Chinese name of blockchain
The strict definition of blockchain refers to the distributed database technology that multiple nodes in peer-to-peer network jointly maintain a continuously growing list ledger constructed by time stamp and orderly record data blocks through consensus mechanism based on cryptography technology. This technical solution allows any number of nodes in the participating system to calculate and record all the information exchange data in the system in a period of time to a data block through cryptography algorithm, and generate the fingerprint of the data block for linking the next data block and checking. All participating nodes in the system jointly determine whether the record is true
blockchain is a technical solution similar to NoSQL (non relational database). It is not a specific technology, and can be implemented through many programming languages and architectures. There are many ways to realize blockchain, including pow (proof of work), POS (proof of stake), dpos (delegate proof of stake), etc
the concept of blockchain was first proposed in the paper "bitcoin: a peer-to-peer electronic cash system" by indivials (or groups) who call themselves Satoshi Nakamoto. Therefore, bitcoin can be regarded as the first application of blockchain in the field of financial payment
< H2 > [popular explanation]no matter how big the system or how small the website is, there is a database behind it. So who will maintain this database? In general, who is responsible for the operation of the network or system, then who is responsible for the maintenance. If it is wechat database, it must be maintained by Tencent team, and Taobao database is maintained by Alibaba team. We must think that this way is natural, but blockchain technology is not
if we think of the database as a book, for example, Alipay is a typical account book. Any change of data is bookkeeping. We can think of database maintenance as a very simple way of accounting. In the world of blockchain, everyone in the blockchain system has the opportunity to participate in bookkeeping. The system will select the fastest and best bookkeeper in a period of time, maybe within ten seconds or ten minutes. The bookkeeper will record the changes of the database and the account book in a block. We can think of this block as a page. After the system confirms that the records are correct, the system will record the changes of the database and the account book in a block, It will link the fingerprint of the past account book to this paper, and then send this paper to everyone else in the whole system. Then, over and over again, the system will look for the next person with fast and good bookkeeping, and everyone else in the system will get a of the whole ledger. This means that everyone as like as two peas in the system is called Blockchain. It is also called distributed account technology. P>
as like as two peas (computer) have identical accounting books, and everyone has the same rights, they will not collapse e to the loss of contact or downtime of a single person. As like as two peas, the data is transparent and everyone can see what changes are in every account. Its very interesting feature is that the data can't be tampered with. Because the system will automatically compare, it will think that the same number of books with the largest number are real books, and a small number of books with different numbers are false books. In this case, it's meaningless for anyone to tamper with his own account book, because unless you can tamper with most nodes in the whole system. If there are only five or ten nodes in the whole system, it may be easy to do so. However, if there are tens of thousands or even hundreds of thousands of nodes and they are distributed in any corner of the Internet, unless someone can control most computers in the world, it is unlikely to tamper with such a large block chain
< H2 > [elements]combined with the definition of blockchain, we think that we must have the following four elements to be called public blockchain technology. If we only have the first three elements, we will consider it as private blockchain Technology (private chain)
1, peer-to-peer network (power equivalence, physical point-to-point connection)
2, verifiable data structure (verifiable PKC system, non tampering database)
3, distributed consensus mechanism (Solving Byzantine general problem, solving double payment)
4 Game design of Nash equilibrium (cooperation is the strategy of evolutionary stability)
combined with the definition of blockchain, blockchain will realize four main characteristics: decentralized, trustless, collective maintenance and reliable database. And the other two will be derived from the four characteristics Features: open source Privacy. If a system does not have these characteristics, it can not be regarded as an application based on blockchain technology
Decentralized: there is no centralized hardware or management organization in the whole network. The rights and obligations of any node are equal, and the damage or loss of any node will not affect the operation of the whole system. Therefore, it can also be considered that the blockchain system has excellent robustnesstrustworthiness: there is no need to trust each other when participating in the data exchange between each node in the whole system. The operation rules of the whole system are open and transparent, and all data contents are also open. Therefore, within the specified rule range and time range of the system, nodes cannot and cannot cheat other nodes
collective maintenance: the data blocks in the system are maintained by all the nodes with maintenance function in the whole system, and these nodes with maintenance function can be participated by anyone
reliable database: the whole system will enable each participating node to obtain a of the complete database in the form of sub databases. Unless more than 51% of the nodes in the whole system can be controlled at the same time, the modification of the database on a single node is invalid, and the data content on other nodes cannot be affected. Therefore, the more nodes and computing power in the system, the higher the data security in the system
Open Source: since the operation rules of the whole system must be open and transparent, the whole system must be open source for the program
Privacy Protection: since there is no need to trust each other between nodes, there is no need to disclose the identity between nodes, and the privacy of each participating node in the system is protected
Link
< H2 > 1. Introctionlink is the erc20 standardized token based on Ethereum blockchain, which is used to pay the chainlink node operators, so as to retrieve data from the data of the chain off, format the data into the readable format of the blockchain, calculate the chain off and ensure the normal running time. Chainlink token, as a part of the running node, can prevent undesirable participants
< H2 > 2. Project introctionthe first distributed Oracle network, which allows anyone to safely provide smart contracts, access key external data, offline payment and any other API functions. Any user with a data feed, offline service (such as local payment) or any other API can directly provide it to a smart contract in exchange for a link token. Chainlink network is a distributed network of chainlink nodes, which directly transport specific data, API and various offline payment functions to smart contracts. Chainlink network is composed of two independent parts, on chain and off chain, which must interact to provide services. The network is built in such a way that it can be upgraded, so that it can replace its different components when better technologies and technologies emerge. The chain components of the network filter Oracle through service level agreement (SLA) based on the measurement of one party's request of smart contract. Using these metrics, chainlink collects responses to SLA queries, sorts them using reputation and aggregation models, and provides final set results of chainlink queries that may be implemented in smart contracts. The out of chain components of the network are composed of Oracle nodes connected to the Ethereum network, which independently collect responses to offline requests. These off link nodes can be located in any instry. For example, the off link nodes operated by the New York stock exchange can provide real-time and accurate transaction information for the chainlink network, or the off link nodes of the visa network can solve transactions and interact with consumers and suppliers through the chainlink network. Chainlink technology aims to integrate nodes from all these instries into a common network, which itself acts as a (low-cost) middleman, interpreting and allocating data correctly as needed. The chainlink system will ensure that the results obtained from the Oracle are accurate and allow the oracle to remain independent of the data they provide. Any data, payment, e-signature or other API providers and personal developers can easily join the chainlink network by connecting their familiar API to the network. Once the API is connected to the chainlink, the user becomes the chainlink node operator and is responsible for connecting the API to the chainlink network. In order to motivate operators to provide API information, they are compensated in the link token to successfully complete the online link request. The project currently provides a fully distributed Oracle network compatible with bitcoin, Ethereum and hyperledger. It is expected that other blockchains will be supported in the future, which will allow cross chain connections between smart contracts and any other public or private chains, and allow anyone in the world to use the chainlink network, regardless of its platform. All service providers will be able to securely provide smart contracts to access critical external data and possibly even non chained payments
< H2 > 3. Commentchainlink (link) is a decentralized network, which can provide information (Oracle) for smart contracts. Chainlink was established by Sergey Nazarov and Steve Ellis in 2017, aiming to solve the problem of information procurement under the chain through smart contract for its execution parameters. Smart contract is designed to execute automatically when some parameters are satisfied. However, when these parameters exist under the chain, it depends on the information source (called Oracle) to provide the necessary information. Off chain predictors are often centralized and rely on third parties to provide critical information in a reliable and time-consuming manner. Chainlink aims to break this dependence by providing information to smart contracts through a decentralized prediction network. These predictions work together on the link blockchain to verify and forward key information to these contracts. Chainlink network allows users with data feeds or information hosting APIs to easily provide information to smart contracts in exchange for link tokens< memorabilia September 2017 - chainlink ICO. November 2018 - acquisition of town crier (smart contract and data privacy project). June 13, 2019 - announced cooperation with Google utility link network to provide timely and accurate information to smart contracts through Oracle's distributed network (data sources and APIs). This information is very important for the effective and accurate execution of smart contracts, because the required information exists under the chain, and there must be a reliable way to obtain the information on the chain. The link token is used as payment for smart contracts that use the data provided by the link network, in which the oracle that provides accurate information will be rewarded in proportion to the link< important functions partnership with major instry players such as swift and Google, integration of Ethereum side chain, such as harmony, celer and matic. Average block time n / A; The total supply is 1 billion link; Write Oracle consensus to Ethereum blockchain through threshold signature
related links: https://chain.link/
https://en.bitcoinwiki.org/wiki/ChainLink
https://everipedia.org/wiki/lang_ en/chainlink-cryptocurrency
https://blog.chain.link/threshold-signatures-in-chainlink/
https://blockonomi.com/chainlink-guide/
7. CTnI bedside testing (POCT)
7. What is POCT
POCT is the abbreviation of point of care testing in English, which refers to the clinical testing carried out beside patients. It's not always the clinical laboratory. The main standard of POCT is that it doesn't need a fixed testing place, the reagents and instruments are portable and can be operated in time. POCT does not need special clinical testing services< The main purpose of POCT is to get the experimental results more quickly. The progress of diagnosis and auxiliary technology, the understanding of the disease and the improvement of treatment level are the main reasons for POCT to get more attention (financial pressure is the secondary factor). These advances have brought some diseases close to eradication and others to early diagnosis and better treatment
for the diagnosis of AMI patients, if the clinical manifestation is highly suspicious and the ECG manifestation is not decisive, the application of cTnI bedside diagnostic reagent can make it easier and more accurate for the diagnosis and treatment of AMI patients. The whole process takes only 15 minutes
7,2,2 are easy to use
and easy to use. POCT has become a part of the diagnosis system because of its ease of use; POCT takes on the function of laboratory without traditional hospital laboratory equipment. POCT can be done in a doctor's clinic or in a moving car. POCT can provide all-round service for patients 24 hours without the limitation of time and place
7,2,3 save comprehensive cost
the biggest problem faced by laboratory personnel is to control the cost of diagnosis. But the results always rece the cost of a single test, but not the cost of the whole process. In terms of "single inspection cost", POCT is relatively high; But in many cases, the application of POCT can not only improve the experimental results, but also rece the occupation of resources (hospitalization time, sampling time, medical staff occupation time, etc.)< 7, 3ctni POCT (bedside diagnosis) in the diagnosis of cardiovascular disease
cardiovascular disease is the largest potential killer of alts in the western world. In the United States alone, more than 70 million people suffer from heart disease every year, and about 6 million people go to the emergency room every year because of chest pain, of which 2.5 million patients are acute coronary syndrome (ACS), Among them, there are 1.5 million patients with acute myocardial infarction (AML) and 1 million patients with unstable angina pectoris. The annual mortality rate of acute myocardial infarction is more than 500000. That is to say, only 1 / 4 of the patients with chest pain are really threatened by AML, while other patients with chest pain do not need further treatment in the hospital, If it is impossible to confirm whether patients with chest pain suffer from fatal AMI in a short period of time, those non AMI patients will not only have to worry without reason, but also have to bear extra large medical expenses and hospitalization expenses every day. Not only that, some patients with AMI were delayed or even died because of the delayed diagnosis and treatment
cTnI POCT can make the AMI patients who really need treatment get treatment in time with fast and correct diagnosis, shorten the patients' medical treatment time, on the other hand, it can rece the social medical cost, rece the expenditure of those patients who do not need further treatment, release the unnecessary medical occupation of the society, and enable the hospital to treat more patients.