Key Performance Indicators Essay Example | Topics and Well Written Essays - 500 words

Key Performance Indicators - Essay Example According to the research findings, efficiency is about deploying the most optimal number of staff and serving the most number of customers at the least amount of time. while customer service is about being able to deliver on important customer service metrics like the order to fulfillment lead times, waiting times between customers, maximizing the size of the queue for both cars and dine-in customers, payment queues, the number of people served per table. Â  These twin concerns are of course of paramount concern for the firm, given that both impact profitability. Customer service affects the top-line revenues, in that the greatest number of people served results in the greatest amount of revenues for the firm, while efficiency metrics relating to the most efficient use of staff to serve the greatest amount of customers impact costs. When both costs and revenues are optimized, this results in the greatest possible bottom line results for the firm. In the case at hand, the KPIs are a rguably those that capture best the kind of efficiency and customer service gains that are optimal for the restaurant, and for these chosen KPIs the different shifts are measured. The simulation results detail many different KPIs that can potentially capture the most important data that serve the purpose of optimizing both revenues and costs as discussed above, and given the kinds of data collected for the different shifts, the choices were made based on what kind of metrics will yield the most in terms of optimizing both customer service levels and staffing levels. In the ideal case, the best shift to be chosen is one that employs the least amount of staff while at the same time maximizing customer service metrics that relate to the five KPIs chosen for this analysis. Without the KPIs, one would be inclined to choose that shift that employs the least amount of staff. Going the other extreme, the best shift would be the one that achieves the greatest customer service levels in terms of queue sizes and waiting times. Obviously, the latter impacts costs, while the former impacts customer service and therefore revenues. It is, therefore, a balance, and that balance is a function of the five KPIs chosen on the one hand and the staffing levels on the other.

The Slave Trade in Africa Essay Example for Free

The Slave Trade in Africa Essay Eric Williams thesis entitled Capitalism and slavery is not a study on the nature of the slave trade, but rather a study of the role of slavery in the English economy. In his thesis Williams proposes the idea that capitalism is a result of the Atlantic slave trade. Williams defines capitalism as when someone can use their resources to make a profit without that person actually being present. The Atlantic Slave Trade was then an example of capitalism. English investors gave funds to stock companies, such as the Dutch East Indian Company, who wound use those funds to purchase ships and trading goods. The stock companies would then hire a crew and send the ships to Africa where they would trade their goods for African Slaves. The ships would then transport the slaves to the Americas where they would sell their human cargo and purchase American goods. The ships could then return to England and sell their American goods for capital, then splitting the profit amongst the investors. In his thesis Williams asserts that these stock companies were the first examples of capitalism and that the capitalists systems which are present in the modern world are direct results of the Atlantic Slave Trade. It appears that Williams is correct in his thesis. While elements of capitalism, such as buying and selling of goods, were present prior to the slave trade, this was the first point in history when private investors combined their capital in the form of a company whose sole purpose was to increase that capital. At no point did the stock companies manufacture any new product instead these companies served only to buy and sell commodities in such a way as to increase the capital of their investors. Ancient Africa was characterized by strong states. Unlike Europe African states were well organized before the birth of Christ. However as European states became stronger African states weakened. These strong ancient African states such as, Egypt, Ethiopia, Kush and Benin, believed that the purpose of the state was to serve the people. This ideology made it possible for African states to become strong because since the state served the people the people were willing to participate in defending the state and submit to taxation in order to pro vide for the needs of the state which then benefited the individual. However African states began to weaken when the Arab came into Africa. In a quest to seek the destruction of Christianity in Europe the Arabs tore through the Maghreb (five north African countries). The Arabs not only took over the state, but also the culture, as a new Arab population settled, and pushed the original African population below the Sahara. The Arab presence in Africa soon led to a weakening of the African State. In 1350 the strong African state of Songhai began to have border disputes with the Arab led state Morroco. Songhai stated that the purpose of the African state was to serve the people to which Morroco replied that the purpose of the state was to serve Islam. Since the ruler of Morroco was a descendant of Mohammed that meant that it was Songhais responsibility to support the Morrocan state rather than the interests of its own people. Songhai was destroyed by Morroco in 1591, and after Songhais destruction any new states that emerged in this area put the interests of outsiders above the welfare of their own people. The area that had once been the strong empire of Songhai became the core of the slave trade in Africa. When Europeans came into Africa to trade they dealt with these weakened African states. They provided the states arms and the states allowed Europeans to enslave their citizens. African states allied with European nations at the expense of their own people; showing that the purpose of the African state had changed from serving its citizens to serving the interests of outsiders because the same sort of brutality used by Morroco in its destruction of Songhai was used by the Europeans in gunboat diplomacy. The African state would submit to foreign interests because it was no longer strong enough to fight back. African states could not compete against European technology so the rulers of these states signed agreements that allowed their people to be captured, enslaved and taken across the Atlantic. The weakening of the African state caused a change in the purpose of the State. The purpose of the state became providing for the needs and wants of foreigners; this is why the slave trade was possible in Africa. Not only did the African states allow its people to be enslaved, but the states participated in the enslavement of its own people in order to receive the benefits of trade with the Europeans.

Objectives of the Personnel Manager. :: Business and Management Studies

Objectives of the Personnel Manager. When the Personnel Manager is involved in recruiting new employees for the store he/she has to first has to look into the Internal and External Constraints. Whilst looking at this the Personnel Manager will have to decide weather the new recruit will stick to the terms of the job. As well as this the Personnel Manager will have to think if the new Member of the team will be able to fit in with the team at present or will he/she be subject to bullying or discrimination of any sort. As well as this aspect it could all be the other way round and the new employee may start to manipulate the other members of the team and start to bully and discriminate against them. Lastly the Personnel Manager will have to consult with the Finance Department and with the new employee on terms of - How much money he/she will get, How many sick days, How many days holiday etc. etc. The Objectives Of The Personnel Manager is to find ==================================================  · The right people at  · The right place at  · The right time with  · The right training. The Personnel manager has to find :- The Right people. This means that the Personnel Manager needs to find the right people for the job, this could mean that they need to have the right Qualities or Qualifications. Also these new people have to fit in with the way the business is currently run and the right attitude for this particular post of this job. The Right Place. This means that the chosen person must have the right post within the organisation. If the person is young and has never had a job, they will have to start off with a low post job and not in charge of anyone. Also you will have to know if the person is able to control over people. The right time. The new people have to have a job that will allow them to keep up with whatever commitments they have outside of work. i.e. if these people have young children they will have to be home early and come to work late so that they can meet their children. The Right Training. If these people are in a computer department they may need training to help them use particular software and programs as well as how to type efficiently. People may also need training if they are getting a promotion so they will need to know how to do things to a better standard, and they will probably be in control of more people

Contract and United Airlines

Cardillo Travel Systems, Inc. ACT 1 Russell Smith knew why he had been summoned to the office of A. Walter Rognlien, the 74-year-old chairman of the board and chief executive officer (CEO) of Smith’s employer, Cardillo Travel Systems, Inc. Just two days earlier, Cardillo’s in-house attorney, Raymond Riley, had requested that Smith, the company’s controller, sign an affidavit regarding the nature of a transaction Rognlien had negotiated with the United Airlines.The affidavit stated that the transaction involves $203,000 payment by United Airlines to Cardillo but failed to disclose why the payment was being made or for what specific purpose the funds would be used. The affidavit included a statement indicating that Cardillo’s stockholders’ equity exceeded $3 million, a statement that Smith knew to be incorrect. Smith also knew that Cardillo was involved in a lawsuit and that court injunction issued in the case required the company to maintain stockhol ders’ equity of at least $3 million.Because of the blatant misrepresentation in the affidavit concerning Cardillo’s stockholders’ equity and a sense of uneasiness regarding United Airlines’ payment to Cardillo, Smith had refused to sign the affidavit. When Smith stepped into Rognlien’s office on that day in May 1985, he found not only Rognlien but also Riley and two other Cardillo executives. One of the other executives was Esther Lawrence, the firm’s energetic 44-year-old persistent and chief operating officer (COO) and Rognlien’s wife and confidante. Lawrence, a long-time employee, had assumed control of Cardillo’s day-to-day operations in 1948.Rognlien’s two sons by a previous marriage had left the company in the early 1980s following a power struggle with Lawrence and their father. As Smith sat waiting for the meeting to begin, his apprehension mounted. Although Cardillo had a long and proud history, in recent years the company had begun experiencing serious financial problems. Founded in 1935 and purchased in 1956 by Rognlien, Cardillo ranked as the fourth-largest company in the travel agency industry and was the first to be listed on a national stock exchange. Cardillo’s annual revenues had steadily increased after Rognlien acquired the company, approaching $100 million by 1984.Unfortunately, the company’s operating expenses had increased more rapidly. Between 1982 and 1984, Cardillo posted collective losses of nearly $1. 5 million. These poor operating results were largely due to an aggressive franchising strategy implemented by Rognlien. In 1984 alone that strategy more than doubled the number of travel agency franchises operated by Cardillo. Shortly after the meeting began, the overbearing and volatile Rognlien demanded that Smith sign the affidavit. When Smith steadfastly refused, Rognlien showed him the first page of an unsigned agreement between United Airlines and Cardill o.Rognlien then explained that the $203,000 payment was intended to cover expenses incurred by Cardillo in changing from American Airlines’ Apollo system. Although the payment was intended to reimburse Cardillo for those expenses and was refundable to United Airlines if not spent, Rognlien wanted Smith to record the payment immediately as revenue. Not surprisingly, Roglien’s suggested treatment of the United Airlines payment would allow Cardillo to meet the $3 million minimum stockholders’ equity threshold established by the court order outstanding against the company.Without hesitation, Smith informed Rognlien that recognizing the United Airlines payment as revenue would be improper. At that point, â€Å"Rognlien told Smith that he was incompetent and unprofessional because he refused to book the united payment as income. Rognlien further told Smith that Cardillo did not need a controller like Smith who would not do what was expected of him†. ACT 2 In No vember 1985, Helen Shepherd, the audit partner supervising the 1985 audit of Cardillo by Touche Ross, stumbled across information in the client’s files regarding the agreement Rognlien had negotiated with United Airlines earlier that year.When Shepherd asked her subordinates about this agreement, one of them told her of a $ 203,000 adjusting entry Cardillo had recorded in late June. That entry, which follows, had been approved by Lawrence and was apparently linked to the United Airlines-Cardillo transaction: Dr ReceivablesUnited Airlines$203,210 Cr Travel Commissions and Fees203,210 Shepherd’s subordinates had discovered the adjusting entry during their second-quarter review of Cardillo’s form 10-Q statement. When asked, Lawrence explanation without attempting to corroborate it with other audit evidence.After discussing the adjusting entry with her subordinates, Shepherd questioned Lawrence. Lawrence insisted that the adjusting entry had been properly recorded. Shepherd than requested that Lawrence asks United Airlines to provide Touch Ross with a confirmation verifying the key stipulations of the agreement with Cardillo. Shepherd’s concern regarding the adjusting entry stemmed from information she had reviewed in the client’s files that the United Airlines payment to Cardillo was refundable under certain conditions and thus not recognizable immediately as revenue.Shortly after the meeting between Shepherd and Lawrence, Walter Rognlien contacted the audit partner. Like Lawrence, Rognlien maintained that the $203,000 amount had been properly recorded as commission revenue during the second quarter. Rognlien also told Shepherd that the disputed amount, which United Airlines paid to Cardillo during the third quarter of 1985, was not refundable to United Airlines under any circumstances. After some prodding by Shepherd, Rognlien agreed to allow her to request a confirmation from United Airlines concerning certain features of the agreement.Shepherd received the requested confirmation from United Airlines on December 17, 1986. The confirmation stated that the disputed amount was refundable through 1990 if certain stipulations of the contractual agreement between the two parties were not fulfilled. After receiving the confirmation, Shepherd called Rognlien and asked him to explain the obvious difference of opinion between United Airlines and Cardillo regarding the terms of their agreement with the chairman of the board of United Airlines. â€Å"Rognlien claimed that pursuant to this confidential business arrangement, the $203,210 would never have to repaid the United.Shepherd’s conversation with Rognlien refused. In fact, as Rognlien knew, no such agreement existed. † A few days following Shepherd’s conversation with Rognlien, she advised William Kaye, Cardillo’s vice president of finance, that the $203,000 amount could not be recognized as revenue until the contractual agreement wi th United Airlines expired in 1990. Kaye refused to make the appropriate adjusting entry, explaining that Lawrence had insisted that the payment from United Airlines be credited to a revenue account. On December 30, 1958, Rognlien called Shepherd and told her that he was terminating Cardillo’s relationship with Touche Ross.In early February 1986, Cardillo filled a form 8-K statement with the Securities and Exchange Commission (SEC) notifying that agency of the company’s change in auditors. SEC regulations required Cardillo to disclose in the 8-K statement any disagreements involving accounting, auditing, or financial reporting issues with its former auditor. The 8-K, signed by Lawrence, indicated that no such disagreements preceded Cardillo’s decision to dismiss Touche Ross. SEC regulations also required Touche Ross to draft a letter commenting on the existence of any disagreements with Cardillo.This letter had to be filed as an exhibit to the 8-K statement. In touche Ross’s exhibit letter, Shepherd discussed that the improper accounting treatment given that transaction resulted in misrepresented financial statements for Cardillo for the six months ended June 30, 1985, and the nine months ended September 30, 1985. In late February 1986, Raymond Riley, Cardillo’s legal counsel, wrote Shepherd and insisted that she had misinterpreted the United Airlines-Cardillo transaction in the Touch Ross exhibit letter filed with the company’s 8-K.Riley also informed Shepherd that Cardillo would not pay the $17,500 invoice that Touche Ross had submitted to his company. This invoice was for professional services Touche Ross had rendered prior to being dismissed by Rognlien. ACT 3 On January 21, 1986, Cardillo retained KMG Main Hurdman (KMG) to replace Touche Ross as its independent audit firm. KMG soon addressed the accounting treatment Cardillo had applied to the United Airlines payment. When KMG personnel discussed the payment with Rognlien, he informed them to the alleged secret arrangement with United Airlines that superseded the written contractual agreement.According to Rognlien, the secret arrangement precluded United Airlines from demanding a refund of the $203,000 payment under any circumstances. KMG refused to accept this explanation. Roger Shlonsky, the KMG audit partner responsible for Cardillo engagement, told Rognlien that the payment would have to be recognized as revenue on a pro rata basis over the five-year period of the written contractual agreement with United Airlines. Cardillo began experiencing severe liquidity problems in early 1986. These problems worsened a few months later when a judge imposed a $685,000 judgment on Cardillo to resolve a civil suit filed against the company.Following the judge? s ruling Raymond Riley alerted Rognlien and Lawrence that the adverse judgment qualified as a â€Å"material event† and thus has to be reported to the SEC in a Form 8-K filling. In the me morandum he sent to his superiors, Riley discussed the serious implications of not disclosing the settlement to the SEC: â€Å"My primary concern by not releasing such report and information is that the officers and directors of Cardillo may be subject to violation of rule 10b-5 of the SEC rules by failing to disclose information that may be material to a potential investor. Within 10 days of receiving Riley’s memorandum, Rognlien sold 100,000 shares of Cardillo stock in the open market. Two weeks later, Lawrence issued a press release disclosing for the first time the adverse legal settlement or that Cardillo remained viable only because Rognlien had invested in the company the proceeds from the sale of the 100,000 shares of stock. Additionally, Lawrence’s press release, Roger Shlonsky met with Rognlien and Lawrence. Shlonsky informed them that the press released grossly understated Cardillo’s estimated loss for fiscal 1985. Shortly after that meeting, KMG res igned as Cardillo’s independent audit firm.EPILOGUE In May 1987, the creditors of Cardillo Travel Systems, Inc. forced the company into involuntary bankruptcy proceedings. Later that same year, the SEC concluded a lengthy investigation of the firm. The SEC found that Rognlien, Lawrence, and Kaye had violated several provisions of the federal securities laws. These violations included making false representations to outside auditors, failing to maintain accurate financial records, and failing to file prompt financial reports with the SEC, In addition, the federal agency charged Rognlien with violating the insider trading provisions of the federal securities laws.As a result of these findings, the SEC imposed permanent injunctions on each of the three individuals that prohibit them from engaging in future violations of federal securities laws. The SEC also attempted to recover from Rognlien the $237,000 he received from selling the 100,000 shares of Cardillo stock in April 1986 . In January 1989, the two parties resolved this matter when Rognlien agreed to pay the Sec $60,000

Immigration to the United States and Dream Act

Immigration Immigration policies and immigrants was a major issue in the American Society. The Immigration Act of 1990 raised the amount of immigrants that were allowed in the United States. Each year the number of immigrants that come to the United States were known to be very skillful and talented workers. They could have improved the American Society. Immigrants often traveled with their families. Many of the Immigrants that came to the United States came for a better life and to have more opportunities.The Immigration Act of 1990 also allowed no limit on the amount of visas that a family could have. Because of this 71 percent of immigration visas were going to residents. A law was also formed on how immigrants could get deported. The amout of deportations also increased as the years went on. People were concerned that the laws being passed gave immigration to much power. They get o make to much decisions. In 2012, the DREAM Act was created. It was created based upon immigrants, e ducators, and business leaders.Many people were against the DREAM Act, many people were for it, and their were those who were between it. The DREAM Act was able legalize the undocumented minors that entered the country. The meaning of the DREAM Act is Development Relief and Education of Alien Minors. Their are several requirements that the DREAM Act has in order for a person to eligible for it. To be eligible for the DREAM Act a person must have been 15 years of age or younger when they entered the country. Proof must being given to show that they have been in the country for at least 5 years.Some form of education either a GED or a high school diploma must be shown. They must also be under the age of 30. All of this information can be shown in Document 1. Not many states allow undocumented immigrants to enter the country and receive an education, but New York is one of the few states that allow immigrants to receive an education. I am in favor of the DREAM Act because it has many o pen opportunities for undocumented immigrants. The main goal of the DREAM Act is to makesure that undocumented immigrants can vote, be sucessful, and be apart of the Union.The DREAM Act supports immigrants and wants them to make it somewhere in life and be able to adapt to the American culture. Immigration Policies and Immigrant Policies are discussed in Document 4. Document 4 is stating that the U. S immigration policy wants to keep the United States as a union, which means making undocumented immigrants apart of the United States. Document 4 also shows that the United States also wants to have different cultural mixes involving a variety of different people from different places.Having morals and values are important to immigrants and also the people who are apart of the United States. The current policy for undocumented immigrants is that they still have to go through an interrogation and other processes. Another goal of the DREAM Act is to make sure that everyone is covered with health insurance. As immigrants entered the country, it was possible for them to bring different diseases with them. In 2009, immigrants had more health insurance than the native-borns. About 87. 6 percent of the United States population had health insurance, and the other 14. 1% didn’t.Compared to immigrants the native-borns were no where near having that many people on health insurance, as shown in Document 12. As the years continued, the percentages of immigrants coming to America increased. Most of the undocumented immigrants settled more in the west. The foreign born population was taking over. This is shown in document 9a. Immigrants also took jobs from the Americans because they were more hard-working. Majority of the countries that immigrants came from involved hard labor, so they already knew what it was like to work. Eventually immigrants began to pay taxes.The immigrants who were paying taxes were the ones who were head of their households. Document 9b shows ten d ifferent states that had immigrants paying taxes. The immigrants who were paying taxes were the ones who were the head of their households. Document 9b shows ten different states that had immigrants who were paying taxes. California had the highest amount of taxes being paid. While Washington and North Carolina had the lowest. Georgia, New Jersey, and Arizona are all at the same amount when it comes down to the taxes that are paid by undocumented immigrants who are the head of their households.Undocumented immigrants continue to come to the United states. The number of immigrants who are entering the country continues to increase. Immigrants are settling in the other states also. The DREAM Act applies to and affects immigrants who are entering the United States without any full understanding of how they are going to survive. Since the DREAM Act has been passed for mainly minor immigrants, it affects their level of learning. The DREAM Act requires having some learning experience and stable proof to show that. But depending on what country a inor is coming from the learning curriculum in the United States would be different from how it was to them in their home country. The DREAM Act also says that parents should start teaching their children from home so that when it’s time for them to attend public school they aren’t far behind, and maybe they will be able to pick up quickly. Overall, I still believe that the DREAM Act should be passed, but not in full because it does have a positive impact on our society and it also takes away some of the power that immigration has.

modlife essays

modlife essays Modern Day Lifestyle Road to Development or Detriment? Today mans kitty has almost everything that he could think about only a few years ago. He is the lord and master of all things and beings by way of his immense measure of control. His intellect and ingenuity have resulted in the creation of many wonders which one would only have regarded fantasy in those times. It is true that there is enough for man to feel proud about. He has conquered the forces of nature or alternatively has created a shield against them. He has fashioned artificial beings to come at his beck and call, easing out the labour that he had to put in initially. He has gadgets and gizmos to expedite all processes. Man has even figured out drugs and remedies for curing the ailments that would claim large number of lives earlier. In all this, the life seems to be moving at an extremely fast pace that has in fact become too fast for him to match up with also. All things come at a price, literally and figuratively. First his aspirations make him strive hard to get the possessions of comfort. There are long hours at work, tired mind and bodies. Later on acquisition, the lifestyle becomes unhealthy with a dependence pattern setting in. Are all the modern day comforts adding to our problems? Is the purpose of convenience defeating the end of healthy living? Miss. A I do not think that the kind of life that we are leading today is causing any harm. It is in a persons own hands to be healthy or unhealthy. He can easily crumble in the face of pressure and give in to unhealthy habits or be conscious about it. It is easy to criticize the harmful facets of anything. But we must not forget to be grateful for the number of comforts that we have at our disposal today. We do not face any of the hardships that the generations before us used to face. The advancements in the field of science and technology have enabled us to tackle life more easily. Fo...

Organ Donation is a means of showing love Essays

Organ Donation is a means of showing love Essays Organ Donation is a means of showing love Paper Organ Donation is a means of showing love Paper Nowadays, healthcare practitioner’s especially in nursing faces lots of ethical issues and they will still be facing in the future and the more when the technology is getting more developed. One of which is the Organ Transplantations. Organ Transplantation is very rampant especially in countries with rising technologies in health care. If a certain family needs the organ but does not win in the bidding being done, then they would not get the organ We can not deny that Organ Donation is a means of showing love and concern to others. It gives a good reputation to the individual, especially when he dies because he has helped someone or has supported someone else’s life. But sometimes, the real meaning of giving motivated by love is already out of the context. For people, because of lack of finances gambles to donate a part or an organ. Nurses in this case, have a lot of moral issues to face with.   As a healthcare practitioner they have the duty to take care and preserve human life and dignity. That is, the body we have, is entrusted to us by God and therefore we should not let it be sold. To treat human body parts as commodities violates the Human Dignity. Even if the motive is to help others, the end still just not justifies the means of doing it. Human life is sacred and must be taken care of. As health workers they are face with different changes in the delivery of health care services to the society. In this situation, the nurses are in between the Philosophy which God has established in His word and the uprising technology in their fields. They are much affected with it because as nurses, it is their vows and promise to preserve the human life but organ transplantations as understand by some is just totally deviating from God’s perspective and in His view in giving. Some individuals would make it just a business. Yes, their reason might be is to help but underneath it is the idea of making large amounts of money. Nurses, on the other hand do their part in talking to families who have just lost someone about transplantation. A health care giver also needs to be educated in a proper way about what organ donation is really all about. It is the nurses’ job to talk and approach donors and their families regarding the organ transplantation. They should show the love and support that the family needs. Whatever reasoning is being done still it violates God’s laws. It does not respect the human lives. Nurses are compromising the Sanctity of Human Life. Nurses are sandwiched in the perspective of the rising technology of this world and Heavenly laws. Many ethicists find it so immoral to sell an organ because for them, God gave it to you and He entrusted it to you and for you. Therefore, as stewards we should do anything that could break the real purpose of God in us. Hence, as nurses they have a great responsibility. So they should do things to educate the individuals in the society about the process. They should explain that organ transplantation is not merely harvesting a person’s organs but it has a deeper purpose, a deeper meaning. They should show respect in the patient’s body so as not to deviate from the norms and prevent ethicists from arising and in throwing issues that health care providers are much affected of. Reference: Transplantation. New Standard Encyclopedia.   Page 363. Volume 17.

7 Steps for Writing a Paper on an Environmental Issue

7 Steps for Writing a Paper on an Environmental Issue Are you a student tasked with writing a research paper on an environmental issue? These few tips, along with some hard and focused work, should get you most of the way there. 1. Find a topic Look for a topic that speaks to you, that grabs your attention. Alternatively, choose a topic about which you are genuinely interested in learning more. It will be a lot easier to spend time working on something of interest to you. Here are some places you can find ideas for a paper: Of course, here on About.com’s Environmental Issues site. Browse the front page to see if a topic grabs your attention, or go to more specific content hubs like these ones:Global warmingBiodiversityDeforestationFossil fuelsWater PollutionThe science or environment sections of major newspapers and news organizations will feature articles about current environmental news and events.Environmental news websites like Grist or Environmental News Network. 2. Conduct research Are you using internet resources? Make sure you can assess the quality of the information you find. This article from Purdue University’s Online Writing Lab is useful to help with assessing the quality of your sources. Print resources are not to be neglected. Visit your school or city library, learn how to use their search engine, and talk to your librarian about accessing the resources available. Are you expected to constrain your sources to primary literature? That body of knowledge consists of peer-reviewed articles published in scientific journals. Consult your librarian for help with accessing the proper databases to reach those articles. 3. Follow instructions Carefully read the handout or prompt given to you and which contains instructions about the assignment. Early in the process, make sure you choose a topic that will satisfy the assigned requirements. Once half-way through the paper, and once when it’s done, check it against the instructions to make sure you didn’t drift away from what was required. 4. Start with a solid structure First craft a paper outline with your main ideas organized, and a thesis statement. A logical outline will make it easy to gradually flesh out ideas and eventually produce complete paragraphs with good transitions between them. Make sure all the sections serve the purpose of the paper outlined in the thesis statement. 5. Edit After you have a good draft produced, put the paper down, and don’t pick it up until the next day. It’s due tomorrow? Next time, start working on it earlier. This break will help you with the editing stage: you need fresh eyes to read, and re-read your draft for flow, typos, and a myriad other little problems. 6. Pay attention to formatting Along the way, check that you are following your teacher’s formatting instructions: font size, line spacing, margins, length, page numbers, title page, etc. A poorly formatted paper will suggest to your teacher that not only the form, but the content is of low quality as well. 7. Avoid plagiarism First, make sure you know what plagiarism is, you can then more easily avoid it. Pay especially close attention to properly attributing the work you cite. For More Information Purdue University Online Writing Lab. Writing a Research Paper.

Career paper Essay Example | Topics and Well Written Essays - 500 words

Career paper - Essay Example ic installations, preparing the software and testing it for the processing of documents, distribution of software, planning and scheduling of the project milestones for timely delivery of the project, software troubleshooting, determination of the time for management escalation, being up-to-date on the latest enhancements made to the software. The Systems Consultant may be required to provide support on call in the off hours. They also carry out on-site field testing as well as analysis of results at the facilities of the client. Growth opportunities for an individual with a degree in Information Systems are plentiful in the present age. From the year 2010 to the year 2020, the projected growth in employment by 18 per cent is faster than average whereas the average salary of an Information Systems Technologist ranges up to $52,000 that is also above average (Diploma Guide, 2013). Skills required of a Systems Consultant include experience with integrated 3rd party applications, hardware, and operating systems. Experience in providing technical implementations may also be very useful for the entry-level

Course Pak Articles Spring 2013 Term Paper Example | Topics and Well Written Essays - 2000 words

Course Pak Articles Spring 2013 - Term Paper Example This holding environment is of great importance for lesbians in the society in the sense that it acts as a therapeutic holding environment. In this environment, a lot of healing and progress takes place and hence it acts as a safe psychological place for therapy. In these holding environments, deep connections are established where unconscious communication can be established. This is as determined by scharff and scharff in the year 1991(Sussal, (n.d). In the social context, the approach used by the author in couple’s therapy is with psychoanalytical approaches. In the psychoanalytical approaches, stresses affecting the lesbian couples are addressed with regard to their past and the present. This approach is effective in the sense that the problems facing the lesbian couples are addressed at their roots and hence workable solutions are determined. The use of the psychoanalytical approach to couples therapy is effective to the lesbian couples because lesbian couples are more likely to be exposed to social discriminations as they go about their lives. Hence, this form of therapy according to the author is effective in curing cases of homophobia among lesbians, which is considered a sickness (Sussal, (n.d). Couple’s therapy with lesbians employs the use of repressed ego systems. The use of repressed ego systems has improved the relations between lesbian couples. This is because it assists couples in overcoming the fears intimacy because of experiences of rejection and frustration. Fairburn determined this theory in the year 1954 in what was known as anti-libidinal ego. This theory determined that split off ego is resident in the unconscious and affects how lesbians relate to each other as a couple and towards the outside world (Sussal, (n.d). Sex therapy is inclusive as part of couple’s therapy with lesbians. This is because just as is the case with heterosexuals, lesbians have their share of

Defining Love Essay Example | Topics and Well Written Essays - 500 words

Defining Love - Essay Example The word "love" has origin in the English language. Lufu in the Old English was related to the Frisian luve, German luba, and Gothic lubo. The Scandinavians have used the word lof and Latin lubet. In the form we have now "love" was recorded from the English writings in the 8th century (Frequently Ask Questions). Each nation gives a different name to love, but the essence remains the same. What exactly is love Love is a feeling, it would be more appropriate to say, a combination of positive feelings and emotions that make a person happy. Plato has noted that "at the touch of love everybody becomes a poet" (Famous Love Quotes). When people are in love the world seems to be more colorful, pleasant place to live, the person in love is smiling and does not pay attention to the problems and negative moments. Plato has introduced the concept of platonic love meaning that two individuals, a man and a woman, being in love should get emotionally and spiritually close, without sexual relations. He believed that sex can destroy the emotional unity. Platonic love is different from love based on passion when lovers seek not only emotional but also physical unity with each other.

China as a super power Term Paper Example | Topics and Well Written Essays - 1500 words

China as a super power - Term Paper Example On March 4, 2007, China announced that it was going to increase its military to a total of 45 billion dollars (Tkacik, 2007). This was the biggest annual increase in China’s military budget; however, China was quick to reassure the world that there was no need to worry by calling the increment normal. A further look into this increment indicated that China has an intention to challenge the United States’ military supremacy. This could lead to a situation where China is the United States’ single competitor with regard to influence and military supremacy. China’s air force and space activity is on the rise. The army in China has got roughly 300 Russian fourth generation flankers; it has also got several homemade Jian-11 planes and 76 Sukhoi multi-role fighter jets. Russia and Israel assisted the Chinese air force in procuring 50 Jian-10 fighter jets. These jets were based on the United States F-16 technology. China has intentions to build more of these plane s. China has increased its production and deployment of the short-range ballistic missiles which are said to be aimed at Taiwan. This production has grown from 50 per year in 1990s to 150 missiles annually today. The industries that produce such missiles in China are said to grow at the same pace. In general, China’s rocket soldiers and its air force are expanding at an unprecedented pace. According to China’s 2006 White Paper, there is evidence that China is moving to offensive. This military might of China is growing from regional to trans-regional mobility. The air to ground military capacity has also grown, including long distance maneuvers and exceptional operations. The Chinese navy has grown in strength into a force that can operate in the maritime operations and can ably handle nuclear counterattacks. The Chinese air force has continued to increase its capabilities to strike, tried to procure air and missile defense shield systems and is looking into more offen sive and defensive operations. All these are an early warning shot of the Chinese reconnaissance. According to a report by Congress, China’s policy is now global and extremely bold. China has always been underrated and many times the United States said that China has not acquired the status of a super power. Thomas Jefferson, at the beginning of the nineteenth century, observed that the United States had to trade all over the world if it had to become a global power economically. Beijing’s assessment is that it has grown to the extent that its economic growth depends on foreign markets. This also includes the natural resources from other countries around the world. China‘s economy has been growing rapidly, and China is seeking military might that can protect this growth. This is similar to Jefferson’s observation that the United Stated had to build its military strength if it was to safeguard its military strength globally. It seems that the rise of the Pe ople’s Republic of China is both legitimate and inevitable (McLean, 2007). However, according to Condoleezza Rice, the former Secretary of State of the United States, the US needs to help China operate within the international rules framework before it has fully acquires the status of a military super power. Many view the rise of China as an exceedingly dangerous happening. Why does Bleicher think the fears are overblown? According to Samuel Bleicher, the idea that China is an emerging super power is a creation of the media. He believes s that

Meditation for chronic pain backed by nursing research Paper

Meditation for chronic pain backed by nursing - Research Paper Example In this regard, the current discourse aims to determine what nursing research says about using meditation to manage chronic pain; and, according to the role of nursing, one seeks to determine if this modality is effective in treating chronic pain. Nursing Research on Meditation to Manage Chronic Pain The research article written by Chiesa and Serretti (2011) and entitled â€Å"Mindfulness-Based Interventions for Chronic Pain: A Systematic Review of the Evidence† proffered pertinent issues relative to using mindfulness-based interventions (MBIs) and mindfulness-based stress reduction (MBSR) techniques to alleviate chronic pain. As disclosed, â€Å"MBSR is a standardized group-based meditation program conceived in the late 1970s from the effort to integrate Buddhist mindfulness meditation with contemporary Western clinical and psychological practice† (Chiesa & Serretti, 2011, p. 83). The authors initially described techniques commonly applied in MBSR that focuses on body scan, sitting meditation, and yoga (Chiesa & Serretti, 2011). The findings revealed inconclusive evidence regarding the effectiveness of using MBIs as an intervention for chronic pain and to allegedly reduce related depression that ensues from the pain experience. In another study written by Morone, Lynch, Greco, Tindle, and Weiner (2008), the authors sought the participation of 27 older adults reportedly complaining of low back chronic pain. Through the use of mindfulness-based stress reduction (MBSR), in conjunction with diverse methods that aim to reduce pain, such as â€Å"distraction, increased body awareness leading to behavior change, better pain coping, and direct pain reduction through meditation† (Morone, Lynch, Greco, Tindle, & Weiner, 2008, p. 841), participants have noted in their respective diaries, significant improvement in managing pain, in well-being, in sleeping, and in attention-related activities. Finally, in the study conducted by Tul, Unruh, and Dick (2 011), the authors specifically aimed to determine how yoga, a form of meditation, serves as a means to address chronic pain. As specifically revealed, â€Å"the yoga program offered its participants a new way of engaging with their body resulting in heightened re?ection and self-awareness that enabled most participants to feel more control over their pain† (Tul, Unruh, & Dick, 2011, p. 440). As such, the meditative strategy accorded through yoga enabled the participants to refocus on more positive methods for relaxation that allowed them to channel their energies to meditation techniques rather than be fixated in the chronic pain. The research article written by Chiesa and Serretti (2011) actually included, through a tabular representation, the summary of previous studies conducted on the subject of using meditation as a means to alleviate chronic pain. The summary disclosed that 10 conclusive studies had focused on MBIs but generated different results, as above noted. As cle arly founded, â€Å"there is not yet suf?cient evidence to determine whether MBIs could be more ef?cacious than nonspeci?c interventions such as support and educational control groups for the reduction of pain and depressive symptoms in patients with chronic pain† (Chiesa & Serretti, 2011, p. 91). Meditation as Modality to Treat Chronic Pain As Seen through the Role of Nursing From the diverse results that were disclosed and which

The Devil Wears Prada Media Analysis Movie Review

The Devil Wears Prada Media Analysis - Movie Review Example Andrea knows nothing about fashion and people at the magazine makes fun of her. Throughout the film, her sense of style changes and she becomes a true fashionista. But as everything comes with a price, her relationships with friends and boyfriend starts falling apart. At the end of the movie, Andy understands that life is made of hard choices and she needs to go after what she wants. This movie represents the fashion industry as a world full of narcissistic and shallow people. An example is the way that everyone at Runway Magazine starts treating Andy differently when she decides to dress â€Å"accordingly†. She became respected by Emily, the first Assistant, and only after the makeover that she started to get thinks right that Miranda asked her. The fact is that the movie emphasizes the change of her behavior on the fact that she gave in into the fashion world, but the truth is that she changed her perspective and decided to have a positive attitude towards the things she needed to do. To create this high fashion atmosphere, the use of costuming is indispensable. As Stutesman would argue, â€Å"[costume] must express something far beyond the outfit: the costume designer must use clothes to create basic movie elements† (Stutesman 20). If the right clothes were not used, then the movie would not make as much sense, or it would not make the same impact as it did when it first came out.

Meditation for chronic pain backed by nursing research Paper

Meditation for chronic pain backed by nursing - Research Paper Example In this regard, the current discourse aims to determine what nursing research says about using meditation to manage chronic pain; and, according to the role of nursing, one seeks to determine if this modality is effective in treating chronic pain. Nursing Research on Meditation to Manage Chronic Pain The research article written by Chiesa and Serretti (2011) and entitled â€Å"Mindfulness-Based Interventions for Chronic Pain: A Systematic Review of the Evidence† proffered pertinent issues relative to using mindfulness-based interventions (MBIs) and mindfulness-based stress reduction (MBSR) techniques to alleviate chronic pain. As disclosed, â€Å"MBSR is a standardized group-based meditation program conceived in the late 1970s from the effort to integrate Buddhist mindfulness meditation with contemporary Western clinical and psychological practice† (Chiesa & Serretti, 2011, p. 83). The authors initially described techniques commonly applied in MBSR that focuses on body scan, sitting meditation, and yoga (Chiesa & Serretti, 2011). The findings revealed inconclusive evidence regarding the effectiveness of using MBIs as an intervention for chronic pain and to allegedly reduce related depression that ensues from the pain experience. In another study written by Morone, Lynch, Greco, Tindle, and Weiner (2008), the authors sought the participation of 27 older adults reportedly complaining of low back chronic pain. Through the use of mindfulness-based stress reduction (MBSR), in conjunction with diverse methods that aim to reduce pain, such as â€Å"distraction, increased body awareness leading to behavior change, better pain coping, and direct pain reduction through meditation† (Morone, Lynch, Greco, Tindle, & Weiner, 2008, p. 841), participants have noted in their respective diaries, significant improvement in managing pain, in well-being, in sleeping, and in attention-related activities. Finally, in the study conducted by Tul, Unruh, and Dick (2 011), the authors specifically aimed to determine how yoga, a form of meditation, serves as a means to address chronic pain. As specifically revealed, â€Å"the yoga program offered its participants a new way of engaging with their body resulting in heightened re?ection and self-awareness that enabled most participants to feel more control over their pain† (Tul, Unruh, & Dick, 2011, p. 440). As such, the meditative strategy accorded through yoga enabled the participants to refocus on more positive methods for relaxation that allowed them to channel their energies to meditation techniques rather than be fixated in the chronic pain. The research article written by Chiesa and Serretti (2011) actually included, through a tabular representation, the summary of previous studies conducted on the subject of using meditation as a means to alleviate chronic pain. The summary disclosed that 10 conclusive studies had focused on MBIs but generated different results, as above noted. As cle arly founded, â€Å"there is not yet suf?cient evidence to determine whether MBIs could be more ef?cacious than nonspeci?c interventions such as support and educational control groups for the reduction of pain and depressive symptoms in patients with chronic pain† (Chiesa & Serretti, 2011, p. 91). Meditation as Modality to Treat Chronic Pain As Seen through the Role of Nursing From the diverse results that were disclosed and which

Business Writing Coursework Example | Topics and Well Written Essays - 500 words

Business Writing - Coursework Example Business writing should be equipped with strong ideas that will constitute its main theme; ideas which can exploit the concept of social validation in the society and appeal to the reader. This will render the reader’s mind with the positive image of the addressed product, service or idea. Strong ideas will primarily focus on the magnitude of profit the client or end user will gain after buying the product about which the business writing is talking about. The potent and strong ideas at the start of the business writing will lay a durable and robust image in the reader’s mind that will get the attention and attract him. The style of writing will be alluring and enticing so that the reader can enjoy the writing as well as perceive it to be of his utility otherwise the reader will not bother to waste his time in any useless piece of paper. The business writing should also be logically organized and ordinal factor must be inculcated at every sentence. No word or sentence should be written without the reason and intent. The writer must ensure the smart deployment of the paragraphs and size factor. Similarly, the composition and categorization of paper must be sensible enough to manifest and parade a professional image to the reader. For example, the writing should give an introduction then explanation of the subject matter and then a short conclusion summarizing the intent and finding of the business writing. The structural dynamics of the business writing should be set according to the target audience but the common practice of good business writing is to follow the AIDA methodology which means; The choice of words is of grave importance in business writing because words make the composition and structure of the paper.

Lesson Plan in Classroom Program Essay Example for Free

Lesson Plan in Classroom Program Essay In our modern epoch, the time when the only things that are needed for effective learning are the teachers and students is long gone. At the turn of the millennium, the equation to successful teaching also has the variables of classroom schedule, room assignment and even proper assignment of teachers. Although these factors may seem insignificant, all of those can be the telling elements as to whether the highest possible level of edification is attained. During our first teaching episode in our cooperating school, Tagum City National Comprehensive High School, I quickly took notice about the schedule of our CT. Mam Mercado’s schedule is obviously loaded, with only a few minutes of break or rest in between. Her class schedule as well as room assignment was relatively reasonable (in the Philippines’s educational setting). As she is assigned to teach English which is her major, it can be concluded that her students will acquire adequate learning. All these factors greatly contribute to the effectiveness of teaching as well as learning. Having stated that, I realized that for a lesson or a curriculum will be best implemented and taught if all the necessary components, which in this case are the class program, teacher’s assignment and room assignment, are present and well organized. Proper organization can greatly influence and even pad up the interest and enthusiasm of the students. On the part of the teacher, it eases up the tasks to be done knowing that most of these portions which he/she can’t control are put right in place. With that considered, the educational institution can be confident that the zenith of the teaching-leaning process is achieved. Due to some obvious reasons, we were not able to interview our CT about her Class Program. However, she shared to us how important it is to prepare a class program and implement it adaptably. With that, both the teacher and  the learners will know what to do expect as well as do next. With all that has been learned, I realized that there are many dynamics to be considered before effective edification can be professed. Most importantly, proper preparation and implementation of the class program should be given due concern for it can immensely affect learning.

Flow Cytometry for the Evaluation of Semen

Flow Cytometry for the Evaluation of Semen State of the Art in Sperm Assessment Using Flow Cytometry Abstract Flow cytometry is emerging as a substantial tool in the domain of modern andrology for the routine analysis of spermatozoa. Recent application of flow cytometry in the artificial insemination industry especially for pig is a new approach. Until very recent, analysis of semen samples was routinely performed by microscopical evaluation and manual techniques by laboratory operators; analysis is inclined due to comprehensive variability among observers, influencing its clinical validity. During last decade, to evaluate farm animal semen, variety of new flow cytometric techniques have been intercalated which made possible a wide spread evaluation of several sperm functionality and characteristics. Here in this paper, an initiative has been taken to explore numerous current flow cytometry developments pressing for andrological tests. After the invention of flow cytometry, sperm evaluation by traditional (microscopic) means became questioned and avoided due to the robust advantages of flow cytometry over the microscopic methods. By the recent development of diverse fluroscence probes, flow cytometry became capable of analyzing number of sperm characteristics like viability, capacitation, acrosomal integrity, membrane permeability, membrane integrity, mitochondrial status, DNA integrity, decondensation of DNA and differences between gametes based on sex. The application of flow cytometry to their detection allows increased numbers of spermatozoa to be assessed over a short time-period, provides the opportunity of working with small sample sizes, increases the repeatability of data obtained, removes the subjectivity of evaluation and allows simultaneous assessment of multiple fluorochromes. Thus, flow cytometry is a technique capable of generating significantly novel data and allows the design and execution of exper iments that are not yet possible with any other technique. Nowadays, semen evaluation using laboratory analyses is very meaningful to the artificial insemination industry to provide the most desired quality product to customers. Future development of flow cytometric techniques will permit further advances both in our knowledge and in the improvement of assisted reproduction techniques. In this paper, the main semen attributes that can be analyzed with fluorochromes and adapted for use with a flow cytometer will be reviewed and the relationship of these tests to fertility will be discussed. Introduction Up to now, semen evaluation is considered as the most important laboratory test that has enabled us to identify and predict clear-cut cases of fertility (Jarow et al., 2002), infertility or even of potential sub-fertility (Rodrà ­guez-Martà ­nez, 2007). Determination of the potential fertility of semen sample and, in the long run, of the male from which it has been collected is the ultimate goal of semen evaluations in clinically healthy sires. Now a days, many methods for the estimate the possible fertilizing capacity of a semen sample and, or in the word, of the male (reviewed by Dziuk 1996; Rodrà ­guez-Martà ­nez et al. 1997a; Rodrà ­guez-Martà ­nez and Larsson 1998; Saacke et al. 1998; Larsson and Rodrà ­guez-Martà ­nez 2000; Rodrà ­guez- Martà ­nez 2000, 2003; Popwell and Flowers 2004; Graham and Mocà © 2005; Gillan et al. 2005) are existing. The methods routinely accustomed for evaluation of the quality of a semen sample involved an evaluation of general appearance, volume, pH, sperm concentration, viability, morphology and motility. Most of these evaluations are based on microscopic analyses that only measure relatively a few numbers of spermatozoa within a population. In most of the cases, these are time-consuming; results obtained are controversial and are not translatable. It should also be noted that such conventional techniques are apt to extreme inter-ejaculate variation, even when the laboratory methodology has been standardized. In the wake of this information, new opportunities have arisen for the development of methods for the diagnosis of male infertility, many of which have been shown to exhibit a prognostic value that eludes conventional semen profiling. Moreover, ejaculated spermatozoa are nowadays handled for use in assisted reproductive technologies, such as the artificial insemination of chilled, frozen-thawed or sexed semen, and IVF. During this long processes, number of steps like semen extension, fluorophore loading, ultrav iolet and laser illumination, high-speed sorting, cooling and cryopreservation are followed, which create a scope to impose different degrees of change in sperm functionality followed by suffer of damage to sperm membranes, organelles or the DNA content. Therefore, although several assays have been developed to monitor these sperm parameters, recently it is being claimed by many groups that buck of those so-called procedures are incomplete, time consuming and laborious. Flow cytometry in diverse technical applications proposes many advantages for the analysis of sperm quality. Flow cytometry is a method where multiple fluorescences and light scattering can be induced allowing single cell or particles illumination in suspension while they flow very rapidly through a sensing area. The increasing use over the past decade of flow cytometry in the leading laboratories in human and veterinary andrology has dramatically increased our knowledge of sperm function under physiological and biotechnological conditions. Flow cytometers is capable to acquire data from several subpopulations within a sample in a few minutes, making it perfect for assessing heterogenous populations in a semen sample. Flow cytometry was initially developed in the 1960s, after that flow cytometry is performing automated separation of cells based on the unique recognition of cellular patterns in a population feasible (Hulett et al., 1969). Likewise, cellular patterns can be recognized by utilizing such a separation approach, in each cells within a population (Baumgarth and Roederer, 2000; Herzenberg et al., 2006). The first notion of flow cytometry development was for medical and clinical applications such as haematology and oncology. Although still much research is going on these medical areas and account for the vast majority of publications on this robust technique, but during the past few years it is being used in a diverse areas, such as bioprocess monitoring, pharmacology, toxicology, environmental sciences, bacteriology and virology. Together with elevated use in many areas, recent advancement of flow cytometry increased its application in the reproductive biology especially for andrology. Although flow cytometry may overestimate the population of unlabelled cells (Petrunkina and Harrison, 2009), plethora of research from our group in pig (Pena et al., 2003, 2004, 2005; Spjuth et al., 2007; Fernando et al., 2003; Saravia et al.,2005, 2007,2009; De Ambrogi et al., 2006; ) bull (Bergquist et al., 2007; Nagy et al., 2004; Januskauskas et al., 2003; Bergqvist et al., 2007; Hallap et al., 20 05, 2006;) stallion ( Kavak et al., 2003; Morrell et al., 2008) indicate that newly developed fluorescent stains and techniques of flow cytometry has made possible a more widespread analysis of semen quality at a biochemical, ultrastructural and functional level. Therefore, flow cytometry is the current technical solution for rapid, precisely reproducible assessment of sperm suspensions. In this review we have described potentiality and scope of flow cytometry for the evaluation of semen, and the way in which this technique can be used in clinical applications for andrology based on some of our previous experiences. Definition of flow cytometry The definition of a flow cytometer is ‘an instrument which measures the properties of cells in a flowing stream or ‘an instrument that can measure physical, as well as multi-colour fluorescence properties of cells flowing in a stream. In other word, cytometry is a method which measure physical and chemical attributes of cells or other particles. Such a measurement is made when cells or other particles pass in single file through some sort of measuring apparatus in a stream of fluid. The data obtained can be used to understand and monitor biological processes and develop new methods and strategies for cell detection and quantification. Compared to other traditional analytical tools, where a single value for each attribute is obtained for the whole population, flow cytometry provides data for each and every particle detected. As cells differ in their metabolic or physiological states, flow cytometry allows us not only to detect a particular cell type but also to find different subpopulations according to their structural or physiological parameters. Flow cytometry is a technique for measuring components (cells) and the properties of individual cells in liquid suspension. In essence, suspended cells are brought to a detector, one by one, by means of a flow channel. Fluidic devices under laminar flow define the trajectories and velocities that cells traverse across the detector, and fluorescence, absorbance, and light scattering are among the cell properties that can be detected. Flow sorting allows individual cells to be sorted on the basis of their measured properties, and one to three or more global properties of the cell can be measured. Flow cytometers and cell sorters make use of one or more excitation sources and one or two fluorescent dyes to measure and characterize several thousands of cells per second. Flow cytometry presents objective and precise results (Bunthof et al., 2001; Shleeva et al., 2002), which help to overcome the problems with the manual methods described above. Function and types of flow cytometry A flow cytometer is made of three main systems, fluidics, optics and electronics. ItI It can acquire data on all subpopulations within a sample, making it ideal for assessment of heterogenous population, such as spermatozoa. The adaptation of flow cytometry to sperm assessment came in to function when it was used for measuring their DNA content (Evenson et al., 1980) and its application for analyzing semen has been increased rapidly in last decade. Flow cytometry is now applied for the evaluation semen such as sperm viability, acrosomal integrity, mitochondrial function, capacitation status, membrane fluidity, DNA status and so on. Continuous innovation of new fluorescent stains and techniques facilitated the flow cytometric evaluation of spermatozoa. Flow cytometry allows the observation of physical characteristics, such as cell size, shape and internal complexity, and any component or function of the spermatozoon that can be detected by a fluorochrome or fluorescently labeled compound. The analysis is objective, has a high level of experimental repeatability and has the advantage of being able to work with small sample sizes. Flow cytometry also has the capacity to detect labeling by multiple fluorochromes associated with individual spermatozoa, meaning that more than one sperm attribute can be assessed simultaneously. This feature has an added benefit for semen analysis, as few single sperm parameters show significant correlation with fertility in vivo for semen within the acceptable range of normality (Larsson and Rodriguez-Martinez, 2000) and it is the general statistics that the more sperm parameters can be tested, the more accurate the fertility prediction becomes (Amman and Hammerstedt, 1993). There are two main types of flow cytometers-analysers and sorters are in use. Together with data collection on cells, sorters have the potentiality to sort cells with particular properties (defined by the flow cytometer operator) to extremely high purities. There are also a number of commercial flow cytometers that have been developed for particular analytical requirements. Partec manufacture a Ploidy Analyser and also a Cell Counter Analyser. Optoflow has developed a flow cytometer for the rapid detection, characterization and enumeration of microorganisms. Luminex is developing technology for multiplexed analyte quantitation using a combination of microspheres, flow cytometry and high speed digital processing. Advantages of FC compared to other conventional techniques to explore sperm structure and function Use of authentic assays in the fertility clinic and artificial insemination industries increasing day by day. In this respect, use of flow cytometry might be an important attempt to resolve sustaining problem with so called commonly used manual method for the semen analysis. An additional source of laboratory variation is the low number of sperms analyzed with such techniques. It is worth mentinign here that so called method deal only with few hundred sperm. When we deal with such a few sperm population, there is a possibility that obtained result might not be statistically significant (Russel and Curtis, 1993). The methods which are frequently used are enable to determine sperm concentration (Jorgensen et al., 1997), motility or morphology only (Keel et al., 2002). Objectivity, cell number measured, speed of count and precision are the advantages of flow cytometry to conventional light microscopy techniques (Spano and Evenson, 1993). The technique now a days has been used to determi ne a number of factors including those of acrosome status, membrane integrity, mitochondrial function as well as multiparameter measurement in human (Garrido et al., 2002). Flow cytometry has the ability to analyze thousands of cells in few minutes. In our series of studies, we demonstrated the feasibility and reproducibility of an automated method to evaluate sperm cell type, count, and viability in human boar samples. In our hand, the precision of the flow cytometric analysis is satisfactory in a diverse species (boar, bull, stallion etc), and the observed errors were significantly better than those obtained from the so-called manual methods. Although there are diverse benefits of flow cytometer for the analysis of semen, feasibility of applying flow cytometry sometimes restricted to researcher due to the high outlay and difficulties of operation associated with the requirement of a skilled operator. Further, a flow cytometer is very large and cannot resist shocks associated with movement, and it also requires much space in the laboratory. Whatever may be the limitation, the development of more affordable ‘‘bench-top flow cytometers in recent time raised the potential essentialities to semen analysis. If the further application of flow cytometric analysis is considered further, it might be seen that it is growing popularities as a technique for assessing more than one sperm attribute, simultaneously. Compared to traditional microscopic techniques, flow cytometry analysis is allowing to give a far more simplified and objective method of semen analysis, especially in relation to fertilization with acrosome reactivity potential of spermatozoa (Uhler et al., 1993; Purvis et al., 1990; Carver-Ward et al., 1996). A large number of different techniques to estimate sperm concentration have been reported. In the mid-1990s a series of fixed-depth disposable slides were evaluated as rapid and effective pieces of equipment for the estimate of sperm concentration. Data from a number of preliminary studies proposed that, at least in the 20-mm-depth format, such chambers resulted in a noticeable underestimate of sperm concentration compared to the gold standard (improved Neubauer hemocytometer). According to the World Health Organization that ‘‘such chambers, whilst convenient in that they can be used without dilution of the specimen, might lead to inaccuracy (World Health Organization, 1999). Data from Tomlinson and colleagues indicate that two proprietary disposable slides (Microcell, Conception Technologies, San Diego, Calif; Leja, Leja Products, BV Nieuw- Vennep, The Netherlands) can result in a lower concentrations of sperm compared to the hemocytometer method (Tomlinson et al., 2001) . In contrast, plenty of reports document unacceptable differences between different laboratories and even between different individuals, although fewer studies attempt to address these issues. So, what is wrong? Improvement of semen quality testing has been emphasizing in some reports (Jorgensen et al., 1997; Keel et al., 2000). But due to low number of sperm evaluation by the conventional method results in poor reproducibility. These problems might be overcome when using flow cytometry. The validation of method is a challenge due to its essentiality of having specific, precise, objective, and accurate evaluation to establish a correlation of fertility data or to predict potential of a semen sample accurately (Amann, 1989). In a fertility clinic, precision of data in important as the result of semen analysis is frequently used to manage fertility of a patient and treatment of the unfertile couples. Thus, it is important to take into consideration within and between laboratory variations for successful infertility treatments. Sometimes its a matter of argument that compared to flow cytometry, fluorescent microscopy evaluate â€Å"patterns of fluorescence rather than the fluorescence intensity. Flow cytometer has the lack of ability to discriminate sperm containing a fluorescent marker bound to the equatorial segment or over one of the acrosomal membranes (Parinaud et al., 1993; Mortimer and Camenzind, 1989; Mortimer et al., 1987). Tao et al. (1993) compared flow cytometry and epifluorescent microscopy with various lectins and indicated that there is almost no difference between methodologies for detection of the acrosome reaction. However, it has been argued that lectins do not bind specifically to the acrosomal region of the sperm (Purvis et al., 1990; Holden and Trounson, 1991) and that other binding sites can be easily distinguished by epifluorescence microscopy, whereas flow cytometry identifies the signal from the entire sperm. Additionally, conventional light microscopic semen assessment is increasingly being replaced by fluorescent staining techniques, computer-assisted sperm analysis (CASA) systems, and flow cytometry (PenËÅ"a et al., 2001; Verstegen et al., 2002). Additional advantages over existing techniques are that this approach is faster than the hemacytometer and that cellular debris, fat droplets, and other particulate material in extended semen are not erroneously counted as sperm, as often occurs with electronic cell counters. This method can also be used to determine the number of somatic cells in a semen sample. Application of flow cytometry for sperm count Sperm count is an important predominant factor for the evaluation of sperm fertility potential. Accurate determination of sperm cell concentration is critical especially in AI industry because it provides assurance to customers that straws of extended semen contain the sperm numbers indicated which will help to decide appropriate doze especially for pig. Accuracy of sperm count is a common problem in the andrological laboratories and accurate measure of sperm concentration is particularly important for export in which verification of numbers may be required. Routine sperm counts can help to identify possible processing errors within a specific batch of semen or on a particular day, should those errors occur. As sperm counting procedures become more refined, routine counting can be used to monitor subtle changes in daily semen processing that might affect the number of sperm packaged in a straw. Every time new and more accurate methods for the sperm count determinations are coming and being replaced by the older ones. Some laboratories are trying the Maklerm counting chamber (Se if- Medical, Haifa, Israel) and other improved hemacytometers, such as the MicroCellTM (Fertility Technologies, Inc., Natick, MA); however, these techniques will likely have standard lems similar to those associated with the standard hemacytometers. Although hemacytometers are routinely used for sperm counts, due to the slow process and need for multiple measurements of each sample, the chance of error increase. Freund and Carol (ref) stated that a difference of 20% were not unusual between the determinations by the same technician. Electronic counters provide much more rapid counting, are easier to use, and give more repeatable results among technicians. However, those instruments tend to include in the sperm count any somatic cells present, immature sperm forms, cytoplasmic droplets, debris, and bacteria, thereby inflating the concentration value (Ref). Spectrophotometer is recently being used in the AI industries to assess sperm concentration by determining turbidity of a semen s ample using an instrument previously calibrated for sperm concentration with a hemacytometer or Coulter counter (Ref). The accuracy of this method depends on the methods used for spectrophotometer calibration. Although, sperm concentration can also be determined by spectrophotometrically, the debris present in the raw semen crease problem with misestimation. Sperm number in the frozen thawed semen is difficult to ascertain as most of the extender contain egg yolk particles, fats and other particles which affect measurement of sperm with electric cell counter or spectrophotometers (Evenson et al., 1993). On the other hand flow cytometry created possibilities of a rapid determination of sperm number in a precise form. It is the flow cytometry which can reduce intra-laboratory and inter-laboratory variation and conflict regarding sperm concentration assessment. Computer assisted semen analyzer is robust technique for analyzing sperm movement which can count sperm as well; but such an a nalyzer most of the cases use some counting chamber or hemacytometer which itself can generate error. Although, hemacytometer was originally developed for blood cell counting, its use is now diverse including andrological laboratories for sperm counting. Around two-decade ago flow cytometry was suggested for sperm numbers in straws of cryopreserved bull semen. Christensen et al. (-) observed similar results for sperm count with flow cytometry and hemocytometer for a number of species. Now a day a simultaneous determination of sperm viability and sperm concentration is possible which can avoid the chance of occurring differences between ejaculates leading lack of coordination with field fertility and laboratory analyses. Thus the present technology is more precise which can get rid of variation from handling the sperm sample and variation from pipetting and the analysis itself. Further, Prathalingam et al. (2006) concluded that there is similarities for sperm count result between flow cytometry and two newly approached method (image analysis and fluorescent plate reader) for sperm counting. Though, use of fluorescent plate was emphasized due to low cost and allowing large number of cells counting from a large number of ejaculates. Although flow cytometry has become a valuable instrument for andrological determinations, it is also blamed that sperm concentration by flow cytometry signify a higher value than the real one. The possibility arise might be due to that semen samples often contain some alien materials such as immature germ cells, epithelial cells, blood cells, cytoplasmic droplet, cellular debris etc. In the same way, frozen semen has higher chance to introduce such material as they contain diluents components especially egg yolk particles. These particles and cell debris might have frontal and side light scatter parameters those are similar to spermatozoa. Such sperm-count-overestimation problem arisen in our cases also, especially when we deal with frozen semen. Further it is also claimed that flow cytometry has a tendency to overestimate viable spermatozoa. We are also experienced with such trouble which we guess might be due to that egg particles of extender are considered as viable cell as for it s staining pattern. Our yet to publish data indicate that this problem can be mimic by a centrifugation process and by using low concentration sample for evaluation with flow cytometry. Very recently Petrunkina and Harrison (2009) proposed a mathematical equation for fixing this flow cytometric sperm counting. Thus much research is going on and we hope such discrepancy will completely be resolved near future to get advantage from this robust technology for sperm counting. Flow cytometry for detecting sperm intactness -Viability of spermatozoa The viability of spermatozoa is a key determinant of sperm quality and prerequisite for successful fertilization. Viability of spermatozoa can be assessed by numerous methods, but many are slow and poorly repeatable and subjectively assess only 100 to 200 spermatozoa per ejaculate. Merkies et al. (2000) compared different methods of viability evaluation. They concluded that Eosin-nigrosin overestimate viability while fluorescent microscope and flow cytometry estimate similar trend of viability. Current flow cytometric procedures are able to simultaneously evaluate sperm cell viability together with some other attributes. This method has been successfully used for assessing spermatozoa viability in men (Garner and Johnson, 1995), bulls (Garner et al., 1994; Thomas et al., 1998), boars (Rodrà ­guez-Martà ­nez, 2007; Garner and Johnson, 1995; Garner et al., 1996), rams (Garner and Johnson, 1995), rabbits (Garner and Johnson, 1995), mice (Garner and Johnson, 1995; Songsasen et al., 199 7), poultry and wildfowl (Donoghue et al., 1995; Blanco et al., 2000) and honey bees (Collins and Donoghue, 1999; Collins, 2000) and in fish (Martin Flajshans et al., 2004). Considerable information has accumulated on the use of fluorescent staining protocols for assessing sperm viability (Evenson et al., 1982). The SYBR 14 staining of nucleic acids, especially in the sperm head, was very bright in living sperm. Good agreement was observed between the fluorescent staining method and the standard eosin-nigrosine viability test; the flow cytometric method showed a precision level higher than that of the manual method. One of the first attempts to assess sperm viability utilized rhodamine 123 for determining potentiality of mitochondrial membrane while ethidium bromide for membrane integrity through flow cytometry (Garner et al., 1986). Other combinations that have been used to examine the functional capacity of sperm are carboxyfluorescein diacetate (CFDA) and propidium iodide (PI) (Garner et al., 1988; Watson et al., 1992); carboxydimethylfluorescein diacetate (CMFDA), R123, and PI (Ericsson et al., 1993; Thomas and Garner, 1994); and PI, pisum sativum agglutinin (PSA), and R123 (Graham et al., 1990). The most generally used sperm viability stain combinations is SYBR-14 and PI at present. This stains are now sold commercially as live/dead viability kit. When these two stains are combinely used, the nuclei of viable sperm take fluoresce green and membrane integrity lost cells take red stain. This staining technique has been used in a number of species, including the boar (Garner and Johnson, 1995; Saravia et al.,2005, 2007,2009). Although species differences do exist in the function of spermatozoa, the Live/Dead stain may similarly have no adverse affect on fertilization in the equine, although it remains to be tested in this species. Recently a new instrument (Nucelocounter-SP100) has been introduced to evaluate sperm concentration [11] and viability. Due to the small size and low cost, this instrument has been attracted for field measurements of both concentration and viability. In our hand this instrument was also became useful for the quick measurement of sperm concentration an d viability in stallion (Morrell et al., 2010). Fluorescent probes such as H33258, requiring flow cytometric analysis with a laser that operates in the ultraviolet light range, are less commonly used as this is not a standard feature on the smaller analytical machines. However, one alternative is to use a fluorometer. A fluorometer is a relatively low-cost piece of portable equipment that permits a rapid analysis to be carried out on a sample. Januskauskas et al. (2001) used H33258 to detect nonviable bull spermatozoa by fluorometry and obtained an inverse correlation between the damaged cells per cent and the field fertility. Another option is fluorescent attachments for computer-assisted semen analysis devices. For example, the IDENT fluorescence feature of the Hamilton-Thorne IVOS permits staining with H33258 allowing an assessment of sperm viability to be made along with motility. Fluorochromes used to assess sperm viability by both approach could be utilized in combination with each other. In that case, when CFDA is used combined with PI, three populations of cells as live, which are green; dead, which are red; and a third population which is stained with both and represents dying spermatozoa can be identified. This combination was found useful by Almlid and Johnson (1988) for frozen-thawed boar spermatozoa for monitoring membrane damage at the time of evaluation of various freezing protocols. Further, Harrison and Vickers (1990) also noticed that this combination with a fluorescent microscope is effective indicator of viability of fresh, incubated or cold-shocked spermatozoa in boar and ram. Contrasting to these, Garner et al. (1986) was failed to find a relationship between bull sperm viability and fertility when using combination of CFDA/PI . Flow cytometry for evaluating sperm viability appears to be a precious tool in the AI industry. When a high number of sperm is packed in each insemination dose, the effect of selecting the best ejaculates according to sperm viability has a relatively limited effect. However, sperm viability might be more important when combined with low-dose inseminations. The FACSCount AF flow cytometer also determines sperm concentration accurately and precisely during the same analysis (Christensen et al., 2004a). The combined assessment of sperm viability and concentration appears to be useful in the wake of improving quality control at AI stations. Because of the results of this trial, this method has been implemented by Danish AI stations (Christensen et al., 2005). Relatively bright fluorescence was found also in the mitochondrial sheath of living sperm. But the mechanism and mode of action by which SYBR-14 binds to the DNA of sperm is not known. It is know that PI stains nucleic acids by inte rcalating between the base pairs (Krishan, 1975). Viability stains can also be used in conjugation with fluorescently labeled plant lectins for simultaneous assessment of the plasma membrane integrity and the acrosome integrity (Nagy et al., 2003). It is conceivable that assessment of viability using SYBR-14 dye does not damage spermatozoa, since Garner et al. (5) found that insemination of boar sperm stained with SYBR-14 did not compromise fertilization or even the development of flushed porcine embryos in vitro. Non-viable sperms can be detected using the membrane-impermeable nucleic acid stains which positively identify dead spermatozoa by penetrating cells with damaged membranes. Plasma membrane which is intact will not permit these stains entering into the spermatozoa and staining the nucleus. Most frequently used stains include phenanthridines, for example propidium iodide (PI; (Matyus, 1984) ethidium homodimer-1 (EthD-1; (Althouse et al., 1995), the cyanine Yo-Pro (Kavak, 2003) and the bizbenzimidazole Hoechst 33258 (Gundersen and Shapiro, 1984). After a series of comparison between fertility of cryopreserved stallion spermatozoa with a number of laboratory assessments of semen quality as assessed by flow cytometry using PI, Wilhelm et al. (1996) concluded that viability is the single laboratory assay that correlated with fertility. -Sperm plasma membrane integrity Although the sperm plasma membrane covers the entire cell, it consists of three distinct membrane compartments, one which covers the outer acrosomal membrane, one which covers the post acrosomal portion of the sperm head, and one which covers the middle and principal pieces. Sperm membrane is directly or ind Flow Cytometry for the Evaluation of Semen Flow Cytometry for the Evaluation of Semen State of the Art in Sperm Assessment Using Flow Cytometry Abstract Flow cytometry is emerging as a substantial tool in the domain of modern andrology for the routine analysis of spermatozoa. Recent application of flow cytometry in the artificial insemination industry especially for pig is a new approach. Until very recent, analysis of semen samples was routinely performed by microscopical evaluation and manual techniques by laboratory operators; analysis is inclined due to comprehensive variability among observers, influencing its clinical validity. During last decade, to evaluate farm animal semen, variety of new flow cytometric techniques have been intercalated which made possible a wide spread evaluation of several sperm functionality and characteristics. Here in this paper, an initiative has been taken to explore numerous current flow cytometry developments pressing for andrological tests. After the invention of flow cytometry, sperm evaluation by traditional (microscopic) means became questioned and avoided due to the robust advantages of flow cytometry over the microscopic methods. By the recent development of diverse fluroscence probes, flow cytometry became capable of analyzing number of sperm characteristics like viability, capacitation, acrosomal integrity, membrane permeability, membrane integrity, mitochondrial status, DNA integrity, decondensation of DNA and differences between gametes based on sex. The application of flow cytometry to their detection allows increased numbers of spermatozoa to be assessed over a short time-period, provides the opportunity of working with small sample sizes, increases the repeatability of data obtained, removes the subjectivity of evaluation and allows simultaneous assessment of multiple fluorochromes. Thus, flow cytometry is a technique capable of generating significantly novel data and allows the design and execution of exper iments that are not yet possible with any other technique. Nowadays, semen evaluation using laboratory analyses is very meaningful to the artificial insemination industry to provide the most desired quality product to customers. Future development of flow cytometric techniques will permit further advances both in our knowledge and in the improvement of assisted reproduction techniques. In this paper, the main semen attributes that can be analyzed with fluorochromes and adapted for use with a flow cytometer will be reviewed and the relationship of these tests to fertility will be discussed. Introduction Up to now, semen evaluation is considered as the most important laboratory test that has enabled us to identify and predict clear-cut cases of fertility (Jarow et al., 2002), infertility or even of potential sub-fertility (Rodrà ­guez-Martà ­nez, 2007). Determination of the potential fertility of semen sample and, in the long run, of the male from which it has been collected is the ultimate goal of semen evaluations in clinically healthy sires. Now a days, many methods for the estimate the possible fertilizing capacity of a semen sample and, or in the word, of the male (reviewed by Dziuk 1996; Rodrà ­guez-Martà ­nez et al. 1997a; Rodrà ­guez-Martà ­nez and Larsson 1998; Saacke et al. 1998; Larsson and Rodrà ­guez-Martà ­nez 2000; Rodrà ­guez- Martà ­nez 2000, 2003; Popwell and Flowers 2004; Graham and Mocà © 2005; Gillan et al. 2005) are existing. The methods routinely accustomed for evaluation of the quality of a semen sample involved an evaluation of general appearance, volume, pH, sperm concentration, viability, morphology and motility. Most of these evaluations are based on microscopic analyses that only measure relatively a few numbers of spermatozoa within a population. In most of the cases, these are time-consuming; results obtained are controversial and are not translatable. It should also be noted that such conventional techniques are apt to extreme inter-ejaculate variation, even when the laboratory methodology has been standardized. In the wake of this information, new opportunities have arisen for the development of methods for the diagnosis of male infertility, many of which have been shown to exhibit a prognostic value that eludes conventional semen profiling. Moreover, ejaculated spermatozoa are nowadays handled for use in assisted reproductive technologies, such as the artificial insemination of chilled, frozen-thawed or sexed semen, and IVF. During this long processes, number of steps like semen extension, fluorophore loading, ultrav iolet and laser illumination, high-speed sorting, cooling and cryopreservation are followed, which create a scope to impose different degrees of change in sperm functionality followed by suffer of damage to sperm membranes, organelles or the DNA content. Therefore, although several assays have been developed to monitor these sperm parameters, recently it is being claimed by many groups that buck of those so-called procedures are incomplete, time consuming and laborious. Flow cytometry in diverse technical applications proposes many advantages for the analysis of sperm quality. Flow cytometry is a method where multiple fluorescences and light scattering can be induced allowing single cell or particles illumination in suspension while they flow very rapidly through a sensing area. The increasing use over the past decade of flow cytometry in the leading laboratories in human and veterinary andrology has dramatically increased our knowledge of sperm function under physiological and biotechnological conditions. Flow cytometers is capable to acquire data from several subpopulations within a sample in a few minutes, making it perfect for assessing heterogenous populations in a semen sample. Flow cytometry was initially developed in the 1960s, after that flow cytometry is performing automated separation of cells based on the unique recognition of cellular patterns in a population feasible (Hulett et al., 1969). Likewise, cellular patterns can be recognized by utilizing such a separation approach, in each cells within a population (Baumgarth and Roederer, 2000; Herzenberg et al., 2006). The first notion of flow cytometry development was for medical and clinical applications such as haematology and oncology. Although still much research is going on these medical areas and account for the vast majority of publications on this robust technique, but during the past few years it is being used in a diverse areas, such as bioprocess monitoring, pharmacology, toxicology, environmental sciences, bacteriology and virology. Together with elevated use in many areas, recent advancement of flow cytometry increased its application in the reproductive biology especially for andrology. Although flow cytometry may overestimate the population of unlabelled cells (Petrunkina and Harrison, 2009), plethora of research from our group in pig (Pena et al., 2003, 2004, 2005; Spjuth et al., 2007; Fernando et al., 2003; Saravia et al.,2005, 2007,2009; De Ambrogi et al., 2006; ) bull (Bergquist et al., 2007; Nagy et al., 2004; Januskauskas et al., 2003; Bergqvist et al., 2007; Hallap et al., 20 05, 2006;) stallion ( Kavak et al., 2003; Morrell et al., 2008) indicate that newly developed fluorescent stains and techniques of flow cytometry has made possible a more widespread analysis of semen quality at a biochemical, ultrastructural and functional level. Therefore, flow cytometry is the current technical solution for rapid, precisely reproducible assessment of sperm suspensions. In this review we have described potentiality and scope of flow cytometry for the evaluation of semen, and the way in which this technique can be used in clinical applications for andrology based on some of our previous experiences. Definition of flow cytometry The definition of a flow cytometer is ‘an instrument which measures the properties of cells in a flowing stream or ‘an instrument that can measure physical, as well as multi-colour fluorescence properties of cells flowing in a stream. In other word, cytometry is a method which measure physical and chemical attributes of cells or other particles. Such a measurement is made when cells or other particles pass in single file through some sort of measuring apparatus in a stream of fluid. The data obtained can be used to understand and monitor biological processes and develop new methods and strategies for cell detection and quantification. Compared to other traditional analytical tools, where a single value for each attribute is obtained for the whole population, flow cytometry provides data for each and every particle detected. As cells differ in their metabolic or physiological states, flow cytometry allows us not only to detect a particular cell type but also to find different subpopulations according to their structural or physiological parameters. Flow cytometry is a technique for measuring components (cells) and the properties of individual cells in liquid suspension. In essence, suspended cells are brought to a detector, one by one, by means of a flow channel. Fluidic devices under laminar flow define the trajectories and velocities that cells traverse across the detector, and fluorescence, absorbance, and light scattering are among the cell properties that can be detected. Flow sorting allows individual cells to be sorted on the basis of their measured properties, and one to three or more global properties of the cell can be measured. Flow cytometers and cell sorters make use of one or more excitation sources and one or two fluorescent dyes to measure and characterize several thousands of cells per second. Flow cytometry presents objective and precise results (Bunthof et al., 2001; Shleeva et al., 2002), which help to overcome the problems with the manual methods described above. Function and types of flow cytometry A flow cytometer is made of three main systems, fluidics, optics and electronics. ItI It can acquire data on all subpopulations within a sample, making it ideal for assessment of heterogenous population, such as spermatozoa. The adaptation of flow cytometry to sperm assessment came in to function when it was used for measuring their DNA content (Evenson et al., 1980) and its application for analyzing semen has been increased rapidly in last decade. Flow cytometry is now applied for the evaluation semen such as sperm viability, acrosomal integrity, mitochondrial function, capacitation status, membrane fluidity, DNA status and so on. Continuous innovation of new fluorescent stains and techniques facilitated the flow cytometric evaluation of spermatozoa. Flow cytometry allows the observation of physical characteristics, such as cell size, shape and internal complexity, and any component or function of the spermatozoon that can be detected by a fluorochrome or fluorescently labeled compound. The analysis is objective, has a high level of experimental repeatability and has the advantage of being able to work with small sample sizes. Flow cytometry also has the capacity to detect labeling by multiple fluorochromes associated with individual spermatozoa, meaning that more than one sperm attribute can be assessed simultaneously. This feature has an added benefit for semen analysis, as few single sperm parameters show significant correlation with fertility in vivo for semen within the acceptable range of normality (Larsson and Rodriguez-Martinez, 2000) and it is the general statistics that the more sperm parameters can be tested, the more accurate the fertility prediction becomes (Amman and Hammerstedt, 1993). There are two main types of flow cytometers-analysers and sorters are in use. Together with data collection on cells, sorters have the potentiality to sort cells with particular properties (defined by the flow cytometer operator) to extremely high purities. There are also a number of commercial flow cytometers that have been developed for particular analytical requirements. Partec manufacture a Ploidy Analyser and also a Cell Counter Analyser. Optoflow has developed a flow cytometer for the rapid detection, characterization and enumeration of microorganisms. Luminex is developing technology for multiplexed analyte quantitation using a combination of microspheres, flow cytometry and high speed digital processing. Advantages of FC compared to other conventional techniques to explore sperm structure and function Use of authentic assays in the fertility clinic and artificial insemination industries increasing day by day. In this respect, use of flow cytometry might be an important attempt to resolve sustaining problem with so called commonly used manual method for the semen analysis. An additional source of laboratory variation is the low number of sperms analyzed with such techniques. It is worth mentinign here that so called method deal only with few hundred sperm. When we deal with such a few sperm population, there is a possibility that obtained result might not be statistically significant (Russel and Curtis, 1993). The methods which are frequently used are enable to determine sperm concentration (Jorgensen et al., 1997), motility or morphology only (Keel et al., 2002). Objectivity, cell number measured, speed of count and precision are the advantages of flow cytometry to conventional light microscopy techniques (Spano and Evenson, 1993). The technique now a days has been used to determi ne a number of factors including those of acrosome status, membrane integrity, mitochondrial function as well as multiparameter measurement in human (Garrido et al., 2002). Flow cytometry has the ability to analyze thousands of cells in few minutes. In our series of studies, we demonstrated the feasibility and reproducibility of an automated method to evaluate sperm cell type, count, and viability in human boar samples. In our hand, the precision of the flow cytometric analysis is satisfactory in a diverse species (boar, bull, stallion etc), and the observed errors were significantly better than those obtained from the so-called manual methods. Although there are diverse benefits of flow cytometer for the analysis of semen, feasibility of applying flow cytometry sometimes restricted to researcher due to the high outlay and difficulties of operation associated with the requirement of a skilled operator. Further, a flow cytometer is very large and cannot resist shocks associated with movement, and it also requires much space in the laboratory. Whatever may be the limitation, the development of more affordable ‘‘bench-top flow cytometers in recent time raised the potential essentialities to semen analysis. If the further application of flow cytometric analysis is considered further, it might be seen that it is growing popularities as a technique for assessing more than one sperm attribute, simultaneously. Compared to traditional microscopic techniques, flow cytometry analysis is allowing to give a far more simplified and objective method of semen analysis, especially in relation to fertilization with acrosome reactivity potential of spermatozoa (Uhler et al., 1993; Purvis et al., 1990; Carver-Ward et al., 1996). A large number of different techniques to estimate sperm concentration have been reported. In the mid-1990s a series of fixed-depth disposable slides were evaluated as rapid and effective pieces of equipment for the estimate of sperm concentration. Data from a number of preliminary studies proposed that, at least in the 20-mm-depth format, such chambers resulted in a noticeable underestimate of sperm concentration compared to the gold standard (improved Neubauer hemocytometer). According to the World Health Organization that ‘‘such chambers, whilst convenient in that they can be used without dilution of the specimen, might lead to inaccuracy (World Health Organization, 1999). Data from Tomlinson and colleagues indicate that two proprietary disposable slides (Microcell, Conception Technologies, San Diego, Calif; Leja, Leja Products, BV Nieuw- Vennep, The Netherlands) can result in a lower concentrations of sperm compared to the hemocytometer method (Tomlinson et al., 2001) . In contrast, plenty of reports document unacceptable differences between different laboratories and even between different individuals, although fewer studies attempt to address these issues. So, what is wrong? Improvement of semen quality testing has been emphasizing in some reports (Jorgensen et al., 1997; Keel et al., 2000). But due to low number of sperm evaluation by the conventional method results in poor reproducibility. These problems might be overcome when using flow cytometry. The validation of method is a challenge due to its essentiality of having specific, precise, objective, and accurate evaluation to establish a correlation of fertility data or to predict potential of a semen sample accurately (Amann, 1989). In a fertility clinic, precision of data in important as the result of semen analysis is frequently used to manage fertility of a patient and treatment of the unfertile couples. Thus, it is important to take into consideration within and between laboratory variations for successful infertility treatments. Sometimes its a matter of argument that compared to flow cytometry, fluorescent microscopy evaluate â€Å"patterns of fluorescence rather than the fluorescence intensity. Flow cytometer has the lack of ability to discriminate sperm containing a fluorescent marker bound to the equatorial segment or over one of the acrosomal membranes (Parinaud et al., 1993; Mortimer and Camenzind, 1989; Mortimer et al., 1987). Tao et al. (1993) compared flow cytometry and epifluorescent microscopy with various lectins and indicated that there is almost no difference between methodologies for detection of the acrosome reaction. However, it has been argued that lectins do not bind specifically to the acrosomal region of the sperm (Purvis et al., 1990; Holden and Trounson, 1991) and that other binding sites can be easily distinguished by epifluorescence microscopy, whereas flow cytometry identifies the signal from the entire sperm. Additionally, conventional light microscopic semen assessment is increasingly being replaced by fluorescent staining techniques, computer-assisted sperm analysis (CASA) systems, and flow cytometry (PenËÅ"a et al., 2001; Verstegen et al., 2002). Additional advantages over existing techniques are that this approach is faster than the hemacytometer and that cellular debris, fat droplets, and other particulate material in extended semen are not erroneously counted as sperm, as often occurs with electronic cell counters. This method can also be used to determine the number of somatic cells in a semen sample. Application of flow cytometry for sperm count Sperm count is an important predominant factor for the evaluation of sperm fertility potential. Accurate determination of sperm cell concentration is critical especially in AI industry because it provides assurance to customers that straws of extended semen contain the sperm numbers indicated which will help to decide appropriate doze especially for pig. Accuracy of sperm count is a common problem in the andrological laboratories and accurate measure of sperm concentration is particularly important for export in which verification of numbers may be required. Routine sperm counts can help to identify possible processing errors within a specific batch of semen or on a particular day, should those errors occur. As sperm counting procedures become more refined, routine counting can be used to monitor subtle changes in daily semen processing that might affect the number of sperm packaged in a straw. Every time new and more accurate methods for the sperm count determinations are coming and being replaced by the older ones. Some laboratories are trying the Maklerm counting chamber (Se if- Medical, Haifa, Israel) and other improved hemacytometers, such as the MicroCellTM (Fertility Technologies, Inc., Natick, MA); however, these techniques will likely have standard lems similar to those associated with the standard hemacytometers. Although hemacytometers are routinely used for sperm counts, due to the slow process and need for multiple measurements of each sample, the chance of error increase. Freund and Carol (ref) stated that a difference of 20% were not unusual between the determinations by the same technician. Electronic counters provide much more rapid counting, are easier to use, and give more repeatable results among technicians. However, those instruments tend to include in the sperm count any somatic cells present, immature sperm forms, cytoplasmic droplets, debris, and bacteria, thereby inflating the concentration value (Ref). Spectrophotometer is recently being used in the AI industries to assess sperm concentration by determining turbidity of a semen s ample using an instrument previously calibrated for sperm concentration with a hemacytometer or Coulter counter (Ref). The accuracy of this method depends on the methods used for spectrophotometer calibration. Although, sperm concentration can also be determined by spectrophotometrically, the debris present in the raw semen crease problem with misestimation. Sperm number in the frozen thawed semen is difficult to ascertain as most of the extender contain egg yolk particles, fats and other particles which affect measurement of sperm with electric cell counter or spectrophotometers (Evenson et al., 1993). On the other hand flow cytometry created possibilities of a rapid determination of sperm number in a precise form. It is the flow cytometry which can reduce intra-laboratory and inter-laboratory variation and conflict regarding sperm concentration assessment. Computer assisted semen analyzer is robust technique for analyzing sperm movement which can count sperm as well; but such an a nalyzer most of the cases use some counting chamber or hemacytometer which itself can generate error. Although, hemacytometer was originally developed for blood cell counting, its use is now diverse including andrological laboratories for sperm counting. Around two-decade ago flow cytometry was suggested for sperm numbers in straws of cryopreserved bull semen. Christensen et al. (-) observed similar results for sperm count with flow cytometry and hemocytometer for a number of species. Now a day a simultaneous determination of sperm viability and sperm concentration is possible which can avoid the chance of occurring differences between ejaculates leading lack of coordination with field fertility and laboratory analyses. Thus the present technology is more precise which can get rid of variation from handling the sperm sample and variation from pipetting and the analysis itself. Further, Prathalingam et al. (2006) concluded that there is similarities for sperm count result between flow cytometry and two newly approached method (image analysis and fluorescent plate reader) for sperm counting. Though, use of fluorescent plate was emphasized due to low cost and allowing large number of cells counting from a large number of ejaculates. Although flow cytometry has become a valuable instrument for andrological determinations, it is also blamed that sperm concentration by flow cytometry signify a higher value than the real one. The possibility arise might be due to that semen samples often contain some alien materials such as immature germ cells, epithelial cells, blood cells, cytoplasmic droplet, cellular debris etc. In the same way, frozen semen has higher chance to introduce such material as they contain diluents components especially egg yolk particles. These particles and cell debris might have frontal and side light scatter parameters those are similar to spermatozoa. Such sperm-count-overestimation problem arisen in our cases also, especially when we deal with frozen semen. Further it is also claimed that flow cytometry has a tendency to overestimate viable spermatozoa. We are also experienced with such trouble which we guess might be due to that egg particles of extender are considered as viable cell as for it s staining pattern. Our yet to publish data indicate that this problem can be mimic by a centrifugation process and by using low concentration sample for evaluation with flow cytometry. Very recently Petrunkina and Harrison (2009) proposed a mathematical equation for fixing this flow cytometric sperm counting. Thus much research is going on and we hope such discrepancy will completely be resolved near future to get advantage from this robust technology for sperm counting. Flow cytometry for detecting sperm intactness -Viability of spermatozoa The viability of spermatozoa is a key determinant of sperm quality and prerequisite for successful fertilization. Viability of spermatozoa can be assessed by numerous methods, but many are slow and poorly repeatable and subjectively assess only 100 to 200 spermatozoa per ejaculate. Merkies et al. (2000) compared different methods of viability evaluation. They concluded that Eosin-nigrosin overestimate viability while fluorescent microscope and flow cytometry estimate similar trend of viability. Current flow cytometric procedures are able to simultaneously evaluate sperm cell viability together with some other attributes. This method has been successfully used for assessing spermatozoa viability in men (Garner and Johnson, 1995), bulls (Garner et al., 1994; Thomas et al., 1998), boars (Rodrà ­guez-Martà ­nez, 2007; Garner and Johnson, 1995; Garner et al., 1996), rams (Garner and Johnson, 1995), rabbits (Garner and Johnson, 1995), mice (Garner and Johnson, 1995; Songsasen et al., 199 7), poultry and wildfowl (Donoghue et al., 1995; Blanco et al., 2000) and honey bees (Collins and Donoghue, 1999; Collins, 2000) and in fish (Martin Flajshans et al., 2004). Considerable information has accumulated on the use of fluorescent staining protocols for assessing sperm viability (Evenson et al., 1982). The SYBR 14 staining of nucleic acids, especially in the sperm head, was very bright in living sperm. Good agreement was observed between the fluorescent staining method and the standard eosin-nigrosine viability test; the flow cytometric method showed a precision level higher than that of the manual method. One of the first attempts to assess sperm viability utilized rhodamine 123 for determining potentiality of mitochondrial membrane while ethidium bromide for membrane integrity through flow cytometry (Garner et al., 1986). Other combinations that have been used to examine the functional capacity of sperm are carboxyfluorescein diacetate (CFDA) and propidium iodide (PI) (Garner et al., 1988; Watson et al., 1992); carboxydimethylfluorescein diacetate (CMFDA), R123, and PI (Ericsson et al., 1993; Thomas and Garner, 1994); and PI, pisum sativum agglutinin (PSA), and R123 (Graham et al., 1990). The most generally used sperm viability stain combinations is SYBR-14 and PI at present. This stains are now sold commercially as live/dead viability kit. When these two stains are combinely used, the nuclei of viable sperm take fluoresce green and membrane integrity lost cells take red stain. This staining technique has been used in a number of species, including the boar (Garner and Johnson, 1995; Saravia et al.,2005, 2007,2009). Although species differences do exist in the function of spermatozoa, the Live/Dead stain may similarly have no adverse affect on fertilization in the equine, although it remains to be tested in this species. Recently a new instrument (Nucelocounter-SP100) has been introduced to evaluate sperm concentration [11] and viability. Due to the small size and low cost, this instrument has been attracted for field measurements of both concentration and viability. In our hand this instrument was also became useful for the quick measurement of sperm concentration an d viability in stallion (Morrell et al., 2010). Fluorescent probes such as H33258, requiring flow cytometric analysis with a laser that operates in the ultraviolet light range, are less commonly used as this is not a standard feature on the smaller analytical machines. However, one alternative is to use a fluorometer. A fluorometer is a relatively low-cost piece of portable equipment that permits a rapid analysis to be carried out on a sample. Januskauskas et al. (2001) used H33258 to detect nonviable bull spermatozoa by fluorometry and obtained an inverse correlation between the damaged cells per cent and the field fertility. Another option is fluorescent attachments for computer-assisted semen analysis devices. For example, the IDENT fluorescence feature of the Hamilton-Thorne IVOS permits staining with H33258 allowing an assessment of sperm viability to be made along with motility. Fluorochromes used to assess sperm viability by both approach could be utilized in combination with each other. In that case, when CFDA is used combined with PI, three populations of cells as live, which are green; dead, which are red; and a third population which is stained with both and represents dying spermatozoa can be identified. This combination was found useful by Almlid and Johnson (1988) for frozen-thawed boar spermatozoa for monitoring membrane damage at the time of evaluation of various freezing protocols. Further, Harrison and Vickers (1990) also noticed that this combination with a fluorescent microscope is effective indicator of viability of fresh, incubated or cold-shocked spermatozoa in boar and ram. Contrasting to these, Garner et al. (1986) was failed to find a relationship between bull sperm viability and fertility when using combination of CFDA/PI . Flow cytometry for evaluating sperm viability appears to be a precious tool in the AI industry. When a high number of sperm is packed in each insemination dose, the effect of selecting the best ejaculates according to sperm viability has a relatively limited effect. However, sperm viability might be more important when combined with low-dose inseminations. The FACSCount AF flow cytometer also determines sperm concentration accurately and precisely during the same analysis (Christensen et al., 2004a). The combined assessment of sperm viability and concentration appears to be useful in the wake of improving quality control at AI stations. Because of the results of this trial, this method has been implemented by Danish AI stations (Christensen et al., 2005). Relatively bright fluorescence was found also in the mitochondrial sheath of living sperm. But the mechanism and mode of action by which SYBR-14 binds to the DNA of sperm is not known. It is know that PI stains nucleic acids by inte rcalating between the base pairs (Krishan, 1975). Viability stains can also be used in conjugation with fluorescently labeled plant lectins for simultaneous assessment of the plasma membrane integrity and the acrosome integrity (Nagy et al., 2003). It is conceivable that assessment of viability using SYBR-14 dye does not damage spermatozoa, since Garner et al. (5) found that insemination of boar sperm stained with SYBR-14 did not compromise fertilization or even the development of flushed porcine embryos in vitro. Non-viable sperms can be detected using the membrane-impermeable nucleic acid stains which positively identify dead spermatozoa by penetrating cells with damaged membranes. Plasma membrane which is intact will not permit these stains entering into the spermatozoa and staining the nucleus. Most frequently used stains include phenanthridines, for example propidium iodide (PI; (Matyus, 1984) ethidium homodimer-1 (EthD-1; (Althouse et al., 1995), the cyanine Yo-Pro (Kavak, 2003) and the bizbenzimidazole Hoechst 33258 (Gundersen and Shapiro, 1984). After a series of comparison between fertility of cryopreserved stallion spermatozoa with a number of laboratory assessments of semen quality as assessed by flow cytometry using PI, Wilhelm et al. (1996) concluded that viability is the single laboratory assay that correlated with fertility. -Sperm plasma membrane integrity Although the sperm plasma membrane covers the entire cell, it consists of three distinct membrane compartments, one which covers the outer acrosomal membrane, one which covers the post acrosomal portion of the sperm head, and one which covers the middle and principal pieces. Sperm membrane is directly or ind