The Effects Of Radiation On Public Health - 2064 Words

The Effects of Radiation in the Environment on Public Health Introduction Radiation in the environment is widespread and a necessary process for the existence of life. We encounter it from natural sources like the sun or from modern technology such as computed tomography better known as CT scan, and nuclear power plants. Radiation from sunlight is essential but too much of it can be harmful, just as the use of radiation in CT scans. Computed tomography can provide lifesaving information about disease but can also cause disease. One of the topics that every so often pops-up in the news is radioactive waste management and protecting the public against the hazards of radioactive waste from power plants and other facilities that produce radioactive waste. People want to know where is this waste disposed and/or stored and who has access this material. Many of the concerns center around the dangers of radioactive leaks and exposure; consequently, most people do not want this material in their neighborhood. Another concern is the use of waste material as nuclear weapons by terrorists. The disposal and managing of radioactive waste is extremely complicated, not only because of the dangers hazardous waste poses, but also because of the strict compliance the management of this waste must undergo. If radioactive hazardous waste is compliant with the regulations of all the governing federal agencies, it does not pose an environmental public health risk. This paper will discussShow MoreRelatedThe Radiation And Its Health Effects861 Words   |  4 PagesAfter reviewing the Radiation and Its Health Effects section, review the health effects and expected life lost graph. How many days or years does an average person lose due to radiation exposure versus cigarette smoking? Were you surprised by the number of days or years lost to radiation versus cigarette smoking? Why or why not? From the table, the life expectancy lost annually due to a typical background radiation of 360 millirems is 18 days compared to 6 days for smoking a pack of cigarette a dayRead MoreThe Effects Of Radiation Exposure On The Environment1542 Words   |  7 PagesThroughout history, populations have been affected by the devastating effects of radiation disasters. Chernobyl in 1986 and Fukushima in 2011 are a few radiation disasters that will be highlighted. Chernobyl could be argued as one of the worst incidents of radiation exposure to the general public. Aspects of this paper include background on accidents, the effects of the radiation exposure, and the impact of the population living within the areas. As well as the cost, not only economically but environmentallyRead MoreHealth Care Issues: Radiation Exposure and Acute Radiation Syndrome1647 Words   |  7 PagesRunning Head: Health Care Issue Health Care Issue With the advancement of technology, medical sciences have also reaped benefits out of the advanced and systematic techniques and methods for treatment. One such advancement comes in from radiation development and treatment for a number of diseases that were difficult to diagnose and present a treatment. Radiation therapy has been discovered to be the most effective treatment of cancers and is known to be the most viable and frequently used treatmentRead MoreHow Much Radiation Levels Of Millerem The Public1704 Words   |  7 Pages Our research conducted is primarily to collect as much research as possible by conducting surveys by the general public such as students and school staff. The surveys conducted have helped to gather a better understanding of how much radiation levels of millerem the public consumes on a daily basis and how much is safe or not to the point where an individual can get radiation poisoning. We will be analyzing at how much daily activities does per year by simple task such as getting an X-ray threeRead MoreNegative Effects Of Cell Phones1192 Words   |  5 PagesIn this day and age, more than half of the worlds population owns and uses cell phones. It is a well-known fact that cell phones emit low doses of radiation each time one is used, however, people tend to brush it off and not think about the long-term effects it may have. Its only small doses, what harm can come from it? That is a question us cell phone users may ask ourselves, yet never really look into or research. Maybe its be cause we choose not to know the actual truth and just focus on theRead MoreTheu.s. Army Corps Of Engineers1566 Words   |  7 Pagesa nuclear reactor, such as the Manhattan Project. Following the creation of the plutonium, shipments were sent to Los Alamos, New Mexico, to fuel the first atomic detonation. Scientists and military officials were worried about the radiological effects from the detonation, therefore conducted the testing â€Å"210 miles south of Los Alamos, (which) was only twenty miles from the nearest offsite habitation† (U.S. Department of Energy, n.d.). Observers of the Trinity detonation, in July 1945, removedRead MoreEffects Of Electromagnetic Radiation On Human Life853 Words   |  4 Pagesemission, Effects of the Electromagnetic Radiation (EMR) on the humans health is one most significant concern in the world. The present paper recognize of the possible health hazard on the humanity by exposure of Electromagnetic radiations (EMR). Potential of el ectromagnetic radiation can radiate through transmission lines which are very close to human’s life. The effects of the radiations are classified to two main categories that are known as ionization and non-ionization radiation may haveRead MorePublic Health Problem : Light Coming From The Sun1315 Words   |  6 PagesPublic Health Problem â€Å"Radiation is energy that travels as a wave or particle (Thompson E.G., Hahn C, 2013). Different types of radiation exists, light coming from the sun being the most common source known to people. Thus, society is exposed to radiation on the daily basis. Ionizing radiation, in particular, can be harmful - depending on the source and the degree of exposure. (Thompson E.G., Hahn C, 2013). DNA mutations can occur when ionizing radiation is absorbed by a human cell, causing theRead MoreThe Use Of Radiation And Its Effects On Living Organisms1333 Words   |  6 PagesR. Simpson Health Physicist Radiation has been present since the birth of the universe. Upon its discovery in the early 19th century, humans have used radiation for its beneficial purposes that date back decades. However, when used precariously or in large quantities, radiation can be dangerous. It can cause detrimental effects to living organisms. Medical facilities, nuclear power plants, research laboratories and academic industries all need professionals who understand radiation hazards, asRead MoreEssay on The Disaster at Chernobyl844 Words   |  4 Pagesproduced the opposite effect. Instantly, the nuclear core surged with power. At 1:23 p.m., the reactor exploded. The first blast ripped off the reactors steel roof. The second blast released a large plume of radiation into the sky. Flames engulfed the building. For ten long days, fire fighters and power plant workers attempted to overcome the inferno. Thirty-one of them died of radiation poisoning. Chernobyl was the worst nuclear disaster in history. I t unleashed radiation hundreds of times greater

Factors That Facilitate Adult Development And Change Essay

In considering major factors that facilitate adult development and change, it is helpful to conceive of an overarching assumption about learning: it is best achieved through collaboration and dialogue with other professionals. This assumption holds that â€Å"adults have enough life experience to be in dialogue with any teacher, about any subject, and will learn new knowledge or attitudes or skills best in relation to that life experience† (Knowles, 1970, as cited in Vella, 1994 book, p. 3). This dialogue, in turn, must be characterized by a mutual recognition of the psychological and sociocultural aspects of learning that affect individuals. Bee (Bee, 1996, as cited by Baumgartner Merriam, 2000) suggests that these aspects include the psychological components of intelligence and personality, as well as the sociocultural components of race, ethnicity, gender, social class, and education. In promoting effective learning and successful change, we must develop supports for t hese factors and understand that each element will exert varying degrees of influence, depending on the individual. Adult learning is a fluid process, further complicated by issues such as current life stage, health, and the perception of self within the constructs of culture, family values, and recently, a disintegrating global economy. These conditions affect development, learning, and change in varying ways and degrees. Adult learning and transformation is a lifelong process, as each person is aShow MoreRelatedThe Growth And Expansion Of Information Technology Essay1111 Words   |  5 PagesThe growth and expansion of information technology has transformed social and work life and this has influenced changes in personal growth and learning. To adapt to these changes, adult learners must adopt self-directed learning skills to help in their education as well as work life. Besides, instructors play a critical role in helping students to develop self-directed learning skills. Mer riam (2001) defines self-directed learning as the process in which an individual takes a personal initiativeRead MoreWhat Is Evidence Based Practice To Facilitate Organizational Change1108 Words   |  5 Pagesthe end of this course I will demonstrate commitment to the use of evidence based practice to facilitate organizational change. This goal was met as my questioning attitude has spread outside my practice area and into the leadership councils I serve on. In one of my counsels we are re-addressing how nurses are recognized within our organization and are in the data collection phase of new policy development. Another counsel I serve on we have started to research steps to reduce medication errors, specificallyRead MoreAdult Workforce Training Sessions Deals With The Training Session1104 Words   |  5 PagesIntroduction: Adult workforce training sessions deals with the training session of adults in an organized way. The basic purpose of these training sessions is to assist adults in the matter of self-efficiency level and enhancement of their productivity in the different sectors of education. The department of labor and regulation demonstrate these types of training and promote educational levels. The purpose is to increase the understanding levels of different matters, enhancement of educational andRead MoreThe Unemployment Of Young People1706 Words   |  7 Pagesadvocacy where individuals are able to contribute to structural changes in systems, thereby empowering them (Dalrymple 2005, p. 5). Unemployed young people can be defined as individuals aged between 15 and 24 who are without a job and actively seeking part time or full time work (Singell and Lillydahl 1989, p. 458). A central question on the nature of this issue is what factors increase unemployment of young people, and in what way these factors can be addressed. In this essay it is contended that increasedRead MoreInfluence Of Peer Culture On The Social Interaction Of High Schools Students892 Words   |  4 Pageschildren and the culture of adults in that setting. He suggested that there was a dynamic interchange of elements between the two cultures, with elements that appeared in one culture reappearing in the other. Corsaro and Donna Elder (1991) discussed how this interchange between cultures is particularly interesting in adolescence, during which the adolescent peer culture while maintaining its own unique social system, introduces systems and rules that facilitate belonging in the adult society. While contactRead More Second Language Acquisition in Childhood Essay1214 Words   |  5 Pagesstage of development. During development, a child begins to show signs of verbal communication, usually starting out as cooing, babbling, recognizable words, and later two or more word sentences. This occurrence is also seen in the development of second languages. Second language acquisition is the study of how second languages are typically developed. The process of acquiring our native language is very similar and influential to the development of a second language. The development of a secondRead MoreThe Learning Theories Of Teaching Practice Within Classroom Essay1601 Words   |  7 Pagesinto the statement ‘Effective teachers need a range of strategies to ensure that students learn’. Crucially using personal beliefs about learning as well as teaching to reflect on these beliefs as well as considering their influence of developmental factors within the classroom. Learning as a whole can be quite different, ranging from memorisation of classroom information, all the way to being able to connect idea’s together, perform complex activities. As well as interacting with others. While it isRead MoreWhat Drives Adult Personality Development?1542 Words   |  7 PagesOrth, Reitz and Zimmerman’s article (2014) What Drives Adult Personality Development? A Comparison of Theoretical Perspectives and Empirical Evidence In terms of adult personality development, the most prominent perspectives utilize genetic and environmental factors into their models. Some examples of these theories consist of the five factor theory of personality and neo-social analytic theory (Specht et al., 2014). McCray and Costa’s five factor theory focuses on biological maturation and not lifeRead More##t, Piaget And Vygotsky, Repactivism And Constructivists731 Words   |  3 Pagesinterpersonal, and cultural-historical aspects (Brown, 2017). He proposed that social structures and relations lead to development of mental functions. He developed the Zone of Actual Development (ZAD) which is when a student is able to complete a task on their own. There is nothing new to learn. He also developed the Zone of Proximal Development (ZPD) which is dependent on adults or peers to provide assistance because the student is unable to complete the assignment without help. Both Piaget andRead MoreTransformational Learning Essay1027 Words   |  5 PagesTransformational Learning Transformational learning is a philosophy of change. It identifies people why change is necessary, what benefits will be accrued by changing, how to change, and most importantly, how to incorporate and embrace change in education. The study of transformational learning emerged with the work of Jack Mezirow (1981, 1994, 1997). Transformational learning is defined as learning that induces more far-reaching change in the learner than other kinds of learning, especially learning

An image of ones own Essay Example For Students

An image of ones own Essay At an Atlanta festival, black America through the eyes of black artists I hardly go to the theatre these days. Why do these younger black writers have to use so much cussin and crotch-grabbin, and men calling each other nigger every other word? The question was posed by the distinguished older woman in the seat beside me the matron, it turns out, of an established black Atlanta family and mother of Ivy-educated doctors and lawyers. Happily for her, the presentation we were waiting to see that sultry afternoon at the 1992 National Black Arts Festival in Atlanta was scrupulously inoffensive a worthy drama rich in its representation of solid family values. By contrast, in the play I saw later that evening, expletives were tossed about as freely as frisbies at a summer picnic and crotch-grabbing was de rigeur. My matronly neighbor would have undoubtedly escaped at intermission, retreating to the protective walls of positive imagery of Black Folks. Such imagery was in plentiful supply, side-by-side with rougher, more cutting-edge work, Aug. 3-9 at the biennial festival of performance, visual arts, music, dance, film, literature and folk arts. Inaugurated in 1988 as a cultural encore to that years Atlanta Democratic National Convention, the festival was conceived by the Fulton County commissioner as a forum for artists of African descent from here and abroad. At venues throughout the metro Atlanta area, jazz concerts showcased living legends such as Tito Puente and Max Roach; film retrospectives highlighted the achievements of Ousmane Sembene of Senegal and Sergio Giral of Cuba (both of whom were present at the festival); a two-day Roots and Branches folk arts festival represented the evolution of African culture through reproductions of West African and Caribbean villages, a Gullah settlement from the Carolina coast, and a black Seminole village of Texas. If the NBAF can be said to have a theme, it is the discovery of what it means to be black in America articulated by as many different, passionate voices as can be brought together at one time. This year, stereotypes were confronted and avoided, parodied and mythologized, deconstructed and denounced; depictions of the burgeoning black middle class (the aforementioned positive images) had their moments onstage, as did those of angry, inner-city black males. But unlike the portrayals we are accustomed to seeing on television and in movies, these were all created by black people. Audiences which counted among their numbers well-bred southern debutantes; younger, hipper Atlantans; visitors from across the country pricked up their ears to the messages behind the performances, keeping the crucial factor of who created them in mind. The festivals theatre agenda encompassed a melange of genres from the splashy Broadway musical The Wiz, featuring Stephanie Mills in a role she created almost 20 years ago; to the South African musical Sheilas Day, directed by Mbongeni Ngema; to a trio of staged readings by Laurie Carlos, Paul Carter Harrison and Glenda Dickerson; to performance art by more obscure but provocative artists such as the Hittite Empire of Los Angeles. The latter group, a hard-hitting, no-holds-barred ensemble of about a half-dozen men and one woman, presented a new work called River as part of a performance-art series trendily titled Blue Light Basement: From Jukehouse to Funkhouse. The Hittites aim to articulate the New Black Aesthetic as well as address current problems in the black community in the words of its leader Keith Antar Mason, to explore our hidden mysteries and mythologies in order to understand ourselves better. River is a ritualistic performance that begins with the displaced voice of Mason echoing from backstage. Is it hard for you to breathe out there? he intones, as the small theatre fills with the scent of heavy incense. Can you breathe in history, Atlanta? In the course of relating what Mason characterized as the true story of a black American filmmaker who went to seek artistic freedom in Berlin in the 1930s and became a beloved artist of Hitlers, four actors relentlessly demonstrate the goose step; when Hit ler talks of his New World Order and the ascent of the Aryan race, the black film. makers response is a deadpan, America has already beat you to it. (At a Q--A session after the show, Mason indicated that the artists story could be found on page 119 of a book called Negro Film Makers. A thorough check of the Atlanta-Fulton Public Library the following day uncovered no such text, however.) River goes on to deal intelligently with another issue too often left unaddressed-relationships between black men and black women. If I could find one black man who loves me, a lone woman laments; she moves into a sensual, spasmodic dance behind a scrim resembling a gigantic spiders web, while the four men onstage clutch bottles to their chests and drink themselves into a spiritual abyss. .u34eb24dfd3a571f627e44514bad673e9 , .u34eb24dfd3a571f627e44514bad673e9 .postImageUrl , .u34eb24dfd3a571f627e44514bad673e9 .centered-text-area { min-height: 80px; position: relative; } .u34eb24dfd3a571f627e44514bad673e9 , .u34eb24dfd3a571f627e44514bad673e9:hover , .u34eb24dfd3a571f627e44514bad673e9:visited , .u34eb24dfd3a571f627e44514bad673e9:active { border:0!important; } .u34eb24dfd3a571f627e44514bad673e9 .clearfix:after { content: ""; display: table; clear: both; } .u34eb24dfd3a571f627e44514bad673e9 { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .u34eb24dfd3a571f627e44514bad673e9:active , .u34eb24dfd3a571f627e44514bad673e9:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .u34eb24dfd3a571f627e44514bad673e9 .centered-text-area { width: 100%; position: relative ; } .u34eb24dfd3a571f627e44514bad673e9 .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .u34eb24dfd3a571f627e44514bad673e9 .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .u34eb24dfd3a571f627e44514bad673e9 .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .u34eb24dfd3a571f627e44514bad673e9:hover .ctaButton { background-color: #34495E!important; } .u34eb24dfd3a571f627e44514bad673e9 .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .u34eb24dfd3a571f627e44514bad673e9 .u34eb24dfd3a571f627e44514bad673e9-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .u34eb24dfd3a571f627e44514bad673e9:after { content: ""; display: block; clear: both; } READ: Road to recovery or road to nowhere EssayThe hero of Paul Carter Harrisons Goree Crossing has fallen into his own spiritual void, but meets his salvation in a southern backwash, circa 1918. A staged reading of the work about racial violence, directed by Negro Ensemble Company founder Douglas Turner Ward, was presented as part of the festivals New Play Project, a component of the festival that will begin commissioning plays for 1994. In what might be described as a blues/spirituals operetta, Harrisons protagonist, Chap Chapman, is a sidditty Negro from up North, a vaudeville star who thinks hes too highbrow to associate with the country Negroes of Goree Crossing. Chap arrog antly performs show tunes like Im just a Hottentot and Jim Crow and callously lashes out at the voodoo-practicing niggas around him until the lynching of a mulatto man in town precipitates a crisis. Too long (nearly four hours) in its present form, the play is nevertheless lush with mythological elements (a young woman tells a story of a magical river where blacks washed to become white) and in this reading benefitted from a talented cast and chorus. Ward himself shone as Papa Da, a scary old man who lives in a mudhole and becomes the deus ex machina during the plays intoxicating finale. A vastly different depiction of life in a southern town is offered in Valetta Andersons Shell Find Her Way Home, premiered by Atlantas Jomandi Productions in February of 1991 and remounted for the festival. Based on the true story of a family of former slaves who owned three plantations in pre- and post-war Mississippi, Shell Find Her Way Home traces the founding of an all-black town, Mound Bayou, Miss., in the 1880s. Suggests playwright Anderson, I want to write stories about overcoming, about other elements of our history. In particular, the story of the black middle class has been missed. Not everyone was dealing with overseers and an animalistic mentality. Anderson is currently at work on a trilogy about this unacknowledged aspect of black American history. Alonzo D. Lamont Jr.s Vivisections from the Blown Mind, first produced at Washington, D.C.s Arena Stage in 1991 and presented at the festival by Atlantas 7 Stages under Clinton Turner Daviss direction, fast-forwarded audiences into the harsh realities of life for the 1990s black male. Castro, a young rap artist, is no product of the ghetto (his mom is a teacher, his dad an engineer, and he is college-educated), but he must play the role of the gangsta rapper in order to succeed in white-dominated Hollywood. His relationship with Angelique, the smart, sexy white woman who strategically handles his affairs, is reminiscent of that between Lula and Clay in Amiri Barakas seminal 1964 work Dutchman, in which the white woman, through a cunning game of sexual politics, attempts to penetrate the psyche of a black man. Castro is also a movie actor, and the signature moment of his action-adventure flicks is also his greatest source of humiliation: In classic Steppin Fetchit fashion with bugged eyes and wide grin Castro is called upon to point a gun at his enemy and proclaim, I aint be dead, eat lead. Castros identity is caught in a vortex between the hilariously exaggerated stereotypes of the past and the more subtle but no less damaging portrayals of the present-day black man. Playwright Lamont makes no apologies for the powerful language (not to mention crotch-grabbing) put to the service of telling his story, but he betrays more than a touch of cynicism about black audience reaction to Vivisections and the state of black theatre in general. With black drama these days, if its not about sisterhood, theres not much of a chance for success, he observes. When you have a black man onstage, people are prepared to take an unintellectual journey. Standards are lowered. They are dealing with the image and not with the language. .ua39761f1e855eb7ba25105c9f54f94b9 , .ua39761f1e855eb7ba25105c9f54f94b9 .postImageUrl , .ua39761f1e855eb7ba25105c9f54f94b9 .centered-text-area { min-height: 80px; position: relative; } .ua39761f1e855eb7ba25105c9f54f94b9 , .ua39761f1e855eb7ba25105c9f54f94b9:hover , .ua39761f1e855eb7ba25105c9f54f94b9:visited , .ua39761f1e855eb7ba25105c9f54f94b9:active { border:0!important; } .ua39761f1e855eb7ba25105c9f54f94b9 .clearfix:after { content: ""; display: table; clear: both; } .ua39761f1e855eb7ba25105c9f54f94b9 { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .ua39761f1e855eb7ba25105c9f54f94b9:active , .ua39761f1e855eb7ba25105c9f54f94b9:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .ua39761f1e855eb7ba25105c9f54f94b9 .centered-text-area { width: 100%; position: relative ; } .ua39761f1e855eb7ba25105c9f54f94b9 .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .ua39761f1e855eb7ba25105c9f54f94b9 .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .ua39761f1e855eb7ba25105c9f54f94b9 .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .ua39761f1e855eb7ba25105c9f54f94b9:hover .ctaButton { background-color: #34495E!important; } .ua39761f1e855eb7ba25105c9f54f94b9 .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .ua39761f1e855eb7ba25105c9f54f94b9 .ua39761f1e855eb7ba25105c9f54f94b9-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .ua39761f1e855eb7ba25105c9f54f94b9:after { content: ""; display: block; clear: both; } READ: The Greek Theatre EssayLamonts complaint is just one reflection of the myriad approaches to theatre and the productive dialectical process that a festival on the scale of NBAF encourages. What became clear by festivals end is that there is more than one black American experience and more than one viable way to depict accurately our different shades of blackness.

Othello Essay - How Iago is the catalyst for the targedy free essay sample

Analyse how Shakespeare portrays the character of Iago as the catalyst of this tragedy. It is true that in Shakespeare’s Othello, Iago is portrayed as the catalyst and the foremost cause for the events that unfold. Shakespeare portrays this through Iago’s manipulation and power of words, and his continual playing on people’s weaknesses and strengths. This is represented through the impact that he has on other characters, in particular of Othello and Cassio. In Shakespeare’s Othello, the character of Iago is portrayed as one of pure evilness, a man who sets out to destroy the other characters and turn â€Å"virtue into pitch† (II, iii, L 343) with no real motive, seemingly just for fun: â€Å"for my sport and profit† (I, iii, L380). Iago is also portrayed as a manipulative and devious character, constantly being likened to a scheming spider through the imagery depicted in his soliloquys: I shall â€Å"make the net/ That shall enmesh them all,† (II, iii, L 343-344). We will write a custom essay sample on Othello Essay How Iago is the catalyst for the targedy or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page However, not a single character in Othello has any idea of Iago’s true character. He is of high status in the Venetian military and has earned the trust of everyone, as seen through their constant repetition of the fallacious epithet honest: â€Å"A man he is of honesty and trust† (I, iii, L 284). Through this deception of â€Å"I am not what I am† (I, i, L 65), Iago is able to psychologically manipulate and control characters and so is portrayed as the catalyst behind the events that unfold. Shakespeare’s Othello also portrays Iago as the catalyst behind the tragedy through his impact on Othello. Othello at the beginning is a man of eloquence and accomplishment, and is essentially at the peak of his personal and professional achievements. He is dignified and rational, as seen through his reaction to Brabantio’s threats: â€Å"Were it my cue to fight/ I should have known it,† (I, ii, L 83). However, Iago is able to carefully and masterfully entrap Othello into believing that his wife, Desdemona, is having an affair with his lieutenant, Cassio. He plays on Othello’s goodness of a â€Å"Free and open nature† (I, I, L 393) and thinking â€Å"men honest that but seem to be so,† (I, i, L 394). This, as well as his close proximity and his aforementioned deceptive reputation, entice Othello to trust his words, however foul they may be, and through his language of manipulation, Iago is able to psychologically control Othello. Iago realises that Othello, like all tragic heroes, has a fatal flaw, which in this case is provoked jealousy. Thus he plays on Othello’s vulnerable state of being an outside figure and a subject of scrutiny to manipulate and spark jealousy inside of him: â€Å"She did deceive her father, marrying you†¦Ã¢â‚¬ ¦She loved them most,† (III, iii, L 205-207). Furthermore, Iago never states overtly. He merely echoes Othello and leads him to draw his own conclusion through allusions. This is depicted when Iago subtly reminds Othello of Desdemona: â€Å"My friend is dead†¦.. but let her live† (III, iii, L 106-107). The full impact which Iago has on Othello is shown through the contrast of Othello’s language from the beginning and towards the end of the play. Iago’s animalistic and hellish lexicon have infected Othello that even he, a once eloquent man, uses similar language: â€Å"â€Å"I will chop her into messes! † (IV, i, L 106). Furthermore, Iago is portrayed as a representation of a devil on Othello’s shoulders. His manipulation was so successful that he acts as Othello’s conscience towards the end of the play, as depicted through his ability to control Othello into killing Desdemona by his method of liking: â€Å"Do it not with poison/ Strangle her in her bed,† (IV, I, L 202). Thus, it can be determined through Iago’s impact on Othello how Shakespeare has portrayed Iago as the catalyst in Othello. Iago’s impact on another character, Cassio, also depicts how Iago is portrayed to be the catalyst in Shakespeare’s Othello. Cassio is described as a man who â€Å"hath a daily beauty in his life,† (V I, L 20) and is also the man who won his abovementioned position over Iago. This jealousy provokes Iago to destroy Cassio in every way. Similar to Othello, Iago uses his words of manipulation to play on Cassio’s weakness of drinking and strength of being an honourable and trustworthy man. He does so by convincing Cassio to drink for his superior, Othello, something a man of Cassio’s honour can’t turn down: â€Å"Tis a night of revels: The gallants desire it,† (II, iii, L 39-40). Cassio’s repetition of â€Å"Reputation, reputation, reputation! † (II, iii, L 252) depicts the vital importance of it to him, and Iago plays on this desire to regain it by convincing him to talk to Desdemona and making her plea to Othello on his behalf. Although Iago rightfully says â€Å"this advice is free I give and honest,† (II, iii, L 320), through the dramatic irony continuously created in his soliloquys, the responders are forewarned of the true intentions behind every action. In this case, Iago explains how he will â€Å"Pour this pestilence in his (Othello’s) ear†¦.. for her body’s lust,† (II, iii, L 339-340). Iago is also able to take advantage of circumstances which therefore impacts on characters, especially Cassio. An example of this is how Iago plants Othello’s handkerchief in Cassio’s bedroom. This handkerchief, a prized possession of Othello’s which he gave to Desdemona, is a symbol of Othello’s, and to a lesser extent Cassio’s, downfall as it is the final proof needed to break Othello. Furthermore in the final act when â€Å"[Iago darts from concealment behind Cassio, wounds him in the leg, and exit]† (V, I, L29-30), it shows how through his stage directions, Iago is able to impact on Cassio and always be an instigator while always lurking in corners and in the shadows to maintain his â€Å"honest† reputation. Hence, it can be seen how Iago’s impact on Cassio has portrayed him as the catalyst in Othello. In Othello, Shakespeare portrays the character of Iago as the catalyst behind the tragedy that unfolds through Iago’s manipulative and deceptive language and nature, which is presented through his impact on the characters of Othello and Cassio.

Language Theories free essay sample

Examines ideas of Ferdinand de Saussure, Jacques Lacan Sigmund Freud related to linguistic, psychological semiotic interpretations of the individual culture. The purpose of this research is to examine the theories of Ferdinand de Saussure, Jacques Lacan, and Sigmund Freud as they relate to linguistic, psychological, and semiotic interpretations of the individual and of the culture as a whole. The plan of the research will be to set forth a summary of Saussures theory of semiotics and the outlines of Freudian psychological theory, and then to discuss the connection between the work of Lacan and Freud in regard to analysis of human subjectivity, as well as the connection between Lacans work to linguistic theory in general and Saussurian semiotics in particular. According to Saussure, language has a dual function. One is public, or a logical and social, while the other is private, imaginative, or psychological. It is in the second manner that creative and imaginative processes may surface, including the

Biography of Francisco Madero, Led Mexican Revolution

Biography of Francisco Madero, Led Mexican Revolution Francisco I. Madero (October 30, 1873–February 22, 1913) was a reformist politician and writer and president of Mexico from 1911 to 1913. This unlikely revolutionary helped engineer the overthrow of dictator Porfirio Dà ­az by kick-starting the Mexican Revolution. Unfortunately for Madero, he was caught between remnants of Dà ­azs regime and the revolutionaries he unleashed and was deposed and executed in 1913. Fast Facts: Francisco Madero Known For: Father of the Mexican RevolutionBorn: Oct. 30, 1873 in Parras, MexicoParents: Francisco Ignacio Madero Hernndez, Mercedes Gonzlez Trevià ±oDied: Died Feb. 22, 1913 in Mexico City, MexicoSpouse: Sara Pà ©rez Early Life Francisco I. Madero was born on Oct. 30, 1873, in Parras, Coahuila, Mexico, to wealthy parents- by some accounts, the fifth-richest family in Mexico. His father was Francisco Ignacio Madero Hernndez; his mother was Mercedes Gonzlez Trevià ±o. His grandfather, Evaristo Madero, made lucrative investments and was involved in ranching, wine-making, silver, textiles, and cotton. Francisco was well educated, studying in the United States, Austria, and France. When he returned from the U.S., he was placed in charge of some family interests, including the San Pedro de las Colonias hacienda and farm, which he operated at a profit, introducing modern farming methods and improving worker conditions. In January 1903, he married Sara Pà ©rez; they had no children. Early Political Career When Bernardo Reyes, governor of Nuevo Leà ³n, brutally broke up a political demonstration in 1903, Madero became politically involved. Although his early campaigns for office failed, he funded a newspaper that he used to promote his ideas. Madero had to overcome his image to succeed as a politician in macho Mexico. He was small with a high-pitched voice, making it difficult to command respect from soldiers and revolutionaries who saw him as effeminate. He was a vegetarian and teetotaler, considered peculiar in Mexico, and an avowed spiritualist. He claimed to have contact with his dead brother Raà ºl and liberal reformer Benito Juarez, who told him to maintain pressure on Dà ­az. Dà ­az Porfirio Dà ­az was an iron-fisted dictator in power since 1876. Dà ­az had modernized the country, laying miles of train tracks and encouraging industry and foreign investment, but at a cost. The poor lived in abject misery. Miners worked without safety measures or insurance, peasants were kicked off their land, and debt peonage meant that thousands were essentially slaves. He was the darling of international investors, who commended him for â€Å"civilizing† an unruly nation. Dà ­az kept tabs on those who opposed him. The regime controlled the press, and rogue journalists could be jailed without trial for libel or sedition. Dà ­az played politicians and military men against one another, leaving few threats to his rule. He appointed all state governors, who shared the spoils of his crooked but lucrative system. Elections were rigged and only the foolish tried to buck the system. Dà ­az had fought off many challenges, but by 1910 cracks were showing. He was in his late 70s, and the wealthy class he represented worried about his successor. Years of repression meant the rural poor and urban working class loathed Dà ­az and were primed for revolution. A revolt by Cananea copper miners in 1906 in Sonora had to be brutally suppressed, showing Mexico and the world that Diaz was vulnerable. 1910 Elections Dà ­az had promised free elections in 1910. Taking him at his word, Madero organized the Anti-Re-Electionist Party to challenge Diaz and published a bestselling book titled  The Presidential Succession of 1910. Part of Maderos platform was that when Dà ­az came to power in 1876, he claimed he wouldnt seek re-election. Madero insisted that no good came from one man holding absolute power and listed Dà ­azs shortcomings, including the massacre of Maya Indians in the Yucatan, the crooked system of governors, and the Cananea mine incident. Mexicans flocked to see Madero and hear his speeches. He began publishing a newspaper,  El Anti-Re-Electionista, and secured his partys nomination. When it became clear that Madero would win, Dà ­az had most of the Anti-Re-Electionist leaders jailed, including Madero, arrested on a false charge of plotting armed insurrection. Because Madero came from a wealthy, well-connected family, Dà ­az could not simply kill him, as he had two generals who had threatened to run against him in 1910. The election was a sham and Dà ­az â€Å"won.†Ã‚  Madero, bailed out of jail by his wealthy father, crossed the border and set up shop in San Antonio, Texas. He declared the election null and void in his â€Å"Plan of San Luà ­s Potosà ­Ã¢â‚¬  and called for armed revolution. November 20 was set for the revolution to begin. Revolution With Madero in revolt, Dà ­az rounded up and killed many of his supporters. The call to revolution was heeded by many Mexicans. In the state of Morelos,  Emiliano Zapata  raised an army of peasants and harassed wealthy landowners. In the state of Chihuahua,  Pascual Orozco  and  Casulo  Herrera raised sizable armies. One of Herreras captains was ruthless revolutionary  Pancho Villa, who replaced the cautious Herrera and, with Orozco, captured cities in Chihuahua in the name of the revolution. In  February 1911, Madero returned from the U.S. Northern leaders including Villa and Orozco didnt trust him, so in March, his force swollen to 600, Madero led an attack on the federal garrison at Casas Grandes, which was a fiasco. Outgunned, Madero and his men retreated, and Madero was injured. Although it ended badly, Maderos bravery gained him respect among the northern rebels. Orozco, at that time leader of the most powerful rebel army, acknowledged Madero as leader of the revolution. Not long after the battle, Madero met  Villa  and they hit it off despite their differences. Villa knew he was a good bandit and rebel chief, but he was no visionary or politician. Madero  was a man of words, not action, and he considered Villa a Robin Hood,  just the man to oust Dà ­az. Madero allowed his men to join Villas force: His days of soldiering were done. Villa and Orozco pushed toward  Mexico City, scoring victories over federal forces along the way. In the south, Zapatas peasant army was capturing towns in his native state of Morelos, beating superior federal forces with a combination of determination and numbers. In May 1911, Zapata scored a huge, bloody victory over federal forces in the town of Cuautla. Dà ­az could see that his rule was crumbling. Dà ­az Quits Dà ­az negotiated a surrender with Madero, who generously allowed the former dictator to leave the country that month. Madero was greeted as a hero when he rode into Mexico City on June 7, 1911. Once he arrived, however, he made a series of mistakes. As interim president, he accepted Francisco Leà ³n de la Barra, a former Dà ­az crony who coalesced the anti-Madero movement. He also demobilized Orozcos and Villas armies. Maderos Presidency Madero became president in November 1911. Never a true revolutionary, Madero simply felt that Mexico was ready for democracy and Dà ­az should step down. He never intended to carry out radical changes, such as land reform. He spent much of his time as president trying to reassure the privileged class that he wouldnt dismantle the power structure left by Dà ­az. Meanwhile, Zapata, realizing that Madero would never approve real land reform, took up arms again. Leà ³n de la Barra, still interim president and working against Madero, sent  Gen. Victoriano Huerta, a brutal remnant of Dà ­azs regime, to Morelos to contain Zapata. Called back to Mexico City, Huerta began conspiring against Madero. When he became president, Maderos only remaining friend was Villa, whose army was demobilized. Orozco, who hadnt gotten the huge rewards he had expected from Madero, took to the field, and many of his former soldiers joined him. Downfall and Execution The politically naive Madero didnt realize he was surrounded by danger. Huerta was conspiring with American ambassador Henry Lane Wilson to remove Madero, as Fà ©lix Dà ­az, Porfirios nephew, took up arms along with Bernardo Reyes. Although Villa rejoined the fight in favor of Madero, he ended up in a stalemate with Orozco. Madero refused to believe his generals would turn on him. The forces of Fà ©lix Dà ­az entered Mexico City, and a 10-day standoff known as la  decena  trgica (â€Å"the tragic fortnight†) ensued. Accepting Huertas â€Å"protection,† Madero fell into his trap: He was arrested by Huerta on Feb. 18,  1913,  and executed four days later, though Huerta said he was killed when his supporters tried to free him. With Madero gone, Huerta turned on his fellow conspirators and made himself president. Legacy Although he wasnt a radical,  Francisco Madero  was the spark that set off the  Mexican Revolution. He was clever, rich, well-connected, and charismatic enough to get the ball rolling against a weakened Porfirio Dà ­az, but couldnt hold onto power once he attained it. The Mexican Revolution was fought by brutal, ruthless men, and the idealistic  Madero  was out of his depth. Still, his name became a rallying cry, especially for Villa and his men. Villa was disappointed that Madero had failed and spent the rest of the revolution looking for another politician to entrust with the future of his country. Maderos brothers were among Villas staunchest supporters. Later politicians tried and failed to unite the nation until 1920, when Alvaro Obregà ³n seized power, the first to succeed at imposing his will on the unruly factions. Decades later, Madero is seen as a hero by Mexicans, the father of the revolution that did much to level the playing field between rich and poor. He is seen as weak but idealistic, an honest, decent man destroyed by the demons he helped to unleash. He was executed before the bloodiest years of the revolution, so his image is unsullied by later events. Sources McLynn, Frank.  Villa and Zapata: A History of the Mexican Revolution.  Basic Books, 2000.Francisco Madero: President of Mexico. Encyclopedia Brittanica.Francisco Madero. Biography.com.

Response to the Discussion by Tamika Case Study Example | Topics and Well Written Essays - 500 words

Response to the Discussion by Tamika - Case Study Example It is essential to develop trust and partnership with the wife of the patient for strengthening and supporting that family through expected and unexpected life events. Therefore, it is important to help Maureen in supporting the interest of the family and she should be given the right guidelines regarding cancer communication. "The family is a significant factor in the health and well-being of individuals, and promotion, maintenance, and restoration of families are important to society's survival." (Registered Nurses Association of Ontario, 2006). Thus, as a nursing practitioner, I would help the wife of the patient to understand the relevance of effective cancer communication and I will collaborate with her in determining the most impeccable resolution regarding this communication. I will convince Maureen not to rush to any futile conclusions and that we will support her in every possible way to offer the best solution to the issue. Thus, after the collaborative discussions and eval uations of the possible courses of actions and their consequences, I will help Maureen to take the right decision regarding the information being withheld from her husband. In her discussion of the specific case provided, Tamika makes some essential points regarding effective cancer communication to the patient and the issues related. At the very start of the discussion, Tamika mentions the possibility of the errors in the decision of Maureen to withhold the information from the patient, while she accepts the situations leading to the wife’s decision.  Ã‚  

Whole food study case Example | Topics and Well Written Essays - 250 words

Whole food - Case Study Example gh it recovered and has started increasing its profits from an average of $300 million to $500 million, it has yet to clear its debts of over $700 million which were accumulated during the period mentioned above. There are several ways to solve this problem and ensure that even if the economy plunges again, they will have no debts accumulating on top of what they have now. The first way is to dispose of some of their assets which are not helping them much through selling them. This is bound to bring in a bit of money to offset the debt. The other way is to increase the number of shares to the public and this will raise money. It can also increase gradually the prices of their commodities especially now that people like the natural and organic products they sell. Even if the money will not repay all the debt, it will at least offset a large sum of money and the rest can be paid off slowly through the proceeds from the company. Thompson, Arthur, Margaret Peteraf, John Gamble and A. J. Strickland. Crafting & Executing Strategy: The Quest for Competitive Advantage: Concepts and Cases. New York: McGraw-Hill Education, 2011.

Healthy life Essay Example for Free

Healthy life Essay Many of the views associated with a healthy lifestyle, but it is not appropriate that we take for granted about this healthy lifestyle . 1 . Caring for Daily Nutrition ( menJaga keseimbangan makanan) Among healthy lifestyle is keeping our daily diet . Therefore, we should adopt a balanced diet . Balanced diet allows our bodies healthy and not overweight. Poor diet causes our body to get a variety of diseases such as hypertension , heart disease and diabetes. Exercise or Play ( bersenam atau beriadah) In addition, we also must diligently work or play. By doing physical activity , the heart will be healthy and strong. Toxic waste in the body will come out through our sweat during exercise . Exercise we are doing will allow the blood to flow properly and strengthen the muscles of the body . 3 . Environmental Cleanliness and Environment Home Practice a healthy lifestyle is keeping the house clean next and the environment. Places that allow mosquitoes to breed must be eliminated. All refuse shall be dubuang to Famous Spots: Yoy reserved . Do not throw garbage into the river or dibaar outdoors because it can cause environmental pollution . 4 . Health Inspection (pemeriksaan kesihatan) In addition, we need to make health checks. Health checks can be made public or private hospital . By knowing our health , we can already taken measures to ensure our health continues to be in good keaaan . Checks can be made two one-year time . 5 . Avoid Doing Affect Health We must also avoid actions that could affect health. Among the things that can affect health is cigarette smoking , alcohol and drugs. The habit of smoking cigarettes can ause a lung disease and heart disease. While drug addiction can lead to social and community causes disease , an obstacle to the progress and development of the country , so let us increase our awareness and understanding of the dangers of drugs , and trying to control and prevent the occurrence of these adverse events . In conclusion , there are some practices that we need to do to enable us to live a healthy life . Practice a healthy lifestyle should be nurtured since we were little where parents and family members to play their role in a healthy lifestyle . So prevention is better than cure. healthy life.

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