Discuss mild cognitive impairment. Including the pathophysiology, Research Paper

Discuss mild cognitive impairment. Including the pathophysiology, symptoms, and prevelance - Research Paper Example The victims develop thinking problems are do not correspond to their age, but the symptoms are less severe compared to those of Alzheimer’s disease (AD). When an individual has MCI, the memory problem may be minimal to mild and at times may be rarely recognizable. In contrast to AD, which causes a gradual decline in cognitive abilities, in MCI memory insufficiency many remain stable for quite long. In some cases, such confirmation of memory loss by a relative, the MCI may progress and transform into AD (Gauthier & Rosa-Neto, 2011) In Mild Cognitive Impairment, the cognitive abilities are more than expected age-related changes but remain functional. As a result, MCI components may be amnestic and non-amnestic forms. MCI’s pathophysiology is multifactorial where amnestic MCI form roots from pathologic variations in AD that are not yet severe to cause dementia. Non-amnestic MCI relates to the cerebrovascular complication, front temporal dementia or no particular pathology. The diagnosis majorly acknowledges the fact that the victim can carry out all their regular activities successfully, without any additional assistance other than they previously required. First, the individual may complain of the typical problem in remembering the identity of people they recently met or trouble recognizing the immediate conversation flow. Additionally, the individual may experience increased tendency to misplace items or associated difficulties. In many scenarios, the individual will be well conversant with those problems and will counteract by always relying on notes and reminders (Gauthier & Rosa-Neto, 2011). The problems are less severe in comparison to the neurophysiological findings that relates to Alzheimer’s disease. In some instances, the victims may have mild problems in carrying out daily activities such as hobbies and another regular thing they did in the past. The old age individuals are more likely to experience MCI that is if they do have a direct

Zip Car Case Study Example | Topics and Well Written Essays - 750 words

Zip Car - Case Study Example The business had a market of people that would enjoy using Zip car. The market was good for those who were able to use the internet and did not have a car available for use at all times. The market for Zip car would target those who did not do a lot of driving throughout the year. It was important for Chase to allow operating costs to be cheaper than the cost of leasing, renting or purchasing a car. By doing this, Chase would entice the targeted market to use Zip cars as a main means of transportation. Funding is a problem for many businesses. Chase, with the help of Danielson, created business plans and presentations that are appropriate for investors. Investors want to see that they are going to receive the money they lent and more. Chase performed the necessary research and gave the investors exactly what they wanted. Seeking a new engineer to create the software was a way to keep cost down and achieve the necessary technology that Zip car needed. A new software engineer costs less than an engineer that has more experience. Little cost cutting techniques like this used by Chase were important for allowing funding to go as far as possible. Zip car had everything lined up to get the business started and seemed as if it could be successful. Question # 2) What is the business model, and how has it changed between Dec. 1999 and May 2000? What do the data from actual operations in September say about how the business model is working? Does this give you comfort or concern? Answer # 2) A business model is important for every business. Business models show the most important part of a business. That part is the businesses numbers. The numbers show everything. If the proper research has been performed and the numbers do not show a potential profit, there is no need to start the business. The business model for Zip car shows the expenses and profit for the company. The business model shows expenses such as leases, insurance, parking

Female Education And A Nations Development Education Essay

Female Education And A Nations Development Education Essay Female education is essential for the development of a nation. This is mainly because women are involved in all sorts of activities both at a regional level and at the community level such as child bearing and household chores etc. Hence it is very important to provide quality education to women to help them contribute to the development of the nation in a meaningful way. Various studies show that womens education is very important in order to improve the socio-economic position of their families. It is the inequality in access to education for female students that prevents them from obtaining the essential education necessary for their well being and their familys development. The traditional thinking of many societies that women are just supposed to do the household work has contributed largely to the low levels of female education around the globe. It is seen however that the societies that have focused on providing better education to women have better indicators of social welfar e. These societies for example have lower infant mortality rate apart from that the issue of lower fertility rates, also increased life expectancy, improved nutrition and most importantly better opportunities for their children. Other factors such as residential status and parents concern and attitude towards female students also plays an important role in improving the educational status of female students in any society. Parents level of education also has a direct impact on their daughters education. The link between the mother and daughter is the strongest. Poverty, parents professional status, lack of skilled teachers and lack of incentives such as scholarships for women, deprivation of parental care and proper educational policies affect the standard of female education. (I.A. Adetunde, 2008) Thus Womens education is a very important issue. Women who are educated can make profound choices in the matter of health, nutrition and basic upbringing of a child. There is great impact on infant mortality health, fertility, productivity and a childs academic performance if women are educated. On 8th March 2004 Laura Bush (the first lady at that time) said on the womens day that when a women is denied education youve denied half of the population the chance to succeed and the chance to contribute to a society and to a culture. she also said that Women are more likely to be able to make informed choice so that their children dont suffer from malnutrition or other diseases and ensure that their children can receive best health care. In Every culture, the responsibility of the upbringing and nourishing of a child lies in the hands of the mother. Due to this responsibility the womens education has gained quite an importance globally. Studies reveal that womens education has strong implications on every aspect of a childs upbringing and one of them is the childs academic performance. Children of educated mothers are seen to have better academic performance as compared to children of less or uneducated mothers. (Tahir Andrabi, Jishnu Das, Asim Ijaz Khwaja: March 2009) Educated mothers can help their children throughout their life, but most importantly they can help their children in their early days of education. They try to indulge their children in more productive educational activities apart from what they study at school. This enhances the childs educational capabilities and helps them achieve success. According to a study an additional year of post compulsory schooling of a mother has a positive impact on their childs academic performance i.e. mothers who stay in full time education beyond the minimum school leaving age are more likely to demonstrate positive educational attitudes and behaviours such as reading to their children. (Leon Feinstein and Ricardo Sabates: January 2008) Higher education is consistently associated with a higher likelihood of marriage, whereas less education is associated with a higher likelihood of divorce (Jennifer March Augustine, 2010). Thus educated mothers tend to have more stable relationships and family status. This in turn affects their childrens academic performance. Children have a healthy environment to live in and thus can concentrate more on their studies and perform well. The flow of resources such as time, money and socio-emotional support etc from the mother to children is affected by this relationship status. (Jennifer March Augustine, 2010). Marital and fertility patterns have been seen to change over the last few decades. Women who are more educated (college graduates) have been the least likely to get married and have children historically. Today however, the situation is changing and this marriage gap is eroding The returns to marriage have changed. College educated women marry later, do not view marriage as a financial security, have fewer children and declining divorce rates since 1970s as compared to women without college degrees. These factors help women to have a better and a healthier family life which in turn helps them in their Childs upbringing. The children of more educated women thus can focus more on their studies as they have a healthier environment to study in and so they perform well (Adam Isen Feb. 2010). A Mothers education influences a child mostly during the childs early years of education (primary education). Educated mothers make their children spend more time in outdoor activities, reading etc and are concerned about their childs progress at school and have expectations of the childs future educational achievements .This encourages the child to focus more on his studies and enhances his capabilities. (Leon Feinstein and Ricardo Sabates: January 2008). Moreover there are substantial intergenerational returns to education. An additional year of a mothers schooling makes a positive contribution to the Childs academic performance. It increases the Childs performance on a standardized math test by almost 0.1 of a standard deviation and reduces the incidence of behavioural problems especially for children aged 7-8.There are various channels that transmit the effect of maternal education to the child, including parental investments throughout different stages of a Childs life and family environment. Educated women tend to have a healthier home environment with better and more stable family lives which then contribute to their Childs educational excellence. Maternal education also reduces grade repetition and the incidence of behavioural problems. Educated mothers basically avoid early childbearing, are more likely to be married to educated men and tend to have higher incomes. Thus they can contribute in several ways to their Childs educa tion for example through books, involving them in extracurricular activities or buying them a computer. This additional investment pays off in the form of improved child performance in all academic aspects of his life. Even if educated mothers work more they do not neglect their children as they are aware of the negative consequences of doing so (Pedro Carneiro, Sep 2007). Also educated mothers tend to spend more time with their children and their children tend to spend more time studying outside school thus there is a strong impact of maternal education on their childs test scores.( Tahir Andrabi, Jishnu Das and Asim Ijaz Khwaja, March 2009). Educated mothers bring in more encouragement and ability for their children to succeed in life. Children of educated mothers are usually more confident, free from anxieties, ambitious, self reliant and more focused. It is seen that an increase in mothers education leads to an increase in the students achievement at school .Those mothers who stayed on in education rather than just having the basic primary education can help their children in a better way. A direct relationship is seen between a mothers education level and their childs academic performance. (Azra Parveen Muhammad Tayyab Alam 2008). Traditionally it has been thought that an increase in investment in womens schooling pays off in the form of increased schooling of the next generation. Some authors have a different view however. According to them the positive relationship between mother-child schooling can not entirely be considered true as it is somewhat biased upward due to the correlations between schooling and assortative mating and heritable ability. The other studies, they argue have not considered these factors and thus conclude showing a positive relationship between mother-child schooling and education. An increase in the schooling of women does not have beneficial effects in terms of the schooling of children (Jere R. Behrman and Mark R. Rosenzweig, 2002). Increases maternal schooling and education instead makes the mothers concentrate less on their homes, family and specifically their children. It is emphasized that the time of the women is an essential factor in childbearing and thus women should concen trate more on their families and not on education. This, they argue will lead to a better academic future for their child. Better schooling of the mother however can improve a Childs health in certain situations. Basically the result of investing in womens schooling requires attention to the role played by schooling in the labor and marriage market for women. (Jere R. Behrman and Mark R. Rosenzweig, 2002) Literacy status of mothers also strongly affects the health and nutritional state of their children thus literate mothers can take better care of their childs health and protect them against several diseases. With illiterate mothers however there are chances of children developing malnutrition especially children less than three years of age who are underweight. Malnutrition negatively affects the childs academic performance. An educated mother takes better care of their Childs health and thus their child is more successful throughout his life. Although there is a positive correlation between a mothers education and their Childs health some studies reveal that there is hardly any significant effect of a mothers education on Childs health if mothers have got only primary education. Further it has been found that the first three years of mothers education has no impact on the Childs health. The impact is seen after the first three years and the result is not linear in education. After 4 to 6 years of education, the magnitude of this effect becomes small but then again picks up after 1 years of education. (Meherun Ahmed May 2009). Nonetheless, some scholars do not completely support the correlation that there is a strong causal relationship between maternal education and child health. According to them this link has hardly been analyzed properly using the most appropriate statistical models. They are using the community-level fixed-effects models and thus argue maternal education may be a proxy for the socioeconomic status of the household as well as for characteristics of the community of residence. Therefore according to them there is a possibility that the positive relationship between maternal education and child health may be untrue. By controlling for a few socioeconomic variables the maternal education/child health link is seen to be weak. Three markers of child health namely infant mortality, immunization status and childrens height-for-age have been examined. Maternal education has a significant impact on height-for-age and infant mortality in only a few countries around the world. However on the othe r hand maternal education has a strong positive effect on childrens immunization status in about half of the countries of the world even after implementing the community and individual level controls. (SONALDE DESAI AND SOUMYA ALVA, 1998) According to another study, educated parents tend to have educated children. The author focused on studying whether the intergenerational transmission of human capital is more behavioural (nurture) or innate (nature). The data collected helped in separating genetic from environmental parental influences. Results of the analysis emphasised that the nurture component is more important for both parents (mother and father).The education of the most educated female adult in a household has a strong positive effect on the schooling of the children in that household. This holds true for a Childs biological parents and for the parents of an adopted child. It can be said that the more the mother is educated, the better the Childs academic performance. When boys and girls are analysed separately it is seen that if the nurture component is isolated, the fathers education matters more for boys whereas a mothers education matters more for girls. The positive effects of the education of the adopti ve parents are only seen for children related to the head of their new households (Damien de Walque, 2005). Research Project Literature Review By Asna Shahid Section G 07U0469 Submitted to Anam Tahir Lahore School of Economics

Iago’s Scheming in Shakespeares Othello Essay -- Othello essays

Iago’s Scheming in Othello  Ã‚   Iago is a powerful predator who exploits those around him by infecting their perceptions of truth with carefully chosen fallacy. His skill in finding the proverbial chinks in others' armor allows him to skillfully weave his machinations of destroying Othello into their minds and actions; by manipulating character's perceptions of Desdemona, Iago gains the leverage he needs to exploit each character. No one is impervious to Iago's seething purpose; even Othello falls prey to Iago's suggestions and insinuations about Desdemona. Iago's constant presence as the stager, as well as his ceaseless - but subtle - reinforcement of events through narration, allows him to be the pivotal force that directs Shakespeare's Othello. In the opening scene, Iago provokes Brabantio against Othello by means of his pawn, Roderigo, and constantly stages the scene, ensuring that everything goes according to his plan. Iago realizes that Brabantio is very susceptible to attacks on his daughter; Iago uses Roderigo as a dummy, through whom he makes such antagonizing claims: "An old black ram / is tupping your white ewe" and "your daughter and the Moor are now / making the beast with two backs" (1.1.90, 121). By inflaming Brabantio's protective nature as a father, Iago directs Brabantio's wrath towards Othello while using Roderigo as a front. Iago successfully bends an unwitting Brabantio to the common goal of destroying Othello. The climax of Iago's power occurs during Iago's successful attempts to convince Othello - against the poor Moor's better judgment - that Desdemona fails to be loyal and that Othello differs too greatly from his fellow citizens to be a part of the Venetianworld. Iago craftily inflames Othel... ... that Iago felt compelled to engineer to perfection and totality; and once Iago's plan falls short of his mark, his pawns grow out of his control and finally expose his dark scheming. Fragility permeates Iago's liminal existence and, as shown, he has to be omnipresent in order to execute and oversee every aspect of his plan. His ambition leads to his downfall; modest desires for revenge blossom into extravagant and uncontrollable machinations which necessitate the deaths of all those involved. Iago finds it impossible to manipulate everyone at every moment, and for this sole reason, fails to bring his plan into full fruition. Work Cited William Shakespeare, The Tragedy of Othello, The Moor of Venice (from Literature: An Introduction to Fiction, Poetry, and Drama, sixth edition. Ed. X.J. Kennedy and Dana Gioia. New York: Harper Collins, 1995.      

Critically Assess Whether Strategic Hrm Leads to ‘High Performance’’

Essay Question 1: ‘Critically assess whether strategic HRM leads to ‘high performance’’ Introduction There is a controversy whether the Strategic Human Resources Management (SHRM) leads to ‘high performance’. A general idea of SHRM is that â€Å"the linkage of management and deployment of the individual within the firm to the business overall and its environment whereas HRM is the activities that take place under this area. † Truss and Gratton (1994). It spotlights on long-term strategy.Two theoretical perspectives to the Strategic Human Resources Management (SHRM) will be introduced and compared to determine whether they manage to ‘high performance’ or not. First, the Universalist approach is ‘one best way’ of dealing human resource to improve business performance. Second, the Contingency approach is to align HR policies and practices with the details of business strategy to create a positive impact on business. In addition, two examples: a large company and a medium-size company will be used to illustrate both approaches practically.At the same time, there are issues associate with theoretical perspectives that need to be discussed. Such issues are the implementation problems as well as the measurement problems. After all, the question will be answered with analysing all of the above. The advantages and disadvantages of each approach will be identified by gathering views of researchers. To the final stage, both approaches are being recognised if the linkage is existence to ‘high performance’ and to the level of measure that are being noticed. Different approaches to SHRM * Universalist approachA Universalist approach is known as ‘best practice’ human resource management (HRM). This approach describes there is ‘one best way’ to manage people in order to improve organizational performance. It argues that all organizations, regardless of sector, size or country, will benefit from identifying, gaining commitment to and implementing a set of best HRM practices. The job of a researcher is to identify what the practices are, and a job of HR professional to implement them. For example, a research from Delery and Doty (1996) identify certain practices that improve organizational performance.The detailed components are ‘high performance work systems (HPWS)’ Berg (1999); Appelbaum et al (2000), ‘high commitment management’ Walton (1985); Guest (2001a, 2001b) and ‘high involvement management’ Wood (1999a). Another researcher by Jeffrey Pfeffer (1998) identifies that seven universally applicable practices will benefit all firms. The components include: 1) Employment security, 2) Careful hiring, 3) Self-managed teams and decentralized decision-making, 4) Comparatively high compensation, 5) Extensive training, 6) Low status distinctions and barriers, 7) Extensive sharing of financial and performance info rmation.The implication is that when a coherent bundle of HR practices is outlined, the integrated HR practices will impact positively on organizational performance. The ‘best practice’ HRM sees there is ‘one best way’ of managing people and that is appropriate across all circumstances. * Contingency Approach On the other hand, the Contingency approach is known as ‘best-fit’ HRM. It takes account of factors such as organizational size, location, sector, strategy and the nature of work. Baird and Meshoulam’s (1998) model advocates that HRM approaches will differ giving to different life-cycle stages.These life cycle stages ranges from start-up to maturity. While an organization is growing and maturing over time, it becomes gradually complex. Therefore, more sophisticated HR structures and policies are needed. This approach focuses on two types of ‘fit’ and ‘line management integration’. The first type is ‘E xternal fit’ and it is commonly known as ‘vertical fit’. It is in coherence and alignment with business strategy and external market factors. When HR policies and practices are aligned to strategic focus, performance will improve.Porter’s (1985) strategic options on 1) Cost Leadership, 2) Differentiation and Innovation and 3) Focus are adopted. The second type is ‘Internal fit’ and it can also interpret to ‘horizontal fit’. HR policies and practices are all fit together so that they are in coherence. They are also mutually reinforcing and are applied continuously. Jeffrey Pfeffer’s (1998) seven practices are adopted. Lastly, ‘Line management integration’ is when line managers act as a critical character in implementing HRM strategy. Best-fit’ HRM suggests that the best to manage people will vary depending on organizational circumstances, and hence, the link to business strategy is key. Empirical evidence of SHRM model * A large company – Tarmac The UK quarrying company Tarmac has over 12500 employees at present. The operations function is key to overall company’s performance. It needs the support of finance managers, zone managers and HR managers. A finance manager delivers financial and management accounts to contribute the strategic decision-making process by forecasting financial performance.A zone manager manages operational performance. They meet and improve targets for cost, quality, delivery, safety and business ethics shown in key performance indicators (KPIs). Lastly a HR manager ensures business managers apply HR policies and procedures. The company’s goal is to achieve objectives by motivating all individuals working together as one team across the business units and functions. Each objective has its strategies. The followings practices are to achieve ‘Engage employees’ and ‘Act Responsibly’ objectives.Firstly, Tarmac focuse s on a high level of employee involvement and encourages high employee commitment to the organization so that workers feel they are trusted and treated in an open and positive attitude. For example, employees regularly discuss with managers about their viewpoints within development teams. This helps workers feel part of the wider team, strengthens employee engagement and commitment to the company. Secondly, team-working practices create a closer supervision and a flat hierarchy. A coaching style manager develops employees to manage themselves rather than to manage each task.Employee’s suggestions are offered, and this contributes to improvements in organizational performance. An example of Tarmac targets and measures a decline in waste. In 2010, eighteen workshop-training sessions were held for all site employees on CO2 awareness and energy. All district managers were involved in the programme. Some external experts from Carbon Trust were also invited to support the rollout o f the training programme. As a result, Tarmac gained benefit from 500 energy and CO2 reduction. Overall, Tarmac adopted a high commitment strategy to meet the objectives.Therefore, it improved the company’s performance. * A small-medium size company – i-LEVEL i-Level is one of the most innovative digital media companies and is ranked the ‘Sunday Times 100 best companies to work for’ in 2004. It has a size of workforce of 60 employees. The i-Level company has a high level of financial performance. There was a 33 per cent increase in earnings per annum. Their guiding principles are used as a framework. This is to ensure the internal fit and the external fit of company. The company is at the growing stage which a lot of the recruitment effort is on discovering the potential staff. -Level frequently seeks appropriate employees to be supported to work with the company. To fit HR policies and practices together, i-Level uses physical arrangements to remove top-d own hierarchy in order to encourage employees’ participation, communication, creativity, self-managed teams and organisational values. As a result, a complete, open plan office is the environment where employees conduct their normal day-to-day operations. Moreover, i-Level sees pay is significant for performance. 15 per cent of the company’s pre-tax profit is kept for performance bonuses from 2003 to 2004.Meanwhile, the company argues pay is not their primary motivating force. On the other hand, the company aligns with business strategy and external environment by providing training courses for technical skills in media advertising. The company also offers an unusual training budget. There is an annual allowance provided for personal training and development purposes that are no obvious relation with work. The belief is to develop the skills and interests of workers in ways not studied before. This is expected to enhance i-level workers’ innovative thoughts at w ork through practices outside the company’s work area.To summaries, i-LEVEL achieves competitive advantage through innovation and which competes in very tight labour markets. It adopted Porter’s strategic option of ‘Focus’ and Pfeffer’s 7 practices to enhance the company's performance. Additional issues to reflect * Problems of implementation Line managers are central HRM performers in the organization, and they play a vital role in implementation of HR policies and practices. They influence their team‘s performance in a direct manner. A number of factors account for the line management problem. Firstly, it seems there is devolution to line managers.For instance, line managers do not want the responsibility of being a line manager or do not have enough time to deal with it accurately. They might not have the skills to handle HR issues successfully or are unaware of recent developments in view of HRM. Some managers do not consider a long-term v iew of the company or are inefficient for making policy in this area. Secondly, McGovern et al (1997), Marchington (2001) and Hutchinson and Purcell (2003) identify there are differences between ‘espoused’ and ‘actual’ policies that are relatively recognized to line managers.For example, some policies are normative rather than positive. Some descriptions of policies and practices are in general terms rather than analytical about actual situations. Hence, managers are unable to implement them specifically to meet the company’s goals. Furthermore, a broader issue, the line manager jobs in firms become progressively complex due to new firms’ structures. For instance, virtual and network companies have less clear line manager characters than the layered hierarchical company. One observable implication is pressure for reducing the size of the HR department.There will be a cut down in numbers of HR professionals. Ultimately, these factors all affect the organizational performance due to unsuccessful implementation of HR policies and practices. * Problems of measurement Fitzgerald (1991) and Neely (1998) stated that performance measurement is a key issue in guaranteeing the effective implementation of a firm’s strategy. However, using inadequate measurements is poor in supporting managements’ business objectives. The followings are the circumstances. Scientists use large-scale data groups made self-completed questionnaires.This will lead to two problems. First of all, there is dependence on one person, to represent the whole group. Secondly, there is dependence on a design of questionnaires. For example, respondents are answering yes or no questions rather than giving thoughts and opinions. This type of questions may generate a less accurate result. Moreover, there is uncertainty of how the data should be gathered, presented and analysed. The major problem is mis-reporting single respondents. Respondents may have limited knowledge of the area and use of policies.Furthermore, the measures of performance commonly take account of the financial performance, whereas there is a few findings focus on the broader issue of employee attitudes and well-being. Equally, there are matters to the range of HR practices. For instance, a report shows statistics of whether a company has self-managed teams, some may look at the proportion of workers running in a self-managed team. Lastly, Atkinson (2005) suggests that the measurement of productivity in the service sector can be exceptionally challenging.It is always easy to get typical, comparable financial statistics. To sum up, the measurement of data are related to the level of relevance to business performance. Critical analysis of the beyond * Best practice Pros ; Cons Research states there is a positive link between the HR practices and organisational performance. Firstly, Huselid (1995, p. 667) discovered that ‘the degree of returns for investments in High Performance Work Systems is significant’. In fact, ‘A one standard deviation rise in High Performance Work Systems practices is associated with a comparative 7. 5 per cent drop in labour turnover. On ‘per employee’ base, $27,044, $18,641 and $3814 more in sales, more in market value and profits respectively. Secondly, the workplace employee relation survey (Cully et al 1999) indicates that there is 14 per cent of organisations adopted high commitment strategy. In contrast, researcher (Delery 1998) also emphasized ‘deadly’ bundles of practices need to be avoided. For example, it occurs to managers giving reward based on individual performance while they are working as a team.Furthermore, Boxall and Purcell (2003, p. 64) commented while multi-national companies make the effort standardise their practices across nations, national perspective and organisational sectoral perspectives show criticism on the effectiveness of these practices. M archington and Grulis (2000, p. 1117) argue the most common example is in labour intensive organisations recognise costs are expensive when they use these practices. To summaries the best practice approach, Guest’s (1987) argues that there is no best practice.At the same time, he also suggests a set of best practices such as high commitment management is the route to survival of UK business. This leads to an argument that in order to enhance company performance, managers must alter their HR policies and practices to the framework that is operational. The interpretation comes to ‘best-fit’ approach. * Best-fit Pros ; Cons Thompson (2000) conducted two studies of firms in the UK aerospace industry. His first study in 1997 showed that with higher levels of value added per worker encourages greater diffusion of innovative working practices with their non-management employees.These organisations are towards to more heavily engaged in specialist production for niche ma rkets and hired technical and professional workers. The second study in 1999 showed evidence that organizations introduced a larger number of high performance work practices had much enhanced business performance. As a result, companies moving from less than five to more than six innovative practices created a 34 per cent increase in value added per worker. On the other hand, Miles and Snow (1984) align suitable managerial types to three genetic strategies of prospector, defender and analyser.If managerial properties and skills are aligned to company strategy, there will be a higher level of link to organisational performance. Thomas and Ramaswamy (1996) offered such support. As a result, performance in aligned firms was statistically excellent. In comparison, (Purcell 1999 p. 35) outlines that a number of successful organisations features that are unable to model. These are the cultural norms that have been developed gradually over a long period associated with accomplishment. It i s easy to identify the key factors that drive to success. Especially when the organisations are large and complex.Imaginably the major problem is that many organisations exist inside complex external environments with multiple contingencies that are not to be ignored or recognized. * Comparing both approaches Each approach has advantages evidence and disadvantages evidence. It could be argued that different approaches can apply in different sectors. For example, Guest (2001) advocates that there is the possibility that a high commitment management is most applicable in manufacturing i. e. Tarmac, while strategic choice for fitting with business strategy, is more credible in the service sector i. . i-LEVEL. As a whole, critically discuss the link between SHRM and performance. Evidence from Patterson et al (1997) examined sixty-seven manufacturing businesses in the UK for a period. The outcomes were 19 per cent of profitability and 18 per cent of the variation in productivity could be certified to HRM practices. This demonstrated HRM practices has a positive impact on organisational performance. Conclusion In summary, SHRM consists of a number of practices and is an organization level analysis of how HRM systems impact on performance.Two theoretical perspectives outline different views. The ‘best-practice’ approach defines there is ‘one best way’ of managing people. It is appropriate across all circumstances. Whereas ‘best-fit’ approach terms the best to manage people will change depending on organizational circumstances. It highlights the essence of linking business strategy. Tarmac was used as an example. It applied the ‘best practice’ approach and adopted a high commitment strategy to meet the objectives. Hence Tarmac improved its firm’s performance.I-Level was used an example to describe the competitive advantage the company had achieved through innovation while competing in extremely tight labour ma rket. It adopted Porter’s strategic option of ‘Focus’ and Pfeffer’s 7 practices to enhance the firm’s performance. Empirical evidences show both organisations are successful with adopting different approaches to their specific, targeted firms. These firms had a positive impact on performance. This can be concluded that SHRM has a clear link to business performance practically. In depth, other issues such as implementation and measurement roblems are considered. Problems of implementation affect the organizational performance due to unsuccessful implementation of HR policies and practices in line management. On the other hand, problems of measurement are valued on the basis of how easy and difficult the data is to represent and most importantly the level of relevance to business performance. If the relevance is slight, it may have little or no impact on business performance. In the final stage of comparing both approaches, many researchers’ po int of views is gathered. ‘Best-practice’ approach has advantages and disadvantages.It seems to argue that high commitment management is the route to successful business performance. On the other hand, the advantages and disadvantages of ‘best-fit’ approach suggest that applying this approach can be rigid and inflexibility due exists of complex external environments. Furthermore, in recent arguments, the product labour market seems to be emerged to a new post-industrial age where employers will tend to hire self-employed workers to carry out specific, time-limited projects for companies. This is due to the prediction of radical change.It can lead to a view that ‘best-fit’ approach should to be managed appropriately. This means practices should be adequate in different company’s life-cycle stage and align with different strategies. So that, it can feasibly enhance the organizational performance. Finally, strategic human resources manageme nt gives evidences, views, researches and facts to enhance organizational performance. However, the degree of high performance in context varies in different organizations under their circumstances. Hence, it does not necessary impact to ‘high’ performance.

Biodegradation of Hydrocarbons from Crude Oil by Pseudomonas Putida

Biodegradation of Hydrocarbons from Crude Oil by Pseudomonas putida A Project done under the guidance of Dr. K. Bharathi Department of Biotechnology. Submitted to the faculty Of Department of Biotechnology National Institute Of Technology, Warangal (A. P) Submitted By Febin P. Nalpady, Anzal Rahman, Shruti Sharma, Sindhuja Nandiraju, Giraboina Kranthi Kumar NATIONAL INSTITUTE OF TECHNOLOGY WARANGAL (A. P) (DEEMED UNIVERSITY) 2010-2011 DEPARTMENT OF BIOTECHNOLOGY NATIONAL INSTITUTE OF TECHNOLOGY, WARANGAL (A. P) CERTIFICATE This is to certify that the project entitled â€Å"†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. † carried out by †¦.. , bearing roll no. †¦. ,, final year B. Tech, Biotechnology, during academic year 2010-2011, is a bonafide work submitted to the National Institute of Technology, Warangal in partial fulfillment of the requirements for the requirements for the award of the Degree of Bachelor of Technology. Guide : Dr. K Bharathi Dept. of Biotechnology NIT Warangal ACKNOWLEDGEMENT With great pleasure and deep sense of gratitude, we take this opportunity to express our sense of indebtedness to Dr. K Bharathi, our project guide for accepting us under her good self to carry out this project work, and providing us his invaluable guidance and constant encouragement at each and every step throughout the progress of this project. To be sincere it was an inextinguishable treasure of pleasure for us to work under her excellent guidance. I would also like to thank the faculty of our department,Dr. P Sreenivasa Rao, Mr. Onkara Perumal and Mr. K. Narasimhulu. They were a pillar of strength for us and encouraged us to do our best. Name Roll no Table of Contents 1. Abstract 2. Introduction 2. 1 Bioremediation 2. 2 The conventional techniques of remediation 2. 3 Advantages of Bioremediation 2. 4 Microbes that are useful for bioremediation 3. Review of literature 3. 1 Microbial degradation 3. 2 Biodegradation of petroleum hydrocarbons 3. 3 Factors affecting Degradation 3. 4 Mechanism of Petroleum Hydrocarbon Degradation 4. Brief outline of the project work 5. Materials and Methods 5. 1 Preparation Of Nutrient Broth 5. 2 Preparation of Nutrient Agar Slants from the Bacterial Strain 5. Preparation of SubCultures of Bacterial Strain 5. 4 Centrifugation of Crude Oil 5. 5 Subculturing Of Petri Plates with oil 5. 6 Biodegradation Studies 5. 7 Gravimetric Analysis 6. Results 6. 1 Growth Analysis of Pseudomonas Putida 6. 2 Gravimetric Analysis 7. Discussion 8. References 1. ABSTRACT Oil spills have become a serious problem with the ever-increasing re source exploitation, transportation, storage, and accidental leakage of oil. Several techniques, including physical, chemical, and biological methods, are used to recover spilled oil from the environment. Bioremediation is a promising option for remediation since it is effective and economic in removing oil with less undue environmental damages. However, it is a relatively slow process and the degree of success depends on a number of factors. These factors include the existence of a microbial population capable of degrading the pollutants, the availability of contaminants to the microbial population and the environment factors are type of soil, temperature, pH, the presence of oxygen and nutrients. This project aims to study the degradation extent of the pseudomonas putida on oil. The microbial strain used is procured from NCL pune. 2. Introduction In quantitative terms, crude oil is one of the most important organic pollutants in marine environment and it has been estimated that worldwide somewhere between 1. 7- 8. 8? 106 tons of petroleum hydrocarbons impact marine waters and estuaries annually. Reports have been appearing since last three decades on the biodegradability of crude oil by bacteria which can use hydrocarbons as source of carbon and energy. A way to mitigate the effects of oil spills is bioremediation. 2. 1 Bioremediation It is a process by which chemical substances are degraded by bacteria and other microorganisms. The use of these microorganisms has been successfully applied for the treatment of waste and wastewater in controlled systems. Several research studies have recently been performed to investigate the use of bioremediation for oil-spill cleanup in seawater, freshwater and terrestrial areas. The technique has been found to have a potential for broad applications in terrestrial and freshwater environments for treating soils and sediments contaminated with oil and other substances, as well as for coastal environments impacted by oil spills. Water is a more sensitive medium than soil and requires different remediation techniques. Spills to surface water are easier to clean up than spills to groundwater, for obvious reasons. It is not only much harder to see the extent of the contamination, but also to remove the source of the contamination as, for example, a leaking underground storage tank. 2. 2. The conventional techniques of remediation . The conventional techniques used for remediation have been to dig up contaminated soil and remove it to a landfill, or to cap and contain the contaminated areas of a site. The methods have some drawbacks. The first method simply moves the contamination elsewhere and may create significant risks in the excavation, handling, and transport of hazardous material. Additionally, it is very difficult and increasingly expensive to find new landfill sites for the final disposal of the material. A better approach than these traditional methods is to completely destroy the pollutants if possible, or at least to transform them to innocuous substances. Some technologies that have been used are high-temperature incineration and various types of chemical decomposition (e. g. , base-catalyzed dechlorination, UV oxidation). They can be very effective at reducing levels of a range of contaminants, but have several drawbacks, principally their technological complexity, the cost for small-scale application, and the lack of public acceptance, especially for incineration that may increase the exposure to contaminants for both the workers at the site and nearby residents. . 3 Advantages of Bioremediation Bioremediation is an option that offers the possibility to destroy or render harmless various contaminants using natural biological activity. As such, it uses relatively low-cost, low-technology techniques and can often be carried out on site. It will not always be suitable, however, as the range of contaminants on which it is effective is limited, the timescales involved are relatively long, and the residual contaminant levels achievable ma y not always be appropriate. Although the methodologies employed are not technically complex, considerable experience and expertise may be required to design and implement a successful bioremediation program, due to the need to thoroughly assess a site for suitability and to optimize conditions to achieve a satisfactory result. Because bioremediation seems to be a good alternative to conventional clean-up technologies research in this field, especially in the United States, rapidly increasing. Bioremediation has been used at a number of sites worldwide, including Europe, with varying degrees of success. Techniques are improving as greater knowledge and experience are gained, and there is no doubt that bioremediation has great potential for dealing with certain types of site contamination. Unfortunately, the principles, techniques, advantages, and disadvantages of bioremediation are not widely known or understood, especially among those who will have to deal directly with bioremediation proposals, such as site owners and regulators. 2. 4 Microbes that are useful for bioremediation The biodegradation of petroleum in the marine environment is carried out largely by diverse bacterial populations, including various Pseudomonas species. The hydrocarbon-biodegrading populations are widely distributed in the world’s oceans; surveys of marine bacteria indicate that hydrocarbon-degrading microorganisms are ubiquitously distributed in the marine environment. Generally, in pristine environments, the hydrocarbon-degrading bacteria comprise < 1% of the total bacterial population. These bacteria presumably utilize hydrocarbons that are naturally produced by plants, algae, and other living organisms. They also utilize other substrates, such as carbohydrates and proteins. When an nvironment is contaminated with petroleum, the proportion of hydrocarbon-degrading microorganisms increases rapidly. In particular, in marine environments contaminated with hydrocarbons, there is an increase in the proportion of bacterial populations with plasmids containing genes for hydrocarbon utilization. The proportion of hydrocarbon-degrading bacterial populations in hydrocarbon-contaminated marine environments often exceed 10% of the tot al bacterial population 3. Review of Literature 3. 1 Biodegradation of petroleum hydrocarbons Biodegradation of petroleum hydrocarbons is a complex process that depends on the nature and on the amount of the hydrocarbons present. Petroleum hydrocarbons can be divided into four classes: the saturates, the aromatics, the asphaltenes (phenols, fatty acids, ketones, esters, and porphyrins), and the resins (pyridines, quinolines, carbazoles, sulfoxides, and amides) [R. R. Colwell, J. D. Walker, and J. J. Cooney, â€Å"Ecological aspects of microbial degradation of petroleum in the marine environment,]. Di? erent factors in? uencing hydrocarbon degradation have been reported by Cooney et al. One of the important factors that limit biodegradation of oil pollutants in the environment is their limited availability to microorganisms. Petroleum hydrocarbon compounds bind to soil components, and they are difficult to be removed or degraded [S. Barathi and N. Vasudevan], â€Å"Utilization of petroleum hydrocarbons by Pseudomonas ? uorescens isolated from a petroleum-contaminated soil]. Hydrocarbons di? er in their susceptibility to microbial attack. The susceptibility of hydrocarbons to microbial degradation can be generally ranked as follows: linear alkanes > branched alkanes > small aromatics > cyclic alkanes [J. J. Perry, â€Å"Microbial metabolism of cyclic alkanes,† in Petroleum Microbiology]. Some compounds, such as the high molecular weight polycyclic aromatic hydrocarbons (PAHs), may not be degraded at all. 3. 2 Microbial degradation Microbial degradation is the major and ultimate natural mechanism by which one can cleanup the petroleum hydrocarbon pollutants from the environment [1-3] The recognition of biodegraded petroleum-derived aromatic hydrocarbons in marine sediments was reported by[ Jones et al]. They studied the extensive biodegradation o alkyl aromatics in marine sediments which occurred prior to detectable biodegradation of n-alkane pro? e of the crude oil and the microorganisms, namely, Arthrobacter, Burkholderia, Mycobacterium, Pseudomonas, Sphingomonas, and Rhodococcus were found to be involved for alkylaromatic degradation. Microbial degradation of petroleum hydrocarbons in a polluted tropical stream in Lagos, Nigeria was reported by Adebusoye et al. Nine bacterial s trains, namely, Pseudomonas ? uorescens, P. aeruginosa, Bacillus subtilis, Bacillus sp. , Alcaligenes sp. , Acinetobacter lwo? ,Flavobacteriumsp. , Micrococcus roseus, and Corynebacterium sp. were isolated from the polluted stream which could degrade crude oil. Hydrocarbons in the environment are biodegraded primarily by bacteria, yeast, and fungi. The reported e? ciency of biodegradation ranged from 6% to 82% for soil fungi, 0. 13% to 50% for soil bacteria, and 0. 003% to 100% [6] for marine bacteria. Many scientists reported that mixed populations with overall broad enzymatic capacities are required to degrade complex mixtures of hydrocarbons such as crude oil in soil, fresh water, and marine environments [8]. Bacteria are the most active agents in petroleum degradation, and they work as primary degraders of spilled oil in environment [7]. Several bacteria are even known to feed exclusively on hydrocarbons [9]. Floodgate [36] listed 25 genera of hydrocarbon degrading bacteria and 25 genera of hydrocarbon degrading fungi which were isolated from marine environment. A similar compilation by Bartha and Bossert [6] included 22 genera of bacteria and 31 genera of fungi. In earlier days, the extent to which bacteria, yeast, and ? lamentous fungi participate in the biodegradation of petroleum hydrocarbons was the subject of limited study, but appeared to be a function of the ecosystem and local environmental conditions [7]. Crude petroleum oil from petroleum contaminated soil from North East India was reported by Das and Mukherjee . Acinetobacter sp. Was found to be capable of utilizing n-alkanes of chain length C10–C40 as a sole source of carbon [6]. Bacterial genera, namely, Gordonia, Brevibacterium, Aeromicrobium, Dietzia, Burkholderia, and Mycobacterium isolated from petroleum contaminated soil proved to be the potential organisms for hydrocarbon degradation [9]. The degradation of poly- aromatic hydrocarbons by Sphingomonas was reported by Daugulis and McCracken . Fungal genera, namely, Amorphoteca, Neosartorya, Talaromyces, and Graphium and yeast genera, namely, Candida, Yarrowia, and Pichia were isolated from petroleum contaminated soil and proved to be the potential organisms for hydrocarbon degradation [ Singh et al. ] also reported a group of terrestrial fungi, namely, Aspergillus, Cephalosporium, and Pencillium which were also found to be the potential degrader of crude oil hydrocarbons. The yeast species, namely, Candida lipolytica, Rhodotorula mucilaginosa, Geotrichum sp, and Trichosporon mucoides isolated from contaminated water were noted to degrade petroleum compounds [5]. Though algae and protozoa are the important members of the microbial community in both aquatic and terrestrial ecosystems, reports are scanty regarding their involvement in hydrocarbon biodegradation. [Walker et al. ] isolated an alga, Prototheca zop? which was capable of utilizing crudeoil and a mixed hydrocarbon substrate and exhibited extensive degradation of n-alkanes and isoalkanes as well a aromatic hydrocarbons. Cerniglia et al. observed tha nine cyanobacteria, ? ve green algae, one red alga, one brown alga, and two diatoms could oxidize naphthalene. Protozoa by contrast, had not been shown to utilize hydrocarbons. 3. 3 Factors affecting Degradation A number of limiting factors have been recognized to a? ect the biodegradation of petroleum hydrocarbons, many of which have been discussed by Brusseau. The composition and inherent biodegradability of the petroleum hydrocarbon pollutant is the ? rst and foremost important consideration when the suitability of a remediation approach is to be assessed. Among physical factors, temperature plays an important role in biodegradation of hydrocarbons by directly a? ecting the chemistry of the pollutants as well as a? cting the physiology and diversity of the microbial ? ora. Atlas [4] found that at low temperatures, the viscosity of the oil increased, while the volatility of the toxic low molecular weight hydrocarbons were reduced, delaying the onset of biodegradation. Temperature also a? ects the solubility of hydrocarbons [8]. Although hydrocarbon biodegradation can occur over a wide range of temperatures, the rate of biodegradation generally decreases with the decreasing temperature. shows that highest degradation rates that generally occur in the range 30–40? C in soil environments, 20–30? Cin some freshwater environments and 15–20? C in marine environments . Venosa and Zhu [11] reported thatambient temperature of the environment a? ected both the properties of spilled oil and the activity of the microorganisms. Signi? cant biodegradation of hydrocarbons have been reported in psychrophilic environments in temperate regions. Nutrients are very important ingredients for successful biodegradation of hydrocarbon pollutants especially nitrogen, phosphorus, and in some cases iron [8]. Some of these nutrients could become limiting factor thus a? ecting the biodegradation processes. Atlas [11] reported that when a major oil spill occurred in marine and freshwater environments, the supply of carbon was signi? cantly increased and the availability of nitrogen and phosphorus generally became the limiting factor for oil degradation. In marine environments, it was found to be more pronounced due to low levels of nitrogen and phosphorous in seawater [10]. Freshwater wetlands are typically considered to be nutrient de? cient due to heavy demands of nutrients by the plants. Therefore, additions of nutrients were necessary to enhance the biodegradation of oil pollutant. On the other hand, excessive nutrient concentrations can also inhibit the biodegradation activity [11]. Several authors have reported the negative e? ects of high NPK levels on the biodegradation of hydrocarbons especially on aromatics [10]. The e? ectiveness of fertilizers for the crude oil bioremediation in subarctic intertidal sediments was studied by Pelletier et al. . Use of poultry manure as organic fertilizer in contaminated soil was also reported , and biodegradation was found to be enhanced in the presence of poultry manure alone. Maki et al. eported that photo-oxidation increased the biodegradability of petroleum hydrocarbon by increasing its bioavailability and thus enhancing microbial activities. 3. 4 Mechanism of Petroleum Hydrocarbon Degradation The most rapid and complete degradation of the majority of organic pollutants is brought about under aerobic conditions. Figure 2 shows the main principle of aerobic degradation of hydrocarbons [11]. The initial intracellular at tack of organic pollutants is an oxidative process and the activation as well as incorporation of oxygen is the enzymatic key reaction catalyzed by oxygenases and peroxidases. Peripheral degradation pathways convert organic pollutants step by step into intermediates of the central intermediary metabolism, for example, the tricarboxylic acid cycle. Biosynthesis of cell biomass occurs from the central precursor metabolites, for example, acetyl-CoA, succinate, pyruvate. Sugars required for various biosyntheses and growth are synthesized by gluconeogenesis. The degradation of petroleum hydrocarbons can be mediated by speci? c enzyme system. Figure 3 shows the initial attack on xenobiotics by oxygenases. Other mechanisms involved are (1) attachment of microbial cells to the substrates and (2) production of biosurfactants [12]. The uptake mechanism linked to the attachment of cell to oil droplet is still unknown but production of biosurfactants has been well studied. 4. Brief outline of the project work: 1. Procurement of oil Samples. 2. Procurement of Pseudomonas putida strain. 3. Sub-culturing the microbe in nutrient rich media for checking viability.. 4. Culturing microbes on a mineral salt media containing only crude oil as a carbon source. 5. Biodegradation studies. 6. Gravimetric analysis 5. Materials and Methods Soil Samples – Samples(500g) contaminated with oil used for hydrocarbons utilizing microorganisms, were collected from Nhava Sheva port in Mumbai(where a recent oil spill has took place). Crude Oil – Crude Oil is procured from an Oil production site of ONGC. Bacterial Strain – Pseudomonas Putida PS-I strain procured from NCL Pune. 5. 1 Preparation Of Nutrient Broth For preparation of nutrient agar, malt extract, yeast extract, Potassium dihydrogen phosphate and dextrose is required. Malt extract and yeast extract is generally used as a nutritious agent. Potassium dihydrogen phosphate i. . KH2PO4 is used as a buffering agent to maintain the pH. Dextrose is generally used as a carbon source because dextrose inhibits the growth of other micro-organisms. AUTOCLAVE is a device to sterilize equipment and supplies by subjecting them to high pressure steam at 121 ° C or more. Machines in this category largely operate by utilizing pressurized steam and superheated water. To sterilize culture media, rubber material, gowns, dressing, gloves etc. are used. It is particularly useful for materials which cannot withstand the higher temperature of hot air oven. CHEMICALS REQUIRED:- For 1000ml, Malt extract — 10 gm Beef Extract — 4 gm K2HPO4 — 1 gm Magnesium sulphate — 1 gm Sodium Chloride — 0. 5 gm pH — 7. 0 Agar — 15% PROCEDURE:- For preparation of 100ml of nutrient broth, around 100ml of double distilled water was taken in a conical flask. Malt extract, yeast extract, KH2PO4 and dextrose was weighed as per the composition mentioned above and added to the conical flask. The conical flasks are to be shaken so well so that all the chemicals should dissolve. pH was checked using pH meter and adjusted to 7. 0 using NaOH and HCl. The volume was made to 100ml by adding double distilled water. The above solution i. e. nutrient agar along with the Petri-plates was autoclaved at 15 psi and 15 minutes. Now the solution was allowed to cool down to ready to pour condition. PRECAUTIONS:- The autoclave should be done at 15 psi and 15 min. The pH should be maintained at 7. 0. 5. 2 Preparation of Nutrient Agar Slants from the Bacterial Strain For the preparation of Slants, Flame the inoculating loop to redness by holding it pointed down into the flame, starting near the handle and then moving the loop into the flame. This technique sterilizes the loop and, if wet with a culture, heats up the loop without spattering bacteria into the air and onto the surrounding area. Let the loop cool a minute. A hot loop will damage the bacteria cells. Using the fingers of the â€Å"loop hand† remove the cap from the stock culture tube and flame the tube mouth. Do not set the tube top down on the table. Insert the cooled sterilized loop into the culture tube being careful to not touch the sides of the tube. Touch the loop to the culture. You need not scrape a visible amount from the culture. Hold the tube as horizontal as possible to preclude particles from the air settling into the tube But do watch out for any condensate in the bottom of slant cultures. Don't let this fluid wash across the face of the culture. Remove the loop being careful again to not touch the tube sides. Flame the tube mouth and replace the cap. Remove the cap of the broth tube. Flame the top. Remember to hold the top in your fingers. Insert the loop into the Slant tube filled with agar and shake to remove the bacteria. Withdraw the loop, flame the tube mouth and replace the cap. Resterilize the inoculating loop and place it on the table. Never place a contaminated loop on the table. If there is any liquid in the bottom of the slant tube avoid sticking the loop into this condensate. 5. 3 Preparation of SubCultures of Bacterial Strain The Nutrient Broth Cultures are inoculated with the bacterial strain from the nutrient agar slant as detailed below. PROCEDURE Light your Bunsen burner. In one hand hold both the Nutrient Broth culture to be inoculated and the nutrient slant agar. Loosen the tube caps. In your other hand hold the inoculating loop. Flame the inoculating loop to redness by holding it pointed down into the flame, starting near the handle and then moving the loop into the flame. This technique sterilizes the loop and, if wet with a culture, heats up the loop without spattering bacteria into the air and onto the surrounding area. Let the loop cool a minute. A hot loop will damage the bacteria cells. Using the fingers of the â€Å"loop hand† remove the cap from the stock culture tube and flame the tube mouth. Do not set the tube top down on the table. Insert the cooled sterilized loop into the slant tube being careful to not touch the sides of the tube. Touch the loop to the culture. You need not scrape a visible amount from the culture. Hold the tube as horizontal as possible to preclude particles from the air settling into the tube But do watch out for any condensate in the bottom of slant cultures. Don't let this fluid wash across the face of the culture. Remove the loop being careful again to not touch the tube sides. Flame the tube mouth and replace the cap. Remove the cap of the broth tube. Flame the top. Remember to hold the top in your fingers. Insert the loop into the broth and shake to remove the bacteria. Gently shake the broth culture. This inoculated broth culture is incubated at room temperature for 72 hours and the bacteria is allowed to grow in the broth medium. 5. 4 Centrifugation of Crude Oil Centrifugation is a process that involves the use of the centrifugal force for the separation of mixtures with a centrifuge, used in industry and in laboratory settings. More-dense components of the mixture migrate away from the axis of the centrifuge, while less-dense components of the mixture migrate towards the axis. The precipitate (pellet) gathers on the bottom of the tube. The remaining solution is properly called the â€Å"supernate† or â€Å"supernatant liquid† The Crude Oil is Centrufuged at a speed of 5000 rpm for a period of ten minutes. The Contaminants in the oil are collected at the bottom of the tube in the form of pellets. These pellets can be removed by filtration using a filter paper. Now the concentrates oil which is free from impurities is collected in a flask and gently shaken. Spectophotometric Analysis Optical density, measured in a spectrophotometer, can be used as a measure of the concentration of bacteria in a suspension. As visible light passes through a cell suspension the light is scattered. Greater scatter indicates that more bacteria or other material is present. The amount of light scatter can be measured in a spectrophotometer. Typically, when working with a particular type of cell, you would determine the optical density at a particular wavelength that correlates with the different phases of bacterial growth. Generally we will want to use cells that are in their mid-log phase of growth. Typically the OD600 is measured. 5. 5 Subculturing Of Petri Plates with oil % of crude oil is mixed with 100 ml of Nutrient broth medium. The 1. 5g of agar is added to the medium and Nutrient Agar(with 1% crude oil) is prepared. Now take 6 Petri dishes. Open one of the dishes. Take the nutrient agar to be added and Swab the agar, barely pressing, side to side on the entire surface. The dish is closed immediately after swabbing to prevent contamination. The dish is sealed with tape around the edges to prevent co ntamination. Repeat the same procedure for the other dishes. Put the dishes in an incubator for 4 days to allow some growth. 5. 6 Biodegradation Studies Laboratory Biodegradation studies were carried out under optimized conditions for assessing the biodegradation potential of the pseudomonas putida PS-I Strain. After the desired interval of time, the petriplates were taken out and the bacterial activities were stopped by adding 1% N HCl. For the extraction of crude oil from these plates, 50ml of culture broth was mixed with 50 ml of acetone : petroleum ether (1:1) in a single separating funnel and shaken vigorously to get a single emulsified layer and acetone was added then to it and shaken gently to break the emulsification which resulted in three layers. Top layer was a mixture of Petroleum ether crude oil and acetone. Clumping cells aere formed in the middle layer and the bottom layer contains acetone, water and biosurfactant in soluble form. The lower two layers were separated out while the top layer containing petroleum ether mixed with crude oil and acetone is taken out in a fresh beaker. The extracted oil is passed through anhydrous sodium sulphate in order to remove the moisture. The petroleum ether and acetone were evaporated on a water bath leaving us with the dry oil clump. 5. 7 Gravimetric Analysis Gravimetric analysis describes a set of methods in analytical chemistry for the quantitative determination of an analyte based on the mass of a solid. the analyte must first be converted to a solid by precipitation with an appropriate reagent. The precipitate can then be collected by filtration, washed, dried to remove traces of moisture from the solution, and weighed. The amount of analyte in the original sample can then be calculated from the mass of the precipitate and its chemical composition. Gravimetric analysis is performed on the dry oil clump collected after the water bath. It is done by weighing the quantity of residual oil left after biodegradation in a tared vial. The mass of this crucible is subtracted from the initial mass of the 1% of oil that is added in the petridishes giving the amount of oil that is degraded due to the biological avtivity of the pseudomonas putida strain. 6. Results 6. 1 Growth Analysis of Pseudomonas Putida: The culture which was obtained in test tube slants was further sub cultured in conical flasks in a LB medium and the growth analysis was done to check the viability of the culture obtained. The growth kinetics plot was obtained by measuring the O. D. y using a visible spectrophotometer and recording the reading at regular intervals. The Graph was then plotted. 6. 2 Gravimetric Analysis: Biodegradation studies were conducted for 15 days and gravimetric analysis was done after every five days. The biodegradation effect was seen from the 5th day onwards. Laboratory biodegradation studies on crude oil by Pseudomonas putida No . Of Days| Initial Concn| Final Concn| Difference| Degradation (%)| 5 days| 1. 431  ± . 57| 1. 325  ± . 46| 0. 106  ± . 11| 7. 4| 10 days| 1. 453  ± . 71| 1. 198  ± . 38| 0. 255  ± . 34| 17. 54| 15 days| 1. 398  ± . 68| 0. 936  ± . 31| 0. 62  ± . 28| 33. 04 | 7. Discussion It can be seen that the degradation percentage of oil has increased from mere 7. 41 in the first 5 days to a good 33. 04 percentage towards the 15th day, from this it is clearly understood that pseudomonas putida is an ideal organism for bioremediation programmes. Moreover this rate of degradation has been obtained under normal conditions without any aid from surfactants or fertilizers. Hence there is scope for achieving much greater rates by using the above mentioned methods of fertilizing or adding surfactants. 8. BIBLIOGRAPHY (1). U. S. Enviromental Protection Agency (1990). Interim Report, Oil Spill Bioremediation Project. U. S. 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