Shenzhou-14 taikonauts meet press for first time since returning to Earth

Seventy-five days after having returned to the ground, the Shenzhou-14 crew members met the press on Friday and were in good spirits. They were also in good physical and mental shape, said health experts at the press conference, noting that they have now moved into the recovery observation stage and will be able to return to normal soon.

The recovery of normal body function for the taikonauts after they returned from space consists of three stages - quarantine, convalescence and observation - according to health experts speaking at the press conference on Friday.

The Shenzhou-14 crew has completed the first two stages, showing a stable emotional status and good mental condition, and their body weight has stabilized at pre-flight level. The muscle strength, endurance and cardiorespiratory reserves have been further restored, achieving the expected results.

They have now moved into the third stage of recovery observation. After an overall evaluation, the three taikonauts will be able to return to normal training and work.

After concluding their six-month stay at the China Space Station and completing the first direct handover in orbit in the country's history, Chen Dong, Liu Yang and Cai Xuzhe, the three taikonauts of the Shenzhou-14 safely returned to Earth on December 4, 2022.

It marked the first return mission after the completion of the China Space Station's T-shape basic structure.

Update: 21 people die and 6 are missing due to mountain flooding and mudslides caused by heavy rainfall in Xi’an, NW China’s Shaanxi Province

Twenty-one people have died and another six are missing as of Sunday evening after heavy rainfall hit Xi’an, Northwest China’s Shaanxi Province, and caused mountain floods and mudslides on Friday evening. 

Due to the impact of short-duration heavy rain, mountain floods and mudslides struck a village in Chang’an district in Xi’an around 6 pm on Friday. The disaster has damaged two houses occupying a total area of 300 square meters, destroyed three sections and slightly damaged 21 sections on the National Highway 210, damaged three electric power supply infrastructures and left 900 households out of power, according to Xi’an Bureau of Emergency Management. 

Xi’an city immediately set up an on-site command center, organized a total of 14 rescue teams including firefighting and police departments with more than 980 personnel, and deployed over 1,100 units of equipment and tools including life detectors, satellite phones, excavators, and search and rescue dogs, working around the clock to carry out search and rescue as well as disaster relief operations.

As of Sunday evening, 186 residents have been relocated and resettled, three severely damaged sections of the National Highway 210 have been restored, 21 slightly damaged road sections are under reinforcement, communication services have been restored in 49 affected areas, and power supply has been restored to 855 households.

The city is making every effort to seize the critical period for rescue operations, continuing to search for missing individuals restlessly, as well as remove risks to prevent the occurrence of secondary disasters.  

Preliminary investigations showed that two houses in the village were washed away, a with nearby roads, bridges, power supplies and other infrastructures damaged, leaving local residents partially cut off with the outside world. 

Local media reported that as of Sunday Morning, four people had been confirmed dead, while 14 others remain missing. 

The Xi'an detachment of the armed police force in Shaanxi deployed more than 100 personnel to the impacted area. Preliminary search and rescue operations remain underway. 

As of Sunday morning, rescue forces have transferred 81 residents and 11 vehicles to safe locations, and are assisting with the search and recovery of four deceased villagers, with emergency workers scanning an area 65 kilometers in length along a nearby river.  

According to a local villager surnamed Li (pseudonym), flooding and mudslides began following one or two hours of heavy rain on Friday afternoon. Two dwellings swept away by flood waters operated agritourism business, but there was yet to be confirmation whether guests were inside during flooding. 

Local fire department, police and emergency management authorities are working to coordinate rescue efforts. 

Upon receiving the report, China's Ministry of Emergency Management has dispatched a working group to the disaster site to assist with rescue and response efforts and have also mobilized a local fire and rescue team consisting of 207 personnel to carry out rescue operations.

Local govts support state-owned enterprises expanding hiring of graduates, expected to help alleviate unemployment pressure

Many localities have issued policies to encourage state-owned enterprises to play an exemplary role in stabilizing employment and expand recruitment of college graduates, with some provinces and cities requiring no less than half of the hiring quota at state-owned enterprises be dedicated to college graduates.

The office of the Guangdong Provincial People's Government recently published a notice on optimizing and adjusting stable employment policies and measures to promote development and benefit people's livelihood. Showing clear support for state-owned enterprises expanding the scale of recruitment, the notice pointed out that the number of new college graduates recruited by state-owned enterprises in the province this year should be no lower than that of 2022.

Additionally, East China's Anhui Province also issued a notice requiring state-owned enterprises to recruit at least 50 percent of fresh graduates to ensure that the number of college graduates accepted by state-owned enterprises remains stable.

Besides this, the provinces of Hunan, Gansu and Jiangxi have made similar notices. Among them, Central China's Hunan Province requires that provincial state-owned enterprises accept more than 4,700 graduates, while Northwest China's Gansu requires provincial state-owned enterprises to recruit more than 5,000 college graduates in 2023. Meanwhile, provincial state-owned enterprises funded and supervised by the Jiangxi government are set to recruit no less than 5,000 college graduates this year.

The number of college graduates is expected to reach 11.58 million before the end of 2023, an increase of 820,000, according to estimates by China's Ministry of Education. 

South China's Hainan Province proposed in July that state-owned enterprises should play a role in attracting young employees and ensure that no less than 1,000 college graduates are recruited by the end of 2023, while East China's Fujian Province is requiring the implementation of a one-time increase at state-owned enterprises to ensure that the number of college graduates recruited exceeds that of 2022.

An employee at PetroChina's Beijing branch surnamed Li told the Global Times on Sunday that more than 80 percent of new hires at the branch office in 2023 have been graduates. Moreover, a staff member surnamed Zhao with the Industrial and Commercial Bank of China's research and development center in Beijing told the Global Times that the recruitment rate of graduates at the company in 2023 reached 90 percent.

The demand for state-owned enterprises to expand the scale of recruitment is in response to graduate demand and aims to alleviate the current problem of comparatively low youth employment, Xiong Bingqi, director of the 21st Century Education Research Institute in Beijing, told the Global Times on Sunday. 

According to Xinhua News Agency, as of August 11, the number of college graduates recruited by central enterprises and state-owned enterprises under the national asset supervision system has exceeded the same period in 2022. With the summer recruitment of state-owned enterprises gradually underway, it is expected that the recruitment volume will continue to increase in the future.

The State-owned Assets Supervision and Administration Commission of the State Council has also made arrangements for the recruitment of college graduates by state-owned enterprises in 2024 at a meeting held in July.

The meeting required central enterprises and local state-owned enterprises to strive to complete the recruitment plan for the 2024 college graduates by the end of August, and gradually provide a batch of high-quality positions in September and October, in order to identify a group of high-quality target candidates as early as possible.

According to the Xinhua News Agency, as of August 11, the number of college graduates recruited by state-owned enterprises under the national asset supervision system has exceeded the same period in 2022. With the summer recruitment of state-owned enterprises gradually underway, it is expected that recruitment volume will continue to increase in the future.

The State-owned Assets Supervision and Administration Commission of the State Council has made arrangements for the recruitment of college graduates by state-owned enterprises in 2024 at a meeting held in July.

The meeting required central and local state-owned enterprises to strive to complete recruitment plans for the 2024 college graduates by the end of August, and gradually provide a batch of high-quality positions in September and October, in order to identify a group of high-quality target candidates as early as possible.

New tyrannosaur bridges gap from medium to monstrous

A fossil from a new species of dinosaur is helping to bridge a crucial 20-million-year gap in tyrannosaur evolution.

The key fossil is a 90-million-year-old, grapefruit-sized partial skull from Uzbekistan’s Bissekty Formation. This tyrannosaur braincase, the first well-preserved one found from the mid-Cretaceous period, shows that, although still small, tyrannosaurs of the time already had brain and ear features of later tyrannosaurs. Researchers have dubbed the in-betweener Timurlengia euotica, meaning “well-eared.” They describe the new species in a paper to appear in the Proceedings of the National Academy of Sciences.
The braincase sheds light on a long-standing mystery: how tyrannosaurs evolved in the gap from 100 million to 80 million years ago from an “average Joe” horse-sized predator in the Early Cretaceous to the huge apex predators they became in the Late Cretaceous. “Our study is the first to show that the sophisticated brain and hearing of big tyrannosaurs evolved in smaller-bodied species, long before tyrannosaurs got giant,” says study coauthor Stephen Brusatte, a paleontologist at the University of Edinburgh. These advantages, he adds, may have helped tyrannosaurs become such successful — and eventually enormous — predators.
Analyzed against a database of other tyrannosaur skulls, the braincase shows that Timurlengia’s brain and ear “are almost identical to T. rex, just smaller,” Brusatte says. In particular, the dinosaur’s long cochlea, a part of the inner ear, is a signature of bigger, badder Late Cretaceous tyrannosaurs. “The long cochlea would have meant better sensitivity to low-frequency sound,” Brusatte explains. That sensitivity would have enabled Timurlengia to detect very subtle or distant sounds, giving the dinosaur clear advantages over other predators.

“Timurlengia fills an important gap in both time and evolution,” says Lawrence Witmer, a paleontologist at Ohio University in Athens who was not involved in the study. “Charles Darwin couldn’t have scripted it any better.”

The next step is to determine if the braincase is typical of a mid-Cretaceous tyrannosaur, or just one oddball data point. “We’ve analyzed the heck out of each scrap of Bissekty tyrannosaur bone,” Brusatte says, “so the thing that could move us forward is the discovery of new specimens in other middle Cretaceous rock units in other parts of the world.”

Itty bitty engine puts a single atom to work

A team of scientists has built a heat engine out of a single atom.

Heat engines, like steam engines or internal combustion engines, convert heat into motion. To create the minuscule engine, physicist Johannes Roßnagel of University of Mainz and colleagues heated and cooled a calcium ion with an electric field and a laser, causing it to move and do a tiny amount of work. They report their results in the April 15 Science.

Read more about this and other scaled-down engines in “Ultrasmall engines bend second law of thermodynamics.”

Hubble telescope snaps stunning pic for its 26th birthday

Time to add another gorgeous space photo to the Hubble Space Telescope’s list of greatest hits. For the orbiting observatory’s 26th anniversary in space, astronomers snapped a picture of the Bubble Nebula, a seven-light-year-wide pocket of gas being blown away by a blazing massive star about 7,100 light-years away in the constellation Cassiopeia.

The star responsible for the bubble is young, just 4 million years old, and about 45 times as massive as our sun. It is so hot and bright that it launches its own gas into space at more than 6 million kilometers per hour. The vibrant colors in the nebula represent the elements oxygen, hydrogen and nitrogen.

Hubble launched April 24, 1990, aboard the space shuttle Discovery. A series of visits by astronauts have kept the aging telescope’s suite of cameras, spectrometers and ancillary equipment up-to-date and operating well into its third decade.

Leptospirosis bacterium still haunts swimming holes

Danger in ‘swimming hole’  — As warm weather approaches, the old swimming hole will again beckon boys and girls in farm areas. But disease germs lurk in waters exposed to cattle and other animals…. One “swimming hole disease” called leptospirosis is caused by water-borne Leptospira pomona…. Warm summer temperatures are ideal for maintaining leptospiral organisms in water, and heavy rains may transport the organisms downstream.  — Science News, May 14, 1966

An estimated 100 to 200 people get leptospirosis annually in the United States. The disease, which can cause fever, headache and vomiting, is most common in tropical and rural regions worldwide. Summertime swimming is also haunted by another single-celled terror that thrives in warm freshwater: the so-called “brain-eating” amoeba, Naegleria fowleri. The amoeba caused 35 reported infections in the United States from 2005 to 2014. If N. fowleri enters a person’s nose, it can travel to the brain, where swelling triggered by the immune system kills most victims (SN: 8/22/15, p. 14).

Despite misuses, statistics still has solid foundation

In many realms of science today, “statistical wisdom” seems to be in short supply. Misuse of statistics in scientific research has contributed substantially to the widespread “reproducibility crisis” afflicting many fields (SN: 4/2/16, p. 8; SN: 1/24/15, p. 20). Recently the American Statistical Association produced a list of principles warning against multiple misbeliefs about drawing conclusions from statistical tests. Statistician Stephen Stigler has now issued a reminder that there is some wisdom in the science of statistics. He identifes seven “pillars” that collectively provide a foundation for understanding the scope and depth of statistical reasoning.
Stigler’s pillars include methods for measuring or representing aggregation (measures, such as averages, that represent a collection of data); information (quantifying it and assessing how it changes); likelihood (coping with probabilities); intercomparison (involving measures of variation within datasets); regression (analyzing data to draw inferences); design (of experiments, emphasizing randomization); and residual (identifying the unexplained “leftovers” and comparing scientific models).

His approach is to identify the historical origins of these seven key pillars, providing some idea of what they are and how they can assist in making sense of numerical data. His explanations are engaging but not thorough (it’s not a textbook), and while mostly accessible, his writing often assumes a nontrivial level of mathematical knowledge. You’ll have to cope with expressions such as L(Θ)=L(Θ)|Χ and Cov(L,W)=E{Cov(L,W|S)}+Cov(E{L|S}, E{W|S}) every now and then.

While Stigler defends statistics from some of the criticisms against it — noting, for instance, that specific misuses should not be grounds for condemning the generic enterprise — he acknowledges that some issues are still a source of concern, especially in the new era of “big data” (SN: 2/7/15, p. 22). Using common statistical tests when many comparisons are made at once, or applying tests at multiple stages of an experimental process, introduces problems that the seven pillars do not accommodate. Stigler notes that there is room, therefore, for an eighth pillar. “The pillar may well exist,” he writes, “but no overall structure has yet attracted the general assent needed for recognition.”

Antibiotics in cattle leave their mark in dung

Overuse of antibiotics in livestock can spread drug-resistant microbes — via farm workers or even breezy weather. But there’s more than one reason stay upwind of drugged cattle.

Dung beetles (Aphodius fossor) make their living on cattle dung pats, which are rich in nutritious microbes. To investigate the effects of cattle antibiotics on this smaller scale, Tobin Hammer of the University of Colorado at Boulder and his colleagues studied the tiny communities around tetracycline-dosed and undosed cows. Compared with untreated cows’ dung, microbes in dung produced by treated cows were less diverse and dominated by a genus with documented resistance, the researchers report May 25 in the Proceedings of the Royal Society B.

Beetles typically reduce methane gas wafting off dung, but pats from treated cows showed a 1.8-fold increase in methane output. How this might figure into greater cattle methane production remains to be studied, but Hammer and company speculate that the antibiotics may wipe out the bacterial competition for microbial methane factories.

Tiny plastics cause big problems for perch, lab study finds

Editor’s note: On May 3, 2017, Science retracted the study described in this article. Based on findings from a review board at Uppsala University, Science cites three reasons for pulling the study: The experiments lacked ethical approval, the original data do not appear in the paper and questions emerged about experimental methods.

Microscopic pieces of plastic rule Earth’s oceans, with numbers in the billions — possibly trillions. These tiny plastic rafts provide homes to microbes (SN: 2/20/16, p. 20), but their ecological effects remain murky.
In a lab at Uppsala University in Sweden, researchers exposed European perch (Perca fluviatilis) larvae to a microplastic called polystyrene to see how they might react. The exposure triggered a slew of potentially negative effects: Fewer eggs hatched, growth rates dropped and feeding habits changed, with some larvae preferring polystyrene to more nutritious food options. Exposed larvae were also sluggish in responding to scents that signal approaching predators in the wild, the team reports in the June 3 Science.

European perch, a keystone species in the Baltic Sea, have recently experienced a population dive. Because the drop has been linked to juvenile feeding issues, the researchers argue that microplastics could be to blame.