Sustainability Accounting and Accountability Theory

Question: Examine about the Sustainability Accounting and Accountability Theory. Answer: Presentation: Bookkeeping Researchers had demonstrated extraordinary enthusiasm from where governmental issues influences bookkeeping standard-setting process (Pratt 2013). This implies easygoing perception of the standard-setting process recommending legislative issues and administrative exercises influences setting of bookkeeping measures. As it were, Researchers significantly creates just as test given monetary based hypotheses of standard setting for catching the political variables. The fundamental objective depends after blending experimental exploration chiefly in governmental issues of standard setting at FASB (Financial Accounting Standards Board). This focuses on plainly understanding the legislative issues of standard setting for investigating on the advancement level quite far (Dillard and Vinnari 2016). Difficulties It has been seen that there is nobody model that focuses on completely catching the complex financial just as political nature of bookkeeping standard setting. This uncovers models gives vital system particularly to exact work (Deegan 2013). Scientists faces threat in over fitting the information by deciphering given experimental work for predictable supported model. There are different difficulties seen in connection with fitting the hypothesis just as experimental work. There is commonly acceptable arrangement of proof demonstrating the impact of legislative issues particularly on standard setting. It uncovers considering number of models both in US just as on global premise as legitimately influenced by given standard setting results (Bebbington, Unerman and O'Dwyer 2014). These models make it understood for the governmental issues as assuming significant job in standard setting. These difficulties help in giving bigger example as saw in IAS 39. Dangers There have been thoughtful conversations in regards to the proposed new bookkeeping rules for leases. This implies at the danger of over-rearrangements, it considers the current FASB or IASB proposition for promoting the rent exchanges including working leases portrayed to be decided sheet. It help impartial eyewitnesses for getting improvement bookkeeping as in the event of financial substance in numerous leases for indicated period for resource buy financed by obligation (Pratt 2013). A few endeavors have been attempted for taking out the elective bookkeeping medicines for given exchange class. For example, if an individual accepts administrators takes thought in regards to the bookkeeping decisions for flagging private data, it takes out with the capacity from revealing exchanges for lessening enlightening qualities. Issues Plan of standard setters considers as one of the critical determinant of bookkeeping norms for keeping an eye on the bookkeeping issues comprehensive of standard setters. At the end of the day, there are a portion of the questionable bookkeeping issues as tended to by FASB if there should arise an occurrence of oil and gas bookkeeping. For this situation, it was adequately included by FASB plan in understanding the full cost strategy bookkeeping rules (Dillard and Vinnari 2016). Consequently, one of the methodological issues uncovers confining the examples from bookkeeping firms anteroom from the remark letter process. For Instance, general methodology uncovers campaigning in two significant viewpoints, for example, incorporating remark letters in respondent with significant standard setting issues. There are different discoveries found from the elements overseeing political and administrative characteristics, for example, shared trait among the positions (Deegan 2013). There is no solid alliances in and among the constituents in lining up with differed process for increasing comprehension of considerable issues for hidden standard setting process. Reference List Bebbington, J., Unerman, J. what's more, O'Dwyer, B., 2014. Supportability bookkeeping and responsibility. Routledge. Deegan, C., 2013. Money related bookkeeping hypothesis. McGraw-Hill Education Australia. Dillard, J. what's more, Vinnari, E., 2016. A contextual analysis of study: Critical points of view on basic bookkeeping. Basic Perspectives on Accounting. Pratt, J., 2013. Money related bookkeeping in a monetary setting. Wiley Global Education.

Is Torture Ever Ok free essay sample

A great deal of times in these situations there are no different alternatives and tormenting somebody is the best way to get quick outcomes before it is past the point of no return. I am an utilitarian mastermind and I put stock in the best useful for the vast majority. In the event that a great deal of people groups lives are in question in a circumstance and can be spared in view of one hoodlums torment at that point tormenting is the best approach. I accept that torment can be ethically advocated in numerous outrageous conditions and by managing torment by law then it could profit our general public. My first contention will show how torment can be utilized to help stop a burglar who has numerous prisoners. Assume, the specialists captured one of the schemers of the burglar and they werent getting anything out of him. The burglar told the specialists that in the event that they didnt get him a plane out of the nation, at that point he would begin murdering prisoners. We will compose a custom article test on Is Torture Ever Ok? or on the other hand any comparative subject explicitly for you Don't WasteYour Time Recruit WRITER Just 13.90/page The specialists dont know where the burglar is or the prisoners. The burglar says they just have fifteen minutes to mastermind him a plane before he begins killing the prisoners. The specialists could torment the plotters and get the data they have to spare the prisoners and capture the burglar or they could allow the prisoners to bite the dust. This is the reason as I would like to think torment is ethically advocated in this circumstance. The primary contention I utilized shows a genuine case of how tormenting can spare individuals lives, capture a lawbreaker, and keep more individuals from passing on in the short and since a long time ago run. A partner from my last paper, Mirko Bagaric, concur with me. Bagaric is an educator of law at Deakin University and as indicated by him, torment is legitimate when utilized as a data gathering strategy to deflect incredible hazard (Bagaric, p. 264). In my model, it clearly concurs with Bagarics explanation. There are numerous factors that go into whether tormenting somebody in an extreme circumstance is reasonable. Bagaric composed a rundown of these factors: 1. the quantity of lives in danger; 2. the promptness of the mischief; 3. the accessibility of different intends to procure the data; 4. the degree of bad behavior of the operator; and 5. the probability that the specialist really processes the applicable data. I accept that if these were the five principles in a law that controlled torment so we could set a trade off with individuals who figure torment ought to never occur. The main motivation I think tormenting is alright in hurt based circumstances is on the grounds that it is our ethical obligation to spare different people groups lives. As I would like to think, some ethical obligations supersede others. The ethical obligation to spare a huge number of individuals supersedes the ethical obligation to regard someones physical body, who is holding data from you since they need each one of those individuals to kick the bucket. Everybody must concur that the most essential and significant human right is the privilege to life. In the event that you get an opportunity to spare a large number of lives and tormenting is your lone choice then the decision is self-evident. Tormenting must be alright in certain conditions, so as to spare lives. I am not saying that individuals should torment an individual to death since that disregards their entitlement to live. Be that as it may, if the torment just motivations some physical torment to one individual to spare numerous lives at that point torment ought to be ethically and legitimately passable. In Heinz site, at whatever point tormenting somebody there ought to consistently be a specialist there to ensure the individual being tormented isnt slaughtered. I don't think tormenting is in every case alright and it ought to consistently ought to be the last choice, yet when more awful comes to more awful sparing a large number of individuals merits tormenting an individual who approves of those individuals passing on. Individuals who contradict torment consistently are deontologists. Deontologists accept that general guidelines and qualities must be regarded paying little heed to the result. As indicated by them even a savage fear monger who needs to murder their loved ones ought not be hurt since it is unethical to dispense physical torment on somebody. They accept that you ought to never twist the principles regardless of whether it causes passing. Some of them accept that in the event that you permit tormenting that you will begin down a dangerous slant. For instance, this dangerous incline could pave the way to slaughtering a detainee to dodge a bomb going off and murdering thousands. Also, imagine a scenario where, you murdered the detainee and the person in question didnt surrender any data. The elusive incline of erring prompts additionally erring as indicated by deontologists. For them, torment advances savagery and sin. In spite of the fact that, I do concur with a portion of the parts from different sides contention it doesnt change the reality the torment is required in some malignant cases. I concur that you ought not cause someone else physical mischief, yet on the off chance that hurting this individual can spares lives I trust it is ethically alright. Individuals have a more noteworthy good commitment to safeguard our species and protect our family and nation. On the off chance that truly hurting one individual can assist us with doing this, at that point tormenting ought to be worthy. Rivals to torment likewise expressed that we will go down a tricky street to sin and executing individuals being tormented, however I oppose this idea. I accept that we are sufficiently levelheaded to have the option to torment somebody and keep them alive. When tormenting somebody I figure it would possibly be satisfactory if a specialist was available to ensure the individual be tormented didnt kick the bucket. Additionally, I accept we must be 100% positive the detainee has the data we need, in any case; tormenting them would not be right. I realize that tormenting isn't right much of the time yet in ought to be adequate in others. Bagaric states that A legitimate system ought to be set up to appropriately suit these circumstances, (Bagaric 274). If torment somehow happened to be directed rather than restricted, it would bring out more prominent great then it would hurt. Torment happens whether it is denied or not. On the off chance that we make the possibility of a torment warrant in any event we are expressing what we are doing as opposed to concealing it. The best way to get a torment warrant is meet the five factors Bagaric composed. Specialists being available when a detainee is being tormented likewise safeguards that their life is being looked out for cautiously. In this model it shows that torment can be directed to protect we dont tumble down a tricky incline and that it will help spare numerous individuals later on. My subsequent contention shows that guideline of torment is better than precluding it. As I would see it, conceding what you show improvement over lying about it. Torment is banned in Israel yet they have been censured everywhere throughout the world for tormenting individuals, (Dershowitz). They are being dishonest. The United States torments individuals subtly to discover indispensable data. Despite the fact that they attempt to be clandestine about it, they generally get captured. It would be better if everybody realized that torment does occur and needs to in some cases. I concur and wish that we never needed to do it, yet in some cases to spare lives you have. By managing torment, individuals won't be two-faced about it and there will be rules relating to the issue. A conspicuous issue with this contention is once more, the tricky incline. Individuals against torment accept in the event that you make the way for torment, regardless of whether you direct it, you will prompt increasingly more torment. They state regardless of whether you torment is required in outrageous circumstances that making it lawful will permit torment in less edgy circumstances. Once more, I can reply this protest of the elusive slant for managing torment. For one thing, torment is as of now utilized despite the fact that it is lawfully precluded. I think making directing torment will really diminish it. Individuals should get torment warrant and we should ensure those are difficult to get. Second, Bagaric and Clarke state, that there is no proof to propose that the legal infringement of basic human interests will essentially prompt an infringement of basic rights where the per-conditions for the action are unmistakably depicted and controlled. For instance, we utilize capital punishment in the U. S. , yet we despite everything esteem life and havent been executing individuals except if it was for an authentic explanation. Religions, for example, the Muslim-American religion state, It is skeptical, corrupt, and unethical(Rashid 1). They express their strict history is loaded with stories requesting that we censure misuse and torment. The Muslim-Americans state that, The Prophet Moses yielded his illustrious situation to stop a demonstration of torment (Rashid1). They express, the Prophet Muhammad disallowed the abuse of detainees. Torment irritates Muslim-Americans since it is shameless nature. They express that the torment of people at the command of the American government must be denounced. They state that, Simply in light of the fact that another nation permits torment doesn't mean we ought to support and use the ethical shortcoming of others (Rashid 1). They clarify that when we endorsed the Convention Against Torture President Ronald Reagan stated, â€Å"[We] plainly express United States restriction to torment, a loathsome practice lamentably still common on the planet today. † They additionally commend President Obama for sparkling light on these disgraceful practices. At long last they stated, We can't be hard of hearing to the voice of equity, however should build up it. Torment isn't simply (Rashid 2). The Muslim Religion has numerous admirable sentiments, however I differ that torment is never right and unethical. Some of the time awful things can be utilized for more noteworthy's benefit. My dad who was a veteran of the Air Force realizes that it is so imperative to get essential data out of adversaries. My dad accepts, as Bagaric, when numerous lives are in danger and the best way to spare somebody is torment them then you ought to do what is vital. My father has experienced torment preparing. My father expresses that, in the event that the opposite side is going to torment us, at that point we must have to gain proficiency with similar strategies. My dad said in the meeting, that torment ought to consistently be the last alternative, yet when things are turning for the most noticeably terrible then some of the time you simply need to do

3 Essay Anthologies That Arent About Writing

3 Essay Anthologies That Arent About Writing I love reading essays by writers I know and love (and writers Ive never heard of). Its fascinating to get to spend a few pages inside a writers own head, rather than with their characters, or to read the prose of a writer whom I primarily know through their poetry. I also love reading about writing itselfâ€"theres something comforting about seeing my own struggles and frustrations with the art reflected on the page, in the words of published authors. But though I love a good anthology of Writers on Writing, its the books with (hypothetical) titles like Writers on Baseball, Writers on Climate Change, or Writers on Their Favorite Childhood Games that really catch my eye. Writers, after all, are whole people, with varied lives and interests. When they offer up their thoughts and opinions on everything from nature to fashion to pop music to cookingâ€"in the form of beautiful and thought-provoking essays, I count it as a gift. Here are three incredible essay anthologies Ive enjoyed recently, in which a whopping total of 51 writers share their insight on three very different topics: race, rereading books, and not having kids. Selfish, Shallow Self-Absorbed: Sixteen Writers on the Decision Not to Have Kids, edited by Meghan Daum Essays (and nonfiction books of all kinds) about pregnancy, childbirth, and parenthood are not hard to find. It is hard to find the opposite: books about people who have chosen not to have kids. Being childless by choice, especially for women, is still looked upon with concern, confusion, and sometimes outright hostility. In these brilliant, moving, funny, and thoughtful essays, sixteen writers delve right into that taboo. With honesty and heart, they discuss their reasons for choosing not to have children. What I love most about this collection is the wide diversity of experience these writers represent. Some of them agonized over the decision; some knew since childhood that they did not want to be parents. Some of the essays are deeply personal; others explore the cultural idea that motherhood=womanhood, and how this is damaging for everyone. As someone who has always felt ambivalent toward motherhood, the kinship and familiarity I felt reading these essays was a refreshing change. I could not put this book down. Rereadings: Seventeen Writers Revisit Books They Love, edited by Anne Fadiman I fell in love Ex Libris, Anne Faidmans ode to books, when I first read it in high school. Rereadings, in which an array of adult writers reread books they loved as children or teens, is just as lovely. The essays vary widelyâ€"some leaning more toward literary criticism and some toward more personal narrativeâ€"but all of them capture the profundity of the impact certain books can have on our lives. Whether discussing Pride and Prejudice or the lyrics on the back of Sgt. Pepper, these essays are all delightful, insightful, and moving in their own way. This is a book about reading, but more than that, its a book about how we change over the course of our lives, using books as lens to track and explore those changes. The Fire This Time: A New Generation Speaks About Race, edited by Jesmyn Ward With essays from such literary giants as Claudia Rankine and  Edwidge Danticat (among many others), this is a must-read anthology for everyone striving to understand Americas past and present. Conceived as a response to Baldwins classic 1963 The Fire Next Time, these moving and powerful essays explore race and racism through the varying perspectives and experiences of their authors. As a whole, the collection speaks both to the trauma caused by American racism and to the possibility of a more hopeful future. I found myself copying down copious passages as I was reading it; its one of those books that Ive come back to again and again. Sign up for True Story to receive nonfiction news, new releases, and must-read forthcoming titles. Thank you for signing up! Keep an eye on your inbox.

Thegn - Anglo-Saxon Thegn or Thane

In Anglo-Saxon England, a thegn was a lord who held his land directly from the king in return for military service in time of war. Thegns could earn their titles and lands or inherit them. Initially, the thegn ranked below all other Anglo-Saxon nobility; however, with the proliferation of thegns came a subdivision of the class. There were kings thegns, who held certain privileges and answered only to the king, and inferior thegns that served other thegns or bishops. By a law of Ethelred II, the 12 senior thegns of any given hundred acted as a judicial committee that determined whether or not a suspect should be officially accused of a crime. This was evidently a very early precursor to the modern grand jury. The power of thegns declined after the Norman Conquest ​when lords of the new regime took control of most lands in England. The term ​thane persisted in Scotland until the 1400s in reference to a hereditary tenant of the crown who did not serve in the military. Alternate Spellings: thane Example: King Ethylgrihn called on his thegns to help defend against a Viking invasion.

Chemical Structures Starting with the Letter X

Vitruvian Man Lab Report - 1868 Words

Research Question: Do we have the ideal proportion? The length of the outspread arms is equal to the height of a man The distance from the elbow to the tip of the hand is a quarter of the height of the man The maximum width of the shoulders is a quarter of the height of a man Data Collection: Raw Data: Table #1: Measure of the Outspread Arm, Height, from Elbow to the Tip of the Fingers, and Width of Shoulders (cm) (per person) Name Outspread arm /cm +/-1 Height /cm +/- 1 From the elbow to the tip of the fingers /cm +/- 1 Width of shoulders /cm +/-1 Silvana Chumaceiro 170 163 43 43 Anna Marrone 165 163 41 42 Sabrina Casilla 158 156 37 54 Alberto Gonzalez 180 174 48 65 Yanuara Ramirez 164 164 41 42†¦show more content†¦The difference is about to 4 cm, which is an extremely small difference, since the maximum of her shoulders is about 39 cm and the  ¼ of her height is about 43 cm. Evaluation: Due to the fact that the Da Vinci’s Vitruvian man lab demonstrated failure on the past examinations, we can feel free to assume that many errors are shown in this experiment. The first error noticed is the fact that we measured everything with a small measuring tape instead of a big measuring tape, which didn’t help since we were taller and bigger than the measuring tape, so we had to use two measuring tapes added together. Using a small measuring tape to find out these measurements ended being extremely inaccurate. After data collection we were not really sure if the numbers we got were real, and it probably affected a lot on the way the results came out. The lab activity validity started to be questionable now. By the time we were looking for the four measurements needed just one group of people from the class was using a measuring tape, the rest of the class were using two small ones (so they could have the same length). The way it worked was to put one i n the top of the other and then add the numbers, which was hard for

Elisa and Antibody free essay sample

(1) Direct ELISAs involve attachment of the antigen to the solid phase, followed by an enzyme-labeled antibody. This type of assay generally makes measurement of crude samples difficult, since contaminating proteins compete for plastic binding sites. Indirect ELISA (2) Indirect ELISAs also involve attachment of the antigen to a solid phase, but in this case, the primary antibody is not labeled. An enzyme-conjugated secondary antibody, directed at the first antibody, is then added. This format is used most often to detect specific antibodies in sera. Competitive ELISA (3) The third type of ELISA is the Competition Assay, which involves the simultaneous addition of competing antibodies or proteins. The decrease in signal of samples where the second antibody or protein is added gives a highly specific result. Sandwich ELISA (4) The last type of assay is the sandwich ELISA. Sandwich ELISAs involve attachment of a capture antibody to a solid phase support. Samples containing known or unknown antigen are then added in a matrix or buffer that will minimize attachment to the solid phase. An enzyme-labeled antibody is then added for detection. The ELISA method is a benchmark for quantitation of pathological antigens and there are indeed many variations to this method. ELISAs are adaptable to high-throughput screening because results are rapid, consistent and relatively easy to analyze. The best results have been obtained with the sandwich format, utilizing highly purified, prematched capture and detector antibodies. The resulting signal provides data which is very sensitive and highly specific. Detailed information of specified ELISA types: Indirect ELISA, conventional but efficient Figure of Indirect ELISA Indirect ELISA is a two-step ELISA which involves two binding process of primary antibody and labeled secondary antibody. The primary antibody is incubated with the antigen followed by the incubation with the secondary antibody. However, this may lead to nonspecific signals because of cross-reaction that the secondary antibody may bring about. 1. Micro-well plates are incubated with antigens, washed up and blocked with BSA. 2. Samples with antibodies are added and washed. 3. Enzyme linked secondary antibody are added and washed. 4. A substrate is added, and enzymes on the antibody elicit a chromogenic or fluorescent signal. Â » Learn more about indirect ELISA protocol Indirect ELISA advantages : High sensitivity: More than one labeled antibody is bound per antigen molecule; Flexible: Different primary detection antibodies can be used with a single labeled secondary antibody; Cost-saving: Fewer labeled antibodies are required. In the indirect ELISA test, the sample antibody is sandwiched between the antigen coated on the plate and an enzyme-labeled, anti-species globulin conjugate. The addition of an enzyme substrate-chromogen reagent causes color to develop. This color is directly proportional to the amount of bound sample antibody. The more antibody present in the sample, the stronger the color development in the test wells. This format of indirect ELISA is suitable for determining total antibody level in samples (Newcastle disease virus, B. abortus, etc. ). Detailed information about indirect ELISA application in the determination of antibody titer and procedures of antibody concentration determination are discussed in the following section of ELISA applications. Direct ELISA, Simple and Time-Saving Initially in a direct ELISA test which is considered to be the simplest type of ELISA the antigen is adsorbed to a plastic plate, then an excess of another protein (normally bovine serum albumin) is added to block all the other binding sites. While an enzyme is linked to an antibody in a separate reaction, the enzyme-antibody complex is applied to adsorb to the antigen. After excess enzyme-antibody complex is washed off, enzyme-antibody bound to antigen is left. By adding in the enzymes substrate, the enzyme is detected illustrating the signal of the antigen. However, in terms of direct ELISA versus indirect ELISA, in an indirect ELISA, the steps are similar, but with important differences and an additional step. After the antigen is adsorbed to the plate (and after the BSA step), the next antibody to be added is the antibody that recognizes the antigen (this antibody does not have the enzyme attached to it). Then, an enzyme-antibody conjugate is prepared, which is added to the plate and detects the antibody that is adsorbed to the antigen (in a direct ELISA, the enzyme-antibody conjugate directly adsorbs to the antigen), then the substrate is added which detects the presence of the enzyme and thus the antigen. So, in the indirect ELISA, the enzyme-antibody conjugate uses an antibody against the type of antibody that is used to detect the antigen, kind of like a sandwich. For instance, if the antigen is HIV-1 gp120, then an anti-HIV antibody (HIV-1 gp120 Antibody) is prepared (lets say from a mouse). Then, in a separate reaction, an enzyme is attached to an anti-mouse antibody. So, in order to detect the HIV in the assay, an anti-mouse antibody is used to detect the antibody attached to the antigen. Direct ELISA SchematicIndirect ELISA Schematic Direct ELISA SchemaIndirect ELISA Schema Direct ELISA, when compared to other forms of ELISA testing, is performed faster because only one antibody is being used and fewer steps are required. This can be used to test specific antibody-to-antigen reactions, and helps to eliminate cross-reactivity between other antibodies. Disadvantages of direct ELISA The primary antibody must be labeled individually, which can be time-consuming and inflexible when performing multiple experiments. Also, the signal is less amplified in direct ELISA, which means a lower sensitivity and could be viewed as a disadvantage to some. Direct ELISA protocol is shown elsewhere. Please click direct ELISA appllication in monoclonal antibody screening to get more information. Competitive ELISA: Basic Principles The central event of competitive ELISA is a competitive binding process executed by original antigen (sample antigen) and add-in antigen. The procedures of competitive ELISA are different in some respects compared with Indirect ELISA, Sandwich ELISA and Direct ELISA. A simplized procedure list is as follow: Primary antibody (unlabeled) is incubated with sample antigen. Antibody-antigen complexes are then added to 96-well plates which are pre-coated with the same antigen. Unbound antibody is removed by washing the plate. (The more antigen in the sample, the less antibody will be able to bind to the antigen in the well, hence competition. ) The secondary antibody that is specific to the primary antibody and conjugated with an enzyme is added. A substrate is added, and remaining enzymes elicit a chromogenic or fluorescent signal. For competitive ELISA, the higher the sample antigen concentration, the weaker the eventual signal. The major advantage of a competitive ELISA is the ability to use crude or impure samples and still selectively bind any antigen that may be present. (Note that some competitive ELISA kits include enzyme-linked antigen rather than enzyme-linked antibody. The labeled antigen competes for primary antibody binding sites with your sample antigen (unlabeled). The more antigen in the sample the less labeled antigen is retained in the well and the weaker the signal). It is common that the antigen is not first positioned in the well. Competitive ELISA advantages: High specificity, since two antibodies are used the antigen/analyte is specifically captured and detected Suitable for complex samples, since the antigen does not require purification prior to measurement Flexibility and sensitivity, since both direct and indirect detection methods can be used Sandwich ELISA, Highly Sensitive Sandwich ELISA is a less common variant of ELISA, but is highly efficient in sample antigen detection. Moreover, many commercial ELISA pair sets are built on this sanwich ELISA. The sandwich ELISA quantify antigens between two layers of antibodies (i. e. capture and detection antibody). The antigen to be measured must contain at least two antigenic epitope capable of binding to antibody, since at least two antibodies act in the sandwich. Either monoclonal or polyclonal antibodies can be used as the capture and detection antibodies in Sandwich ELISA systems. Monoclonal antibodies recognize a single epitope that allows fine detection and quantification of small differences in antigen. A polyclonal is often used as the capture antibody to pull down as much of the antigen as possible. The advantage of Sandwich ELISA is that the sample does not have to be purified before analysis, and the assay can be very sensitive (up to 2 to 5 times more sensitive than direct or indirect ELISA), but lower than ELISpot. Sandwich ELISA procedures can be difficult to optimize and tested match pair antibodies should be used. This ensures the antibodies are detecting different epitopes on the target protein so they do not interfere with the other antibody binding. The steps are as follows: Prepare a surface to which a known quantity of capture antibody is bound. Block any nonspecific binding sites on the surface. Apply the antigen-containing sample to the plate. Wash the plate, so that unbound antigen is removed. A specific antibody is added, and binds to antigen (hence the sandwich: the Ag is stuck between two antibodies); Apply enzyme-linked secondary antibodies as detection antibodies that also bind specifically to the antibodys Fc region (non-specific). Wash the plate, so that the unbound antibody-enzyme conjugates are removed. Apply a chemical that is converted by the enzyme into a color or fluorescent or electrochemical signal. Measure the absorbency or fluorescence or electrochemical signal (e. g. , current) of the plate wells to determine the presence and quantity of antigen. The image at the bottom includes the use of a secondary antibody conjugated to an enzyme, though, in the technical sense, this is not necessary if the primary antibody is conjugated to an enzyme. However, use of a secondary-antibody conjugate avoids the expensive process of creating enzyme-linked antibodies for every antigen one might want to detect. By using an enzyme-linked antibody that binds the Fc region of other antibodies, this same enzyme-linked antibody can be used in a variety of situations. Without the first layer of capture antibody, any proteins in the sample (including serum proteins) may competitively adsorb to the plate surface, lowering the quantity of antigen immobilized. Use of the purified specific antibody to attach the antigen to the plastic eliminates a need to purify the antigen from complicated mixtures before the measurement, simplifying the assay, and increasing the specificity and the sensitivity of the assay. Sandwich ELISA Sandwich ELISA Schematic Procedure: (1) Plate is coated with a capture antibody; (2) sample is added, and any antigen present binds to capture antibody; (3) detecting antibody is added, and binds to antigen; (4) enzyme-linked secondary antibody is added, and binds to detecting antibody; (5) substrate is added, and is converted by enzyme to detectable form. Sandwich ELISA advantages: High specificity, since two antibodies are used the antigen/analyte is specifically captured and detected Suitable for complex samples, since the antigen does not require purification prior to measurement Flexibility and sensitivity, since both direct and indirect detection methods can be used Sandwich ELISA Protocol is shown in a different section. Sandwich ELISA is a common tool to diagnose Influenza, e. g. H5N1 (Avian Flu) Hemagglutinin ELISA kit. In addition, a description of the application of sandwich ELISA to home pregnancy test can be found here.