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Medical science

The robot performs laparoscopic surgery on pigs without human help.

Enterostomy is one of the most challenging tasks in gastrointestinal surgery, which requires surgeons to sew the window accurately and steadily. Even the slightest hand shaking or misplaced needle can lead to leakage and may bring catastrophic complications to the patient. Recently, Johns Hopkins University has developed an intelligent tissue autonomous robot, STAR, which has successfully performed laparoscopic operations such as intestinal anastomosis in pigs without human guidance. The research is published in the journal Scientific Robotics.

STAR iterated from a 2016 model that can accurately repair pig intestines, but requires a large incision to enter the intestines and more manual guidance. The research team equips STAR with new features of autonomy and greater surgical accuracy, including specialized suture tools and advanced imaging systems that provide a more accurate field of view of the operation, as well as machine learning-based tracking algorithms that allow STAR to adjust its surgery plan in real time. STAR performed enterostomy on 4 animals, and the effect of enterostomy was significantly better than that of humans. The researchers say designing automated robotic systems to assist in surgery can make patients' treatment outcomes more consistent and predictable.

Medical science

Regenerate the broken leg of Xenopus laevis

The current medical technology is not enough to regenerate the limbs of millions of people who are disabled by disease or accident. However, a recent study in "scientific progress" offers hope: after being stimulated by drugs, Xenopus laevis with a broken leg has grown a new leg that is almost intact.

The researchers designed a special silicone cap (BioDome) that contains silk protein gels loaded with five drugs that can reduce inflammation, inhibit scar tissue formation, and stimulate nerve, vascular and muscle regeneration. After the amputated limb wound of Xenopus laevis was coated with BioDome for 24 hours, the comprehensive effect of the drug inhibited the tendency of the wound to form scar tissue and activated the molecular pathway related to embryonic development. Eighteen months later, the "new leg" of Xenopus laevis has a complete bone structure and richer neurons, with several "toes" at the end (without bone support). Regenerated limbs can respond to stimuli, and Xenopus can even use it to swim in the water. The researchers plan to next test the regeneration of BioDome in mammals.

Spaceflight

In 2010, after layers of rigorous selection, Wang Yaping became China's first batch of female astronauts. On June 11, 2013, Wang Yaping, together with Nie Haisheng and Zhang Xiaoguang, went into space aboard Shenzhou 10. On June 13 of that year, Shenzhou-10 was successfully stationed in Tiangong-1, and conducted China's first space lesson for primary and secondary school students across the country on June 20. Shenzhou-10 returned to Earth on June 26 and stayed in orbit for 14 days and 14 hours. On October 16 last year, Wang Yaping, Zhai Zhigang and Ye Guangfu boarded Shenzhou 13 in today's space, successfully stationed in the sky and core module, and will stay in orbit for six months. On November 7, Wang Yaping and Zhai Zhigang jointly completed the first extravehicular activity mission of the Shenzhou 13 crew, and Wang Yaping became the first female astronaut in China to carry out extravehicular activities; on December 9, Wang Yaping, together with Zhai Zhigang and Ye Guangfu, carried out the first space lecture on the Chinese space station. A few days ago, Wang Yaping became the longest astronaut in orbit in China. (Chinanews.com)

Nuclear fusion

Realizing the self-heating of Plasma matter in Nuclear Fusion

The experiment was carried out in the National Ignition Facility of the United States. 192 laser beams were used to ignite the plasma and quickly heated and imploded the target containing 200 micrograms of deuterium-tritium fuel, reaching a high enough temperature and pressure to trigger the self-heating fusion reaction. Previous attempts have been limited to the problem of controlling the shape of the plasma, so it is impossible to avoid disturbing the way in which the laser beam accumulates energy in the plasma, but this time the experimental design is improved so that the target can hold more fuel. and absorb more energy when it contains plasma. This experiment can produce up to 170 kilojoules of energy, and its efficiency is three times that of previous experiments.

Viral science

130000 new viruses were found in the genome database.

One virus alone may bring earth-shaking changes to human society, but virologists estimate that there are still trillions of viruses unknown. Recently, in a study published in the journal Nature, researchers found partial genomes of nearly 132,000 RNA viruses from existing genome databases.

The researchers focused on finding genes associated with RNA-dependent RNA polymerase (RNA-dependent RNA polymerase), which plays a key role in viral replication. To this end, the research team designed a set of cloud computing architecture, which can achieve ultra-high throughput sequence comparison. More than 130000 new viruses were found, including 9 coronaviruses, more than 300 viruses related to hepatitis D virus and more than 250 giant bacteriophages. For most viruses, researchers have not been able to obtain the complete genome, but they can still use known partial sequences to construct the pedigree relationship between viruses. Currently, the research team has created a public database that includes the tools they have developed and the screening results they have so far.

Zoology

The evolutionary path of echolocation in bats

The evolutionary pattern of the ganglion tube wall in Nell, bat. Picture from April Neander.

The phylogenetic characteristics of bats (combined with the analysis of evolutionary relationships with genomic data) indicate that their echolocation is either in the suborder Coleoptera (a suborder including large bats and small bats). Evolved independently in the order (mainly through visual navigation) and the positive suborder (small bat species with echo navigation), or evolved among bat ancestors, and later some species lost this trait. But this method of classification is controversial because in the past it was supported by molecular evidence and lack of anatomical support.