Knowledge Update

​London, Dec 25 (IANS) Using ultrafast imaging of moving energy, scientists have determined the speed of photosynthesis.

The study said the imaging could help scientists better understand the process and how it could be copied for producing fuels.

Earlier, it was believed that the process of charge separation in the reaction was the slowest step in the process. But scientists have shown that the slowest step is in fact the process through which the plants harvest light and transfer its energy through the antennae to the reaction centre.

"We can now see how nature has optimised the physics of converting light energy to fuel, and can probe this process using our new technique of ultrafast crystal measurements," said Jasper van Thor from Imperial College, London.

"For example, is it important that the bottleneck occurs at this stage, in order to preserve overall efficiency? Can we mimic it or tune it to make artificial photosynthesis more efficient? These questions, and many others, can now be explored," Thor added.

Scientists used lasers to cause reactions in crystals of Photosystem II -- enzyme that uses the light energy to split water into oxygen and hydrogen -- and then measured in space and time the movement of excitations of electrons.

"The resulting movie of the movement of excited electrons across minute sections of the system revealed where energy is held and when it is passed along," the study noted.

The study was published in the journal Nature Communications.

​New York, Dec 25 (IANS) When exposed to cancer treatment like chemotherapy and radiation, brain and heart tissues in very young children are more prone to apoptosis or programmed cell death, researchers said.

Apoptosis, in which molecular signals order cells to self-destruct, plays an important role in deciding the "fate" of a developing cell.

These toxic treatment stressors put young children at high risk for developing severe, long-lasting impairments in their brain, heart, the study said.

But active apoptosis in the early brain "also sets the stage for extremely high sensitivity to any type of damage or stress, especially that induced by radiation or chemotherapy," said lead author Kristopher A. Sarosiek, Assistant Professor at the Harvard T.H. Chan School of Public Health.

While some cancer cells die through apoptosis, some escape the death orders by activating "pro-survival" signals.

Anthony Letai from Dana-Farber Cancer Institute in Massachusetts, developed a test called BH3 profiling that can measure inside any cell the relative dominance of pro-survival or pro-death signals.

A cancer cell in which apoptotic death signals are dominant, is said to be "highly primed" or ready for self-destruction and therefore easily killed by therapy, while a cell with low priming is more resistant to death or damage.

Measuring the priming of cells in normal cells and tissues, the researchers found that in most normal adult tissues, including the brain and the heart, the machinery needed to perform apoptosis is nearly completely absent.

In contrast, this molecular machinery is abundant in newborn and very young rodents. As a result, brain and heart cells were therefore much more vulnerable to undergoing cell death when exposed to chemotherapy or radiation.

When tested in human cells, the youngest human brain cells were more highly primed with apoptotic machinery and vulnerable to chemotherapy and radiation damage.

Human brain and heart cells are most highly primed for apoptosis until four to six years of age, after which priming continues to be reduced, the researchers noted, in the paper appearing in the journal Cancer Cell.

New York, Dec 25 (IANS) Driverless cars can save fuel if they trail each other in large platoons, as they will experience less aerodynamic drag when they drive close together, researchers have found.

But formation of a vehicle platoon could be time consuming.

The study by the researchers at Massachusetts Institute of Technology (MIT) that was recently presented at the International Workshop on the Algorithmic Foundations of Robotics suggested that relatively simple, straightforward schedules may be the optimal approach for saving fuel and minimising delays for autonomous vehicle fleets.

The findings may also apply to conventional long-distance trucking and even ride-sharing services.

"Ride-sharing and truck platooning and even flocking birds and formation flight, are similar problems from a systems point of view," said Sertac Karaman, Associate Professor at MIT.

"People who study these systems only look at efficiency metrics like delay and throughput. We look at those same metrics, versus sustainability such as cost, energy, and environmental impact. This line of research might really turn transportation on its head," Karaman added.

The research noted that for truck-driving -- particularly over long distances -- most of a truck's fuel is spent on trying to overcome aerodynamic drag, that is, to push the truck through the surrounding air.

"Scientists have previously calculated that if several trucks were to drive just a few metres apart, one behind the other, those in the middle should experience less drag, saving fuel by as much as 20 per cent, while the last truck should save 15 per cent -- slightly less, due to air currents that drag behind," the study found.

As the number of vehicles are increased in the platoon, more energy can be collectively saved but it may cost in terms of time it takes to form a platoon.

The study found that the simplest policies resulted in least delays in platoon formation while saving most fuel.

"Time tables set to deploy platoons at regular intervals were more sustainable and efficient than those that deployed at more staggered times," the study mentioned.

​Brussels, Dec 24 (IANS) The European Union (EU) has provided 38.2 million euros ($39.8 million) in emergency funding to Italy to ease migratory pressure, an EU statement said.

​Beijing, Dec 24 (IANS) China began construction of its first high-speed railway network line under a private-public partnership, officials reported on Saturday.

The 269 km line will connect Hangzhou and Taizhou, in the eastern province of Zhejiang, among China's most prosperous provinces and one where the private sector is

​Beijing, Dec 24 (IANS) After 28 years of talks between Beijing and Moscow, construction has finally started on a modern highway bridge connecting China and Russia across the Heilongjiang river, the first between the two countries.

​San Francisco, Dec 24 (IANS) Amid the escalating patents row with Finnish smartphone maker Nokia, Apple has reportedly pulled all products made by Withings -- a French company and now a Nokia subsidiary -- from Apple Stores, be it online or retail. Several Withings iOS-compatible products -- mostly health-related connected accessories -- have been available at Apple Stores for nearly two years as part of a retail alliance, AppleInsider reported on Saturday. The Withings product sales continued even after the company was acquired by Nokia in April for nearly $190 million. The Withings brand was integrated into Nokia's Digital Health unit. "Now, the devices made by the Nokia subsidiary are no longer listed on Apple's website. Previously, Apple carried a wide range of iOS-compatible Withings devices in its retail stores, including the 'Body Cardio Scale' and 'Wireless Blood Pressure Monitor,'" the report added. Five years after Apple and Nokia settled a lawsuit, the tech giants have again locked horns over patents with Apple filing an anti-trust lawsuit against third-party companies Patent Assertion Entities (PAEs) that act on Nokia's behalf, and the Finland-based firm suing Apple directly earlier this week. Nokia filed a suit in Europe and the US, claiming Apple is still infringing on Nokia patents. The lawsuit covers 32 patents, including display, user interface, software and video-coding technology. Nokia said that since settling the initial case, Apple has "declined subsequent offers made by Nokia to license other [parts] of its patented inventions, which are used by many Apple products." In its lawsuit, Apple argued that Nokia already has agreements to license its patents for fair and reasonable terms, also know as "FRAND" (Fair, Reasonable, and Non-Discriminatory). "But Nokia is transferring these patents to PAEs in order to aggressively pursue money," Apple argued. According to the Cupertino-based tech giant, Nokia has been conspiring with PAEs patent assertion entities (Acacia Research and Conversant Property Management) in an "illegal patent transfer scheme" to wring money out of Apple because Nokia's cell phone business is failing. According to the AppleInsider report, Apple has now "expunged all mention of Withings and its product line from the Apple.com online retail database". "Whether or not the recent Withings removal is related to Nokia's shady legal dealings has yet to be confirmed, but Apple has in the past used its retail might as a retaliatory weapon," the report added. In 2011, the two companies settled a patent fight over smartphone technology through a licensing agreement that committed Apple to make a one-time payment to the company and to pay regular royalties in the future, media reported. The companies also agreed to withdraw complaints against each other with the International Trade Commission over the use of intellectual property.

​New York, Dec 24 (IANS) Studying a diverse group of solitary, desert bees, researchers have reported identification of nine new species of the genus Perdita, including two ant-like males.

These solitary bees are not major pollinators of agricultural crops, but fill an important role in natural ecosystems of the American Southwest, including the sizzling sand dunes of California's Death Valley.

In a study published in the journal Zootaxa, the researchers described curious ant-like males of two of the species, which are completely different in appearance from their mates.

"It's unclear why these males have this unique form, but it could indicate they spend a lot of time in the nest," said entomologist Zach Portman from Utah State University in the US.

"We may find more information as we learn more about their nesting biology," Portman noted.

Portman tracked the tiny elusive bees by watching for their buzzing shadows in the blinding, midday sunlight the diminutive insects tend to favour.

"Their activity during the hottest part of the day may be a way of avoiding predators," Portman said.

"They appear to be important pollinators of desert plants commonly known as 'Crinklemats'" Portman explained.

Crinklemats, flowering plants of the genus Tiquilia, grow low to the ground and feature ridged, hairy leaves and small, trumpet-shaped blue blossoms.

"Like the bees, Tiquilia flowers are very small," Portman said. 

"The bees must squeeze into the long, narrow corollas and dunk their heads into the flowers to extract the pollen," he added.

The scientists reported that the female bees use pollen collected from the flowers to build up a supply to nourish their young. 

Once they have completed a pollen provision, the bees lay their eggs on the stash and leave their offspring to fend for themselves.

Though declines in bee populations have heightened awareness of the importance of pollinating insects to the world's food supply, numerous bee species remain undescribed or poorly understood, the researchers pointed out.

New York, Dec 24 (IANS) Researchers have found that centuries-old herbal medicine, discovered by Chinese scientists to treat malaria, can aid in tuberculosis (TB) treatment and even slow drug resistance.

One-third of the world's population is infected with TB, which killed 1.8 million people in 2015, according to the Centers for Disease Control and Prevention.

Mycobacterium tuberculosis (Mtb) -- the TB-causing bacteria -- needs oxygen to thrive in the body and the immune system starves this bacterium of oxygen to control the infection. 

The study found that artemisinin -- the ancient remedy -- stopped the ability Mtb to become dormant -- a stage of the disease that often makes the use of antibiotics ineffective.

"When TB bacteria are dormant, they become highly tolerant to antibiotics. Blocking dormancy makes the TB bacteria more sensitive to these drugs and could shorten treatment times," said Robert Abramovitch, Assistant Professor at Michigan State University in the US.

Artemisinin attacks a molecule called heme, which is found in the Mtb oxygen sensor. 

By disrupting this sensor and essentially turning it off, the medicine stopped the disease's ability to sense how much oxygen it was getting, the researchers said.

"When the Mtb is starved of oxygen, it goes into a dormant state, which protects it from the stress of low-oxygen environments. If Mtb can't sense low oxygen, then it can't become dormant and will die," Abramovitch said. 

TB takes up to six months to treat and is one of the main reasons the disease is so difficult to control, the researchers said.

They also said that the finding could be key to shortening the course of therapy because it can clear out the dormant, hard-to-kill bacteria.

The paper was published in the journal Nature Chemical Biology.

​London, Dec 24 (IANS) Our decision-making is heavily influenced by the world around us, a study has found, challenging the traditional idea that thinking takes place strictly in the head.

The idea that thinking is done only in the head is a convenient illusion that doesn't reflect how problems are solved in reality, said Gaelle Vallee-Tourangeau, Professor at Kingston University in Britain.

"When you write or draw, the action itself makes you think differently. In cognitive psychology you are trained to see the mind as a computer, but we've found that people don't think that way in the real world. 

"If you give them something to interact with they think in a different way," Vallee-Tourangeau added.

In the study, the researchers explored how maths anxiety -- a debilitating emotional reaction to mental arithmetic that can lead sufferers to avoid even simple tasks like splitting a restaurant bill -- could potentially be managed through interactivity.

The study involved asking people to speak a word repeatedly while doing long sums at the same time. 

The results showed that the mathematical ability of those asked to do the sums in their heads was more affected than those given number tokens that they could move with their hands.

"We found that for those adding the sums in their head, their maths anxiety score predicted the magnitude of errors made while speaking a word repeatedly. If they're really maths anxious, the impact will be huge," Vallée-Tourangeau explained. 

"But in a high interactivity context -- when they were moving number tokens -- they behaved as if they were not anxious about numbers," Vallée-Tourangeau said.

Understanding how we think and make decisions by interacting with the world around us could help businesses find new ways of improving productivity -- and even improve people's chances of getting a job, the researches noted.

The study was published in the journal Cognitive Research: Principles and Implications.