In 2023, a new dawn is burning on the horizon of science. From the electrodes in living organisms, to the "singing" of gravitational waves;From exploration at the level of monoatoms to Chinese's own laboratories in the vast expanse of space;From human beings' understanding of their own cellular level to artificial intelligence really entering our lives......The year 2024 is about to begin, and scientists who are moving forward are moving forward step by step towards a new era of science and technology.
On December 25, the top ten international science and technology news in 2023 were announced, sponsored by the Science and Technology Society, and jointly selected by some academicians and people of the Chinese Academy of Sciences and the Chinese Academy of Sciences.
The top 10 international science and technology news in 2023 are:
Electrodes "grow" in living tissue.
Male mice produce functional egg cells.
The double-slit experiment was reconstructed in the time dimension.
An international team unveils an epoch-making discovery of gravitational wave background radiation.
The single-atom X-ray signal is detected for the first time.
Human Y chromosome assembly and analysis completed.
Neural networks design new proteins.
China's National Space Laboratory was officially put into operation.
The most complete atlas of human brain cells to date has been published.
Large language models are constantly being iteratively upgraded.
1. Electrodes "grow" in living tissues.
The physical boundaries between living organisms and technology are blurring.
For the first time, Swedish researchers succeeded in cultivating electrodes in living tissues by injecting a gel with enzymes as "assembly molecules" and then using human molecules as triggers. The results, published in the journal Science in February this year, pave the way for the formation of fully integrated electronic circuits in living organisms.
Injectable gels for incubated electrodes in living tissues tested on microfabrication circuits. Thor Bakshid, Science
A team of researchers from Linköping University, Lund University and the University of Gothenburg in Sweden connected neural tissue with electronic devices. In general, a mismatch between rigid electronics and soft tissues can damage fragile living systems. But the team used an injectable gel to create a soft electrode directly in the body. When injected into living tissue, the enzymes in the gel break down endogenous metabolites in the body, triggering the enzymatic polymerization of the organic monomers in the gel, which converts them into stable, flexible conductive electrodes. The researchers verified this process by injecting the gel into zebrafish and medicinal leeches. The gel polymerizes in both organisms and "grows" electrodes within the tissue.
This method of creating electronic circuits directly within living tissues provides a way to develop diseases through nervous system electrical signals or modulation of neural circuits.
2. Male mice produce functional egg cells.
This is a study that can inspire or advance future fertility.
A report published in March in the journal Nature reported the results of stem cell research: the transformation of male mouse stem cells into female cells and the production of functional egg cells. About 1% of these eggs are fertilized to produce healthy offspring.
Egg cell data map. **Visual China.
Male and female gametes – sperm and oocytes (eggs), respectively, are produced from a class of stem cells called primary germ cells. These stem cells differentiate into gametes and require sex chromosomes to function properly.
Previous studies have explored the possibility of changing the sex of primary germ cells, and it has been found that the production of gametes or the reduction of only very fertile cells can be produced. But this time, Katsuhiko Hayashi's team at Kyushu University in Japan reported that it is possible to generate more robust egg cells using pluripotent stem cells. The team used ** cells from the tail of mature male mice (carrying XY chromosomes) and transformed these cells into induced pluripotent stem cells. They cultured these stem cells in vitro, a process that produced a subset of cells with rare Y chromosomes (about 6% of cultured cells), known as XO cells.
The continued development of these XO cells in the medium induces the replication of the X chromosome. Treating cells with the drug reversalin, which interferes with cells**, increases the replication efficiency of the X chromosome. The resulting double X chromosome cells are induced to differentiate into protogerm-like cells, which then differentiate into egg cells, which are fertilized and implanted into the uterus of a mouse to produce viable offspring.
Although the effect of converting male cells into female cells on genomic stability still needs to be more rigorously evaluated, this important result is important for future research and applications.
3. The double-slit experiment was reconstructed in the time dimension.
British scientist Thomas Young's observation of light wave interference in the 19th century is one of the most iconic experiments in the history of physics and has had a profound impact on quantum physics. Now, it's getting a new twist.
In April, British scientists recreated the famous double-slit experiment in time rather than space with the help of a "metamaterial" that can change properties in femtoseconds (trillions of a second). The latest experiments have revealed more of the fundamental properties of light and laid the groundwork for the creation of ultimate materials that can finely control light on spatial and temporal scales.
Original double-slit experimental art drawing. **British Journal of Nature**.
This experiment originally involved the diffraction of light through a pair of "slits" in space, but new research suggests that it is possible to achieve equivalent effects in time using double slits. The Imperial College London research team used a thin film of indium tin oxide in their experiments, and on ultrafast time scales such as femtoseconds, the material's reflectivity is altered by lasers to create a "slit" for light. The researchers achieved this by turning on and off the reflectivity of the semiconductor mirror twice in quick succession and recording the interference fringes along the spectrum of the light reflected from the mirror. Their experiments found that interference occurs between waves of different frequencies, rather than between different spatial locations.
This achievement may have a variety of applications in the future, such as optical switches for signal processing and communication or optical computing.
Fourth, the international team announced the epoch-making discovery of gravitational wave background radiation.
If the gravitational wave background is likened to an ancient and mysterious singing voice, then the "choir" performs at a different frequency every day. Now, through the monitoring of pulsars, scientists have finally heard the song, in other words, the first evidence of gravitational wave background.
After 15 years of data collection, in June of this year, scientists "heard" for the first time the eternal chorus of gravitational waves rippling through the universe, and the sound was much louder than expected. This is an epoch-making discovery of the gravitational wave background.
A pair of supermassive black holes (top left) emit gravitational waves that ripple through the fabric of space-time (artistic image). *North American Nanohertz Gravitational-Wave Observatory.
Gravitational wave background radiation is a superposition of many different gravitational wave sources, all of which vary in frequency and intensity, but all of which are low, and they should be present all around us and may tell us important information that it has been hidden for so long. Unfortunately, its existence and composition have been the product of only theories.
In a new series published in June in the Astrophysical Journal Letters, scientists report their results. The most likely gravitational wave background detected this time is a pair of supermassive black holes stuck in a "death spiral". These black holes are so large that they can reach billions of solar masses. Since almost all galaxies, including the center of the Milky Way, are entrenched in such a black hole monster. So when two galaxies merge, their supermassive black holes meet and start orbiting each other. Once the two black holes are close enough, they may be observed by pulsar timing arrays.
The team at the North American Nanohertz Gravitational-Wave Observatory says that at the moment they can only measure the overall gravitational-wave background, not the radiation of individual "singers" or "musical instruments." Even so, it was enough to surprise the entire astrophysical community, because "the sound in the background of gravitational waves is about twice as loud as expected". Mingarelli, an assistant professor at Yale University in the United States, said this is the upper limit of the models that can be created from supermassive black holes.
5. The single-atom X-ray signal was detected for the first time
To make a historic breakthrough in the way materials are inspected, it is not just about equipment upgrades, scientists need to innovate at the atomic level.
In June, scientists from Ohio University, Argonne National Laboratory, and the University of Illinois at Chicago captured the first single-atom X-ray signal, a breakthrough achievement that promises to revolutionize the way materials are examined.
Schematic diagram of the experiment where a single atomic X-ray was detected for the first time. **Network of Physicists' Organizations.
Because the X-ray signal produced by a single atom is so weak that conventional detectors are not sensitive enough to detect it. To solve this problem, the team added a sharp metal tip to a traditional X-ray detector that was placed just 1 nanometer above the sample to be studied. As the sharp tip moves across the surface of the sample, electrons pass through the space between the tip and the sample to generate an electric current, which essentially detects the unique "fingerprint" of each element, allowing the researchers to combine the ultra-high spatial resolution of scanning tunneling microscopy with the chemical sensitivity provided by intense X-ray illumination.
6. Human Y chromosome assembly and analysis completed.
This is the first truly complete human Y chromosome sequence and the last human chromosome to be fully sequenced.
Two articles published in August in the journal Nature published the assembly and analysis of the human Y chromosome. The study, involving more than 100 scientists from around the world, fills many gaps in the current Y-chromosome reference and provides insights into the evolution and variation of different populations.
The Y chromosome was the last of the 24 chromosomes in humans to complete sequencing. **National Human Genome Research Institute (NHGRI).
The human Y chromosome has been difficult to sequence and assemble due to its complex structure. More than half of the Y chromosome is missing from the current human reference genome assembly, resulting in a very incomplete understanding of the Y chromosome, limiting the understanding of its composition, complexity, and differences among different populations. As part of the Telomere-to-Telomere Alliance, scientists from the National Human Genome Institute, including Johns Hopkins University and the University of California, Santa Cruz, and other institutions, reported on the 62460029 base pair sequence of the complete human Y chromosome. This assembly corrects several errors regarding the Y chromosome in the current human reference genome assembly, while also adding more than 30 million base pairs to the reference genome, revealing the complete structure of multiple gene families, and identifying 41 new protein-coding genes.
In another article, the joint team assembled the human Y chromosomes of 43 males representing 21 different populations around the world. These assembly results elucidate the role of the Y chromosome in 18Genetic differences in 30,000 years of human evolutionary history. The researchers are integrating the new insights into primate research to dig deeper into the evolution of the Y chromosome and analyze clinically relevant genes that may affect cancer and many other diseases to help personalize medicine.
7. Neural networks have designed new proteins.
Proteins have always been difficult to model, especially when people want to "do it the other way around"—translating the desired function into a protein structure—which is a difficult challenge.
Visualization example of designing protein biomaterials. Markus Buehler, Journal of Applied Physics
The Massachusetts Institute of Technology team announced in August that it would combine attention neural networks with graph neural networks to better understand and design proteins. This method combines the two advantages of geometric deep learning and language models to not only improve the properties of existing proteins, but also to imagine new proteins that have not yet been designed in nature. The new model recombines the building blocks of nature by modeling the fundamentals and taking everything that nature has invented as the foundation. When the team trained the model, they used different proteins to determine their sequence, solubility, and amino acid components based on their function. Then, after receiving the initial parameters for the function of the new protein, the model unleashed its creativity and generated entirely new structures.
Coincidentally, Deep Thinking also unveiled a new generation of "alpha folding" this year, which not only has significantly improved accuracy, but also extends its range from proteins to other biomolecules, including ligands. The model is capable of achieving almost all molecules in the Protein Database (PDB) with atomic precision.
8. The National Space Laboratory of China was officially put into operation.
This year marks the 20th anniversary of the success of China's first manned mission. On August 18, the China Manned Space Engineering Office received good news: China's National Space Laboratory was officially put into operation, and space applications are being carried out in an orderly manner with frequent results.
The Wentian experimental module of the Chinese space station assembly display module photographed at the 14th Airshow China. Photo by Xinhua News Agency reporter Liu Dawei.
Lin Xiqiang, spokesman for China's manned space program and deputy director of the China Manned Space Engineering Office, said that the current space station scientific experiment facilities have basically completed in-orbit tests, operate in orbit stably and reliably, and have the ability to carry out space scientific research on a large scale. Up to now, the space station has carried out more than 60 experimental projects, tens of thousands of in-orbit experiments, obtained nearly 60TB of original experimental data, and sent down more than 300 scientific experiment samples.
As the largest and long-term manned space experiment platform in China's space history, the National Space Laboratory will take advantage of the environmental advantages in space to carry out scientific research, most of which cannot be simulated on Earth. The multiple experimental cabinets deployed in the Wentian experimental module, Mengtian experimental module, and Tianhe core module will carry out thousands of scientific experiments, explore the mysteries of the universe, and transform the incubated scientific and technological achievements into practical applications to benefit the lives of ordinary people on the earth.
9. The most complete atlas of human brain cells has been released so far.
With the development of biomedicine, what can we rely on to gain a new understanding of the identity of human beings as a species?One of the answers is brain science.
Science magazine.
In October, 21 articles** were published in the American journals Science, Science Advances, and Science Translational Medicine, publishing and explaining the most complete atlas of human brain cells to date. The series of studies involving scientists from many countries, revealing the characteristics of more than 3,000 brain cell types, will help to better understand the uniqueness of the human brain and advance research on brain diseases and cognitive abilities. Anthony Hannan, an expert at the Florey Institute for Neuroscience and Mental Health in Australia, was quoted by Nature as saying that this series of studies has for the first time mapped the human brain at the single-cell level, showing its complex molecular interactions, laying the foundation for a better understanding of the human brain.
Among them, the team of Kimberly Siletti, a neuroscientist at Utrecht University Medical Center in the Netherlands, performed RNA (ribonucleic acid) sequencing on more than 3 million cells covering 106 locations in the human brain, and analyzed and recorded 461 brain cell categories, including more than 3,000 subtypes. Studies have shown that neurons, as cells that send and receive signals from the brain and nervous system, vary greatly in different parts of the brain, especially in the brainstem region that connects the brain to the spinal cord, which contains a particularly multi-neuronal type, revealing different functions and developmental histories. This is an unprecedented granular analysis of the organizational structure of the human brain, including the adult brain and the developing human brain in the embryonic stage, at the single-cell level, identifying and delineating the astonishing diversity of human brain cell types, providing clues to the understanding of human psychiatric and neurological disease mechanisms.
10. Large language models are constantly iteratively upgraded.
2023 is the "Year of Generative AI".
Gemini can handle text, audio, and **. Google Inc.
This year, GPT-4's performance was considered "comparable to humans." About 4 months after the release of the chatbot ChatGPT, OpenAI, the company behind ChatGPT, announced the official release of GPT-4, a more powerful next-generation technology powered by ChatGPT, which has image recognition capabilities, advanced reasoning skills, and the ability to process 25,000 words, and performs as well as humans in some tests.
And on December 6, Google announced the launch of a new artificial intelligence model called Gemini, which it claimed outperformed GPT-4 models and "expert" humans in a series of intelligence tests. Google claims that Gemini's mid-range Pro version beats some other models, such as OpenAI's GPT35, but the more powerful Ultra surpasses the capabilities of all existing AI models. It has a score of 90% on the industry-standard MMLU benchmark, while an "expert" human is expected to reach 898%。This is the first time that an AI has beaten a human in a test and is the highest scoring of any existing model.
The test involves a range of tricky questions, including logical fallacies, ethical issues in everyday scenarios, medical issues, economics, and geography. In the same test, GPT-4 scored 87%, LLAMA-2 scored 68%, and Claude 2 scored 785%。Gemini beats all of these models in 8 of the other 9 common benchmarks.
*: Technology** 2023-12-26 Edition 03).
Editor: Nilo.