The Nobel Prize in Physiology or Medicine was awarded to yoshinori ohsumi, a Japanese scientist, in recognition of his achievements in the study of autophagy mechanism. The Nobel Prize in Physics was awarded to David Solis, Duncan Haldane and michael kosterlitz for their theoretical discoveries in the topological phase transition and topological phase of matter. The Nobel Prize in Chemistry was awarded to Jean-Pierre Sauvage, Fraser stoddart and Bernard Feringa for their contributions to the design and synthesis of molecular machines.
Why are the grand prizes awarded to these scientists? What is the significance of their research results? What is the status and level of China's research in these fields?
Cells "eat themselves" to save themselves.
Although it is relatively backward in the field of life science, scientists in China are in a leading position in the specific direction of autophagy.
"Autophagy" literally means "eating oneself", but in fact it is a basic process of degradation and circulation of cells' own components. Generally speaking, cells can provide nutrition and energy by degrading its non-essential components, and can also degrade some toxic components to prevent cell damage and apoptosis. Dr Chengyu Liang, an expert in molecular microbiology and immunology at the University of Southern California School of Medicine, compared it to a kind of "self-rescue" of cells.
Chengyu Liang said that in a broad sense, autophagy mechanism is more like a part of a huge intracellular transport mechanism. Autophagy mechanism is like a transport line of cell self-purification and automatic environmental protection. It puts the metabolic wastes in cells and some expired useless or damaged cell parts into its unique means of transport-autophagy, and then sends them to the "garbage treatment plant"-lysosomes along a specific route for recycling and waste reuse.
The autophagy mechanism can also open the emergency transport channel to supply energy when the cell energy is insufficient. Therefore, autophagy mechanism is a very important part of the huge intracellular transport network system. "It is indispensable for maintaining the basic survival needs and balance of cells," Chengyu Liang said.
The concept of autophagy was put forward in the 1960s. At that time, researchers discovered the phenomenon that cells degrade their own components, but the related mechanism has never been known.
In the early 1990s, yoshinori ohsumi, a Japanese scientist, discovered the genes that played a decisive role in autophagy through a series of experiments on common yeast. Based on this research, he then clarified the principle of autophagy mechanism and proved that human cells also have the same autophagy mechanism.
In the press release issued on the same day, the selection committee pointed out that yoshinori ohsumi's research results will help human beings to better understand how cells can realize their own recycling. In many physiological processes, such as adapting to hunger or coping with infection, autophagy mechanism is of great significance, and yoshinori ohsumi's discovery opens the way for understanding these meanings. In addition, the mutation of autophagy gene will cause diseases, so interfering autophagy can be used to treat cancer and nervous system diseases.
As an expert on autophagy mechanism and regulation mechanism of multicellular organisms in China, Zhang Hong, a researcher at Institute of Biophysics, Chinese Academy of Sciences, had in-depth academic exchanges with yoshinori ohsumi. In Zhang Hong's view, although China is still in a relatively backward position in the field of life sciences, China scientists are in a leading position in the specific direction of autophagy. "Autophagy is a research hotspot in the field of life science in the world, and there are many teams involved in it in China. Professor Chen Biao from the Institute of Zoology of Chinese Academy of Sciences, Professor Chen from Tsinghua University and Professor Zhu Weiguo from peking university health science center have many original achievements. " Zhang Hong said.
Li Yu, a professor from Tsinghua University, returned to China to teach in 2008 and was deeply touched by the progress made by China in the field of life sciences in recent years. "If autophagy research is compared to a building, then scientists in China have added a new layer to this building."
"The study of autophagy has just begun," Zhang Hong said. Scientists in China are capable of making greater contributions in this field.
Introducing the concept of topology into physics research
On the basis of theoretical prediction, China scientists showed the behavior of fermions in TaAs to the world for the first time.
The selection committee said that David Solis, Duncan Haldane and michael kosterlitz's application of topological concepts to physics research was the key to their achievements.
For many people, "topological phase transition and topological phase" is a daunting and profound theory.
Topology itself is a mathematical concept, which describes the property that geometry can remain unchanged under continuous elastic deformation (no tearing or truncation). "For example, no matter how you knead a piece of dough, the number of holes on its outer surface is 0. If it is torn and then glued, it can be made into bagels, and the outer surface of bagels has 1 holes. The number of this hole is the amount that the dough or bagel remains unchanged under continuous elastic deformation, and it is a topological invariant that distinguishes the two geometric shapes, that is, the topological number. " Weng Hongming, a researcher at the Institute of Physics, Chinese Academy of Sciences, said.
Different forms of matter are called different "stages" or states of matter. Phase change is the process of "changing face" of matter, that is, the process of changing from one phase to another. For example, the transformation of water between solid, liquid and gas with the change of temperature is actually a phase change process. The phase transition process is usually accompanied by the change of material properties and properties. The "topological nature" of matter has changed, which is called "topological phase transition". Topological phase transition is accompanied by the change of topological number.
However, if matter becomes extremely thin, does the phase of matter still exist? The selection committee said that the physical phenomena in the plane are completely different from the world around us. Even a very sparsely distributed substance contains millions of atoms, and the behavior of each atom can be explained by quantum physics, but many atoms will show completely different properties when combined. The research results of the three winners reveal the decisive influence of topological properties on the quantum state and quantum phase transition of matter.
Kosterlitz and Solis pay attention to "strange phenomena" in the plane world. Compared with the commonly described three-dimensional world, they found that the surface or interior of a very thin layer can be considered as two-dimensional, one of which is called "phase transition from superfluid to normal fluid", and the main decisive factor is completely different from people's previous understanding. Haldane found that the concept of topology can be used to explain the characteristics of small flux linkage in some materials. He found that different atomic magnetism made these chains show completely different properties. Haldane has also done a lot of pioneering work in quantum Hall effect.
As the Royal Swedish Academy of Science said, this year's award-winning research results have opened an unknown world. Thanks to the pioneering research of these three winners, scientists can now continue to explore new phase transitions of matter. Researchers believe that topological materials will be applied in the future research and development of electrons, superconductors and quantum computers.
In the field of topology research, scientists in China have also done a lot of commendable work, some of which are still at the forefront of international topology research.
Weng Hongming introduced that as early as 2009, Dai of the Institute of Physics of the Chinese Academy of Sciences cooperated with Chinese scientists to theoretically predict the Bi2Se3 topological insulator materials, which is the most widely studied at present. At the end of 20 14, the research groups of Institute of Physics, Dai and Weng Hongming of Chinese Academy of Sciences predicted theoretically that TaAs crystal is a nonmagnetic heterogeneous semimetal. Under their impetus, in 20 15, Chen Genfu's team of Institute of Physics of Chinese Academy of Sciences prepared high-quality samples, and Ding Hong and Maeda's team observed the fermion behavior in TaAs by using the "dream line" of Shanghai light source, which was the first time that this kind of special electrons was presented to the world. Waier semimetal is an important research direction of topological semimetal. This research achievement was rated as "one of the top ten breakthroughs in 20 15" by Physical World sponsored by British Physical Society and "eight highlights in 20 15" by american physical society Physics.