2023 Dodge Ram Tyrannosaurus Rex Rebel 480,000 from the end of the clearance price.

The 2023 Dodge Ram Tyrannosaurus Rex in Tianjin Port is now sold in the sixth country, and it is licensed nationwide. The 23 Dodge Ram Tyrannosaurus Rex uses a supercharged 6.2-liter HEMI? HELLCAT V8 engine with a maximum horsepower of 712 horsepower and a maximum torque of 881 Nm. Ram 1500 TRX has become the fastest and most powerful mass-produced half-ton pickup truck in the world. In terms of torque, TRX provides a new performance level with a speed of 0 to 100 km/h in 4.9 seconds and a top speed of 190 km/h.

  

Configuration: limited edition of TRX ignition (MoparTRX ignition decal, TRX special edition central control logo, 18-inch wheels, orange decorative stitching, pedestrian emergency braking, leather and carbon flat-bottomed steering wheel, carbon fiber interior, Mopar container telescopic pedal, Mopar4-way adjustable cargo binding hook, adaptive cruise with start and stop, double-window panoramic sunroof, lane keeping aid, and bottom two-color car paint. Mopar embedded container liner) TRX 2 package (leather trimmed bucket seat, front seat ventilation, wrapped main driver’s assistant armrest, luxurious front door panel decoration, full-length advanced upgraded center console, lift display, digital rearview mirror, advanced wrapped instrument panel, LED ambient light, radio/main driver’s seat/mirror/pedal memory function, main driver’s seat memory, 4-way electric lumbar support passenger seat, 8-way electric main driver and passenger. Electric adjustable pedal includes memory function, pedal lighting, traction braking management, Harman Kardon advanced audio includes 19 speakers, blind spot and intersection detection, front seat heating, second seat heating, steering wheel heating, parking assistance before and after parking induction includes stop function, cargo box lighting, rain sensing front windshield wiper, rear seat bottom storage box, electric tailgate, rear 60/40 folding seat, Mopar cross-country style pedal, and traction reverse steering control.

The exterior design of the Dodge Ram Tyrannosaurus Rex has a strong sense of impact. Compared with the well-behaved family design, the front of the Dodge Ram Tyrannosaurus Rex is undoubtedly a little more aggressive to the road. The eyes do not reveal a trace of lively charm, and the only thing that is displayed is fierceness. The front bumper is an iron front bumper with a hook, which exudes a metallic atmosphere and is calm and atmospheric. As the best-selling model, it has a very aggressive front face. Dodge Ram Tyrannosaurus Rex has completely got rid of the rough feeling of the United States. The edges and seams are carefully handled. The leather seats are independent and equipped with comfortable functions such as heating and massage. Each seat is equipped with a control handle independently, and each function is controlled by the rider himself. All seats of Dodge Ram pickup truck are wrapped in leather, and the front row is also equipped with very practical sports seats.

 The design of the 2023 Dodge Ram Tyrannosaurus Rex center console is simple and hard, which conforms to the temperament of the ram. The bottom of the dashboard has patterns, which further highlights the elegance of this car. The soft instrument panel design is very comfortable to the touch, and there is nothing stiff.

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The chassis of 23 Dodge Tyrannosaurus Rex has also been greatly upgraded. The chassis is made of a large number of high-strength steel to improve the rigidity of the frame. At the same time, the suspension system is also equipped with an adaptive shock absorber from Bilstein, which can reduce the vibration during high-speed desert driving and off-road, and improve driving performance and durability.

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The interior of the 23 Dodge Tyrannosaurus Rex is simple and generous, but this will not affect its luxurious texture. The rich configuration will make you admire it. At the same time, as the flagship model of the Dodge family, the new car is also equipped with a 12-inch vertical central control screen. In addition to supporting common functions such as Bluetooth, navigation and car Wi-Fi, it also supports Apple CarPlay and Android Auto phones.

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In addition to its powerful power, the performance version of the 23 Dodge Ram Tyrannosaurus Rex is also first-class in off-road performance. The clearance between the vehicle and the floor is 28cm, the contact angle is 30.2, the departure angle is 23.5, the passing angle is 21.9, and the wading height is 81.28cm, which can correspond to most sections. In addition, the new car is equipped with an adaptive shock absorber from Bilstein, and the stroke of the front and rear wheels reaches 33.

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The electronic image of the answer sheet for visiting the 2019 college entrance examination marking site can be saved for 4 years.

  Yesterday, Jiangsu Education Examinations Institute held an open day for marking the college entrance examination. Yangzi Evening News reporter and 12 candidates and parents’ representatives from Nanjing came to the marking site of the college entrance examination, visited the answer sheet storage group, scanning group and Chinese subject marking group successively, and got in touch with the marking work of the college entrance examination at zero distance, feeling the fair, just, rigorous and orderly working atmosphere of the marking of the college entrance examination.

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  The electronic image of each candidate’s answer sheet is kept for 4 years.

  At the examination paper scanning point of the Provincial Education Examinations Institute, the staff are busy unpacking and scanning the examination paper, storing the information in the warehouse, and scanning it through a high-speed special scanner, cutting the contents of the examination paper into pictures, encrypting the candidates’ names, admission ticket numbers and other information, and sending them directly to each marking point through special optical fiber.

  Fu Yaozhang, director of the Network Information Center of the Provincial Education Examinations Institute, said, "The scanning number of all answer sheets in all subjects must be consistent with the data of candidates participating in the arrangement, and the electronic image of each candidate’s answer sheet should be kept for 4 years."

  As in previous years, this year, all subjects of the college entrance examination in our province will continue to carry out computer-aided online marking, and the Provincial Education Examinations Institute will undertake the scanning of answer sheets and the marking of multiple-choice questions. For non-multiple-choice questions, the marking of Chinese, mathematics and foreign languages will be handled by Nanjing Normal University, and the marking of six selected subjects and small languages will be handled by Nanjing University.

  Wu Renlin, vice president of the Provincial Education Examinations Institute, said that there were more than 2,200 marking teachers this year, all of whom were selected from the database of marking teachers in the province. Among them, the marking teachers who mark the test questions with large scores and strong subjectivity, such as composition questions, discussion questions, calculation and solution questions, experiments, etc., all have more than 3 years of teaching and research experience and some marking experience.

  "Four-evaluation system" makes marking more fair

  The marking method is also particular: the "four-evaluation system" is implemented in the non-multiple-choice part of all subjects. "After the test paper is scanned and entered into the computer, it will be cut into several blocks. After cutting, the computer will automatically process all the blocks with secret numbers. All the secret numbers correspond to the candidates one by one, but the marking teacher can’t see any identity information of the candidates, and no one can change the answer sheets after secret number processing, which can ensure the fairness and justice of marking work." Wu Renlin said that each marking group marked the cut blocks separately, and each block was randomly distributed to two different marking teachers for independent marking. If the scores scored by the two people are within the scoring threshold set by the subject marking expert group, the average of the scores scored by the two people is taken; If it exceeds the scoring threshold, it will be submitted to the third marking teacher for three evaluations; If it still exceeds the scoring threshold, it will be submitted to the fourth marking teacher for four evaluations. The difficult problems encountered in the marking process are collectively discussed and solved by the marking expert group.

  Marking progress

  Chinese: the score of the test questions is accurate to 1 point.

  Professor Cao, a member of the Chinese marking group of the college entrance examination, introduced that this year’s marking was more orderly, rigorous, scientific and stable. On the second day after the end of the college entrance examination, marking experts entered the marking site to prepare for marking. At present, the scores of most topics are accurate to 1 point, ensuring that the hard work of each candidate is properly reflected.

  Professor Cao said that the marking of Chinese in the college entrance examination has maintained a steady and progressive trend. "This year, the Chinese in the college entrance examination is generally stable. From the results of the trial evaluation, it is easier for candidates to get started, and their thoughts and feelings can be expressed, and the degree of discrimination in the test papers is ideal. For the composition evaluation that candidates and parents care about, we will focus on correcting the phenomenon of high scores and low scores in the process of marking and correcting ‘ False and wrong cases ’ Strictly check the excellent composition and carefully identify the fake phenomenon of low scores and high scores. In addition, the team leader and the staff of the expert group will repeatedly check without any dead ends, and organize the verification team to conduct spot checks on the composition marking. "

  Mathematics: More than 8 solutions have been prepared for each problem such as function.

  The math marking team for college entrance examination consists of math teachers from NTU and NTU and more than 80 middle school teachers. Professor Yan, a member of the math marking group and professor of Nanjing Normal University, introduced that the math marking group organized a subject expert group and each topic leader to investigate the answers of the province’s math test papers, and learned about the possible answers of candidates through full investigation. "The expert group has been carefully formulating the scoring rules. For example, function problems and many big problems have provided more than eight solutions, so it is necessary to formulate scientific evaluation criteria. Decompose each solution into knowledge points, and ensure that homogeneous knowledge points give the same scores and fair standards. Once a new solution is found, the marking teacher must report to the subject expert group in time, and then the experts will discuss and study the scoring rules of this solution, and they are not allowed to evaluate it privately. "

  Professor Yan revealed that the mathematics marking of the college entrance examination should be completed before the 20th.

  English: enrich the grading rules and take care of a variety of reasonable composition viewpoints and angles.

  Professor Shao, a member of the English marking group, introduced that the expert group carefully analyzed the characteristics and reference answers of "task-based reading" and "written expression" and refined the evaluation criteria; The writing points and sub-points of the composition part are subdivided. At the same time, through a large number of sample papers covering various regions and examination rooms, starting from the actual situation of candidates’ answers, the scoring rules are enriched and a variety of reasonable composition viewpoints and angles are taken care of.

  English marking implements a three-level quality monitoring system of subject expert group, marking team leader and team members. Each paper has been reviewed by team members for multiple rounds back to back, arbitrated or spot-checked by team leader, and monitored and spot-checked by experts. At the same time, the online marking system and monitoring system have a clear division of labor. According to the characteristics of English subjects, the software is designed scientifically and matched reasonably, and equipped with real-time marking, quality statistics, bad error monitoring and early warning systems to avoid misjudgment as much as possible.

  Yangzi Evening News/Yangyan reporter Yang Tianzi

The direct economic loss was more than 14.57 billion yuan, and Zhejiang agriculture quickly resumed self-help after the disaster.

  China Rural Network News (Reporter Jiang Wenlong, Zhu Haiyang) The landing of super typhoon "Likima" has had a great impact on Zhejiang’s economy. According to the latest statistics, as of 8: 00 on the 11th, the affected area of crops in Zhejiang Province was 173,000 hectares, with a total harvest of about 22,000 hectares, 34,000 houses damaged due to the disaster, and the direct economic loss was more than 14.57 billion yuan. At present, the Zhejiang Provincial Department of Agriculture and Rural Affairs has issued a notice, demanding that all efforts be made to resume agricultural production after the typhoon.

  Previously, Zhejiang has released agricultural disaster prevention and mitigation technical measures such as planting, animal husbandry and fishery. In order to effectively strengthen the guidance service and strengthen the implementation of technical measures, all parts of Zhejiang are coordinating relevant forces, selecting a group of people with familiar business and excellent skills to form a disaster relief guidance group, and rushing to the scene at the first time to investigate and understand the disaster situation, visit and sympathize with the affected farmers and agricultural production and operation entities, and help solve practical difficulties in agricultural production.

  Zhejiang requires that all localities should use seeds, pesticides, fertilizers, disinfectants, vaccines and other reserve materials in time according to the disaster situation and demand, coordinate and organize the transfer of agricultural production materials between regions in time, and give priority to ensuring the supply of agricultural disaster relief materials. If the affected fields need to replant vegetables and other crops, it is necessary to coordinate and organize relevant seedling enterprises, pay close attention to breeding, and do a good job in docking seedlings.

  The reporter learned that local agricultural disaster relief guidance groups have gone to the front line of disaster relief. On the 10th, technicians from Yueqing Agriculture and Rural Bureau went to Nanyue Egg Duck Breeding Community to guide the post-disaster recovery work, and went to the fields of farmers insured by policy agricultural insurance to check the disaster situation. Technicians from Deqing County Agricultural and Rural Bureau visited agricultural producers such as aquatic products, orchards and shrimp farming to survey and guide the response of agricultural typhoon prevention; Agricultural technicians from Xiangshan County Agriculture and Rural Bureau went to Dingtang Town Elemental Egg Duck Breeding Base and Shipu Town Grape Planting Base to provide guidance on post-disaster recovery.

  The reporter learned that the typhoon node was special and had a great impact on fishery production in Zhejiang. Zhejiang Fishery Mutual Insurance Association has organized forces to rush to the disaster-stricken sites all over the province for the first time to collect survey information and statistics on damage data. Pacify members’ anxiety, and do a good job in claims settlement and service in post-disaster fishing areas. On the evening of the 9th, the Provincial Institute of Marine Fisheries dispatched 15 experts overnight to form a disaster relief expert guidance group, especially for Yueqing and Dongtou, which were seriously affected by the disaster, to visit and inspect the relevant breeding and seedling raising bases and enterprises on the spot, and to assist the local agricultural and rural departments to carry out disaster relief technical guidance. (Photo by: Zhejiang Provincial Department of Agriculture and Rural Affairs)

Seeing consumption at the beginning of the year | Fixing the most beautiful family photo studio appointment before the holiday is hot.

CCTV News:The Spring Festival is coming, and it is the choice of many families to take family photos in the photo studio. The reporter recently visited the Beijing market and found that the passenger flow of many photo studios has increased significantly, and some places even have to make an appointment many days in advance.

Reporter:I am now in Dabei photo studio on Qianmen Street in Beijing. The staff told me that with the approach of the Spring Festival, more and more customers come here to take photos, especially the family photos are selling more and more hot.

Beijing consumers:Once a year, I added this family of five, and I took my parents with me. It was also the first time to take a photo with my baby.

Beijing consumers:Want to take a picture of her (mother) every year, (she) is a little nervous.

In the photo studio, the staff told reporters that in recent days, family photos, black and white and color headshots are still the main products in the store, and most customers are coming from this classic nostalgia.

Beijing consumers:We were born in the 1980s, and there weren’t many color photos at the beginning. It’s quite retro to bring children to take pictures.

Meng Qingyi, manager of Beijing Dabei Photography Front Store:At the end of the year, the passenger flow still increased. Usually, we take more than 200 photos (every day), but now we can take between 300 and 400 photos, mainly because we have more photos.

Reporter:Different from the traditional photo studio, we see more young people in this fast and fashionable photo studio in Xidan, Beijing. For them, taking a photo at the end of the year is the pursuit of a sense of ritual in life.

Beijing consumers:We want to shoot something academic, or something related to the New Year.

Beijing consumers:This suit is also suitable for the occasion, just in line with the new year atmosphere.

The reporter learned that with the continuation of Christmas and New Year’s products and the launch of family photo products in the Spring Festival, there are more choices of products in the photo studio at present. The price of a single person ranges from 300 to 500, and the daily reception volume has also increased by about 20% compared with usual.

Wang Xinwei, manager of a fast fashion photo studio in Beijing:Many customers choose to take a photo at the festival just to increase the sense of ceremony and send a circle of friends. Basically, every day is a full state, and weekends are full. The best sellers are Weiyang and Chiying in the national tide. Because it is red and Chinese style, customers will have more choices.

Ru Zhengang, the maker of "anti-fate wheat": what you want all your life is a bumper harvest.

Image source: China Radio Network

Image source: China Radio Network

CCTV News:"Family, less idle month, people twice as busy in June. At night, the south wind rises and the wheat is covered with yellow. " It’s the wheat harvest season in a year. Under the blue sky in the distance, golden wheat waves are surging. The newly harvested wheat is ground into fragrant flour and enters the kitchens of various households. ……

One out of every eight steamed buns eaten by more than 1.3 billion people in China comes from the wheat variety "Bainong Aikang 58", which is known as "the first wheat in Huanghuai". It is "Mai Da" Ru Zhengang who successfully cultivated this new wheat variety. He is the vice president of the School of Life Science and Technology of Henan University of Science and Technology, the director of the Henan Hybrid Wheat Engineering Technology Research Center, and the chief expert of wheat disease and pest resistance breeding in Henan Province.

Ru Zhengang often said: "As an agricultural science and technology worker, you can’t help farmers increase production and income. You are nothing!" His lifelong aspiration is to fill the granary of China with the power of science and technology.

Change the world with a "go against the sky wheat seed"

Food is scarce and farming is difficult. These childhood memories make Ru Zhengang have an indescribable feeling for wheat. He has always had a "wheat dream", "We must have enough food in Chinese, and the granary is full of our own wheat".

In 1981, Ru Zhengang, who graduated from agronomy, was selected by Professor Huang Guangzheng, a national expert who was famous in the breeding field at that time and won the second prize of national invention, and "pulled into" the breeding industry. Since then, it has been persistent for 36 years.

In order to find the root of the problem of wheat growth, Ru Zhengang ate and lived in the wheat field for several days. In order to ensure the accuracy of the data, he took the research team to manually thresh one by one; In order to understand the growth of wheat in various places, he traveled almost every wheat producing area in China.

In the process of breeding new wheat varieties such as "Aikang 58", Ru Zhengang explored and created a set of nearly complete scientific methods, theoretical systems and scientific research equipment and breeding platform established from it. In his breeding base, from the molecular biology laboratory to the artificial climate room, to the intelligent greenhouse, and then to the outdoor experimental field, it takes only a few minutes to be fully prepared. It is these few minutes’ path that shortens the time of wheat breeding by six years.

Ruzhengang successively cultivated and popularized many varieties such as "Bainong 62", "Bainong 64", "Bainong 160" and "Bainong Aikang 58", and the wheat varieties with stable and high yield filled the granaries of China, which also made the people happy. Ruzhengang has become an out-and-out "God of Grain".

The inspiration for scientific research propositions comes from ordinary people.

"All my scientific research topics and the inspiration and source of technological innovation come from ordinary people." Ru Zhengang traveled all over the country in most wheat fields, and no matter where he went, he never forgot to ask the villagers to "find fault" with their own seeds.

Can wheat be high-yielding and lodging-resistant? Can wheat be planted whenever it wants? The ears of wheat are big, can you make more grains? There are too many ears, can you make the straw shorter? The wheat straw is short, can it tolerate barren and drought? … … Seemingly harsh problems are thrown at him from time to time, and if Ru Zhengang gets the treasure, it will eventually turn into his most breakthrough and creative scientific research topic.

Many experts believe that the wheat yield in Huanghuai area of China has reached the "ceiling", and it is "even more difficult" to further increase the yield. Ru Zhengang’s thoughts and vision jumped to the northeast and Guangdong, Fujian and other places, hoping to find a record-breaking "artifact" in these places.

He constantly challenges himself and his limits. "Even though the frost of time has stained my temples and the knife of years has carved my forehead, why don’t I change my mind and be as heroic as yesterday?" Ru Zhengang expressed his ambition to charge for hybrid wheat breeding in poetic language.

Loving wheat is like your own daughter.

Ru Zhengang said that after 36 years of research, Wheat is actually like his daughter. It can understand his words, and he knows how it can be good, what it likes, what it doesn’t like, and how to make it happy.

"When you chat with wheat with your heart, you can feel the power of its life. Although the breeding work has to face failure 90% of the time, every improvement is an exploration of life and a spiritual enjoyment." Ru Zhengang said.

In Ru Zhengang’s view, wheat that can give people full returns, like wheat, is not wheat, but wheat of a work of art.. He wants to cultivate better wheat varieties, serve the strategic needs of modern agricultural production and national food security, and make new contributions to China’s food security and agricultural harvest. (Source: Ministry of Science and Technology)

On the Writing Skills of Patent Application Documents in China National Intellectual Property Administration Public Welfare Lecture

  In practice, a large number of inventions are protected by submitting patent applications and obtaining authorization. Therefore, the writing quality of patent application documents often affects whether the patentee can successfully defend his rights and resist competitors. In this paper, the author discusses the writing skills of patent application documents from the perspective of writing patent application documents.

  First, we should consider the appropriate scope of protection. The so-called "appropriate" scope of protection refers to obtaining as large a scope of protection as possible on the premise of complying with China’s patent law and its implementation rules.

  The author thinks that a patent application document can "predict" the comparison documents that may be retrieved, which is based on the full retrieval of domestic and foreign patent documents in the early stage of writing the patent application document, so as to determine the appropriate level of existing technology, construct an appropriate scope of protection, and make the patent more stable.

  In practice, the author found that many existing patent application documents only describe the technical scheme itself. The author believes that the process of writing patent application documents is a process of secondary creation, which requires the joint participation of inventors and patent agents to discuss various implementation methods to solve the technical problems involved in invention-creation, and determine the claims after summarizing and abstracting the technical characteristics of the implementation methods (upper generalization or functional limitation). And the upper generalization also needs as many examples as possible so that the claims can be supported by the specification. When judging the infringement, the functional features are interpreted as the specific embodiment disclosed in the specification and its equivalent embodiment, and the application of the equivalence rule is easy to have objections. Therefore, it is helpful to obtain a more appropriate scope of protection by excavating as many embodiments as possible in the writing stage of patent application documents.

  Second, when writing patent application documents, we should also consider it from the perspective of being conducive to infringement judgment. For example, based on principle of universal coverage, when writing the patent application file at first, only the most necessary technical feature set that can solve the technical problems of the invention needs to be written into the independent claim, and unnecessary technical features will only limit the narrowing of the protection scope. In practice, the name of the invention, the characteristics of the use environment, the technical characteristics of the product defined by the preparation method, and the step sequence of the method claim may limit the scope of patent protection, so it should be carefully considered when using it. If there are possibly ambiguous terms in the claim and they are not explained in the specification, it may cause obstacles to the interpretation of the subsequent claims.

  Third, the commercial prospects of patented products or methods should be considered. In the writing stage of patent application documents, patent agents may find that technical solutions can be applied to fields with more commercial prospects during the communication with inventors. For example, a technical scheme can be used in PC, but after understanding the existing technology, it is found that its application prospect in mobile terminal is very considerable, but it needs to be adjusted accordingly when applied in mobile terminal, so different technical schemes are produced, and the application strategy needs to be adjusted in time.

  Fourth, we should consider whether patents can be easily evaded by competitors. The patent agent can work with the applicant to develop possible improved technical solutions and possible deteriorated technical solutions. The improved technical solutions can be used as a "retreat" in the patent examination stage and may prevent competitors from submitting improved solutions to patent applications. According to the Guide to Determining Patent Infringement issued by Beijing Higher People’s Court, the deteriorated technical scheme does not constitute equivalent infringement, so the deteriorated technical scheme should also be considered when writing patent application documents.

  Fifth, it should be considered that it is conducive to obtaining evidence and safeguarding rights. If the applicant is engaged in the production of products, from the perspective of tort compensation, it may be more beneficial for the right holder to write patent application documents mainly against product manufacturers. This is because it is generally easier for sellers, importers and users of infringing products to prove the legal source of infringing products. In this case, it is advantageous to write the product and the claim of the preparation method of the product.

  In the fields of communication, network and computer, the applicant may face multiple infringing objects, and which infringing objects he hopes to resist is an important factor in determining his claim. Different claims can be designed for different infringing objects.

  Generally speaking, it is more beneficial to obtain evidence if you can know the technical characteristics of the product without disassembling it or using it by consumers. If you need reverse engineering to determine whether a product is infringing, you need to consider the difficulty of reverse engineering. For example, for related patents in the chemical field, the technical features that can be measured by ordinary measuring instruments or technologies are more conducive to obtaining evidence. For patents related to semiconductor and chip fields, if reverse engineering is easy to realize, components and their connection modes can be described. If reverse engineering is difficult to realize or the cost is high, it is necessary to consider whether it is necessary to change the writing method.

  Sixth, we should consider the layout strategy. When writing patent application documents, we should also pay attention to the role of dependent claims, that is, in addition to independent claims, other novel and creative technical features can be arranged in dependent claims to prevent competitors from evading design.

  At the same time, different levels of protection scope should be considered, and some patent application documents may be incompatible with certain technical features. At this time, independent claims with different protection scope can be considered to avoid giving up some protection scope due to modification. In addition, in some cases, the protection scope of the method claim can be different from that of the product claim, for example, the protection scope of the method claim can be greater than that of the product claim to achieve different levels of protection.

  Chinese applicants need to consider the relevant laws and regulations of different countries when writing patent application documents if they want to arrange patents abroad. When submitting an international patent application through the Patent Cooperation Treaty (PCT), due to the relatively limited space for modification, it is especially necessary to strictly check the priority documents.

  For example, when filing an American patent application, we should avoid too much self-admission and discussion about the existing technology. Because the U.S. Patent and Trademark Office has a strict review of Antecedent Basis, patent Enablement and Written Description, it should be extra cautious when writing priority documents. (Li Xingdi only represents the author’s personal views)
 

Notice on printing and distributing the vaccination work plan to deal with the recent infection situation in Covid-19

Notice on printing and distributing the vaccination work plan to deal with the recent infection situation in Covid-19
Guo Wei Ming Dian [2023] No.46

All provinces, autonomous regions, municipalities directly under the Central Government and Xinjiang Production and Construction Corps should respond to the joint prevention and control mechanism (leading group and headquarters) of novel coronavirus infection, and the State Council should respond to the members of the vaccination coordination group of the joint prevention and control mechanism of novel coronavirus infection:

The "Work Plan for Vaccination in Response to Recent Infections in Covid-19" is hereby printed and distributed to you, please conscientiously implement it according to the actual situation.

The State Council responds to novel coronavirus infection.Comprehensive group of epidemic prevention and control mechanism
April 6, 2023

(Information disclosure form: voluntary disclosure)

Respond to the recent Covid-19 infection epidemic.Vaccination work plan

In order to thoroughly implement the decision-making arrangements of the CPC Central Committee and the State Council, effectively respond to the recent epidemic situation in Covid-19, and ensure and safeguard people’s health, this work plan is formulated in combination with the epidemic situation, vaccine research and development, immune effect evaluation, population immunity level and other factors.

First, the target population

At this stage, the focus of vaccination is to fill the gap in immune level for different target groups and further reduce the risk of severe illness and death. The target population is as follows:

(a) people who are not infected and have not completed the established immunization program. Including uninfected people aged 3-17 who have not completed basic immunization, uninfected people aged over 18 who have not completed the first dose of booster immunization, and uninfected people aged over 18 who have not completed the second dose of booster immunization (high-risk people with infection, elderly people over 60 years old, people with serious basic diseases and people with low immunity).

(two) people who have been infected and have not completed basic immunization.

Second, the time interval and vaccine selection

(1) Time interval.

The uninfected target population completes the follow-up vaccination according to the established immunization program and its time interval requirements. Among them, for people over 18 who have completed basic immunization, the interval of the first dose of booster immunization is adjusted to more than 3 months.

People who have been infected and have not completed basic immunization can be vaccinated with one dose after 3 months of infection.

(2) vaccine selection.

Shenzhou cell recombinant Covid-19 tetravalent S trimer protein vaccine and Unacon Covid-19 mRNA vaccine have been included in emergency use, which can be used for intensive immunization of people over 18 years old.

The vaccines used for basic immunization of uninfected target population shall be implemented with reference to the relevant requirements in the previous period. In order to strengthen immunization, it is recommended to use Shenzhou cell recombinant Covid-19 tetravalent S trimer protein vaccine and Unacon Covid-19 mRNA vaccine. Other recombinant protein vaccines or virus vector vaccines that have been approved for conditional marketing or emergency use can also be selected for sequential enhanced immunization.

People over the age of 18 who have been infected and have not completed basic immunization are recommended to use Shenzhou cell recombinant Covid-19 tetravalent S trimer protein vaccine and Unacon Covid-19 mRNA vaccine, or choose other recombinant protein vaccines or virus vector vaccines that have been approved for conditional marketing or emergency use. For people aged 3-17 who have been infected and have not completed basic immunization, the vaccines used for vaccination shall be implemented according to the relevant requirements of the previous period.

Follow-up will be based on the progress of vaccine research and development, approval, combined with the epidemic situation, virus variation and other conditions, timely research and adjustment of vaccination strategies.

Third, ensure vaccination safety

All localities should continue to give priority to vaccination safety, and organize vaccination implementation in strict accordance with the requirements of the Code for Vaccination Work. Local health departments should implement the "four haves" requirement that vaccination units should have emergency personnel stationed in general hospitals at or above the second level, emergency equipment and medicines, 120 ambulances on duty, and green channels for treatment in general hospitals at or above the second level to ensure vaccination safety. Inoculation units should do a good job in vaccination information registration and vaccine flow management, and update the vaccination records in the immunization planning information system and vaccination vouchers in a timely and accurate manner.

Fourth, strengthen organization and implementation

(1) Strengthening the responsibility of territorial subjects. All localities should implement the responsibility of territorial management, attach great importance to and co-ordinate the vaccination work in Covid-19. It is necessary to strengthen the guidance of vaccination work within the jurisdiction and fully grasp the progress of the work. Relevant local departments should strengthen docking and do a good job of coordination.

(two) to play the role of the competent department of industry. The competent departments of relevant industries should guide the units where the personnel in this industry work to actively cooperate with local unified arrangements and jointly do a good job in organizing and mobilizing.

(3) Strengthen supervision and guidance. It is necessary to closely track and monitor the progress of vaccination in various places, and find and study and solve related problems in time. Improve the traceability system of vaccine flow, improve the safety supervision mechanism of vaccine chain, continuously strengthen the whole process management and safety precautions, and effectively ensure the efficient and smooth transportation of vaccines.

(4) Do a good job in publicity and guidance. All localities and relevant departments should, according to the needs of work, formulate targeted publicity measures for vaccination work, focus on the purpose and significance of vaccination, respond to social concerns, sum up and popularize typical experiences and practices, actively guide the target population to take the initiative to vaccinate, and especially guide and improve the vaccination rate of the elderly population.

Note: People aged 3-17 can only use Covid-19 inactivated vaccine of Sinopharm Zhongsheng Beijing Company, Beijing Kexing Company, Sinopharm Zhongsheng Wuhan Company and Zhifeilong Kema recombinant Covid-19 vaccine (CHO cells).

National CDC: In September, 879,567 cases of legal infectious diseases were reported nationwide, with 2,213 deaths.

  CCTV News:According to WeChat official account, the National Bureau of Disease Control and Prevention, on October 23rd, the National Bureau of Disease Control and Prevention released the national epidemic situation of legal infectious diseases in September 2023:

  In September 2023 (from 0: 00 on September 1st to 24: 00 on September 30th), 879,567 cases of legal infectious diseases were reported in China (excluding Hongkong, Macao Special Administrative Region and Taiwan Province, the same below), with 2,213 deaths.

  Nine cases of Class A infectious diseases were reported, all of which were cholera, and no deaths were reported.

  Among the Class B infectious diseases, except novel coronavirus infection, 304,210 cases were reported and 2,213 people died, including SARS, poliomyelitis, human infection with highly pathogenic avian influenza, diphtheria and human infection with H7N9 avian influenza. The top five reported diseases are viral hepatitis, tuberculosis, syphilis, gonorrhea and dengue fever, accounting for 92.7% of the total reported cases of Class B infectious diseases.

  In the same period, a total of 575,348 cases of Class C infectious diseases were reported, and no deaths were reported. The top three reported diseases are influenza, hand-foot-mouth disease and acute hemorrhagic conjunctivitis, accounting for 80.2% of the total reported cases of Class C infectious diseases.

Members of the North Korean leader’s family set foot in South Korea for the first time. Kim Jong-un’s sister’s resume is extraordinary

  CCTV News:South Korean Presidential Palace Cheongwadae announced on the 8th that Moon Jae in will meet with a visiting high-level delegation from the DPRK on the 10th. Members of the delegation include Jin Yongnan, Chairman of the Standing Committee of the Supreme People’s Assembly of the DPRK, Jin Yuzheng, First Deputy Minister of the Central Committee of the Workers’ Party of Korea, Cui Hui, Chairman of the State Sports Steering Committee, and Li Shanquan, Chairman of the Peaceful Reunification Committee of the Motherland. According to Xinhua News Agency, the DPRK delegation arrived at Incheon Airport in South Korea by special plane at noon on the 9th.

  Who’s Jin Yuzheng? What is the future trend of the situation on the peninsula? Will the representatives of North Korea, South Korea and the United States interact outside of sports events? The PyeongChang Winter Olympics in 2018 was full of topics before it started.

  Rare! Kim Jong-un once only took his twin sister to inspect the troops.

  Jin Yuzheng is the daughter of the late North Korean leader Kim Jong Il and the younger sister of Kim Jong Un.

  On March 9, 2014, Jin Yuzheng made her first "official appearance" in a report on North Korean national television. At that time, Kim Jong-un was elected as the representative of Baitoushan Constituency No.111 with 100% support rate. Jin Yuzheng, known as "Comrade", appeared for the first time in the report, and a "close-up" of her voting was shown.

  On November 27th, 2014, Kim Jong-un inspected the 426 Animation Studio. Korean Central News Agency mentioned Jin Yuzheng, Vice Minister of the Central Committee of the Labor Party, when introducing the accompanying personnel. This was the first time that the North Korean media publicized Jin Yuzheng’s position, which attracted the attention of foreign media.

  After that, Jin Yuzheng can always be seen in Kim Jong-un’s activities reported by North Korea’s official media. From watching performances, to inspecting factories and museums, to inspecting military training activities, Jin Yuzheng’s name can always be found in the list of accompanying persons.

  From March 9, 2014 to March 12, 2015, Jin Yuzheng accompanied Kim Jong-un on 25 inspections. Since November, 2014, Jin Yuzheng has been accompanying Kim Jong-un to inspect more and more frequently, accounting for more than half of the total times. Generally speaking, Jin Yuzheng’s people’s livelihood and cultural performances are twice as many as her military and political visits. However, since November 2014, her visits to the army have been basically the same as other activities. In January 2015, Jin Yuzheng’s public activities were particularly active, and he accompanied Kim Jong-un on seven inspections.

  On March 12, 2015, Kim Jong-un, the top leader of North Korea, visited a defense squadron in the front post on the east coast of North Korea. In Korean Central News Agency’s report, only the name of Kim Jong-un’s sister Jin Yuzheng was mentioned, but the names of other accompanying persons were not mentioned. Judging from the pictures released by the Workers’ Party of Korea, Jin Yuzheng not only accompanied Kim Jong-un to inspect the whole process, but also participated in the final photo. This kind of situation is rare. Usually, the entourage of Kim Jong-un does not take part in the group photo during the inspection activities, and it is the first time that only Kim Jong-un’s brother and sister inspect the troops in the official media of North Korea.

  At present, it is a critical moment for the DPRK and the ROK to release goodwill and improve bilateral relations. Kim Jong-un sent Jin Yuzheng to represent North Korea in the opening ceremony of the PyeongChang Winter Olympics, and the position of the younger sister in North Korea’s political arena is self-evident.

  The South Korean side also attaches great importance to the first entry of North Korean Kim family members into Korea. A spokesman for South Korea’s Cheongwadae said that all preparations would be made to ensure the smooth visit of the DPRK high-level delegation to South Korea to participate in the Olympic Games, and called Jin Yuzheng’s visit "of great significance". As Jin Yuzheng is an important figure in the Labor Party, the ROK expects that she will have considerable discretion in this trip, which is more important than Jin Yongnan’s coming to hankyung alone, and the ROK and the DPRK may take this opportunity to have a more meaningful dialogue.

  The close interaction between the DPRK and the ROK, the United States and Japan secretly "make bad"

  The 23rd Winter Olympics in Pyeongchang, South Korea in 2018 is destined to be an "unusual" Winter Olympics. Before that, the Vice President of the United States invited "special guests" to pour cold water on the relations between the DPRK and the ROK, and then members of the North Korean "Baitoushan family" (Kim family) entered Korea for the first time. During this period, it was reported that Trump’s daughter would attend the closing ceremony of the Winter Olympics and the South Korean Unification Ministry made intensive statements four times in three days … … The "feature film" of the 2018 Winter Olympics has not yet started, and the "trailer" alone is as wonderful as any Hollywood movie.

  At the beginning of the new year in 2018, the DPRK and the ROK changed the normal state of "arrogance" and "angry words", shelved the dispute between nuclear weapons and Sadr, and launched active "ice-breaking" talks around the Winter Olympics in a "double pause" posture, which achieved many results. For example, the DPRK and the ROK will jointly hold the flag of the Korean Peninsula at the opening ceremony of the Winter Olympics, the Korean art troupe will perform the opening ceremony in South Korea, and the DPRK and the ROK have expressed their positive will to improve the bilateral relations in the future … …

  At the same time of close interaction between the DPRK and the ROK, the United States began to "pour cold water" on the slowly warming DPRK-ROK relations.

  US President Donald Trump confirmed last month that he would send Vice President Burns as the head of the US delegation to attend the PyeongChang Winter Olympics. However, it is not known what attitude Burns will take to intervene in the situation on the Korean Peninsula. A White House official said that Burns believed that the DPRK wanted to use the Winter Olympics to "engage in propaganda activities" and he intended to "show up" at the Winter Olympics to "offset" the DPRK’s influence and self-promotion efforts.

  According to Washington post, Burns will invite a "special guest", namely Fred, the father of the late American college student Otto Warmbier, to visit Korea. Otto Warmbier was charged and convicted of conspiring to subvert the state in North Korea, and was detained for more than a year. He was released to China in June last year, but he was in a coma and died a few days later. This incident once prompted the State Council to issue a travel ban to the DPRK.

  It is also reported that US President Trump’s daughter ivanka will lead a presidential delegation to attend the closing ceremony of the 2018 PyeongChang Winter Olympics. Some South Korean media analysts said that if ivanka really attended the closing ceremony of PyeongChang Winter Olympics as reported by CNN, and Kim Jong-un’s younger sister Jin Yuzheng also went south for a pre-meeting, it might be possible for them to meet in the closing ceremony of Winter Olympics.

  The DPRK, the United States and South Korea are playing hot, and Japan is also joining in the fun. According to the news released by the Japanese government on the 3rd, Prime Minister Shinzo Abe will meet with Burns before attending the opening ceremony of the Winter Olympics, suggesting that the US-South Korea joint military exercise should not be scaled down after the Winter Olympics.

  … …

  The Korean Peninsula crisis has lasted for more than 20 years, and the biggest obstacle is the "return to Asia-Pacific strategy" of the United States. However, this "door-to-door talk" between the DPRK and the ROK is a sincere attempt by the DPRK. It is hoped that with the efforts of all parties, the stability of the DPRK and the ROK will be further developed, and the rare "warm drama" between the DPRK and the ROK will not become a "farce" with no end in some countries. (Text/Cheng Xiang)

It’s urgent, the reason of false negative in COVID-19 nucleic acid test and its countermeasures!

Author: Hongge comes from Medical Wechat WeChat official account.

        Recent epidemic situation in ChinaIn the process of getting up, there are some situations that deserve our attention.the most importantIsFalse negatives in nucleic acid detection. Intercepting relevant news, it was found that 8 confirmed patients in Shijiazhuang on the 22nd were repeatedly negative for nucleic acid detection, and 5 confirmed patients in Shijiazhuang on the 24th were repeatedly negative for nucleic acid detection.


   On the 22nd, there were 11 new confirmed cases in Shijiazhuang, including:

Case 1: Male, 52 years old, from Huangjiazhuang Village. On the evening of 21st.Ninth nucleic acid positive;

Case 2: Male, 13 years old, Niujiazhuang Village. On the evening of the 21st.Nine times nucleic acid positive;

Case 3: Female, 11 years old, Zhongyao Village. On the evening of the 21st.Nine times nucleic acid positive;

Case 4: Male, 49 years old, Nanqiaozhai Village. On the evening of 21st.Ninth nucleic acid positive;

Case 5: Male, 47 years old, Niujiazhuang Village. On the evening of 21st.Ninth nucleic acid positive;

Case 6: Female, 65 years old, Niujiazhuang Village. On the evening of 21st.Ninth nucleic acid positive;

Case 7: Male, 11 years old, grandson of Case 6. On the evening of 21st.Ninth nucleic acid positive;

Case 11: Male, 67 years old, Xiaoguozhuang Village, husband of Case 2 on January 7th. On January 3, it was transferred to centralized isolation medical observation; On the evening of 21st.11th nucleic acid detectionFinally positive;

On the 24th, there were 7 new confirmed cases in Shijiazhuang:

Case 1: Female, 65 years old, Nanqiaozhai Village. Centralized isolation on the 11 th.Nucleic acid after 9 times, 22 positive.

Case 2: Female, 4 years old, Nanqiaozhai Village. Centralized isolation on the 11 th.Nucleic acid after 9 times, 22 positive.

Case 3: Female, 4 years old, Mi Jie, Chang ‘an District. Centralized isolation on the 13 th.Nucleic acid after 8 times, 23 positive.

Case 4: Female, 64 years old, Xiaoguozhuang Village. Centralized isolation on the 10 th.After 11 nucleic acids, 24 positive.

Case 5: Male, 34 years old, Xiaoguozhuang Village. Centralized isolation on the 8 th.After 11 nucleic acids, 24 positive.

Case 6: 34-year-old female, Liujiazuo Village, was positive for nucleic acid on the 5th, was diagnosed as asymptomatic infection on the 6th, and was clinically confirmed on the 24th.

Case 7: A 28-year-old male, living in Yuhua District, went to work by car at Zhengding Airport on weekdays. He was diagnosed as asymptomatic infected with nucleic acid on the 5th, and was clinically confirmed on the 24th.


Since the outbreak of COVID-19 last year, the topic of high false negative rate of nucleic acid detection has been the focus of attention. It has been reported that the positive rate of Covid-19 detection by fluorescence quantitative RT-PCR is only 30%-50% at present, which leads to extremely high false negative rate.

For Hongge, who doesn’t know much about the test, this paper analyzes the relatively high false negative test by searching articles and documents, and summarizes some reasons to discuss with you.

First, the incidence of COVID-19 suggests that it is highly possible to collect positive samples in a proper time.

Academician Yuan Guoyong’s team conducted this cohort study in Hong Kong Princess Margaret Hospital and Queen Mary Hospital. From January 22 to February 12, 2020, 23 hospitalized patients who were diagnosed as COVID-19 by laboratory examination of nasopharyngeal or sputum specimens were screened in the two hospitals.

A total of 173 respiratory specimens were collected from 23 patients. The researchers used RT-QCPR to determine the viral load in the samples. The results showed that the median viral load of respiratory tract samples was 5.2 log10 copies /mL (interquartile range was 4.1-7.0), and only 3 patients (13%) did not detect Covid-19 RNA in saliva samples.

The researchers observed that,The viral load in saliva was the highest in the first week after the patient developed symptoms, and then gradually decreased.Eight days after the patient developed symptoms, airway extracts were collected, and there was no obvious downward trend in viral load. Of the 21 patients who did not die,Seven people (33%) could still detect viral RNA after 20 days of symptoms, but this was not related to the severity of the disease.

▲ Changes of viral load in saliva (blue line) and airway extract (red line) of all 23 patients. Abscissa D- days after symptoms appear; S/E- number of saliva/airway samples.

AprilAccording to a study published in Nature Medicine, COVID-19 patients are most infectious before symptoms appear, and they begin to shed SARS-CoV-2 2 2-3 days before the first symptoms appear.

https://doi.org/10.1038/s41591-020-0869-5

The study, led by Eric Lau of the University of Hong Kong, involved 94 patients with COVID-19 admitted to the Eighth People’s Hospital of Guangzhou, China, 50% of whom were male, with a median age of 47 years. Among them, 61 of 93 patients were mild. Specifically, the researchers collected the throat swabs of 94 COVID-19 patients who were treated in the Eighth People’s Hospital of Guangzhou, China from January 21st to February 14th. From the onset of symptoms to 23 days after onset, 414 throat swabs were collected.

The results show that the researchers areThe high viral load was detected shortly after the patient developed symptoms, and then gradually decreased to the detection limit around the 21st day.There is no significant difference in viral load among different sexes, age groups and disease severity.

In addition, the researchers also analyzed 77 samples of "transmission pairs" from public data to assess how much time passed between the onset of symptoms in each patient. It assumes that the median incubation period (the time from infection to symptoms) is 5.2 days.The research team concluded that infectivity began 2.3 days before symptoms appeared, and peaked 0.7 days before symptoms appeared.

In the sensitivity analysis, the same estimation procedure is used, but assuming that the infectious attack is unchanged 1-7 days before the symptom occurs, thenIt was found that the infectivity reached its peak 0-2 days before the onset of symptoms, and the transmission ratio before the onset of symptoms was 46% to 55%.

The study also found that,The virus may start shedding 2-3 days before the first symptoms appear.After the symptoms appear, the viral load in the patient’s body decreases faster. This is consistent with the results of two recent studies. On April 1st, teams from Munich, Germany, Berlin and Cambridge, England published the article "Viro logical assessment of hospital patients with Covid-2019" on Nature. It was found that the shedding peak of Covid-19 occurred in the early upper respiratory tract infection.This shows that virus carriers may be the most infectious when they have mild symptoms or almost no obvious symptoms.

Brother Hong:From the above two documents, we can draw a conclusion that the virus shed and spread 2-3 days before the symptoms appear after infection, and after the symptoms appear, with the passage of time,The viral load of throat swab decreases gradually, and the viral load detected within 7 days after symptoms. If symptoms have existed for more than 20 days, the reliability of negative conclusion of throat swab is poor.

Solution:We need to publicize the law of the new crown to the people and medical workers, and improve our vigilance against COVID-19. It is best for patients to see a doctor in time, and doctors can also suspect this possibility. Only at the right time can we collect high-content samples and diagnose and control them in time.

Second, accurate sampling strategy is the best means to reduce false negative results.

In February, a study published by Medrxir, a pre-printed website, collected respiratory tract samples such as nasal swab, throat swab, sputum and bronchoalveolar lavage fluid (BALF) from patients diagnosed with COVID-19, and included 213 Covid-19-infected patients admitted to the Third People’s Hospital of Shenzhen from January 11th to February 3rd, 2020, who were diagnosed by Guangdong CDC. A total of 866 respiratory tract samples, including 490 nasal swabs, 205 throat swabs, 142 sputum samples and 29 BALF samples, were collected at the time of admission and after each time point. According to the collection date, the samples were divided into 0~7 days, 8~14 days and ≥15 days after onset. According to the guidelines on prevention and treatment of Covid-19 infection issued by National Health Commission, patients were divided into severe and mild cases.

Three groups were divided according to the sample collection time after onset, and the viral nucleic acid was quantitatively determined.The positive rate of viral nucleic acid in sputum samples was the highest in the group of 0~7 days after onset.The positive rates of severe and mild cases were 88.9% and 82.2% respectively.Followed by a nasal swab.(73.3% and 72.1% respectively),The throat swab again.(60.0% and 61.3% respectively). In mild cases, the positive rate of nasal swab and sputum samples is similar.

The positive rate of BLAF samples collected from 8 to 14 days after the onset of severe cases was 100%.However, the BALF samples of 3 mild cases were negative. In all cases, the positive rate of sputum samples was the highest in the 8~14 days after onset, which was much higher than that of nasal swab and throat swab. It is worth noting that the positive rate of throat swab in severe patients is only 50%, and that in mild patients is only 29.6%.

In the group ≥15 days after onset,The positive rates of BALF, sputum and nasal swab from severe cases were similar. In mild cases, the positive rate of sputum and nasal swab is similar, which is much higher than that of throat swab.

For the diagnosis of viral nucleic acid in COVID-19’s patients,Sputum samples are the most accurate, followed by nasal swabs. It is not recommended to collect throat swabs for diagnosis.

The difference between oropharyngeal swab and nasopharyngeal swab

anusswab

Brother Hong:

1. Oropharyngeal swab is the least painful and most acceptable, but it has to bear the consequences of high false negative results. My suggestion is to use it according to the epidemic risk in the first epidemic area.

2. The positive rate of nasopharyngeal swab is higher than that of oropharyngeal swab, which is why nasopharyngeal swab is introduced into laboratory examination in the fifth edition of Diagnosis and Treatment Plan for Pneumonia Infected by Covid-19 (the fourth edition is still pharyngeal swab). If we want to pursue accuracy, it is suggested to use it, or to use it when screening people in close contact or sub-close contact. At present, the examination of returnees in domestic reports seems to be nasopharyngeal swab method.

3. Alveolar lavage fluid can’t be used for screening in the general population, so it is suggested that hospitals with ICU should use it for screening severe pneumonia patients living in ICU for COVID-19 patients.

4. Deep expectoration seems to be the best sample, but many patients in COVID-19 have a dry cough, which may not be possible.

5、anusSwabs were used in Daxing epidemic in Beijing, which is the first time to use this method in the screening process. In some literatures,anusAlthough the positive rate of swabs is not high, as I remember, it seems to be more than 10%, but it does not seem to coincide with the patients with oropharyngeal swabs, suggesting that the virus may attack the gastrointestinal tract, and also suggesting that there may be the possibility of gastrointestinal transmission in Covid-19. Although the initial symptoms of some patients are gastrointestinal symptoms such as abdominal pain and diarrhea, there are also ACE2 receptors in the digestive tract, which is theoretically possible, but it has not been confirmed at present. So,anusMy suggestion is that swabs can only be used as a supplement to nasopharyngeal swabs, and it is better to select patients whose first symptoms are digestive tract symptoms more accurately, which is unlikely to be used as a means of large-scale screening.

Solution:It is best for National Health Commission to issue a guiding document for large-scale screening, and make detailed regulations on what population and what sampling methods to adopt under what circumstances.,When local governments encounter an outbreak in COVID-19, it’s best to ask professionals to act as consultants and make choices according to the actual situation.

Third, the consistency of sampling ability of sampling personnel affects the sampling results.

Garbage in, garbage out (garbage samples produce garbage results), which is a sentence that inspectors often say.

The sampling team is huge, and the ability of sampling personnel must be uneven. In addition, people may have such fears about sampling, which often leads to unqualified samples.

Generally, there is an internal standard in the molecular diagnostic reagent to monitor the detection process, for example, RNaseP is used as the internal standard. If both the sample response curve and the internal standard response curve displayed by the fluorescence PCR platform do not jump, it means that the quality of the collected samples may have problems or false negatives may occur due to improper experimental operation, which needs to attract the attention of medical workers. The RNaseP internal standard can monitor the sample collection and ensure the accuracy of the test results.

Note: RNaseP is ribonuclease P, which is one of the most important ribozymes in human body. It is ubiquitous in all organs, tissues and cells of human body, and can detect RNA nucleic acid fragments from human body samples, and can also be used as an internal standard.

And I privately asked the relevant person in charge of our city’s temporary inspection center. He told me that every day in our hospital, some samples were told that they needed to be re-sampled because the internal standard did not jump. Imagine that you didn’t wipe down a few cells in your throat swab collection, so will the negative of this nucleic acid be accurate?

Solution:Consistency training for nucleic acid sampling personnel will greatly reduce the human influence, and it is easier to standardize the sampling process by taking such sampling methods as nasopharyngeal swab. Our city seems to have trained the nucleic acid emergency sampling team very early. What about your city?

In addition, if in the environment of large-scale nucleic acid sampling, when testing under the standard of 5-mixed 1 and 10-mixed 1, according to the above principle of internal standard, it seems that there is no single-tube ability in the quality control of internal standard. Therefore, especially those in the emergency sampling team, we must pay attention to the standard sampling methods and remember to collect qualified samples as much as possible.

Fourth, choose the right oneSampling device

The virus preservation tube mainly consists of a sampling swab and a virus nucleic acid preservation tube (containing virus nucleic acid preservation solution). There are many kinds of virus preservation tubes on the market at present.It is very important for epidemic prevention and disease diagnosis to choose the appropriate virus preservation tube, reduce the infection risk of medical inspectors as much as possible, and keep the virus RNA stable without degradation..

The preservation solution UTM used in traditional virus collection tubes is based on Hank’s solution, with gentamicin, fungal antibiotics, BSA (V), cryoprotectant, biological buffer and amino acids added. Its main purpose is to maintain the virus activity within a certain temperature range, so that it is convenient for health and epidemic prevention departments to further isolate, culture and trace the virus and determine the pathogen. This kind of non-inactivated tube, which I call it, is good for further work, but the sameLive virus increases the infection risk of medical staff in the whole process of sample collection, transportation and testing!Personally, I think this kind of sampling tube for inactivated virus should be a better choice for disease control sampling.

And clinicalIn order to achieve the purpose of rapid detection, it is not necessary to cultivate the virus, but only to crack the virus, so as long as the integrity and stability of the virus nucleic acid can be guaranteed.nowCommonly known as inactivation tube.Many inactivation tubes in China are used.The inactivation component is guanidine salt, which is in this inactivation tube in our hospital.Guanidine salt can crack the virus, but it can’t protect the integrity of nucleic acid for a long time.The virus nucleic acid may have been degraded during the delivery of the sample to the laboratory, which will also cause a "false negative" in the detection. Many studies show that both temperature and time can affect the test results, so the COVID-19 Laboratory Testing Guide has clear requirements for samples to be tested within 24 hours after collection and transported at 4 degrees Celsius. If it is necessary to exceed 24 hours, it should be stored at -70 degrees Celsius.

And some manufacturers put forward another inactivation tube, a kind of.containNon-guanidine saltThe virus preservation tube containing protein denaturant can inactivate the virus and ensure the preservation of virus nucleic acid at room temperature.And the virus nucleic acid is stably stored for 7 days.Does not degrade.

Solution:

1, from sampling to testing, it is necessary to mark the time, so that quality control can be carried out on the preservation time, which is basically no problem in a better hospital.

2. For the front-line staff to do the corresponding training, they should know the advantages and disadvantages of various types of preservation tubes and adopt the best sampling tubes suitable for local conditions.

3. It is best for the country to recommend the selection of sampling tubes with the support of relevant experimental data.

5. Failure of reagents caused by virus mutation?

After the virus mutation in South Africa, Britain, Brazil and other places, there have been cases that turned positive after ten tests in various parts of the world, including China.The FDA recently warned that virus mutation has caused some reagents to fail, and listed several kits that may be affected by mutation. This means that virus mutation may have led to the failure of some nucleic acid detection or persistent false negative.

The FDA listed several kits that may be affected by mutation:

Accula SARS-Cov-2 detection (Mesa Biotech): If the virus mutates at the 28881st base (GGG to AAC), the detection of this kit will be affected;

TaqPath COVID-19 Combo Kit (Thermo Fisher Scientific): This kit detects three genes at the same time, and the variant B.1.1.7 appearing in Britain will affect one of the detection results;

Linea COVID-19 detection (Applied DNA Sciences): This kit detects two genes at the same time, and the variant B.1.1.7 appearing in Britain will affect one of the detection results;

Helix, an American company doing nucleic acid detection, also noticed the influence of virus mutation on detection. The company’s nucleic acid detection simultaneously detected three Covid-19 genes: ORF1ab, N, and S. Because the B.1.1.7 strain that appeared in Britain had deletion mutation in S gene, ORF1ab and N could be detected in the detection, but S gene could not be detected (4). This phenomenon is called "S gene withdrawal".

In addition, the sensitivity of reagents from different manufacturers to COVID-19 is different, and the country also organized a national evaluation of reagents last year. butIn an evaluation study on the consistency and detection ability of seven domestic novel coronavirus nucleic acid detection kits published by Chinese Journal of Laboratory Medicine in July, 2020, it was proposed that "some kits have poor detection ability for weakly positive samples,It is suggested that weak positive samples should be rechecked by kits from at least two manufacturers to ensure the accuracy of the results."

Several targets of nucleic acid detection in Covid-19 are ORF1ab gene, N gene and S gene.

In the Technical Guide for Laboratory Detection of Pneumonia Infected in novel coronavirus issued by China CDC (hereinafter referred to as the Technical Guide), the two targets of nucleic acid detection in Covid-19 are ORF1ab gene and N gene respectively.

On January 6th, the Weekly Report of China Center for Disease Control and Prevention published the results of gene sequencing analysis of two cases of Covid-19 infection in Shijiazhuang and Xingtai. According to the published results, the strain prevalent in Gaocheng, Hebei Province, is different from the strain found in other places in China recently, and is homologous to the strain reported in Russia last July, belonging to strain B.1.1.123

Coincidentally, the mutation happened at the 28881 ~ 28883 bases of the virus gene of this strain, and this is exactly the position of the forward primer of the N gene!

This also explains why there were many negative results at that time.

I guess this is one of the reasons why the criteria for judging nucleic acid positivity have also changed.The judgment position that the single target is still positive after retest is positive.

Figure/Current Criteria for Judging Positive Cases in Technical Guide

Solution:

1. Require manufacturers of nucleic acid reagents to conduct confirmatory experiments on the current mutant strains and propose technical solutions.

2, all localities should introduce at least two kinds of better quality detection reagents, for control use.

3. Information about the failure of test reagents that may be caused by mutated viruses should be effectively and widely reported in domestic laboratories.

Six, the standard implementation in the process of laboratory testing

the pastAccording to the guidelines issued by relevant institutions, the collected samples need to be inactivated at 56℃ before nucleic acid detection, which is very likely to degrade the Covid-19 nucleic acid, which will lead to the failure of normal detection and ultimately improve the false negative rate.In the early daysInactivation treatment is carried out for the sake of biological safety, to protect the staff engaged in testing from virus infection.

But later, there were many voices of doubt in the academic circles, becauseViral RNA is easily degraded by ribonuclease, because this enzyme has the highest activity at 60℃. Ribonuclease comes from two aspects, one is the sample cells, and the other is the foreign pollutants in the process of collection, preservation and transportation.

Last February, there was a similar research article.The high-temperature inactivation process before virus nucleic acid extraction significantly reduces the amount of detectable virus nucleic acid templates, which has been pre-published on the platform of scientific papers of China Academy of Sciences.

And last May,The Journal of Clinical Chemistry published the research of Chinese scholars on Covid-19’s false negative test.The study confirmed that,Thermal inactivation can cause the increase of Ct value reflected by PCR and cause false negative results.Specifically, 46.7%(7/15) of the weakly positive samples were false negative after inactivation (a surprising proportion). Another inactivation method is to inactivate the virus by dissolving the virus protein with guanidine hydrochloride. This study confirmed that guanidine hydrochloride had little effect on PCR reaction, and the false negative rate was low, although there was also a false negative rate of 13.3%(2/15).

Related address: https://academic.oup.com/clinchem/article/66/6/794/5815979

I also inquired whether there was a 56-degree inactivation step in the detection process of CDC in the United States. Although my English ability was poor, I didn’t see this step by machine translation.

Including some other documents retrieved, it is also very clear that 56-degree inactivation does have a great influence on weakly positive specimens.

No matter the Manual of Nucleic Acid Detection in Medical Institutions in novel coronavirus (Trial) on July 13th, 2020 or the Manual of Nucleic Acid Detection in Medical Institutions in novel coronavirus (Trial 2nd Edition) on December 30th, 2020, there are corresponding descriptions.For the laboratory that has been inactivated with the sampling tube containing guanidine salt, there is no need to inactivate at 56 degrees for 30 minutes.This is only true if non-inactivated sampling tubes are used.


However, I learned from the familiar laboratory leaders that this is not the case. Many laboratories still require samples to be pretreated at 56 degrees for 30 minutes regardless of whether the tubes are inactivated or not. I can understand that they are worried about hospital infection and laboratory exposure. But generally speaking, reducing the false negative rate, increasing the detection amount and taking corresponding measures to control the epidemic situation as soon as possible, I think the corresponding suggestions in the corresponding guidelines are also the best choice from the overall situation and supported by data.

Our laboratory should not control the occurrence of hospital sensation and laboratory exposure at the expense of reducing the detection rate, but should focus on stricter control of experimental steps, more cautious PPE wear and higher laboratory environment.

Solution:

1. It is suggested that the state give special instructions to laboratories at all levels on this matter.

2. It is suggested that the country should further study the preservation solution of sampling tubes, and if there is any preservation solution that can not reduce the detection rate at 56 degrees for 30 minutes, it can also be recommended.

The above zero zero always said a lot of points, mainly about how to reduce false negative conclusions, hoping to give you a reference.

It’s been many days since I wrote this afternoon, mainly considering Spring Festival travel rush. Although the scale of Spring Festival travel rush is reported to have dropped by more than 75% this year compared with previous years, the population flow is still very strong. We may face the rising trend of an epidemic after Spring Festival travel rush, and how to make the work better may be a more urgent need before us.