Astronomy
ExoMars 2016 Orbiter And Lander Mated For March Launch
Earth’s lone mission to the Red Planet this year has now been assembled into launch configuration and all preparations are currently on target to support blastoff from Baikonur at the opening of the launch window on March 14, 2016.
The ambitious ExoMars 2016 mission is comprised of a pair of European spacecraft named the Trace Gas Orbiter (TGO) and the Schiaparelli lander, built and funded by the European Space Agency (ESA).
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“The main objectives of this mission are to search for evidence of methane and other trace atmospheric gases that could be signatures of active biological or geological processes and to test key technologies in preparation for ESA’s contribution to subsequent missions to Mars,” says ESA.
After launch the pair will remain joined for the seven month long interplanetary journey to Mars until 16 October, at which time the Schiaparelli entry, descent and landing (EDL) demonstrator module will separate from the orbiter.
Three days later on October 19, TGO is slated to enter Mars orbit and Schiaparelli will begin its plummet through the thin Martian atmosphere and hoped for soft landing.
Mysterious Radio Burst Pinpointed In Distant Galaxy
Since 2007, astronomers have detected curious bright blasts of radio waves from the cosmos, each lasting no more than a few milliseconds. Now scientists have been able to pinpoint the source of one of these pulses: a galaxy 1.9 billion parsecs (6 billion light years) away. It probably came from two colliding neutron stars, says astronomer Evan Keane, a project scientist for the Square Kilometre Array (SKA). Keane, who works at the SKA Organization's headquarters at Jodrell Bank Observatory outside Manchester, UK, led the team that reports the detection in Nature.
The discovery is the “measurement the field has been waiting for”, says astronomer Kiyoshi Masui of the University of British Columbia in Vancouver, Canada. By finding more such fast radio bursts (FRBs) and measuring the distance to their source, astronomers hope to use the signals as beacons to shed light on the evolution of the Universe.
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Now that Keane and his team know the distance to the new FRB, they can use the length of the signal to reveal how much material it passed through. This could solve a longstanding mystery: precise measurements of the cosmic microwave background — the afterglow of the Big Bang — suggest that around 4% of the observable Universe today should be composed of ordinary matter (not dark energy or dark matter). But after totting up what they can see, researchers say around half that matter remains unaccounted for.
The amount of signal smearing from the team’s FRB indicates that the ‘missing’ matter is indeed there, Keane's team now report. Future bursts detected all around the sky could be used as probes to map that matter in detail. A similar approach could yield a map of the magnetic fields between galaxies, as they alter the bursts’ polarization signature in detectable ways.
Biology
Bat Super Immunity To Lethal Disease Could Help Protect People
[L]eading bat immunologist at CSIRO's Australian Animal Health Laboratory Dr Michelle Baker said.
"We focused on the innate immunity of bats, in particular the role of interferons - which are integral for innate immune responses in mammals - to understand what's special about how bats respond to invading viruses.
"Interestingly we have shown that bats only have three interferons which is only a fraction - about a quarter - of the number of interferons we find in people.
"This is surprising given bats have this unique ability to control viral infections that are lethal in people and yet they can do this with a lower number of interferons."
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"Unlike people and mice, who activate their immune systems only in response to infection, the bats interferon-alpha is constantly 'switched on' acting as a 24/7 front line defence against diseases," Dr Baker said.
"In other mammalian species, having the immune response constantly switched on is dangerous - for example it's toxic to tissue and cells - whereas the bat immune system operates in harmony."
Mucosal Immunoglobulins At Respiratory Surfaces Mark An Ancient Association That Predates The Emergence Of Tetrapods
Abstract:
Gas-exchange structures are critical for acquiring oxygen, but they also represent portals for pathogen entry. Local mucosal immunoglobulin responses against pathogens in specialized respiratory organs have only been described in tetrapods. Since fish gills are considered a mucosal surface, we hypothesized that a dedicated mucosal immunoglobulin response would be generated within its mucosa on microbial exposure. Supporting this hypothesis, here we demonstrate that following pathogen exposure, IgT+ B cells proliferate and generate pathogen-specific IgT within the gills of fish, thus providing the first example of locally induced immunoglobulin in the mucosa of a cold-blooded species. Moreover, we demonstrate that gill microbiota is predominantly coated with IgT, thus providing previously unappreciated evidence that the microbiota present at a respiratory surface of a vertebrate is recognized by a mucosal immunoglobulin. Our findings indicate that respiratory surfaces and mucosal immunoglobulins are part of an ancient association that predates the emergence of tetrapods.
Chemistry
Insect Sugar Could Treat Fatty Liver Disease
Cells in the body sometimes need a spring cleaning to clear out unwanted or dysfunctional proteins, fats, and other biomolecules cluttering their insides.
The regulated cleaning process cells use is called autophagy. Scientists think compounds that can trigger autophagy could lead to therapeutics for a range of diseases, including diabetes and Alzheimer’s disease, which involve the buildup of malfunctioning molecules in cells.
In a new study, researchers report that the disaccharide trehalose initiates autophagy by blocking glucose from entering cells. They show that trehalose can help liver cells in mice remove excess fat, preventing fatty liver disease in the animals.
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Several studies have shown that the disaccharide can trigger autophagy to help neurons clear out aggregated proteins in mouse models of neurodegenerative diseases such as Alzheimer’s and amyotrophic lateral sclerosis. If trehalose could get cells to flush out built-up proteins, DeBosch and his team thought, maybe it would also help eliminate excess fat.
To test the idea, they had a group of mice drink a 3% trehalose solution for two days before putting the rodents on a diet that can induce fatty liver disease. Animals that drank the trehalose-spiked water had significantly lower levels of genetic markers for fatty liver disease, as well as lower amounts of triglycerides and cholesterol in their livers, compared with mice that didn’t consume trehalose.
Molecular Machines
What if we lived in a world run by molecular machines, too small to see but impacting all aspects of our everyday lives? In one sense, we already do: biology uses them for absolutely everything – from harvesting energy from the sun to the way that we see, with proteins being the most complicated of the lot. Scientists have taken to calling them machines because, just like those designed by humans, they produce mechanical motion in response to an input, allowing them to perform a task. Whereas biology has perfected its machines over billions of years of evolution, chemists keen to imitate these structures are just getting started.
In the late 1980s, researchers started building assemblies of molecules that contain mechanically interlocked components, where two or more parts can’t be separated without breaking a covalent bond. The most popular of these came to be the rotaxane – a dumbbell-shaped molecule with a ring wrapped around the centre, free to slide along the axle but too small to come off at either end. ‘The credit for making molecular machines attractive to chemists goes to Fraser Stoddart,’ recalls David Leigh of the University of Manchester, UK. ‘He had the vision to realise that these architectures gave you the possibility of large amplitude-controlled motions, and that that could be the basis of molecular machines.’
Just over a decade ago a team in the US led by Fraser Stoddart, now at Northwestern University in Illinois, showed that they could use rotaxanes to bend gold.1 They used redox chemistry to control the position of a macrocycle that shuttles back and forth along a thread between two stations: in the neutral state the macrocycle has a high affinity for a tetrathiafulvalene unit, but on oxidation it is repelled to sit much more comfortably on a naphthalene station. When two of these rotaxanes are coupled together, the rings find themselves either 4.2 or 1.4 nm apart depending on the redox state. By anchoring the macrocycles to a gold surface, the group were able to mimic the kind of contractions and extensions that you get in muscles and use these switches to bend micron-sized gold beams.
Reinventing the wheel
[...] The nanocar – a four-wheeled molecule that drives across a copper surface – made the news in 2011.2 Ben Feringa and co-workers at the University of Groningen in the Netherlands designed a motor that rotates in a single direction thanks to a series of conformational changes. Electronically exciting their molecule causes a photochemical isomerisation around a carbon–carbon double bond, and a helix inversion quickly follows. Two cycles of these geometric changes give a 360° rotation of the motor in a paddle-wheel type movement. Substitute four wheels for motors and when all of them are aligned to spin in the same direction, the molecule propels itself forward in a straight line.
‘The entire regime of motion in the molecular world is completely different to in the macroscopic world, and so what people call nanocars have nothing at all to do with the physics of a car,’ comments physicist Dean Astumian at the University of Maine, US. ‘It’s like when you look up in the night sky and see a constellation that looks like a bear: we wouldn’t think that the biology of a bear is useful for understanding how the stars in that constellation move relative to one another,’ he adds. Regardless of the questionable comparison, there’s no doubt that achieving this type of molecular directionality is no mean feat, especially given that molecules usually move around constantly and at random.
Ecology
'No One Died, No One's Health Was Damaged' - Fukushima's Big Lie
With the third anniversary of the Fukushima Daiichi nuclear catastrophe coming next week, the attempted Giant Lie about the disaster continues - a suppression of information, an effort at dishonesty of historical dimensions.
It involves international entities, especially the International Atomic Energy Agency, national governmental bodies - led in Japan by its current prime minister, the powerful nuclear industry and a global 'nuclear village' of scientists and others with a vested interest in atomic energy.
Deception was integral to the push for nuclear power from its start. Indeed, I opened my first book on nuclear technology, Cover Up: What You Are Not Supposed to Know About Nuclear Power, with:
"You have not been informed about nuclear power. You have not been told. And that has been done on purpose. Keeping the public in the dark was deemed necessary by the promoters of nuclear power if it was to succeed.
"Those in government, science and private industry who have been pushing nuclear power realized that if people were given the facts, if they knew the consequences of nuclear power, they would not stand for it."
A death toll of up to 600,000 is estimated in a study conducted for the Nordic Probabilistic Safety Assessment Group which is run by the nuclear utilities of Finland and Sweden.
Dr. Helen Caldicott, a founder of Physicians for Social Responsibility, told a symposium on 'The Medical Implications of Fukushima' held last year in Japan:
"The accident is enormous in its medical implications. It will induce an epidemic of cancer as people inhale the radioactive elements, eat radioactive vegetables, rice and meat, and drink radioactive milk and teas.
"As radiation from ocean contamination bio-accumulates up the food chain ... radioactive fish will be caught thousands of miles from Japanese shores. As they are consumed, they will continue the the cycle of contamination, proving that no matter where you are, all major nuclear accidents become local."
13C Pathway Analysis for the Role of Formate in Electricity Generation By Shewanella Oneidensis MR-1 Using Lactate In Microbial Fuel Cells
Abstract:
Microbial fuel cell (MFC) is a promising technology for direct electricity generation from organics by microorganisms. The type of electron donors fed into MFCs affects the electrical performance, and mechanistic understanding of such effects is important to optimize the MFC performance. In this study, we used a model organism in MFCs, Shewanella oneidensis MR-1, and 13C pathway analysis to investigate the role of formate in electricity generation and the related microbial metabolism. Our results indicated a synergistic effect of formate and lactate on electricity generation, and extra formate addition on the original lactate resulted in more electrical output than using formate or lactate as a sole electron donor. Based on the 13C tracer analysis, we discovered decoupled cell growth and electricity generation in S. oneidensis MR-1 during co-utilization of lactate and formate (i.e., while the lactate was mainly metabolized to support the cell growth, the formate was oxidized to release electrons for higher electricity generation). To our best knowledge, this is the first time that 13C tracer analysis was applied to study microbial metabolism in MFCs and it was demonstrated to be a valuable tool to understand the metabolic pathways affected by electron donors in the selected electrochemically-active microorganisms.
[Editor’s Note: The original article from which I found the above abstract stated, “...their findings speaks to a growing sustainability movement to capture energy from existing waste to potentially make treatment facilities more energy-efficient.”]
Physics
Soft Solids And The Science Of Cake
What do cake batter and a massive, offshore oil drilling rig have in common? The answer lies in a type of material known as a soft solid, which can behave either like a solid or like a liquid, depending upon the stress it is subjected to. Cake batter, molten chocolate, Marmite, custard and the foamed concrete used in oil wells are all examples of these 'dual personality' materials.
Soft solids are non-Newtonian fluids, which don't adhere to the same rules as 'normal' liquids. Newtonian fluids – such as water or cooking oil – don't change their behaviour as a result of how they have been handled, such as having been mixed or being left stagnant for days. For example, if a bowl of water is mixed for an hour at high speed, it will flow in exactly the same way at the end of the hour as at the beginning.
Non-Newtonian fluids – such as custard, cake batter or foamed concrete – are different. Sometimes they behave like a solid, and sometimes they behave like a liquid. For example, move quickly and firmly enough and it's possible to walk on custard. But stop moving, and you will start to sink. This is because custard gets thicker or thinner depending on the rate at which you try to move it. This is one way in which non-Newtonian fluids differ.
When trying to lighten either a cake or cement, one answer is simple: fill it with air bubbles. In cake batters, this leads to a fluffier cake. In oil wells, it makes for lightweight cement which is used to fill in the gaps between the pipe and the rock to prevent oil and gas from escaping.
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However, the ramifications of this research reach far beyond the world of cakes, due to the ubiquity of bubbly liquids and related soft solids. Although foamed concrete differs from honey – it starts off as viscoplastic rather than viscoelastic – the development of models that can accurately describe these soft solids will allow engineers to design and control them, and hopefully prevent them from going wrong.
MIT Develops Early Warning System For Rogue Waves
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Previous attempts at rogue wave detection have made use of complex systems that take a leave-no-wave-behind approach, tracking and simulating every single wave in a given body of water. This does provide a high-resolution picture of the sea state, but the method is extremely computationally intensive, making it too slow for quick detection.
The MIT method takes a similar idea, but simplifies things significantly. Rather than analyzing every single wave, the new tool looks for waves that are clustered together, rolling through the depths in a single movement. It's these groups of waves that tend to focus together, exchanging energy and eventually forming one huge, rogue wave.
The system uses an algorithm to determine the probability of these groups forming rogue waves based on their length and height, which as identified by analyzing wave data gathered by ocean buoys, combined with specialized wave water equations.
According to the team, the system is able to predict rogue waves 2-3 minutes before they fully develop, but in order for the tech to be utilized, platforms and ships will need to be fitted with compatible high-resolution scanning equipment, such as LIDAR and radar.