Knowledge Update

​New York, April 27 (IANS) Early humans probably reached North America 130,000 years ago -- 115,000 years earlier than previously thought, claims a study.

Birmingham, April 25 (IANS) Higher level of autonomy at workplace has a positive effect on employees' well-being and gives them job satisfaction, according to a research.

Researchers at the University of Birmingham Business School examined the changes in reported well-being relative to levels of autonomy using two separate years of data for 20,000 employees from the Understanding Society survey.

The research, published in the journal Work and Occupations, found that levels of autonomy differed considerably between occupations and by gender.

Those working in management reported the highest levels of autonomy in their work, with 90 per cent reporting "some" or "a lot" of autonomy in the workplace.

Professionals report much less autonomy, particularly over the pace of work and over their working hours, according to the survey. 

For other employees -- 40-50 per cent of those surveyed -- experienced much lower autonomy while around half of lower-skilled employees experience no autonomy over working hours at all.

Dr Daniel Wheatley at the University of Birmingham Business School said: "Greater levels of control over work tasks and schedule have the potential to generate significant benefits for the employee, which was found to be evident in the levels of reported well-being."

"The positive effects associated with informal flexibility and working at home, offer further support to the suggestion that schedule control is highly valued and important to employees 'enjoying' work," he said.

The study found "compelling" evidence to suggest that men and women were affected in different ways by the type of autonomy they experienced.

For women, flexibility over the timing and location of their work appeared to be more beneficial allowing them to balance other tasks such as family commitments.

Dr Wheatley added: "The manner of work and control over work schedule was found to be more relevant to the well-being of female employees."

"Flexibility in work location, specifically homeworking, benefitted women with caring responsibilities allowing them to better manage paid work alongside the household," he said.

Men were found to be more impacted by job tasks, pace of work and task order.

The research also highlighted that despite the reported increased levels of well-being, in many cases managers remain unwilling to offer employees greater levels of autonomy and the associated benefits.

​London, April 24 (IANS) A consortium of British companies on Monday unveiled a plan to test driverless cars on UK roads and motorways in 2019, the media reported.

The Driven consortium led by Oxbotica, which makes software for driverless vehicles, also plans to try out a fleet of autonomous vehicles between London and Oxford, the BBC reported.

The cars will communicate with one another about any hazards and should operate with almost full autonomy -- but will have a human on board as well.

Previous tests of driverless vehicles in the UK have mainly taken place at slow speeds and not on public roads.

"We're moving from the singleton autonomous vehicle to fleets of autonomous vehicles -- and what's interesting is what data the vehicles share with one another, when, and why," the BBC quoted founder Paul Newman, a professor from Oxford University, as saying. 

The project is backed by a government grant of 8.6 million pounds ($11 million) and involves an insurance company which will assess the risks involved at each stage of the journey.

NASA astronaut Peggy Whitson breaks US spaceflight record

Beijing, April 23 (IANS) A set of bamboo slips dating back more than 2,300 years were officially recognised on Sunday by the Guinness World Records as the world's earliest decimal calculation tool.

"The significance is that it's decimal, not duodecimal as seen in other countries. Decimal did not appear in Europe until the 15th century," Xinhua news agency quoted head of the Research and Conservation Centre for Excavated Texts of Beijing-based Tsinghua University Li Xueqin as saying.

The 21 slips, crafted around 305 BC during the Warring States period, are each 43.5 centimetres long and 1.2 centimetres wide.

When arranged together as a multiplication table, the slips can perform multiplication and division of any two whole numbers under 100 and numbers containing the fraction 0.5.

The slips have inscribed numbers and holes, where threads used to go. A user would pull the threads corresponding to numbers needed to be calculated in order to see the result.

The owner of the slips remains unknown, according to Li. "Our guess is that the tool might be used in trade, or measurement of land in the kingdom of Chu."

In July 2008, Tsinghua acquired a rare collection of 2,500 bamboo slip items from the late Warring States period, which had been smuggled out of China, including the multiplication table.

​New York, April 23 (IANS) Researchers have developed thin carbon nanotube (CNT) textiles that exhibit high electrical conductivity and a level of toughness about 50 times higher than copper films, currently being used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics, including biological and structural health monitoring sensors," said Sameh Tawfick from the College of Engineering at University of Illinois. 

Aligned carbon nanotube sheets are suitable for a wide range of application spanning from the micro to the macro-scales, Tawfick noted in the study published in the journal Advanced Engineering Materials. 

"The study of the fracture energy of CNT textiles led us to design these extremely tough films. Tough nano-architectured conductive textile made by capillary plicing of Ccrbon nanotubes," said lead author Yue Liang. 

Beginning with catalyst deposited on a silicon oxide substrate, vertically aligned carbon nanotubes were synthesised via chemical vapour deposition in the form of parallel lines of 5 micrometre wide, 10 micrometre in length, and 20-60 micrometre in heights.

"Looking for ways to staple the CNTs together, we were inspired by the splicing process developed by ancient Egyptians 5,000 years ago to make linen textiles," Liang added.

The new CNT textile, with simple flexible encapsulation in an elastomer matrix, can be used in smart textiles, smart skins and a variety of flexible electronics. 

Owing to their extremely high toughness, they represent an attractive material, which can replace thin metal films to enhance device reliability.

​London, April 23 (IANS) A team of engineers has developed a process by which it is now possible to 3D print complex forms of glass.

The scientists at the Germany-based Karlsruhe Institute of Technology (KIT) mixed nanoparticles of high-purity quartz glass and a small quantity of liquid polymer and allow this mixture to be cured by light at specific points by means of stereolithography.

The material, which has remained liquid, is washed out in a solvent bath, leaving only the desired cured structure. The polymer still mixed in this glass structure is subsequently removed by heating.

"The shape initially resembles that of a pound cake; it is still unstable, and therefore the glass is sintered in a final step, that is, heated so that the glass particles are fused," said Bastian E. Rapp from KIT Institute of Microstructure Technology.

The scientists presented the method in the journal Nature.

"We present a new method, an innovation in materials processing, in which the material of the piece manufactured is high-purity quartz glass with the respective chemical and physical properties," added Rapp.

The glass structures made by the KIT scientists show resolutions in the range of a few micrometers -- one micrometer corresponding to one thousandth of a millimeter.

3D-formed glass can be used in data technology.

​Sydney, April 22 (IANS) Homo floresiensis, a species of tiny human discovered on the Indonesian island of Flores in 2003, most likely evolved from an ancestor in Africa and not from Homo erectus - an ancestor to modern humans - as has been widely believed, a study says.

The researchers believe that their findings, published in the Journal of Human Evolution, should help put to rest a hotly contested debate about the origin of Homo floresiensis.

"We can be 99 per cent sure it's not related to Homo erectus and nearly 100 per cent chance it isn't a malformed Homo sapiens," said Mike Lee of Australia's Flinders University and the South Australian Museum.

Homo floresiensis, dubbed "the hobbits" due to their small stature, were most likely a sister species of Homo habilis -- one of the earliest known species of human found in Africa 1.75 million years ago, the study said.

Data from the study concluded there was no evidence for the popular theory that Homo floresiensis evolved from the much larger Homo erectus, the only other early hominid known to have lived in the region with fossils discovered on the Indonesian mainland of Java.

"The analyses show that on the family tree, Homo floresiensis was likely a sister species of Homo habilis. It means these two shared a common ancestor," said study leader Debbie Argue of the Australian National University.

"It's possible that Homo floresiensis evolved in Africa and migrated, or the common ancestor moved from Africa then evolved into Homo floresiensis somewhere," Argue said.

Homo floresiensis is known to have lived on Flores until as recently as 54,000 years ago.

Where previous research had focused mostly on the skull and lower jaw, this study used 133 data points ranging across the skull, jaws, teeth, arms, legs and shoulders.

None of the data supported the theory that Homo floresiensis evolved from Homo erectus, Argue said.

"We looked at whether Homo floresiensis could be descended from Homo erectus," she said.

"We found that if you try and link them on the family tree, you get a very unsupported result. All the tests say it doesn't fit -- it's just not a viable theory," Argue said.

This was supported by the fact that in many features, such as the structure of the jaw, Homo floresiensis was more primitive than Homo erectus, she added.

​New York, April 22 (IANS) A team of scientists has developed a method to increase the performance of high-power electrical storage devices and, at the same time, decrease their size.

The researchers from Stanford School of Earth, Energy and Environmental Sciences describe a mathematical model for designing new materials for energy storage to reduce carbon emissions in the transportation and electricity sectors.

"The potential here is that you could build batteries that last much longer and make them much smaller," said study co-author Daniel Tartakovsky. 

"If you could engineer a material with a far superior storage capacity than what we have today, then you could dramatically improve the performance of batteries," added Tartakovsky.

One of the primary obstacles to transitioning from fossil fuels to renewables is the ability to store energy for later use, such as during hours when the sun is not shining in the case of solar power. 

Demand for cheap, efficient storage has increased as more companies turn to renewable energy sources, which offer significant public health benefits.

Tartakovsky hopes the new materials developed through this model will improve supercapacitors, a type of next-generation energy storage that could replace rechargeable batteries in high-tech devices like cellphones and electric vehicles. 

"We developed a model that would allow materials chemists to know what to expect in terms of performance if the grains are arranged in a certain way, without going through these experiments," Tartakovsky said in a paper published in the journal Applied Physics Letters. 

"This framework also shows that if you arrange your grains like the model suggests, then you will get the maximum performance," Tartakovsky added.

Beijing, April 22 (IANS) China's first spacecraft, the Tianzhou-1, docked successfully with the orbiting Tiangong-2 space lab on Saturday, according to Beijing Aerospace Control Centre.

Tianzhou-1, which was launched on Thursday evening from Wenchang Space Launch Centre in Hainan province, began to approach Tiangong-2 automatically at 10.02 a.m., and made contact with at 12.16 p.m., the People's Daily reported.

The Tianzhou-1 cargo ship and Tiangong-2 space lab will have another two dockings.

The second docking will be conducted from a different direction, which aims to test the ability of the cargo ship to dock with a future space station from different directions.

In the third docking, Tianzhou-1 will use fast-docking technology. 

It normally takes about two days to dock, while fast docking will take only six hours.

Refuelling will also be conducted, a process with 29 steps that takes several days.

Tiangong-2, which went into space on September 15, 2016, is China's first space lab "in the strict sense" and a key step in building a permanent space station by 2022.

Cargo ships play a crucial role maintaining a space station and carrying supplies and fuel into orbit.