Mars will most likely develop rings similar to Saturn’s, when its largest moon, Phobos, gets close enough to break apart, according to a recently published study in Nature Geoscience. Mars would be the only inner planet with rings if this took place. Scientists predict it will happen in about 20 – 40 million years.
Unlike Earth’s moon, which is slowly moving away from us, Mars’s largest and inner most moon, Phobos, has been slowly moving towards its parent planet, and once close enough, will be torn into bits by Mars’s gravity. The aftermath of Phobos being torn apart may result in a large ring orbiting Mars, as well as bombarding Mars with meteors for years afterwards. The study concludes that it is far more likely that Phobos will break apart before making contact with Mars, creating rings around the red planet.
Phobos is the larger of Mars’s two moons, and is thought to be a “rubble planet” that is comprised of numerous rocks held together by gravity, to form a large clump with a crust only 100 meters thick, compared to Earth’s average 30 kilometer crust. Every 100 years Phobos orbits 2 metres closer to Mars, and is thought to break apart into thousands of small pieces over 20 million years from now, creating dense rings similar to Saturn’s.
Phobos is Mars’s largest moon, and is made up of thousands of boulders held together by gravity
All planets in our solar system have had rings at one point in time, including Earth, though most rings were too unstable to last very long, and either rained down as meteors, or flew out of orbit. Only the outer gas giant planets: Jupiter, Saturn, Uranus, and Neptune have retained their rings, which will make Mars the only inner planet to have rings again, and will probably be the last time any terrestrial planet gains new rings.
The researchers also said that several missions to Phobos have been proposed, and could help us learn more about asteroids, plate tectonics, and make measurements to test their theories.
Late in 2013, a novel variant of the Ebola virus emerged in Western Africa to start what would become the largest human epidemic on record. In a study published December 9th in Cell Host & Microbe, researchers used genome sequencing to trace the introduction and spread of the virus in Liberia–the second worst-affected country.
The findings suggest that the Ebola virus spread to Liberia multiple times from neighboring countries early during the outbreak, but the majority of Liberian cases are attributable to a single introduction of the virus, which rapidly spread throughout the country and subsequently refueled the ongoing outbreak in Guinea.
“Genome sequencing has played an important role in identifying and confirming chains of transmission throughout this outbreak, in the absence of good epidemiological data. However, relatively few sequences have been determined from patients in Liberia, even though this country had the highest number of Ebola-related deaths,” says senior study author Gustavo Palacios of the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID). “By providing a detailed view into the ongoing spread and diversification of the Ebola virus, this study supports ongoing surveillance and isolation efforts and provides critical information for developing effective control strategies.”
The Ebola virus is transmitted to people from its reservoir host and spreads in the human population through human-to-human transmission. Since it was first discovered in 1976, the virus has mainly affected remote villages in Africa, limiting the number of deaths associated with Ebola virus disease (EVD) despite the 50% average fatality rate. However, the latest outbreak reached major urban areas in Guinea, Liberia, Sierra Leone, and nearby countries, resulting in more than 28,000 reported cases and more than 11,000 deaths.
Dr. Gustavo Palacios
The World Health Organization declared that Ebola virus transmission in the human population had ended in Liberia on September 3rd and in Sierra Leone on November 7th of this year. Moreover, the last patient in Guinea, where the outbreak originated, tested negative for the Ebola virus twice as of November 22nd. “Despite encouraging signs of containment, the cluster of three confirmed cases of EVD that was recently reported in Liberia underscores the importance of robust surveillance measures to ensure the rapid detection of any reintroduction or re-emergence of the virus,” Palacios says.
Palacios and first author Jason Ladner of USAMRIID sequenced Ebola virus genomes from 139 EVD patients affected in the second, largest wave of the Liberian outbreak. They also analyzed 782 previously published sequences from throughout the Western African outbreak. Together, these samples span nearly one year of the epidemic, including the period during which 99% of the confirmed and probable cases were reported in Liberia.
While multiple early introductions of the Ebola virus from Guinea and/or Sierra Leone to Liberia were evident, the majority of Liberian cases were consistent with a single introduction in late May or early June 2014, around the start of the second wave of Liberian cases. Although infected individuals may have continued to enter Liberia from neighboring countries, surprisingly, these transmission chains did not substantially contribute to the Liberian portion of the outbreak.
Contact tracing has revealed at least three potential introductions of the Ebola virus to Liberia from Sierra Leone around the start of the second wave of Liberian cases. Analysis of the viral sequences suggests that one of these introductions, which has been linked to several EVD cases in Monrovia, including health care workers at Redemption Hospital, likely led to the largest wave of cases in Liberia.
Subsequently, the virus rapidly spread and diversified within Liberia. Moreover, reintroductions of the virus from Liberia served as an important source for the continuation of the ongoing Ebola outbreak in Guinea and its spread to Mali. “The widespread movement of the Ebola virus within Liberia, due to a high rate of migration in the country, is likely to have played an important role in the magnitude and longevity of the Liberian portion of the Ebola outbreak,” Ladner says. “Regular migration of infected individuals complicates surveillance and isolation efforts, which are critical for controlling Ebola outbreaks.”
Surprisingly, the study suggested that the Ebola virus did not appear to further adapt to humans during the outbreak, but additional research is needed to understand how the virus transitioned to humans at the beginning of the outbreak. Future efforts should also focus on exploring the public health implications of the findings. “A detailed investigation of Ebola virus control measures throughout Western Africa, in light of the movement patterns highlighted in our analysis, will be illustrative regarding the effectiveness of different management approaches,” Palacios says.
This work was supported by the Defense Threat Reduction Agency, Global Biosurveillance Technology Initiative, Global Emerging Infections System and the U.S. Agency for International Development. Additional support was received by the EU Seventh Framework Programme.
President Obama signed the U.S. Commercial Space Launch Competitiveness Act (H.R. 2262) into law Wednesday. This law recognizes the right of U.S. citizens to own asteroid resources they obtain and encourages the commercial exploration and utilization of resources from asteroids.
“This is the single greatest recognition of property rights in history,” commented Eric Anderson, co-founder and co-chairman of Planetary Resources, Inc. “This legislation establishes the same supportive framework that created the great economies of history, and will encourage the sustained development of space.”
The act provides for three things, mainly: facilitates exploration and commercial recovery of space resources by United States citizens; discourages governmental barriers to economic viability; and promotes the right of the U.S. to engage in commercial space exploration and recovery.
The act also recognizes the United States’ international obligations and that all activity will be subject to the authority of the federal government, which will supervise.
“A hundred years from now, humanity will look at this period in time as the point in which we were able to establish a permanent foothold in space,” stated Dr. Peter H. Diamandis, another co-founder and co-chairman of Planetary Resources. “In history, there has never been a more rapid rate progress than right now.”
The chief engineer of the organization also commented on the legislation: “This off-planet economy will forever change our lives for the better here on Earth. We celebrate this law as it creates a pro-growth environment for our emerging industry by encouraging private sector investment and ensuring an increasingly stable and predictable regulatory environment.”
Don’t have room for dessert? The bacteria in your gut may be telling you something. Twenty minutes after a meal, gut microbes produce proteins that can suppress food intake in animals, reports a study published November 24 in Cell Metabolism. The researchers also show how these proteins injected into mice and rats act on the brain reducing appetite, suggesting that gut bacteria may help control when and how much we eat.
The new evidence coexists with current models of appetite control, which involve hormones from the gut signalling to brain circuits when we’re hungry or done eating. The bacterial proteins–produced by mutualistic E. coli after they’ve been satiated–were found for the first time to influence the release of gut-brain signals (e.g., GLP-1 and PYY) as well as activate appetite-regulated neurons in the brain.
“There are so many studies now that look at microbiota composition in different pathological conditions but they do not explore the mechanisms behind these associations,” says senior study author Sergueï Fetissov of Rouen University and INSERM’s Nutrition, Gut & Brain Laboratory in France. “Our study shows that bacterial proteins from E. coli can be involved in the same molecular pathways that are used by the body to signal satiety, and now we need to know how an altered gut microbiome can affect this physiology.”
Mealtime brings an influx of nutrients to the bacteria in your gut. In response, they divide and replace any members lost in the development of stool. The study raises an interesting theory: since gut microbes depend on us for a place to live, it is to their advantage for populations to remain stable. It would make sense, then, if they had a way to communicate to the host when they’re not full, promoting host to ingest nutrients again.
In the laboratory, Fetissov and colleagues found that after 20 minutes of consuming nutrients and expanding numbers, E. coli bacteria from the gut produce different kinds of proteins than they did before their feeding. The 20 minute mark seemed to coincide with the amount of time it takes for a person to begin feeling full or tired after a meal. Excited over this discovery, the researcher began to profile the bacterial proteins pre- and post-feeding.
They saw that injection of small doses of the bacterial proteins produced after feeding reduced food intake in both hungry and free-fed rats and mice. Further analysis revealed that “full” bacterial proteins stimulated the release of peptide YY, a hormone associated with satiety, while “hungry” bacterial hormones did not. The opposite was true for glucagon-like peptide-1 (GLP-1), a hormone known to simulate insulin release.
The investigators next developed an assay that could detect the presence of one of the “full” bacterial proteins, called ClpB in animal blood. Although blood levels of the protein in mice and rats detected 20 minutes after meal consumption did not change, it correlated with ClpB DNA production in the gut, suggesting that it may link gut bacterial composition with the host control of appetite. The researchers also found that ClpB increased firing of neurons that reduce appetite. The role of other E.coli proteins in hunger and satiation, as well as how proteins from other species of bacteria may contribute, is still unknown.
“We now think bacteria physiologically participate in appetite regulation immediately after nutrient provision by multiplying and stimulating the release of satiety hormones from the gut,” Fetisov says. “In addition, we believe gut microbiota produce proteins that can be present in the blood longer term and modulate pathways in the brain.”
The International Space Station orbits the Earth at 28,000 km/h, fast enough to make it from our planet to the moon and back in a day.
The 1 million pound craft carries its six passengers around the circumference of the Earth every 90 minutes at that speed.
And now, thanks to Open Notify‘s API and coder Sten Hougaard, a senior front end developer who blogs at Netsi.dk, we can map it’s course in real time.
“I love to demonstrate how to use these features,” Hougaard told us about his use of Open Notify. The open source project was created by Nathan Bergey to provide “a simple programming interface for some of NASA’s awesomest data.”
“[Open Notify] is good sneak preview of what’s to come in the future web,” Hougaard told us. “I expect the APIs and a ‘data layer based’ web will be a big bright future for all of us, the users of the web.”
Here is the current position of ISS on a Google Map, travelling fast enough that you can actually watch the craft’s marker accumulate a trail. (Scroll up or down atop the map to zoom in or out.)
First-of-its-kind NASA mission will also demonstrate ability to deflect asteroids
NASA has detailed ARM: its mission to send a robotic spacecraft to an asteroid, pluck a boulder off of the surface, and put the rock into orbit around the moon. It will also use an Enhanced Gravity Tractor to redirect the course of the asteroid.
The Asteroid Redirect Mission (ARM) includes other important stages as well: after capture from the yet-undecided upon asteroid, astronauts will shuttle out to the robot in NASA’s Orion craft to study the surface and bring samples back.
Two technological goals were clearly stated by NASA in relation to ARM: The mission will demonstrate NASA’s ability to deflect an object in space that threatens the planet, and it will test capabilities that will be required for the first crewed mission to Mars.
The course of the mission is planned as follows: the robotic spacecraft would fly by the asteroid several times, optically scanning the surface. It would then land above the boulder targeted. It would attach arms to the surface of the boulder, then push off again from the asteroid. The robotic craft would analyze the boulder for three days.
The next stage would be demonstration of NASA’s ability to redirect an asteroid using what it calls an Enhanced Gravity Tractor (EGT): The robotic craft would measure, calibrate and use the gravitational attraction between the asteroid and itself to alter the course of the asteroid, sending it in a chosen direction.
Then the robotic craft will set off for the lunar orbit, making use of its time with the boulder by scanning it further. The rock will be sent into a stable orbit around the moon.
Astronauts will rocket out to the boulder in NASA’s Orion spacecraft, secure Orion to it, and the astronauts will take space walks to study and collect samples, leaving the rock in orbit around the moon when they return to Earth.
NASA plans to launch the ARM robotic spacecraft at the close of the decade.
The primary way that researchers know anything about the distribution of species in the natural world is via the specimen collections housed in museums all around the world. As a result, tremendous effort is being put into uploading data on those collections into free and accessible databases. But researchers reporting in the Cell Press journal Current Biology on November 16 have uncovered a big problem: mistaken identities in those collections are incredibly common, at least among tropical plants.
Since the 1970s, the world’s plant collections have more than doubled, but more than 50 percent of tropical specimens, on average, are likely to be incorrectly named, the study suggests.
“Part of the reason for such rampant misidentification is the huge increase in the number of specimens which have been collected in the last 50 years,” says Robert Scotland of the University of Oxford. “The other reason is the lack of expertise in many tropical plant groups. This produces a situation where huge numbers of incoming specimens can overwhelm any efforts to identify them by the few people with the necessary skill.”
This discovery has serious implications for the use of specimen data coming out of those natural history collections. That might sound discouraging, but it’s a problem that can be tackled.
“We estimate it takes £500 ($750) to revise a species, which means for the cost of one world-class footballer–[such as Barcelona megastar] Lionel Messi–it would be possible to monograph the entire flora of tropical plants,” Scotland says.
He and his colleagues say that they are now doing their part by actively exploring new integrated approaches to taxonomy. They’ve brought their techniques together into something they call “foundation monographs,” getting their start with two plant groups.
The findings come as yet another timely reminder of how much there is to learn about biodiversity. “We know so little about the natural world, but we still have a chance to document it properly!” Scotland says.
This report, “Widespread mistaken identity in tropical plant collections,” was funded by the Systematics Association and Linnean Society, the BBSRC & NERC., and was published in Current Biology.
A new network has been established by UK scientists to advance and promote research into cryobiology – the effects of extremely low temperature on living organisms and cells.
Cryopreservation is the process of placing cells, organs or even whole organisms at low temperatures so that they remain in a state of suspended animation and function is preserved.
Crucial area of research
At present, cryopreservation technology is only successful for cell lines and very small tissues. More research is required before whole organs can successfully be cryopreserved while retaining their biological integrity.
Dr de Magalhaes said: “Cryobiology is a crucial area of research for modern biotechnology due to the importance of biobanking; from developing reliable stem cell storage systems, organ banking for transplants as well as storage for engineered tissues.”
The network is made up of a group of UK researchers from Liverpool, Cambridge and Oxford who, together with international advisors, aim to advance research in cryopreservation and its applications, including the idea of cryopreserving whole humans, commonly known as cryonics.
Controversial topic
Cryonics has been a topic of much debate over the years, with many scientists doubting whether current cryogenically frozen individuals can ever be brought to life.
Dr de Magalhaes said: “Although cryonics is not feasible at present, technological breakthroughs in cryobiology may, in the future, decrease the amount of damage to levels that permit reversible cryopreservation.
“One of the goals of our research network is to discuss the ethical, medical, social and economic implications of these potential breakthroughs that would radically change our perceptions of life and death.”
NASA Satellite imagery of a barren and treeless steppe in northern Kazakhstan has revealed enormous earthworks that can only be seen from the air. Some of the formations date back 8000 years and are thought to have been built by the neolithic groups of the area.
Known as the Steppe Geoglyphs, these formations are as large as several football fields. The largest structure consists of 101 raised mounds, each 3 feet high and 30 feet across, creating a square with an X or cross intersecting it. There are at least 260 mounds, trenches, and ramparts in 5 different shapes found across the steppe.
The mounds were first discovered on Google Earth by a Kazakh economist and archaeology enthusiast Dimitry Dey in 2007. Since then, the Steppe Glyphs had gained little public attention until they were shown last year at an archaeology conference in Istanbul in which they were described as “unique” and “unstudied.”
The geoglyphs remained unstudied and virtually unknown until two weeks ago when NASA released high-definition satellite images, sparking public and archaeological interest. Archaeologists are trying to figure out what the importance of such massive arrays were to the neolithic people who created them, and why they can only be seen from above. Such a feat defies our current understanding of the capabilities of neolithic peoples to organize, build, and communicate.
“The idea that foragers could amass the numbers of people necessary to undertake large-scale projects — like creating the Kazakhstan geoglyphs — has caused archaeologists to deeply rethink the nature and timing of sophisticated large-scale human organization as one that predates settled and civilized societies,” Persis B. Clarkson, an archaeologist at the University of Winnipeg told the New York Times.
Archaeologists are hopeful that the Steppe Glyphs will provide further insight into just how the stone-age tribes functioned, and what kind of knowledge they had acquired. Many theories have been posed about the reason behind the glyphs, including aliens, relations to Hitler (even though the Swastika was used much earlier than the 20th century), and constellation mapping. Theories of the glyphs’ purpose range from the ridiculous to the entirely possible.
In March of 2007, Mr. Dey, 44, was at home watching “Pyramids, Mummies, and Tombs” on The Discovery Channel. “There are pyramids all over the Earth,” he remembered thinking. “In Kazakhstan there should be pyramids too.” Mr. Dey then searched through the landscape of Kazakhstan on Google Earth, and instead came across what he thought were old Soviet installations until finding more than 15 different formations.
Kazakhstan has also called for urgent protection by UNESCO as an important cultural heritage site — so far without reply. Earlier this year a formation called The Koga Cross was destroyed by road builders, even after Mr. Dey notified officials.
University of London study analyzes the upward spirals generated by positive experience, mood, and decision making, compared with the contrary downward ones
It’s long been known that mood biases our judgments and perceptions, but this effect has usually been regarded as irrational or disadvantageous. A new theory published Tuesday in Trends in Cognitive Sciences argues that mood draws on experiences and can, in fact, help us quickly adapt to changes in our environment. For example, experiencing unexpected gains on the stock market should improve a trader’s mood. That positive mood may then cause the trader to take more risks, essentially helping her adapt more quickly to a market that is generally on the rise.
According to the new theory, as people learn from experiences that are colored by their mood, their expectations come to reflect not only the reward associated with each particular state (such as each stock), but also recent changes in the overall availability of reward in their environment. In this way, the existence of mood allows learning to account for the impact of general environmental factors.
“This effect of mood should be useful whenever different sources of reward are interconnected or possess an underlying momentum,” says one of the study’s lead authors, Eran Eldar of University College London. “That may often be the case in the natural as well as in the modern world, as successes in acquiring skills, material resources, social status, and even mating partners may all affect one another.”
Eldar and his colleagues note that positive or negative moods maximize their usefulness by persisting only until expectations are fully in accordance with changes in rewards. (That may be why happiness eventually returns to a baseline level even following highly significant changes in circumstances, including winning the lottery.)
For instance, a negative mood that persists may cause a person to perceive many subsequent outcomes as worse than they really are, leading to a downward spiral. This might turn mood into a “self-fulfilling prophecy” and lead to the onset of a depressive episode. Therefore, by defining a potential function for mood and describing the learning processes that underlie it, the new theory may lead to a better understanding of the causes of mood disorders.
“We think that this novel approach may help reveal what predisposes particular individuals to bipolar disorder and depression,” Eldar says.
Because moods are ubiquitous and have significant impacts on our lives, it is likely that they have conferred a significant competitive advantage throughout the course of evolution. Being moody at times may be a small price to pay for the ability to adapt quickly when facing momentous environmental changes.
This work, “Mood as Representation of Momentum,” was completed by Eldar, Rutledge, Dolan, and Niv, was funded in part by the Wellcome Trust’s Cambridge UCL Mental Health and Neurosciences Network grant, the Max Planck Society, and an Army Research Office award, and was published in Cell’s Trends in Cognitive Sciences.
A Duke University team has created fibers that cause liquid to jump off their surface as it accumulates, leading to new possibilities in water purification, atmospheric moisture harvesting, and various drop collecting industrial material applications.
“Self-removal is essentially inevitable as long as the surface is reasonably hydrophobic,” said Chuan-Hua Chen of Duke University in Durham, North Carolina, a lead researcher of the study. High degrees of hydrophobia are not necessary to create self-removing droplets. Self-removal is based largely on a small surface area for liquid to bead upon.
Liquids jump off the fibers as they accumulated due to the composition and width of the fibers. So long as merged droplets are above a certain size, when they coalesce into almost-spheres to reduce surface area, some of the energy released turns into mechanical energy sufficient to detach the bead and propel it away from the surface.
The speed at which a droplet launches from a surface is based on the degree to which the ratio radius of the droplet trying to reduce contact with the surface exceeds the critical value of attachment to the surface.
It is the first time self-removing droplets have been demonstrated on curved surface such as fibers, and the team believes the technology should be applicable to emulsions so long as the emulsion is not too vicious.
