Enzyme-linked immunosorbent assay (ELISA) is based on the interaction of an antigen with an antibody, with one of them containing an enzyme. When an antigen-antibody complex is formed, the contents of the test tube (or cell of the tablet) change color under the influence of the enzyme. The result obtained is compared with a standard color scale and the antigen and its quantity are determined from it.
This diagnostic method is widely used in medicine to identify pathogens (especially viruses), determine the level of hormones, drugs in the blood, allergens, infectious diseases (viral hepatitis, rubella, hepatitis, cytomegaly, etc.), diseases of the immune system and malignant neoplasms.
Advantages of enzyme immunoassay compared to other types of immunodiagnostics:
1) high sensitivity of reactions - one enzyme molecule can cause significant changes in the interacting components;
2) the test material (plasma or serum) is required in a minimum quantity;
3) long-term storage of laboratory consumables for research;
4) the result can be assessed both using instruments and “by eye”;
5) it is possible to determine the amount of antigens or antibodies in the test material from the patient;
6) ease of implementation;
7) it is possible to carry out analysis using automatic analyzers;
8) profitability.
Enzyme immunoassay is carried out in several ways. The most often performed is a solid-phase (heterogeneous) enzyme-linked immunosorbent assay, which involves the use of an insoluble reagent with antigens or antibodies fixed on a solid surface. The corresponding components from the test material (antibodies or antigens) are absorbed by the solid reagent. Components that have not come into contact with such a reagent are easily removed from the plate. Alkaline phosphatase, B-galactosidase, and most often horseradish peroxidase are used as tag enzymes. The latter enzyme is available, very active and quite stable.
The hepatitis B virus antigen was first identified in a study of the blood of Australian Aborigines. This was the reason to call the antigen Australian, which has firmly settled in medical terminology.
Enzyme immunoassay is carried out in the presence of ortho-phenylenediamine and hydrogen peroxide. When they interact, a substance is formed, which is determined photometrically. To stop the enzymatic reaction, an inhibitory reagent, sulfuric acid, is used.
The result of the enzyme immunoassay is determined using spectrophotometry. In some cases (when the Australian antigen is detected), a confirmatory laboratory test is done to ensure the reliability of the results.
Strict adherence to the rules of analysis and use of reagents eliminates erroneous conclusions.
Enzyme-linked immunosorbent assay is carried out using different methods and methods. To carry out enzyme immunoassay for the diagnosis of viral hepatitis, many reagents are used.
"Sandwich method"
The test material with antigens is added to the antibodies fixed on a solid insoluble surface under certain conditions. Then, unreacted components are removed from the plate and enzyme-containing antibodies to the intended antigen are added. Next, the tablet is again kept under certain conditions and the components that have not reacted are removed. The antigen remains on the tablet, sandwiched between layers of antibodies. If antibody-antigen-antibody + enzyme complexes are present, then when a chemical substrate is added, its color changes.
ELISA methods:
1) antigens fixed on a solid surface + material from the patient with antibodies + enzyme-containing anti-antibodies (antibodies to the patient’s immunoglobulin G). Using these reagents, antibodies to the hepatitis C virus are detected;
2) antigens fixed on a solid surface + material from the patient with antibodies + enzyme-containing antigens. In this way, antibodies to the Hbs antigen are detected (Australian antigen - a sign of hepatitis B);
3) standard antigens + material from the patient with antibodies + enzyme-containing antibodies fixed on a solid surface. In this way, antibodies to antigens of hepatitis B and Dh E viruses are detected;
4) antigen fixed on a solid surface + enzyme-containing antibodies + material from the patient. Used to detect antibodies to hepatitis A, B, C viruses.
One-step "sandwich method"
This is an accelerated version of the previous analysis. In this case, the test material and enzyme-containing antibodies are added to the plate with fixed antibodies simultaneously. This simplifies the analysis and reduces its time.
Multilayer "sandwich method"
To carry out the analysis, a plate with fixed antibodies to the patient's antibodies (immunoglobulins) is used, to which material from the patient is added. It is kept under certain conditions and unreacted components are removed. Then a standard antigen is added to the wells of the plate, and after a number of reaction conditions are met, it is removed
unreacted components. Next, enzyme-containing antibodies are added to the cells. This is a more complex and time-consuming analysis than the “simple sandwich” method.
Antibodies fixed on a solid surface (antibodies to immunoglobulin M) + material from a patient with antibodies + standard antigen + enzyme-containing antibodies.
In this way, antibodies (immunoglobulins M) to hepatitis A and B viruses are detected. There are other options for enzyme-linked immunosorbent assay.
The ability to communicate with people is necessary not only for those who “work as psychologists.” Everyone seems to agree with this truth. But not everyone understands by the expression “the ability to communicate with people” what is, in my opinion, the most important thing here.
Namely: The result of your “ability to communicate with people” should always be the psychotherapeutic benefit you bring to these people. That's it.
And you should know: for communication with you to have a psychotherapeutic effect on people, you don’t have to be that same psychotherapist!
But for this, you still need to learn some proven, almost technical, methods of, so to speak, “interpersonal interaction.”
One of them, which I present to you today, is called "Sandwich Technique". It is as simple as a sandwich with butter, but not everyone knows that a lot depends on following the simple conditions of its preparation.
According to the sandwich principle, communication is built like this: the beginning and end must be positive character, and the middle includes everything negative moments (which are really necessary).
A. Start with the good.
IN. Continue to be difficult and unpleasant.
WITH. End on a good note.
It would seem that what is incomprehensible here? In theory, everything is clear. However, with practice it is more difficult. In practice, we often don’t think about the fact that communication is an art and therefore it should be built according to its own clear laws.
In practice, we are used to this. We follow two strict patterns. Or:
- We organize an evening of “unpleasant conversations”, saving up all the “unpleasant moments” for this evening for a year or month.
- We arrange a boring, unbearable routine “evening of compliments”, not allowing a “bad word” to escape our lips, and thereby further preparing the ground for the subsequent unpleasant conversation that is inevitable.
Sandwich technique This is precisely what allows us not to keep a stone in our bosom, so that later, at the most unexpected moment, we do not dump a mountain of accumulated stones on the head of an unsuspecting interlocutor.
This technique is based on the axiom: a person always has something to say to another person: both pleasant and unpleasant. Moreover, “pleasant things” need to be said twice as much. It is then that the “unpleasant” will be normally absorbed, digested and realized.
If you choose a strategy “I don’t scold anyone, I get along with everyone” , then this strategy will only work for you for the time being. And then you will lose your temper and earn a reputation as an unpredictable and unbalanced, or even two-faced person who “laid down softly”, but then had to sleep hard...
If, on the contrary, you choose the strategy “my task is to point out shortcomings, let the flatterers praise” , then they will soon simply stop listening to your negativity; you will be broadcasting into the void. This is how people absorb unpleasant noise - they stop hearing it altogether. As a result, you will also achieve nothing with your criticism.
Each act of communication should be built on the principle of a sandwich - a piece of butter between two pieces of bread - so as not to stain anything, not to leave an annoying greasy stain, but so that it is ultimately nutritious and healthy.
At first, your attempts to always act according to this principle will look somewhat artificial. But then you will get used to the sandwich rule, which will immediately affect the quality of your communication.
Moreover, people will listen to your advice and criticism, without ceasing to consider you the most sincere person from all their surroundings.
To work effectively and develop, employees need information about what they are doing that is successful and what needs to be changed. Therefore, during management training, managers learn methods of feedback to subordinates. One of the most common is the sandwich method. Managers are taught to first celebrate positive aspects of an employee's performance (praise #1), then offer criticism, and then praise again, ending the conversation on a positive note (praise #2). The “stuffing”—a critical remark—is sandwiched between two “buns” of praise. Initial praise is needed in order to build contact, gain trust, and reduce the employee’s wariness and resistance. The criticism that follows helps improve results. And the praise at the end should smooth out the unpleasant aftertaste from criticism. This is how this “fast food” should work in theory.
Research results disprove the effectiveness of the sandwich method and, worse, indicate negative side effects. Researchers asked employees how they preferred to receive feedback. And people unanimously advocated that criticism and praise should not be mixed in one conversation, but should be heard separately. Employees who regularly receive “sandwiches” begin to consider any positive comments from the manager as insincere. After all, they know that after the praise, what the manager really wanted to say will definitely be heard - criticism. But the effect of criticism is also reduced, and often completely disappears due to praise No. 2. Everyone thinks that the manager did not seriously mean that, for example, being late is unacceptable, because he praised the employee at the end of the conversation. It is known that people remember best ideas expressed at the beginning and end of a conversation.
Many managers use the sandwich method not because it is effective. It’s just easier to start a difficult conversation not with unpleasant words, but with positive ones. But the longer the laudatory opening speeches, the more difficult it is for the leader to move on to criticism.
For feedback to be effective, the manager needs to consistently solve two problems.
Build a relationship in which the employee is not indifferent to feedback from management. Such relationships are based on either trust or fear. An employee will trust a manager's feedback if he believes that the manager sincerely wants to help subordinates and is not just asserting himself, and if he believes that the manager is informed and competent in the issue under discussion.
Or relationships can be built on fear, when an employee is afraid to fail the manager’s expectations. But to do this, the employee must know that the manager has real power to reward or punish. Subordinates must make sure that it will not be possible to hide poorly done work from their superiors and that punishment (or less often, reward) will be inevitable.
However, such a relationship between an employee and a manager can be built (or destroyed) throughout the entire time they work together, and not in one specific conversation. And trying to instantly build trust with praise #1 is quite naive.
Influence employee actions using feedback. How to do this correctly from a scientific point of view? Feedback timing, the minimum interval between an event and subsequent feedback (conversation), is one of the main success factors. Therefore, annual review procedures are rarely useful in improving results. Frequent feedback, almost online, will have a much greater effect.
If an employee is already behaving correctly, he can be supported with praise. But advances and promises that encourage employees to respond correctly do not work. Let's say a manager notices that an employee is shirking work. The promised bonus for hard work will only strengthen the employee’s desire to continue doing nothing. Therefore, first you need to achieve conscientious work and only then praise his real successes.
Undesirable behavior can be corrected through constructive criticism, but it must be tied to the moment of the event being discussed. Punishing an employee after the fact, when he has already missed all the deadlines, will not help correct the situation. And criticism should not be confused with threats. For example, promising to fire an employee if he continues to shirk work will only lead to the employee avoiding contact with the manager, but will not begin to perform better.
If a manager has already built a relationship of trust and praises and criticizes subordinates with a sincere desire to help, he should do this without pause, as quickly as possible, and also express his thoughts specifically and constructively.
The problem is that there will always be employees who are not ready to hear the manager’s comments and adjust their actions. The reason is that their experiences with people in power—parents, teachers, previous bosses—have been negative and sometimes traumatic. And this skepticism may extend to you. The simple solution is to get rid of the problem employee. But it will be more useful if you take the time to build a trusting relationship and praise the employee in those seemingly insignificant situations where he heard and took into account your wishes. And then even a seemingly incorrigible employee can pleasantly surprise you.
27.11.2013 14:56
Do you occasionally use the sandwich method when giving negative feedback to subordinates? In other words, are you covering up negative comments with positive ones? In fact, this is a fairly common method that managers like to resort to. But it doesn't work. Then why is it so popular? There are several explanations for this:
Managers think that people find it easier to hear and accept negative feedback when it has a positive connotation. When I ask managers how they understand this, it turns out that for the majority this is more correct. When I ask direct reports how they would prefer to receive negative feedback, almost all admit that they want “meat instead of a sandwich,” that is, to understand the essence of the comment. So if you give sandwich feedback, you run the risk of alienating your direct reports. In addition, in this case, they tend to ignore the positive aspects, believing that there is no sincerity in them.
Managers use the sandwich method to provide balanced feedback. Such leaders want subordinates to understand negative feedback only as part of an evaluation. But this attitude doesn't stand up to scrutiny when I ask them if they feel the need to do this for themselves. Of course, positive feedback is important, but if it is used only to sweeten the pill with negative feedback, then it diminishes its value. Therefore, it is better to separate positive and negative feedback from the beginning.
Managers believe the sandwich method minimizes discomfort and anxiety. Less often, leaders admit to using the sandwich method because they are simply uncomfortable giving negative feedback and are forced to cling to positive comments. But in reality, such caution creates a feeling of anxiety among employees. The longer you talk without giving negative feedback, the more uncomfortable you are likely to make the transition, and your employees will feel uncomfortable and anxious.
In this way, the sandwich method has the ability to influence other people without having to tell them what you are doing. This is a one-way control strategy that revolves around influencing others without being influenced by them in return.
Imagine that you are planning to use the sandwich method with two direct reports, Alex and Stacy, who are making a presentation to senior management. To understand why you are reluctant to use a transparent strategy, try this test:
- Determine your strategy for the conversation. Your strategy should start with some positive feedback to relax Alex and Stacy. Then move on to negative feedback (since that is the purpose of the meeting) and end with positive comments so that employees are not too disappointed.
- When talking to people, have a strategy in mind. It's better to say something like: “Alex and Stacy, I have a number of questions for you. I want to start with some of the positives of your work and then move on to the negatives that led to this meeting being scheduled. I will end our meeting with positive comments so that you are not angry with me. What do you think about it?"
- Observe your own reaction. Doesn't it make you laugh when you expect absurdity to make your strategy more transparent? If you think you'll never be able to "say it," then you're pursuing a one-way control strategy: an attempt to control the situation without giving Alex and Stacy the opportunity to deviate from the plan. One-sided management strategies only work if other people are unaware of them or are willing to play by your rules. But such strategies are less effective.
You can use this same three-step test in any situation to evaluate your chosen strategy.
Avoid the Sandwich Method, Use Effective Transparent Strategies
Here's an example of transparent negative feedback that can empower you and your direct reports to learn:
“Alex and Stacey, I want to talk to you because there are aspects of my job that are making me anxious. The presentation you gave to senior management today may have created confusion in our strategy. Let me tell you how I imagine this meeting, I want to understand how useful it will be for you. I'll start by describing what I see and what worries me. It is important to me that we see the same thing. Once we have a shared vision of what happened, I will elaborate on the issues and listen to your views. We can then decide what we need to do next. I may have missed something or be overly concerned, so I want to know what you think about this.”
The transparent approach is much more effective than the sandwich approach for several reasons. First, by sharing your strategy and asking for Alex and Stacy's opinions, you invite them to join in the discussion, so you all learn through the experience together. Secondly, outlining the meeting sequence allows the joint efforts to direct the discussion in the right direction. Third, by being open about the possible lack of information and exaggeration of the problem, you do not limit the meeting to only your own opinion, but allow everyone to examine the problem and think about where to move next.
This reciprocal approach to learning works better, not because you say a lot of fancy words, but because you recalibrate your attitudes. This means that you view negative feedback as an opportunity to help your subordinates improve what you have not considered; consider it as a way to choose the right solution through joint efforts. Through transparent negative feedback, you show your employees that you respect them rather than control them.
Translation: Inga Hammi
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Giving someone critical feedback to suggest that the person change their behavior is a delicate matter. To avoid the common problem of defensiveness, it is important to be sure that you approach the issue with understanding and consideration for the other person's feelings.
If done correctly, the person you are approaching will perceive your opinion positively, which will naturally lead to good results! One of the most effective ways to do this is to hide the teaching technique between other positive statements, like a “sandwich.” The instructions below outline a way to do this, whether it's a challenge with friends or a parent raising a child. A similar technique, sandwich compliments, has similar steps. The sandwich feedback technique is most often used for coaching and support, while the related compliment technique aims to soften or disguise necessary criticism.
Steps
"You did a really good job in your essay 'Treat People Fairly' - it really impressed everyone! For the future, it's best not to call out those people who don't accept your whole method. It's great that you thought about everything so carefully this – you will benefit many people!”
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Compliment: Thanks for patrolling the latest changes. I'm amazed that you reviewed 400 edits today and stopped so much vandalism.
Encouragement and inspiration: Thanks again for patrolling the latest changes. You've done a great job and have really improved the quality of information on wikiHow. I sincerely hope that you will continue to make invaluable contributions to the improvement of our general knowledge.
- For effective feedback, honesty is essential. Avoid compliments in your review if you have difficulty finding positive points.
- Nevertheless.... Coaching is not a solution for every situation. The human resource management model of the 80s has been left behind by a management system more adaptable to individual characteristics, a person's experience and the pressing current problem. Sometimes coaching is the right solution, sometimes a slap on the wrist is needed, and sometimes immediate dismissal is needed. Don't use coaching as a buzzword or as a prop when something else is needed. In the wikiHow example, where the person formatted the article incorrectly, he probably needed coaching. At the same time, systematic “sabotage” with a sufficient number of preliminary warnings justifies placing a person on the ban list.
- Practice coaching regularly: If you incorporate it into your daily life, you will learn to use it more effectively, and people will gradually lose their fear of it. Try not to become obsessed with coaching, otherwise you will lose both credibility and influence.
- Practice: It's a good idea to practice in front of a mirror, or better yet, in front of another person, before using it in real life. Your task is to learn to present your position smoothly, with an even delivery,
- Constantly monitor how your feedback is received. This will allow you to make necessary changes to your approach if necessary.
- Keep a positive attitude: If you do this with a positive attitude towards the person and the situation, then your mentoring will bring good results. Moreover, a negative attitude is guaranteed to ruin your entire venture.
- Do not use this technique repeatedly for the same reason: When you are discussing with a person a particularly serious problem or a situation that has already been discussed with him, this technique will not be effective - you need a more direct approach.
- Don't act condescending: You are trying to change behavior. There is no need to demonstrate your superiority, do not be indignant, do not behave pretentiously - this is guaranteed to destroy the attempt to establish communication.
- During the educational process, you should not limit yourself to only positive feedback: If you start showering compliments while using the “sandwich” technique, the person will become embarrassed and begin to wonder what he did wrong.
- Give sincere, personalized compliments: People will notice if you are patronizing - your intentions will become obvious and the technique will be less likely to succeed.
- Avoid Blame: You are simply pointing to something that needs change. What circumstances led to this does not matter. What is important is what is happening at the moment, how the situation will develop, and how you will achieve these results. Overall conversation must pass on positive emotions. Of course, there will be an unpleasant part, but the two positive ones will outweigh it. Leave your interlocutor in high spirits, and you will get the results you seek.
- Be sincere: Much has been said about being unyielding, but remember that when you change the way you express your criticism, it may sound completely different. Be realistic and always push for behavior change. Remember that you need to change beliefs, and not just behavior, as their external manifestation; By changing your beliefs, you will encourage behavior to change.
Prepare: Don't rush into a situation without first and carefully thinking and planning. A good plan is a tool for success. Without it, you can easily get off track and lose control of the conversation. You must be clear about what you want to say and how you want to say it.
Praise – identify positive points: Find something meaningful among this person's actions. It should be somehow related to the educational technique (coaching technique) that you are planning to conduct, and be in the recent past. For example, if all the white clothes in the washing machine turned pink because of the red shirt that person threw in there, the phrase “I really appreciate you helping me with the laundry!" can be a conversation starter.
Conduct an educational technique - present the facts: Now you have captured the person’s attention and have positioned him to perceive your words. Pause to let this feeling sink in, then move straight into coaching. Avoid words "But" And "but next time" because they provoke the person to become defensive, which is exactly what you are trying to avoid. Speak directly and firmly, but never allow yourself to become angry or humiliating. Communication is a science, so if you want to achieve positive results, you must behave in a scientific. "Let me teach you how to sort clothes so we don't have to deal with a bunch of pink socks anymore.""
Encourage and inspire - give a favorable forecast: When you conduct a coaching session, a person inevitably feels a little empty. Do not leave communication at this point - such an unpleasant phenomenon must be eliminated quickly but correctly. Mention the positive outcome of future attempts. The logical conclusion would be that the person has laid the foundation for a successful start (primary praise), and there are ways to improve this foundation (coaching), and the combination of these elements will produce excellent results (encouragement and inspiration). “It’s great to have another pair of hands to help, we’ll all have more time for afternoon video game fights!"
Come back to this point later: You don’t have to wait until the problem reappears to check for changes in behavior; express friendly curiosity and helpfulness, and continue to push the person to change. The goal is the anchor of the positive nature of changes in human consciousness. If you leave the situation unattended, your teaching moment may be forgotten. Without constant reinforcement, the process of “extinction” begins – the desired changes in behavior will never occur.
Example of sandwich feedback from wikiHow
Here's an example of sandwich feedback: The kind of response that could have been given on a wikiHow talk page.
