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Release: China Academy of Sciences
Scientific Development Report 20 13 is the 16th annual series of reports published by China Academy of Sciences, which aims to summarize the progress and development trend of world science and technology in 20 12, comment on scientific frontiers and major scientific issues, report the breakthrough achievements made by scientists in China, introduce the role of science in implementing the two strategies of "rejuvenating the country through science and education" and "sustainable development" in China, and make suggestions to the public.
Technology leads to division—
Debate on genetically modified food
Since 1983, the world's first transgenic tobacco plant containing antibiotics was successfully cultivated, genetically modified foods have been continuously developed and enriched. Genetically modified food is the product of the development of modern biotechnology, but it has not won unanimous praise as other new technologies in the past. Genetically modified food is entangled in a series of scientific debates and social ethics torture, which has become a hot social topic. Although people's reaction is not as fierce as before, every new information and new trend about genetic modification will still touch people's sensitive nerves and cause concern and debate.
The controversy surrounding the safety of genetically modified organisms has gradually become the focus of world attention. In these disputes caused by the development and new breakthrough of transgenic technology, the transgenic world gradually presents a divided picture:
1. Although genetically modified crops have been planted all over the world, there are still differences in attitudes towards genetic modification among countries.
2. Differentiation of social groups. This differentiation is fully manifested in the controversial events surrounding the safety of genetically modified organisms. The constant demands of different groups for the value and benefits of genetically modified organisms have intensified the differences in attitudes and positions among social groups.
3. Division within the group. On the issues related to genetic modification, differences within the group are also obvious. Whether it is the controversial event of transgenic, the selection or decision-making process of transgenic, or even the selection or decision-making of a specific transgenic product, not only different social groups, but also within the same group, their attitudes and positions are quite different.
So far, "Is genetically modified food safe?" This is still a very sensitive issue, which may set off a storm anywhere in the world today. When we observe people's attitudes and opinions in specific controversial events, although we will encounter various complicated answers, we can still distinguish two completely different attitudes and positions-positive or negative attitudes towards the safety of genetically modified foods.
Since the birth of genetically modified food, some people have paid more attention to its harmfulness. Although there have been many controversial incidents that questioned its safety, they were ultimately rejected because of insufficient evidence or non-compliance with experimental standards. Practice has proved that so far, genetically modified food has not caused real harm to human health, but at the same time, there is no exact experimental result to provide positive safety guarantee. It shows that there is indeed a risk problem.
Therefore, the safety of genetically modified food has double meanings of "harmfulness" and "risk". When we talk about the safety of genetically modified food, we should not only pay attention to those harmful problems, but also pay attention to those risks. The understanding of risk and its cognition will directly affect risk management and its institutional arrangement.
The revelation of science—
250 million years ago, deadly high temperatures led to species extinction.
Since the industrial revolution, carbon dioxide has been continuously emitted, and the trend of global warming has not slowed down at all. It is of great significance to study the greenhouse climate in geological history and its influence on living things for the future study of global warming.
About 250 million years ago, at the turn of Permian-Triassic, the biggest extinction event occurred on the earth in geological history. 95% of marine species and about 75% of terrestrial species, including corals and trilobites, have become extinct. There are different views on the nature and causes of this extinction. But whatever the reason, most of them have a direct or indirect causal relationship with the temperature change, so it is particularly important to quantitatively study the ancient temperature change in this period.
Equatorial sea level temperature is an important parameter to measure the environmental temperature in geological history. About 250 million years ago, South China was a multi-island ocean near the ancient equator at the turn of Permian-Triassic. It has the best marine stratigraphic record in the world. Scientists conducted isotope tests on 654.38 0.50 million conodonts, and obtained 654.38 0.62 sets of paleotemperature data. They found that in the early Triassic, the transition from the igloo climate to the temperature climate at the turn of the Middle Paleozoic lasted nearly 5 million years.
The science of fate—
Cell "regeneration"
20 12 Nobel Prize in Physiology/Medicine was announced. British scientist john gordon and Japanese scientist shinya yamanaka won prizes for discovering that "mature cells can be reprogrammed into pluripotent states". This discovery subverts the traditional concept of irreversible development.
A complete human individual is composed of many different types of mature cells, which are developed from fertilized eggs. The fertilized eggs differentiate into embryos, and the stem cells in the early embryos have the ability to differentiate into mature individuals, which is also called pluripotent cells. Traditionally, the process of development and differentiation from pluripotent state to mature specialized cells is irreversible.
1962, British scientist Gordon conducted a groundbreaking experiment. He transplanted the intestinal epithelial nucleus of tadpoles into enucleated egg cells and finally got normal tadpoles. It is proved that the nucleus of differentiated cells contains all the genetic material that constitutes an individual, and after reprogramming, it still has the ability to differentiate into various terminal differentiated cells of an individual.
1997, Dolly's birth announced that this concept also applies to mammals. This study provides a solid theoretical basis for the realization of induced pluripotent stem cells.
Scientists hope that the new technology of IPSC can eventually obtain a better disease model for drug research and development and disease treatment.
Technology poses a threat—
Network privacy protection is imminent.
With the deepening of social informatization, information technology represented by computers and computer networks has penetrated into every aspect of our lives. However, while the network brings great convenience to people's work and life, it also brings serious problems of information security and personal privacy protection.
At present, the current situation of Internet privacy protection in China is not optimistic. The main questions are:
Website security problems further lead to the security problems of website user information and data.
The threat of "phishing" faced by online banks is becoming more and more serious.
Information leakage caused by application software vulnerabilities and malicious programs in smart terminals such as mobile phones and tablet computers often occurs frequently.
The proliferation of Trojan virus has become the biggest threat to privacy protection.
Weak security awareness leads to leaks.
Lack of legal supervision.
20 12 top ten scientific and technological progress in the world 1. Curiosity landed on Mars successfully.
Curiosity is called the most advanced mobile science laboratory for human landing on other planets.
2. Canadian scientists developed artificial brains.
The functional brain model here is the closest to the real brain so far. This simulated brain running on a supercomputer has a digital eye that can be used for visual input, and its mechanical arm can draw its response to visual input. This simulated brain is so advanced that it can even pass the basic IQ test.
Scientists have designed the thinnest nanowires in the world.
A research team composed of Australian and American scientists has designed a nano-conductor, the thickness of which is only one tenth of that of human hair, but the conductivity is equivalent to that of the traditional copper conductor. This technology is expected to be applied in the field of quantum computer development. This new technology shows that computer components can be reduced to atomic level, which is a huge breakthrough.
4. Cancer stem cell research has obtained new evidence.
Researchers believe that figuring out which cancers may originate from cancer stem cells is the key to more effective treatment in the future.
5. Scientists discover "suspected" God particles
Higgs boson is a kind of boson with zero spin predicted by the "standard model" of elementary particles, and it is also the last elementary particle that has not been proved to exist. Because it is difficult to find and extremely important, it is also called "God particle". Scientists believe that this is an unparalleled achievement and will open up new fields of experiment and theoretical physics.
Japanese scientists gave birth to mice with "artificial" eggs for the first time.
A research team from Kyoto University in Japan accomplished this feat with eggs in the same way after giving birth to normal young mice with sperm from stem cells. This study is expected to eventually lead to new ways to help infertile couples get pregnant.
7. British research found a high-speed magnetic storage principle.
This is a revolutionary discovery. On this basis, we can develop a memory hundreds of times faster than the existing hard disk storage speed, and the information stored per second can reach trillions of bytes.
8. Astronomers have discovered a black hole whose mass is 65.438+0.7 billion times that of the sun.
This discovery may rewrite the theory of the formation and evolution of black holes and galaxies.
9. Adult stem cells were cultured from skin cells for the first time in Germany.
The Max Planck Institute in Germany announced on March 22nd that its researchers have successfully cultivated adult stem cells from differentiated somatic cells-skin cells, which is the first time in the world. Hans Scheler, an expert in stem cell research, explained that through the cultivation of adult stem cells, the regeneration of specific tissues can be more targeted and safer. This method has a good medical application prospect.
10. The first "super electronic" circuit came out.
American scientists used photons instead of electrons to create the first "super-electronic" circuit composed of photonic circuit elements.