Knowledge Update

​Washington, Feb 10 (IANS) NASA is set to open discussions about a study that has proposed a system capable of landing on Jupiter's icy moon Europa in search for life beyond Earth.

The study that NASA commissioned last year to assess the science value and engineering design of a future Europa lander mission submitted its report this week.

The report listed three science goals for the mission - the primary being search for evidence of life on Europa, the US space agency said.

The other goals are to assess the habitability of Europa by directly analysing material from the surface and to characterise the surface and subsurface to support future robotic exploration of Europa and its ocean. 

The report also described some of the notional instruments that could be expected to perform measurements in support of these goals.

To discuss the report and receive feedback from the wider science community, NASA announced two upcoming meetings scheduled for March and April.

Europa, slightly smaller than Earth's moon, is widely believed by scientists to be having a global saltwater ocean beneath its icy crust. 

This ocean has at least twice as much water as Earth's oceans. 

While recent discoveries have shown that many bodies in the solar system either have subsurface oceans now, or may have had in the past, Europa is one of only two places where the ocean is understood to be in contact with a rocky seafloor (the other being Saturn's moon Enceladus). 

This rare circumstance makes Europa one of the highest priority targets in the search for present-day life beyond Earth.

The team for this study was tasked with developing a life-detection strategy in Europa, a first for a NASA mission since the Mars Viking mission era more than four decades ago. 

The report makes recommendations on the number and type of science instruments that would be required to confirm if signs of life are present in samples collected from the icy moon's surface.

The team also worked closely with engineers to design a system capable of landing on a surface about which very little is known. 

Given that Europa has no atmosphere, the team developed a concept that could deliver its science payload to the icy surface without the benefit of technologies like a heat shield or parachutes, NASA said.

​Washington, Feb 10 (IANS) NASA said its OSIRIS-REx spacecraft has started a two-week search for an enigmatic class of near-Earth objects known as Earth-Trojan asteroids.

The mission, currently on a two-year outbound journey to the asteroid Bennu, will spend almost two weeks searching for evidence of these small bodies, the US space agency said on Thursday. 

Although scientists have discovered thousands of Trojan asteroids accompanying other planets, only one Earth-Trojan has been identified to date, asteroid 2010 TK7. 

Scientists predict that there should be more Trojans sharing Earth's orbit but they are difficult to detect from Earth as they appear near the sun on the Earth's horizon.

"So this search gives us a unique opportunity to explore the primordial building blocks of Earth," said principal investigator Dante Lauretta of the University of Arizona, Tucson.

Trojan asteroids are trapped in stable gravity wells, called Lagrange points, which precede or follow a planet. 

Launched on September 8, 2016, OSIRIS-REx is currently travelling through Earth's fourth Lagrange point, which is located 60 degrees ahead in Earth's orbit around the sun, about 150 million km from Earth. 

The mission team will use this opportunity to take multiple images of the area with the spacecraft's MapCam camera in the hope of identifying Earth-Trojan asteroids in the region.

"Because the Earth's fourth Lagrange point is relatively stable, it is possible that remnants of the material that built Earth are trapped within it," Lauretta said. 

The operations involved in searching for Earth-Trojan asteroids closely resemble those required to search for natural satellites and other potential hazards around Bennu when the spacecraft approaches its target in 2018, NASA said.

​Washington, Feb 10 (IANS) NASA said its OSIRIS-REx spacecraft has started a two-week search for an enigmatic class of near-Earth objects known as Earth-Trojan asteroids.

The mission, currently on a two-year outbound journey to the asteroid Bennu, will spend almost two weeks searching for evidence of these small bodies, the US space agency said on Thursday. 

Although scientists have discovered thousands of Trojan asteroids accompanying other planets, only one Earth-Trojan has been identified to date, asteroid 2010 TK7. 

Scientists predict that there should be more Trojans sharing Earth's orbit but they are difficult to detect from Earth as they appear near the sun on the Earth's horizon.

"So this search gives us a unique opportunity to explore the primordial building blocks of Earth," said principal investigator Dante Lauretta of the University of Arizona, Tucson.

Trojan asteroids are trapped in stable gravity wells, called Lagrange points, which precede or follow a planet. 

Launched on September 8, 2016, OSIRIS-REx is currently travelling through Earth's fourth Lagrange point, which is located 60 degrees ahead in Earth's orbit around the sun, about 150 million km from Earth. 

The mission team will use this opportunity to take multiple images of the area with the spacecraft's MapCam camera in the hope of identifying Earth-Trojan asteroids in the region.

"Because the Earth's fourth Lagrange point is relatively stable, it is possible that remnants of the material that built Earth are trapped within it," Lauretta said. 

The operations involved in searching for Earth-Trojan asteroids closely resemble those required to search for natural satellites and other potential hazards around Bennu when the spacecraft approaches its target in 2018, NASA said.

​Toronto, Feb 10 (IANS) Researchers have found a way to create three dimensional (3-D) heart tissue that beats in synchronised harmony which could lead to better understanding of cardiac health and improved treatments.

"This breakthrough will allow better and earlier drug testing, and potentially eliminate harmful or toxic medications sooner," said one of the researchers Muhammad Yousaf, Professor at York University in Toronto, Canada.

Until now, most 2-D and 3-D in-vitro tissue did not beat in harmony and required scaffolding for the cells to hold onto and grow, causing limitations. 

In this research, published in the journal Scientific Reports, Yousaf and his team made a scaffold free beating tissue out of three cell types found in the heart -- contractile cardiac muscle cells, connective tissue cells and vascular cells.

The researchers believe this is the first 3-D in vitro cardiac tissue with three cell types that can beat together as one entity rather than at different intervals.

In addition, the substance used to stick cells together (ViaGlue) could provide researchers with tools to create and test 3D in vitro cardiac tissue in their own laboratories to study heart disease and issues with transplantation. 

Cardiovascular associated diseases are the leading cause of death globally.

"Making in vitro 3-D cardiac tissue has long presented a challenge to scientists because of the high density of cells and muscularity of the heart," Dmitry Rogozhnikov, a chemistry PhD student at York University. 

"For 2-D or 3-D cardiac tissue to be functional it needs the same high cellular density and the cells must be in contact to facilitate synchronised beating," Rogozhnikov explained.

Although the 3-D cardiac tissue was created at a millimetre scale, larger versions could be made, said Yousaf, who has created a start-up company OrganoLinX to commercialise the ViaGlue reagent and to provide custom 3D tissues on demand.

Sydney, Feb 10 (IANS) A new ultra-low dose four-in-one pill that is 100 per cent effective in lowering high blood pressure has been developed by Australian researchers.

Hypertension or high blood pressure -- which affects around 1.1 billion people worldwide -- is one of the major risk factors for heart attack, stroke, dementia and kidney disease.

Researchers from the University of Sydney in Australia, prescribed a quadpill -- a single capsule containing four of the most commonly used blood pressure-lowering drugs each at a quarter dose (irbesartan 37·5 mg, amlodipine 1·25 mg, hydrochlorothiazide 6·25 mg, and atenolol 12·5 mg) -- or a placebo to 18 patients in Sydney over four weeks. 

The results, published in The Lancet medical journal, revealed that 100 per cent of patients on trial saw their blood levels dropping below 140 over 90, whereas just 33 per cent of patients on the placebo could achieve this rate.

"Most people receive one medicine at a normal dose but that only controls blood pressure about half the time. In this small trial, blood pressure control was achieved for everyone," said Clara Chow, Professor at the University of Sydney in Australia. 

Patients who consume the commonly available hypertension-lowering drugs experience side-effects which can vary from swollen ankles to kidney abnormalities depending on the type of class of the drug.

However, the new pill has no such side-effects, the researchers said.

"We know that high blood pressure is a precursor to stroke, diabetes and heart attack. The need for even lower blood pressure levels has been widely accepted in the last few years. So this could be an incredibly important step in helping to reduce the burden of disease globally," Chow added.

New Delhi, Feb 10 (IANS) WhatsApp on Friday rolled out a two-step verification process for all devices to enhance the security of users' accounts.

WhatsApp has been working on two-step verification for the past several months.

​New York, Feb 10 (IANS) Twitter has grown by two million monthly active users in the fourth quarter, finishing the year with 319 million worldwide, media reports said.

According to a report in Recode on Thursday, the spectacle of the US presidential election was Twitter's best material in years, and made the service a crucial source for direct

Mexico City, Feb 10 (IANS) Mexico's central bank raised the benchmark interest rate to 6.25 per cent, the highest since April 2009, to curb inflation, the media reported.

Inflation began to rise in October to close 2016 at 3.36 per cent, and rose to 4.72 per cent in January, Xinhua news agency reported.

New York, Feb 10 (IANS) Scientists using NASA's Hubble space telescope have discovered a white dwarf star whose atmosphere is rich in materials that are the basic building blocks for life -- carbon, nitrogen, as well as oxygen and hydrogen, the components of water.

The white dwarf is approximately 200 light years from the Earth and is located in the constellation Bootes, said the study.

White dwarf stars are dense, burned-out remnants of normal stars.

The study presents evidence that the planetary system associated with the white dwarf contains materials that are the basic building blocks for life, said study co-author Benjamin Zuckerman, Professor at University of California, Los Angeles. 

And although the study focused on this particular star -- known as WD 1425+540 -- the fact that its planetary system shares characteristics with our solar system strongly suggests that other planetary systems would also.

"The findings indicate that some of life's important preconditions are common in the universe," Zuckerman said.

Many scientists believe the Earth was dry when it first formed, and that the building blocks for life on our planet -- carbon, nitrogen and water -- appeared only later as a result of collisions with other objects in our solar system that had those elements.

The research, published in the Astrophysical Journal Letters, described how the white dwarf came to obtain carbon, nitrogen, oxygen and hydrogen. 

The scientists reported that a minor planet in the planetary system was orbiting around the white dwarf, and its trajectory was somehow altered, perhaps by the gravitational pull of a planet in the same system. 

That change caused the minor planet to travel very close to the white dwarf, where the star's strong gravitational field ripped the minor planet apart into gas and dust. 

Those remnants went into orbit around the white dwarf -- much like the rings around Saturn, Zuckerman said -- before eventually spiraling onto the star itself, bringing with them the building blocks for life.

The researchers think these events occurred relatively recently, perhaps in the past 100,000 years or so.

This was the first time that nitrogen was detected in the planetary debris that falls onto a white dwarf, said Siyi Xu of the European Southern Observatory in Garching, Germany.

"Nitrogen is a very important element for life as we know it," Xu, who led the team that made the discovery, explained. 

"This particular object is quite rich in nitrogen, more so than any object observed in our solar system," Xu said.