Disease control experts talk about flu prevention in the office: wash your hands frequently and don’t encourage you to go to work sick.

  Cctv newsOn January 25th, a press conference was held in National Health Commission to introduce the prevention and control of infectious diseases in winter and spring and the prevention and response of common diseases during festivals. Li Zhongjie, a researcher at the Center for Disease Control and Prevention of China, said in response to a reporter’s question that some non-drug interventions are very important for the flu in a confined space.

  journalistThe question is about influenza prevention. At present, most of the working environment is a writing room. In this state, one person may get sick, which may cause everyone to get sick. How to prevent influenza in this case?

  Li ZhongjieA place with a relatively closed writing room is indeed a high incidence place for the spread of respiratory diseases, especially in winter and spring, when it is cold and airtight outdoors, it is easier to spread pathogens. For the flu, some non-drug interventions are very important in a confined space, that is, some good hygiene habits, especially in the writing room mentioned just now, such a specific place. If an individual has flu-like symptoms,Patients are not encouraged to go to work sick.For the sake of your own health and the health of others around you, you mustDo isolation.. If the illness gets worse, you should seek medical treatment in time, which is a good protection for yourself and others.

  Emphasize again aboutWash your hands frequently.This habit is simple and easy to do, but if you really develop good habits and stick to them, you can prevent many other diseases, including influenza, including other contact-borne diseases.

  In such a specific gathering place,Environmental cleanliness and hygieneVery important, the spread of influenza is mainly through two ways. One way is close, the droplets spread between the patient and the surrounding people. When the patient coughs or sneezes, the droplets are directly sprayed into the mouth of the surrounding people. In addition, after the virus is discharged from the patient, it will stay on the surface of the object for a period of time. If people around it touch the mouth and nose again, it is also a way to spread the flu. Therefore, it emphasizes the daily cleanliness of personal working environment and public environment, and insists on daily cleaning.

  Attachment: Personal daily protection knowledge of influenza provided by Health and Health Commission.

  To prevent respiratory infectious diseases such as influenza, we should first start with personal daily protection, and pay attention to good personal hygiene habits at ordinary times, including:

  (1) Wash your hands frequently;

  (2) Regularly open windows for ventilation;

  (three) take the initiative to vaccinate against influenza before the arrival of the influenza epidemic season;

  (4) During the influenza epidemic season, the elderly and patients with chronic diseases should try their best to avoid going to crowded places and contact with patients with respiratory infections;

  (5) After flu-like symptoms appear, keep good respiratory hygiene habits, cover your mouth and nose with paper towels and towels when coughing or sneezing, wash your hands after coughing or sneezing, and try to avoid touching your eyes, nose or mouth.

  (6) When family members have flu patients, they should try to avoid contact with each other, especially when there are elderly people and patients with chronic diseases at home.

  (7) When the parents of children with flu symptoms go to the hospital for treatment, they should also do a good job in protecting the children and themselves (such as wearing masks) to avoid cross-infection.

The stock market closed on the 6 th: the Shanghai Composite Index fell 5.58%, and more than 1,000 shares in the two cities fell.

  Beijing, Beijing, May 6 (Xie Yiguan) On the 6 th, the three major stock indexes of A shares gapped lower and continued to fall in intraday trading. Individual stocks generally fell, and the industry sector was exhausted. The three major stock indexes all fell below the 60-day moving average, the Shanghai Composite Index fell below 3,000 points, and the risk was 2,900 points. More than 1,000 stocks in the two cities fell.

  At the close, the Shanghai Composite Index dropped 171.88 points, or 5.58%, to close at 2906.46 points. The Shenzhen Component Index fell more than 700 points, down 7.56%, and then lost 9000 points after falling below the 10,000-point mark, closing at 8943.52 points. The Growth Enterprise Market Index fell 7.94%, falling below the 1600 and 1500 mark and closing at 1494.89. The turnover of the two cities in the whole day was 657.912 billion yuan, which was significantly enlarged compared with previous trading days.

  Today, the A-share sector all fell green. Brokers in the industry sector almost fell, while telecom operations, IT equipment and software services were among the top losers, falling more than 8%. The banking sector with the smallest decline also fell more than 2%. In the concept sector, domestic software, 5G concepts and chip concepts fell by over 9%.

  On the disk, the stocks in the two cities are generally falling, with only 109 stocks closing up, 3,467 stocks falling and 1,147 stocks falling. Among the limit stocks, the GEM has become a concentrated place, with over 300 GEM stocks falling. It is worth noting that there are more than 100 5G concept stocks among the stocks that have fallen below the limit.

  Not only A shares, but also Hong Kong stocks were under pressure on the 6th. As of press time, the Hang Seng Index fell more than 3% to 29,062.57 points. The index of state-owned enterprises also fell more than 3% to 11161.9 points; The red chip index fell more than 2.9% to 4,483.47 points.

  On the 6th, the central parity of RMB against the US dollar was lowered by 58 basis points to 6.7344, the lowest since February 20th. In the morning, the offshore RMB fell sharply against the US dollar, falling below the 6.80 mark and once rushing to 6.8211.

  On the same day, the Central Bank of China announced that a lower deposit reserve ratio will be implemented for small and medium-sized banks from May 15, and about 1,000 county-level rural commercial banks can enjoy this preferential policy, releasing about 280 billion yuan of long-term funds.

  It is worth noting that on the 6th, A-shares went northward with a net outflow of 5.188 billion yuan, including 3.072 billion yuan from Shanghai Stock Connect and 2.116 billion yuan from Shenzhen Stock Connect. In the past April, the net outflow of northbound funds was 17.997 billion yuan, the second highest in a single month in history.

  However, MSCI’s first increase in the proportion of A shares from 5% to 10% will take effect at the end of May. CICC estimates that the proportion of passive funds may be around 20%, and about 20-30 billion yuan will enter the market around the end of May.

  According to a recent report of CICC, the short-term pressure of A-shares has been released after previous adjustment, and the overall valuation is not high. Therefore, the future outlook of A-shares should not be overly pessimistic, and structural opportunities may still be positive, focusing on the general trend of consumption upgrading and industrial upgrading.

  On April 30th, the National Bureau of Statistics and China Mining Association released data. In April, the purchasing managers’ index (PMI) of manufacturing industry was 50.1%, down 0.4 percentage points from the previous month, and remained in the expansion range. Guangfa Hang Seng believes that the structural contradiction of China’s economy still exists, and the economy is in transition to recovery, and the market will still repeatedly play games around theme stocks.

  Some securities analysts believe that compared with before and after the Spring Festival, the market’s expectation of economic and policy trends is more uncertain. However, many institutions believe that although the unilateral rise in the first stage has passed, the safer configuration window in the market outlook needs to wait further, and the market is expected to enter the second stage.

  Haitong Securities Strategy Team issued a document saying that this wave of adjustment since 3288 points of the Shanghai Composite Index belongs to the retreat after the first-stage valuation of the bull market has been repaired and increased. In the short term, the phased adjustment has not yet ended, and it is necessary to wait for the fundamental relay when the future rest ends and enters the second wave of the bull market.

  Founder Securities pointed out that the next four weeks will still be an important observation window. In the first week after the May Day holiday, if the Zhouyang line can be closed, it will help to resolve the risk of further decline, which deserves special attention. (End)

The competition is just around the corner, and the Shougang ski jumping platform starts to make snow! Why use "ice snow"?

Introduction: Actually, the snow used in the competition does not depend on nature, but relies on funa technology.artificial snowHow to "mass production"? What is "ice snow"?
The 2023/2024 season International Snow Federation Single Board and Freestyle Ski Platform World Cup, hosted by the International Snow Federation and co-hosted by China Ski Association, Beijing Municipal Sports Bureau and Beijing Shijingshan District People’s Government, will be held in "Snow Flying", the ski platform of Shougang from November 30th to December 2nd.
On November 17th, the snow-making work of Shougang ski jumping platform was officially started. The snow-making work will last until November 27th. After the snow-making work is completed, athletes will be trained before the competition.
(Source: Beijing Evening News)
Snow quality is an important guarantee for ski jumping events. Because this year’s competition time is earlier than in previous years and the weather temperature is higher, the problem of snow making has attracted everyone’s attention.
Such worries are actually unnecessary. The development of snow-making technology is enough for China to realize "freedom of using snow".
Artificial snow is safer and more controllable.
Considering the uncertainty of natural weather process, especially snowfall, international events of snow sports generally use artificial snow to lay snow tracks. The reason is that, on the one hand, funa’s technology is artificially controllable, so it is not necessary to "rely on the sky to eat"; On the other hand, the threshold of this technology is relatively low-as long as the temperature is lower than 0℃, the snow machine can work.
"Usually, funa uses a’ snow cannon’ type snow machine. The principle of this machine is divided into two types. One is to use an ice-making device to produce a small piece of ice, and then use the piece of ice as raw material to make snow; The other is the traditional high-pressure water mixed with air to make snow. " Su Zhengjun, a senior engineer at the Weather Modification Center of China Meteorological Bureau, said.
The traditional artificial snow is to inject water into a special nozzle or spray gun, which uses high-pressure air to divide the water flow into tiny particles. When these water droplets meet the cold outside air, they will quickly solidify into ice crystals and become the well-known snowflakes before landing.
"Artificial snow takes a short time to form and grows fast, and the shape of snowflakes is basically the same. Snowfall in natural weather will have obvious changes in hardness the next day. " Su Zhengjun explained.
In the early morning, when the outdoor temperature is low, the natural snow usually has a high degree of solidification. At this time, the snow is hard, similar to "ice slag". Although this state of snow will make skiers reach a faster sliding speed, it also makes the snowboard’s grip on the ground poor. Especially for beginners, if the soft natural snow is not compacted, the snowboard is very easy to fall into the snow, causing accidents such as rollover and emergency stop.
▲ The smooth machine-pressed snow trail is also called "noodle snow" by fans, and skiing on the machine-pressed snow trail is compared to "eating noodles". The picture shows the snowy road of Changbai Mountain International Resort in Jilin (Source: Xinhua News Agency)
Create a "rubber runway" on the snow
It is easy to understand that artificial snow can help us get rid of our dependence on natural snowfall. So why do some winter sports tracks still use funa in areas with abundant snow and snowfall all the year round?
This has to mention another advantage of funa: customization. According to the needs of different events and different venues, artificial snow can freely adjust the particle size, water content and hardness of snowflakes.
For example, alpine skiing, as a traditional event in the Winter Olympics, has always been known as the "jewel in the crown of the Winter Olympics" because of its strong ornamental value, but the participants in this project are very fast (the top speed can reach 248 kilometers per hour) and the danger is very great, so the requirements for the track are more stringent. In order to build a snow trail that meets the international standards of alpine skiing, the snow used is not ordinary natural snow, but artificial "ice-like snow".
The so-called icy snow is used to describe a state of snow quality on ski resorts. In this state, the density of snowflakes is about 0.65 g/cm3, and the surface of the snow trail remains crystalline, just like a thin "ice shell", which is similar to the ice surface. This kind of snow trail has high hardness and is not easy to be destroyed. It can ensure that the surface of the snow trail is not deformed when the athletes turn at high speed. No matter which time the athletes play, the state of the snow trail is the same and relatively perfect.
▲ Competition-level snow trails are more dense and "more porcelain", sliding faster, but falling more painful (Source: "Chai Know" WeChat WeChat official account)
If icy snow is used to pave the pavement for alpine skiing, it is like building a "plastic track" in the snow, which can not only reduce the friction between the track surface and snowboards and significantly improve the athletes’ performance, but also improve the athletes’ comfort when skiing, protect their body joints and prolong their professional sports career as much as possible.
Shougang ski platform, using crushed ice to make snow.
The snow-making of Shougang ski jumping platform adopted the method of breaking ice to make snow. One side of the ice is crushed into snow powder by an ice crusher, and the snow powder is leveled and compacted by a snowmobile, and piled up from the bottom of the big platform from bottom to top, and the snowy road is paved. After the track is paved, the Xiang Xue surface will be sprayed with water and salt to form the final "ice-like snow" to ensure that the snow conditions of each athlete are basically the same when they slide.
Snow quality is an important guarantee for ski jumping events. "Ice snow" can not only improve athletes’ performance and ski comfort, but also protect athletes’ health. The team has many years’ experience and has served large-scale events such as the Winter Olympics. The team will also communicate with athletes on the quality of snow to satisfy their feelings.
Different from other temporary venues, Shougang ski platform, as the world’s first permanently reserved and used platform competition venue, can meet the load-bearing requirements of snowmobiles in track construction, which also creates a precedent for snowmobiles to lay snow trails on the platform.
(Source: Beijing Evening News)
Snow preservation and snow storage technology to ensure track quality
In fact, for a long time, building a high-quality ice-like snow track has been a technical difficulty in China’s ice and snow industry. In order to welcome the Beijing Winter Olympics and Paralympic Winter Games, researchers have made unremitting efforts to establish the territorial parameters for making ice-like snow in Yanqing and Zhangjiakou in Beijing. At the same time, with the help of complete snow-making techniques of water injection and compaction, qualified ice-like snow that meets the climatic conditions of continental monsoon region has been successfully made. Natural snowfall in winter in the local mountainous areas has become the "landscape snow" to decorate the Winter Olympic Games area.
In fact, for the high-standard Winter Olympics Road, natural snowfall is a "burden". If there is snowy weather, the soft natural snow will lead to the "mirror-smooth" icy snow track falling short. In addition, because Beijing Winter Olympics and Paralympic Winter Games are in the alternating period of winter and spring, they may encounter other extreme weather, such as sudden rain, which will cause thin ice on the track surface and increase the risks faced by athletes in the competition.
▲ On February 23, 2021, the staff of the National Alpine Ski Center in Yanqing Division ("Xuefeiyan") were inspecting and trimming the track (Source: Xinhua News Agency)
After the planning of scientific research personnel, if it is really "bad weather", the staff will immediately use the snow-pressing machine to re-compact the snow trail and carry out emergency finishing on the track. At the same time, in order to ensure the quality of the track, they will also use automatic measuring instruments such as ice and snow hardness tester and ice and snow particle size meter for quick detection, so as to effectively ensure the quality of snow and resume the normal race in the shortest time.
It is reported that in order to ensure sufficient snow during the competition, the 2022 Beijing Winter Olympics also made a bold attempt in snow storage: when the temperature is low in winter, make qualified snow in advance, and then store it in a flat site until the next year.
This seemingly impossible scheme has passed the feasibility test as early as 2017. The Beijing Winter Olympic Organizing Committee has successfully carried out the snow storage experiment in Yanqing Shi Jinglong Ski Resort. After the test of the following spring and summer, more than 60% of artificial snow was successfully stored.
Related reading:
How many steps does it take to build an icy snow track?
Building an international and high-level ice-like snow track for Olympic events is not only due to the snow machine. At present, the icy snow track can be divided into two categories: racing track and competitive track. Take the ice-covered snow racing track as an example;
First, the snowmobile needs to open the snow trail, break the snow blocks and loosen the snow surface;According to the location of the track and the temperature at that time, inject water into the snow-only in this way can we ensure that the track has a certain strength and enough elasticity;The embryonic form of an icy snow track is basically formed by constantly turning over the wet snow and pressing it evenly again and again.
▲ Different from the watering method of the racing track, the competitive track adopts the "Z-shaped water injector" water injection method (Source: Beijing Daily)
After that, the staff should ensure that the thickness of the ice-like snow layer is consistent, and there are no big holes in the snowy road. After confirming that everything is correct, flatten the track and let the snow layer form a shiny "ice shell" from bottom to top;After completing all the steps, the staff also need to clean up the floating snow on the track.At this point, a qualified "mirror-like" icy snow track can be put into use.
Author/Reporter Wang Xueying
Editor/Ding Lin New Media Editor/Fang Yongzhen
Interview experts:
Su Zhengjun (Senior Engineer, Weather Modification Center, China Meteorological Bureau)
Source: Beijing Science and Technology News, part of which is integrated with Beijing Evening News.
Reporting/feedback