fertile to feed the needs of the growing population, an d there was turmoil everywhere because of the tyranny of the aristocrats.To improve their economical, social, and political conditions, the Athenians and the Spartans created new political systems, introduced important reforms and stood as the role models in the Greek political development. The Spartans responded to the economic crisis by conquering Messene, their rich neighbor, in 715 B. C. E so that they can add the rich region’s resources. Sparta is a city -state in the southern part of Greece which was under the control of aristocracy. In fact, Sparta’s asset was its powerful military, and it is the protector of Greece.Spartans oppressed the Messenian slaves after their revolt against the Spartans. In order to appease the non- nobles, who demanded equal rights, as they assisted the Spartans in the war, the aristocrats later, reformed the state system to â€Å"Lycurgan regimen. † According to this reform, all Spartans were given equal rights, and the state wa s ruled by two kings with the assistance from the nobles. Taking into consideration the economic situations in Sparta, the Messenian slaves called â€Å"Helots† did all the physical work while the men of Sparta devoted their lives for the military.Boys in their young age were forced into military training. Although family life was important to Spartans, their social life was compromised as men spent much of their lives in the military. So they established close relationships with other men in the military. The main aim of the Spartan men was to be trained as the best infantrymen and sacrifice their lives in the battle. Spartan women were good wives who devoted their lives in bearing children and had rights to own property.In the same way, Athenians implemented law of codes, reforms, and adopted democracy with the help of prominent and thoughtful aristocrats and ascended from the economic and political distress and oppression of the aristocrats. In the late sixth century B. C. E, Draco, an aristocrat, published the first law of code which asserts that law belonged to all citizens, Later, Solon, an aristocrat who became â€Å"archon,† a chief magistrate of Polis, reformed the prevailing social conditions by freeing the slaves, recalling exiles, and made enslavement for debt illegal.He thus introduced democratic ideals into their political system in response to the tyranny of the aristocrats and nobles on small farmers and landowners. Although Athens was under the aristocratic rule in the beginning, it later adopted the democratic form of government under the leadership of a prominent aristocrat named Cleisthenes. Undoubtedly, Athenians were the first to introduce democratic sovereign and legislation with a council (â€Å"Boule†) and an assembly of citizens (â€Å"Ecclesia†). They also developed their infrastructure, and â€Å"Acropolis† clearly reveals their love for architecture.Young boys were not forced into military and wer e given opportunity to excel in education, arts, and other talents. The Athenians enjoyed better social life than the Spartans, and family life was important. Like Spartan men, Athenian men maintained close relationships with other men. Women were confined to giving birth and raising children along with other household chores, and they were considered inferior to men. Unlike the Spartan women, they had less freedom. Even though Athenians adopted democracy, women and slaves have limited rights and were not granted citizenship.Ancient Greeks rose from their dark age in 800 B. C. E.  and started expanding their empire in the neighboring regions. With their progress several economic and social tensions appeared such as population growth, hunger, and food shortage. In response to this economic and social distress, the two city-states, Athens and Sparta, with their own distinctive social structure, developed into two significant political systems. Athenians emphasized not only on firm p olitical development, education, and culture but also on individual freedom and justice. Democracy and legislation with two presiding bodies were introduced into their political system and even the poor were allowed to vote in the election.On the contrary, Spartans focused on training their youth as soldiers and thus strengthened their military. With the military power they conquered their resourceful neighboring region, Messene, and later reformed their state system with two ruling kings and five noble overseers. Their reform system also presented equal rights to all Spartans. The above discussed political and social reforms were necessary for both the city-states at that time of chaos in order to survive. Even though they underwent many deadly conflicts, Athens and Sparta established themselves as prominent city-states in the political development of ancient Greek history.