An arms race among venomous animals?

This is an Anderson's Pitviper (Trimeresurus Andersoni), a highly venomous snake, photographed by Dr. Kartik Sunagar in the Andaman Islands of India.

In a new study published in the journalPLOS Genetics, scientists at the Hebrew University of Jerusalem have revealed new discoveries about how animal venom evolves.

Venom is a complex mixture of proteins and other toxic chemicals produced by animals such as snakes and spiders, either to incapacitate their prey or to defend against predators. The influence of positive selection (the process by which a protein changes rapidly over evolutionary time scales) in expanding and diversifying animal venoms is widely recognized.

This process was hypothesized to result from an evolutionary chemical arms race, in which the invention of potent venom in the predatory animals and the evolution of venom resistance in their prey animals, exert reciprocal selection pressures.

In contrast to positive selection, the role of purifying selection (also known as negative selection, which is the selective removal of deleterious genetic changes from a population) has rarely been considered in venom evolution.

Moreover, venom research has mostly neglected ancient animal groups in favor of focusing on venomous snakes and cone snails, which are both "young" animal groups that originated only recently in evolutionary timescales, approximately 50 million years ago. Consequently, it was concluded that venom evolution is mostly driven by positive selection.

In the new study, Dr. Yehu Moran at the Hebrew University's Department of Ecology, Evolution and Behavior and the guest scientist Dr. Kartik Sunagar examined numerous venom genes in different animals in order to unravel the unique evolutionary strategies of toxin gene families.

The researchers analyzed and compared the evolutionary patterns of over 3500 toxin sequences from 85 gene families. These toxins spanned the breadth of the animal kingdom, including ancient venomous groups such as centipedes, scorpions, spiders, coleoids (octopus, cuttlefish and squids) and cnidarians (jellyfish, sea anemones and hydras).

Unexpectedly, despite their long evolutionary histories, ancient animal groups were found to have only accumulated low variation in their toxins.

The analysis also revealed a striking contrast between the evolution of venom in ancient animal groups as compared to evolutionarily "young" animals. It also highlighted the significant role played by purifying selection in shaping the composition of venoms.

According to Dr. Yehu Moran, "Our research shows that while the venoms of ancient lineages evolve more slowly through purifying selection, the venoms in more recent lineages diversify rapidly under the influence of positive selection."

The findings enable the postulation of a new theory of venom evolution. According to this theory, toxin-producing genes in young venomous groups that enter a novel ecological niche, experience a strong influence of positive selection that diversifies their toxins, thus increasing their chances to efficiently paralyze relevant prey and predatory species in the new environment.

However, in the case of the ancient venomous groups, where the venom is already "optimized" and highly suitable for the ecological niche, the venom's rate of accumulating variations slows down under the influence of purifying selection, which preserves the potent toxins generated previously.

The proposed "two-speed" mode of venom evolution highlights the fascinating evolutionary dynamics of this complex biochemical cocktail, by showing for the first time the significant roles played by different forces of natural selection in shaping animal venoms.

According to Drs. Moran and Sunagar, "The 'two-speed' mode of evolution of animal venoms involves an initial period of expansion, resulting in the rapid diversification of the venom arsenal, followed by longer periods of purifying selection that preserve the now potent toxin pharmacopeia. However, species that have entered the stage of purification and fixation may re-enter the period of expansion if they experience a major shift in ecology and/or environment."

Source : Journal PLOS Genetics (http://dx.doi.org/10.1371/journal.pgen.1005596)

The largest to have existed - giant rat fossils

Archaeologists with The Australian National University (ANU) have discovered fossils of seven giant rat species on East Timor, with the largest up to 10 times the size of modern rats.

Dr Julien Louys of the ANU School of Culture, History and Language, who is helping lead the project said these are the largest known rats to have ever existed.

"They are what you would call mega-fauna. The biggest one is about five kilos, the size of a small dog," Dr Louys said.

"Just to put that in perspective, a large modern rat would be about half a kilo."

The work is part of the From Sunda to Sahul project which is looking at the earliest human movement through Southeast Asia. Researchers are now trying to work out exactly what caused the rats to die out.

Dr Louys said the earliest records of humans on East Timor date to around 46,000 years ago, and they lived with the rats for thousands of years.

"We know they're eating the giant rats because we have found bones with cut and burn marks," he said.

"The funny thing is that they are co-existing up until about a thousand years ago. The reason we think they became extinct is because that was when metal tools started to be introduced in Timor, people could start to clear forests at a much larger scale."

Dr Louys said the project team is hoping to get an idea of when humans first moved through the islands of Southeast Asia, how they were doing it and what impact they had on the ecosystems. The information can then be used to inform modern conservation efforts.

"We're trying to find the earliest human records as well as what was there before humans arrived," Dr Louys said.

"Once we know what was there before humans got there, we see what type of impact they had."

Dr Louys returned from the project's latest expedition to East Timor in August and has presented the findings at the Meetings of the Society of Vertebrate Palaeontology in Texas.

Source : Australian National University

A new dimension to high-temperature superconductivity discovered

A team led by scientists at the Department of Energy's SLAC National Accelerator Laboratory combined powerful magnetic pulses with some of the brightest X-rays on the planet to discover a surprising 3-D arrangement of a material's electrons that appears closely linked to a mysterious phenomenon known as high-temperature superconductivity.

This unexpected twist marks an important milestone in the 30-year journey to better understand how materials known as high-temperature superconductors conduct electricity with no resistance at temperatures hundreds of degrees Fahrenheit above those of conventional metal superconductors but still hundreds of degrees below freezing. The study was published today in Science.
The study also resolves an apparent mismatch in data from previous experiments and charts a new course for fully mapping the behaviors of electrons in these exotic materials under different conditions. Researchers have an ultimate goal to aid the design and development of new superconductors that work at warmer temperatures.

'Totally Unexpected' Physics

"This was totally unexpected, and also very exciting. This experiment has identified a new ingredient to consider in this field of study. Nobody had seen this 3-D picture before," said Jun-Sik Lee, a SLAC staff scientist and one of the leaders of the experiment conducted at SLAC's Linac Coherent Light Source (LCLS) X-ray laser. "This is an important step in understanding the physics of high-temperature superconductors."
The dream is to push the operating temperature for superconductors to room temperature, he added, which could lead to advances in computing, electronics and power grid technologies.
There are already many uses for standard superconducting technology, from MRI machines that diagnose brain tumors to a prototype levitating train, the CERN particle collider that enabled the Nobel Prize-winning discovery of the Higgs boson and ultrasensitive detectors used to hunt for dark matter, the invisible constituent believed to make up most of the mass of the universe. A planned upgrade to the LCLS, known as LCLS-II, will include a superconducting particle accelerator.

The New Wave in Superconductivity

 he 3-D effect that scientists observed in the LCLS experiment, which occurs in a superconducting material known as YBCO (yttrium barium copper oxide), is a newly discovered type of 'charge density wave.' This wave does not have the oscillating motion of a light wave or a sound wave; it describes a static, ordered arrangement of clumps of electrons in a superconducting material. Its coexistence with superconductivity is perplexing to researchers because it seems to conflict with the freely moving electron pairs that define superconductivity.

The 2-D version of this wave was first seen in 2012 and has been studied extensively. The LCLS experiment revealed a separate 3-D version that appears stronger than the 2-D form and closely tied to both the 2-D behavior and the material's superconductivity.

The experiment was several years in the making and required international expertise to prepare the specialized samples and construct a powerful customized magnet that produced magnetic pulses compressed to thousandths of a second. Each pulse was 10-20 times stronger than those from the magnets in a typical medical MRI machine.

A Powerful Blend of Magnetism and Light

Those short but intense magnetic pulses suppressed the superconductivity of the YBCO samples and provided a clearer view of the charge density wave effects. They were immediately followed at precisely timed intervals by ultrabright LCLS X-ray laser pulses, which allowed scientists to measure the wave effects.
"This experiment is a completely new way of using LCLS that opens up the door for a whole new class of future experiments," said Mike Dunne, LCLS director.

Researchers conducted many preparatory experiments at SLAC's Stanford Synchrotron Radiation Lightsource (SSRL), which also produces X-rays for research. LCLS and SSRL are DOE Office of Science User Facilities. Scientists from SIMES, the Stanford Institute for Materials and Energy Sciences at SLAC, and SSRL and LCLS were a part of the study.

 Researchers discover a new dimension to high-temperature superconductivity
A view of the X-ray Correlation Spectroscopy experimental station at SLAC's Linac Coherent Light Source (LCLS) X-ray laser.

"I've been excited about this experiment for a long time," said Steven Kivelson, a Stanford University physics professor who contributed to the study and has researched high-temperature superconductors since 1987. Kivelson said the experiment sets very clear boundaries on the temperature and strength of the magnetic field at which the newly observed 3-D effect emerges. "There is nothing vague about this," he said. "You can now make a definitive statement: In this material a new phase exists." The experiment also adds weight to the growing evidence that charge density waves and superconductivity "can be thought of as two sides of the same coin," he added.

In Search of Common Links

But it is also clear that YBCO is incredibly complex, and a more complete map of all of its properties is required to reach any conclusions about what matters most to its superconductivity, said Simon Gerber of SIMES and Hoyoung Jang of SSRL, the lead authors of the study.

Follow-up experiments are needed to provide a detailed visualization of the 3-D effect, and to learn whether the effect is universal across all types of high-temperature superconductors, said SLAC staff scientist and SIMES investigator Wei-Sheng Lee, who co-led the study with Jun-Sik Lee of SSRL and Diling Zhu of LCLS. "The properties of this material are much richer than we thought," Lee said.
"We continue to make new and surprising observations as we develop new experimental tools," Zhu added.

Martian desiccation

Mars has been all over the news, from the blockbuster finding of seasonal water on the Red Planet to the wildly successful film, The Martian. Now, researchers--including those at the University of Iowa--have learned more about what happened to the climate on Mars since it was a warm and watery planet billions of years ago.

The researchers announced on Thursday that NASA's MAVEN (Mars Atmosphere and Volatile Evolution) mission has determined the rate at which the Martian atmosphere currently is losing gas to space via stripping by the solar wind. Loss of gas to space appears to have been an important part of why the Martian climate went from an early, warm, wet one that might have been able to support life at the surface to the cold, dry, desert planet we see today.

Jasper Halekas, associate professor in physics and astronomy at the UI and principal investigator of the Solar Wind Ion Analyzer instrument on MAVEN, took part in a NASA media briefing in which the agency gave its first results from the mission.

Halekas explains the sun has played a role in the planet's loss of atmosphere and water to space, by the solar wind accelerating ions (electrically charged gas atoms) in the Martian upper atmosphere and stripping them from the planet altogether. He says that powerful solar storms, called coronal mass ejections, can multiply the ions' escape by as much as a factor of 20.

Halekas adds that the coronal mass ejections produce such a pronounced effect because the solar storms collapsed the Martian magnetosphere, reducing its size by approximately 600 miles, and exposing more of the planet's atmosphere to the solar wind.

"The removal of atmosphere from Mars by episodic extreme events may have been very important over Mars' history, just as a single tsunami can remove a portion of the ocean shore that would have taken millennia to erode by the steady lapping of the tides," Halekas says.

The first scientific results from the MAVEN mission were published online on Thursday in a series of papers in the journals Science and Geophysical Research Letters. Halekas and Suranga Ruhunusiri, a post-doctoral researcher in physics and astronomy at the UI, are co-authors on 21 of the papers and are lead authors on three manuscripts.

MAVEN measurements have demonstrated that the solar wind is able to strip away gas at a rate of about 100 grams (equivalent to roughly 1/4 pound) every second. The loss comes from three different regions around the planet: above the Martian poles in a "polar plume"; down the "tail," where the solar wind flows behind Mars; and from the extended cloud of gas that always surrounds Mars.

A series of dramatic solar storms hit Mars' atmosphere in March 2015, and MAVEN found that the loss was accelerated. The combination of greater loss rates and increased solar storms in the past suggests that loss of atmosphere to space was likely a major process in changing the Martian climate.

"Like the theft of a few coins from a cash register every day, the loss becomes significant over time," says MAVEN Principal Investigator Bruce Jakosky, of the University of Colorado. "More importantly, with MAVEN we've seen that the atmospheric erosion increases significantly during solar storms. So we think that the loss rate was much higher billions of years ago when the sun was young and more active. As a result, we expect that loss of atmosphere to space was likely to have been a major process in changing the Martian climate."

The mission's goal is to determine how much of the planet's atmosphere and water has been lost to space. Scientists are interested in the history of liquid water on Mars because it has had a major geological impact on the surface over time and because it is necessary for life as we know it to exist at the surface.

MAVEN has been operating at Mars for just over a year and is about to complete its primary science mission on November 16, 2015.

Antimatter not so different after all

Due to the diligence of a Rice University student and his calculations, humanity now knows a little more about the universe.

Kefeng Xin, a graduate student at Rice, is one of a handful of primary authors who revealed evidence this week that the attractive force between antiprotons is similar to that between protons -- and measured it.

Specifically, the team measured two important parameters: the scattering length and the effective range of interaction between two antiprotons. This gave scientists a fundamental new way to understand the force that holds together the nuclei in antimatter and how this compares to matter.

"This is about the subtle difference in the way matter and antimatter interact with each other," said Rice physicist Frank Geurts.

Antiprotons carry the opposite electrical charge and spin that protons do. Like all matter and antimatter, both were created at the instant of the Big Bang. Physicists are still trying to understand why they see so few antiparticles in nature even though particles and antiparticles were produced in equal amounts and annihilate each other on contact.

"It could have been that antimatter didn't have the same attractive force as matter and would have helped explain how these differences, during the initial part of the Big Bang, might have resulted in antimatter not having survived in the shape of stars and planets, as matter did," Geurts said.

"That's where this research is helpful. The interactions between two antimatter particles turn out to be quite similar to matter particles. It may not give us a solution to the bigger problem, but we most definitely removed one option," he said.

The find was reported in Nature on behalf of the more than 500 scientists, including Geurts, who work on the STAR experiment, part of the Relativistic Heavy Ion Collider (RHIC) at the U.S. Department of Energy's Brookhaven National Laboratory. Brookhaven's story on the discovery appears here.

The scattering length is a measurement of how particles deviate as they travel from source to destination; their paths are visible as three-dimensional traces captured by STAR (which is short for Solenoid Tracker at RHIC). The effective range indicates how close particles need to be for their charges to influence each other, like magnets.

Both are measured in femtometers. One femtometer is one-millionth of a nanometer; a nanometer is one-billionth of a meter.

For antiprotons measured at RHIC, the scattering length was roughly 7.41 femtometers, and the effective range was 2.14 femtometers, nearly equivalent to their proton counterparts. Measuring distances that small involves both sophisticated equipment and sophisticated calculations.

"This discovery isn't a surprise," said Xin, whose Ph.D. thesis focuses on rather exotic systems called muonic atoms. "We've been studying the interaction between nucleons (particles that make up an atom's nucleus) for decades, and we've always thought the forces between antimatter particles are the same as for matter. But this is the first time we've been able to quantify it."

Xin, a student of Geurts, applied methods developed in his thesis to the analysis. The first task was to determine which particles produced in a collision were indeed antiprotons and whether any two were in close enough proximity to influence each other. Then came correlating their momentum from creation to destruction, typically a few nanoseconds.

"All of the data we collected in 2011 is from 500 million events (collisions between two heavy gold ions)," Xin said. "Pretty much every event can contribute."

Antimatter can be created in small amounts with a collider like RHIC and analyzed. The collider accelerates the nuclei of heavy atoms to nearly the speed of light and smashes them together to produce elemental particles, antiparticles and exotic materials like quarks, muons and plasmas. All of these can be characterized by tools built at Rice and elsewhere as part of STAR.

RHIC smashed gold ions to produce hundreds of millions of particles, which can be detected by the ionization traces they leave in a gas-filled cylinder that surrounds the collision and a "time-of-flight" sensor. The instrument, the construction of which was led by Rice, tells researchers how many nanoseconds it takes particles to travel from the point of impact to sensors at the outer boundaries of the collider.

"RHIC is ideal for this kind of experiment because it allows us to dump a boatload of energy into a very small volume and have many particles come out of it," Geurts said. "The multiplicity is important. If you don't make a lot of particles, the odds of having them interact with each other is slim."

Researchers from 52 institutions that are part of the STAR collaboration are co-authors of the Nature paper. Rice co-authors include graduate students Daniel Brandenburg, Joey Butterworth and Nick Luttrell; research scientist Geary Eppley; and Pablo Yepes, a senior faculty fellow in physics and astronomy. Geurts is an associate professor of physics and astronomy.

Source : Journal Nature

Diamonds may not be so rare as once thought

"Diamond formation in the deep Earth, the very deep Earth, may be a more common process than we thought," said Johns Hopkins geochemist Dimitri A. Sverjensky, whose article co-written with doctoral student Fang Huang appears today in the online journalNature Communications. The report says the results 'constitute a new quantitative theory of diamond formation,' but that does not mean it will be easier to find gem-qualitydiamonds and bring them to market.

For one thing, the prevalence of diamonds near the Earth's surface—where they can be mined—still depends on relatively rare volcanic magma eruptions that raise them from the depths where they form. For another, the diamonds being considered in these studies are not necessarily the stuff of engagement rings, unless the recipient is equipped with a microscope. Most are only a few microns across and are not visible to the unaided eye.

Using a chemical model, Sverjensky and Huang found that these precious stones could be born in a natural chemical reaction that is simpler than the two main processes that up to now have been understood to produce diamonds. Specifically, their model—yet to be tested with actual materials—shows that diamonds can form with an increase in acidity during interaction between water and rock.

The common understanding up to now has been that diamonds are formed in the movement of fluid by the oxidation of methane or the chemical reduction of carbon dioxide. Oxidation results in a higher oxidation state, or a gain of electrons. Reduction means a lower oxidation state, and collectively the two are known as 'redox' reactions.

"It was always hard to explain why the redox reactions took place," said Sverjensky, a professor in the Morton K. Blaustein Department of Earth and Planetary Sciences in the university's Krieger School of Arts and Sciences. The reactions require different types of fluids to be moving through the rocks encountering environments with different oxidation states.

The new research showed that water could produce diamonds as its pH falls naturally - that is, as it becomes more acidic—while moving from one type of rock to another, Sverjensky said.

The finding is one of many in about the last 25 years that expands scientists' understanding of how pervasive diamonds may be, Sverjensky said.

"The more people look, the more they're finding diamonds in different rock types now," Sverjensky said. "I think everybody would agree there's more and more environments of diamond formation being discovered."

Nobody has yet put a number on the greater abundance of diamonds, but Sverjensky said scientists are working on that with chemical models. It's impossible to physically explore the great depths at which diamonds are created: roughly 90 to 120 miles below the Earth's surface at intense pressure and at temperatures about 1,650 to 2,000 degrees Fahrenheit.

The deepest drilling exploration ever made was about 8 or 9 miles below the surface, he said.

If the study doesn't shake the diamond markets, it promises to help shed light on fluid movement in the deep Earth, which helps account for the carbon cycle on which all life on the planet depends.

"Fluids are the key link between the shallow and the deep Earth," Sverjensky said. "That's why it's important."

Distant world's weather is mixed bag of hot dust and molten rain

Weather patterns in a mysterious world beyond our solar system have been revealed for the first time, a study suggests.

Layers of clouds, made up of hot dust and droplets of molten iron, have been detected on a planet-like object found 75 light years from Earth, researchers say.

Findings from the study could improve scientists' ability to find out if conditions in far-off planets are capable of sustaining life, the team of astronomers suggests.

A team led by the University of Edinburgh used a telescope in Chile to study the weather systems in the distant world - known as PSO J318.5-22 - which is estimated to be around 20 million-years-old.

Researchers captured hundreds of infra-red images of the object as it rotated over a 5-hour period. By comparing the brightness of PSO J318.5-22 with neighbouring bodies, the team discovered that it is covered in multiple layers of thick and thin cloud. These cause changes to the brightness of the distant world as it rotates, the team says.

The far-off world is around the same size as Jupiter - the largest planet in our solar system - but is roughly eight times more massive, the team says. Temperatures inside clouds on PSO J318.5-22 exceed 800°C, researchers say.

The team were able to accurately measure changes in brightness on PSO J318.5-22 because it does not orbit a star. Stars like our sun emit huge amounts of light, which can complicate measurements made of the brightness of objects orbiting them, researchers say.

The team hopes to adapt the technique so they can study planets that do orbit stars. Such techniques may eventually be applicable to cooler, lower mass planets, which are more likely to be capable of supporting life, researchers say.

The study, published in The Astrophysical Journal, was funded by the Science and Technology Facilities Council. The work was carried out in collaboration with researchers based in the US, Germany, France and Spain.

Dr Beth Biller, of the University of Edinburgh's School of Physics and Astronomy, who led the study, said: "This discovery shows just how ubiquitous clouds are in planets and planet-like objects. We're working on extending this technique to giant planets around young stars, and eventually we hope to detect weather in Earth-like exoplanets that may harbour life."

Vast energy value in human waste

Biogas from human waste, safely obtained under controlled circumstances using innovative technologies, is a potential fuel source great enough in theory to generate electricity for up to 138 million households - the number of households in Indonesia, Brazil, and Ethiopia combined.

A report today from UN University's Canadian-based Institute for Water, Environment and Health estimates that biogas potentially available from human waste worldwide would have a value of up to US$ 9.5 billion in natural gas equivalent.

And the residue, dried and charred, could produce 2 million tonnes of charcoal-equivalent fuel, curbing the destruction of trees.

Finally, experts say, the large energy value would prove small relative to that of the global health and environmental benefits that would accrue from the safe treatment of human waste in low-resource settings.

"Rather than treating our waste as a major liability, with proper controls in place we can use it in several circumstances to build innovative and sustained financing for development while protecting health and improving our environment in the process," according to the report, "Valuing Human Waste as an Energy Resource."

The report uses average waste volume statistics, high and low assumptions for the percentage of concentrated combustable solids contained (25 - 45%), its conversion into biogas and charcoal-like fuel and their thermal equivalents (natural gas and charcoal), to calculate the potential energy value of human waste.

Biogas, approximately 60% methane by volume, is generated through the bacterial breakdown of faecal matter, and any other organic matter, in an oxygen free (anaerobic) system.

Dried and charred faecal sludge, meanwhile, has energy content similar to coal and charcoal.

UN figures show that 2.4 billion people lack access to improved sanitation facilities and almost 1 billion people (about 60% of them in India) don't use toilets at all, defecating instead in the open.

If the waste of only those practicing open defecation was targeted, the financial value of biogas potentially generated exceeds US$ 200 million per year and could reach as high as $376 million. The energy value would equal that of the fuel needed to generate electricity for 10 million to 18 million local households. Processing the residual faecal sludge, meanwhile, would yield the equivalent of 4.8 million to 8.5 million tonnes of charcoal to help power industrial furnaces, for example.

World already reuses the water and nutrients in wastewater

Says lead author Corinne Schuster-Wallace: "Increasingly, water-scarce regions are being driven to separate and reuse the water in wastewater, particularly to expand marginal agricultural lands. There is a technological opportunity, particularly in rural growth areas and small towns, to derive energy as well from this resource."

UNU-INWEH Senior Research Fellow Chris Metcalfe of Trent University notes that human waste, as with animal waste, is already used to improve food production in many places around the world, governed by guidelines to ensure its safe use.

A study in Sweden established that human urine contains over 300 g of phosphorous, 900 g of potassium and 300 g of sulphur per cubic meter. According to the World Health Organization, an individual's body excretes an estimated 4.5 kg of nitrogen and 548 g of phosphorus per year.

"We recycle the nutrients in human waste effectively via agriculture in many places, yet the potential energy value of human waste has been given much less attention to date," says Dr. Metcalfe, a report co-author along with UNU consultant Chris Wild. "Challenges are many but clearly there is a compelling, multi-dimensional financial case to be made for deriving energy from waste."

Says UNU-INWEH Director Zafar Adeel: "When it comes to creating misery and poverty, human waste mismanagement has few rivals. If we can demonstrate a simple, cost effective new approach in low-resource settings, if we can successfully make a business case and change the economic paradigm of human waste management, we can advance development, protect the environment and help reduce sanitation problems causing one-tenth of all world illnesses."

"World Toilet Day, upcoming November 19, offers the opportunity to promote new thinking and to continue puncturing the taboos in many places that inhibit discussion and perpetuate the disgrace and tragedy of inadequate human waste management in many developing world areas. This report contributes to that goal."

Waste to wealth

With initial seed funds from federally-funded Grand Challenges Canada, UNU-INWEH in partnership with the Ugandan Ministry of Water and Environment, its agencies, and other NGO and academic institutions, established the Waste to Wealth national framework.

Waste to Wealth utilises modern anaerobic digestion technologies linked to sanitation systems.

With a focus on rural growth centers and small towns, as well as high population density institutions such as schools and prisons, the biogas and residual material left from energy conversion is a valuable economic resource to provide a return on investment in bioenergy technologies.

The ultimate goal of Waste to Wealth is decentralised (on site) faecal waste management and to help bridge the finance gap for sanitation in Uganda. By identifying value in waste (energy and /or fertilizer), Waste to Wealth provides an incentive to use toilets and a mechanism to finance both upfront capital costs as well as facility operation, maintenance, and expansion. In addition to the economic opportunities, sanitation interventions have known benefits to individual, household and community health and wellbeing.

Video: http://bit.ly/1GH9oRy

Photos: http://bit.ly/1RcC1qr

Website: http://inweh.unu.edu/waste-to-wealth

Phase two of the project involves proof of concept of a series of proposed initiatives, including equipping a Ugandan prison with a $100,000 system requiring approximately $5,000 in annual operating costs, expected to pay for itself through fuel cost savings within 2 years.

Waste to Wealth is one of several pilot projects in Africa to have received seed grants from Grand Challenges Canada for the systematic collection of waste for processing into a variety of energy or agricultural products.

Related projects in Africa include:

Kenya

• Collecting and converting human waste into solid fuel for use by cement plants and other industries
• Franchising toilets; profitably, safely collecting and removing the waste daily, converting it into fuel and fertilizer, and
• Collecting human waste and converting it into high quality, emission free bio-charcoal cooking fuel

Uganda

Production of biogas and organic fertilizer from street waste

NASA sees Cyclone Chapala approaching landfall in Yemen

NASA's Aqua satellite and the GPM satellite passed over Cyclone Chapala as it was approaching landfall in central Yemen on November 2. The Global Precipitation Measurement Mission or GPM core satellite analyzed the heavy rain falling in the major hurricane.

On Nov. 2, 2015 at 09:40 UTC (4:40 p.m. EDT) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA's Aqua satellite captured an image of Tropical Cyclone Chapala as the eye of the storm was approaching the Yemen coast. Chapala maintained an eye, although it appeared cloud-covered. Animated multispectral satellite imagery shows the system has maintained a 15-nautical-mile-wide eye and structure. The image was created by the MODIS Rapid Response Team at NASA's Goddard Space Flight Center, Greenbelt, Maryland.

Chapala weakened from category four intensity a couple days ago while maintaining a course that steers it toward Yemen.

On Nov. 2 at 0311 UTC (Nov. 1 at 10:11 p.m. EST) the GPM core satellite saw the heaviest rainfall on the western and southern quadrants of the storm, falling at more than 50 mm (1.90 inches) per hour. The most intense rainfall was occurring just southwest of the eye, where rain was falling up to 65 mm (2.5 inches) per hour. GPM is a satellite that is jointly managed by NASA and the Japan Aerospace Exploration Agency.

A couple of days before, the GPM core observatory satellite had another good look at tropical cyclone Chapala. On October 31, 2015 at 0331 UTC (Oct. 30 at 11:31 p.m. EDT) Chapala was a very powerful tropical cyclone with maximum sustained winds of about 117 knots (135 mph). GPM's Microwave Imager (GMI) instrument measured rain dropping at a rate of over 88 mm (3.5 inches) per hour northwest of Chapala's eye.

GPM's Dual-Frequency Precipitation Radar (DPR) swath of coverage passed to the east of Chapala's eye. Feeder bands on that side of the tropical cyclone were found by DPR to be dropping rain at a rate of about 44 mm (1.7 inches) per hour. A 3-D view was created at NASA Goddard looking toward the east. It was derived from GPM's Ka and Ku band radar data. It shows that storm tops on Chapala's eastern side were reaching heights of over 13.4 km (8.3 miles).

At 1500 UTC (10 a.m. EST), Tropical Cyclone Chapala's maximum sustained winds were still near 105 knots (120.4 mph/194.5 kph). That makes Chapala a major hurricane, Category three on the Saffir-Simpson Wind Scale. Chapala was centered near 13.5 degrees north latitude and 50.3 degrees east longitude, about 110 nautical miles east-southeast of Mukalla, Yemen. Chapala has moved to the west at 10 knots (11.5 mph/18.5 kph).

The Joint Typhoon Warning Center (JTWC) expects landfall to occur early on November 3, southwest of Mukalla. JTWC forecasters noted that dry air that is emanating from the Arabian Peninsula will continue to weaken the storm in addition to increasing vertical wind shear. The cyclone is expected to decay rapidly after landfall and dissipate by November 4.

New study suggests fair division of chores leads to better sex life

Looking for more and better sex? If you're a man, you might consider doing the dishes once in a while.

A new study out of the University of Alberta reveals that couples enjoyed more frequent and satisfying sex for both partners when men made a fair contribution to housework. The same study also found there's no relationship between the amount of housework male partners completed and the sexual functioning of a couple.

The new study contradicts a widely reported 2012 US study entitled Egalitarianism, Housework, and Sexual Frequency in Marriage (Kornrich et al. 2012) that stated that when men perform what is regarded traditionally as female housework, things like doing the dishes, cooking and laundry, the couple had less sex.

"(That study) didn't ring true," said Dr. Matt Johnson, a family ecology professor in the Department of Human Ecology at the University of Alberta. "It didn't fit with my intuition and background experiences as a couple's therapist."

Johnson pored over data from a five-year study of 1,338 German couples to see if the amount of housework the male partner did was a predictor of a couple's sex life. He didn't find any connection. He also looked men's perception of whether they made a fair contribution to housework, and how that was related to their sex life.

"In any relationship, the amount of housework is going to mean something different based on the couple's context, based on their own expectations for what each partner should be doing, and their comparison levels of what happens with other couples they know," Johnson explained.

He found that when men perceived their contributions to the division of labour as fair, the couple engaged in more frequent sex and both male and female partners were more satisfied with their sex life.

Johnson acknowledged there are cultural differences between Germany and the US and explained that Germany tends to have more traditional gender roles than the US. And men, on average, tend to do less housework there, based on some studies, than in North America.

"There are cultural differences but if the logic held from the prior studies, we would have expected to have a more pronounced negative impact of housework on sexuality in Germany because it's a bit more traditional. But that wasn't the case at all," said Johnson.

He added that the findings are important for couples seeking to maintain sexual intimacy while balancing the demands of daily life.

"Rather than avoiding chores in the hopes of having more sex, as prior research would imply, men are likely to experience more frequent and satisfying passion for both partners between the sheets when they simply do their fair share."

Source : Skip the Dishes? Not so Fast! Sex and Housework Revisited, has been published in online first format and will appear in print in a future issue of the Journal of Family Psychology. Link to: http://psycnet.apa.org/psycinfo/2015-46448-001/

Uncovering the secrets of ice that burns

Methane hydrates are a kind of ice that contains methane, and that form at certain depths under the sea or buried in permafrost. They can also form in pipelines that transport oil and gas, leading to clogging. Yet methane hydrates are nearly impossible to study because it is very hard to get samples, and the samples themselves are highly unstable in the laboratory.

A team of scientists from Norway, China and the Netherlands has now shown how the size of grains of the molecules that make up the natural structure of methane hydrates determines how they behave if they are loaded with weight or disturbed.

That could have important implications for everything from climate science to their use as a future energy source, said Zhiliang Zhang, a professor at the Norwegian University of Science and Technology and founder of the university's Nanomechanical Lab.

"If we have basic knowledge about the mechanical properties of methane hydrates, we can use this information so that we manage them properly," Zhang said. "How methane hydrates behave can have a big impact on safety, environmental issues and climate change."

Poorly understood and unstable

Methane hydrates have been known since the 1930s, when natural gas companies found that their pipelines were sometimes clogged by a kind of ice composed of water and methane. Methane hydrates were later found in permafrost in the 1960s, and in the oceans, commonly on the edges of the continental shelves, but only at certain ocean pressures and temperatures. They are also thought to be found on other planets, including Mars.

When methane hydrates "melt", they release the methane trapped inside the ice, but because the methane was first trapped under pressure when the hydrate was formed, one cubic metre of solid methane hydrate will release 160 cubic metres of methane gas. That makes them either a potent energy source, or if they melt as the permafrost melts, a potent source of methane, which will act as a greenhouse gas.

But mining methane hydrates as an energy source, an option that is being explored by Japan among others, is technically difficult. Their location on the soft, sediment-loaded edges of the continental shelves makes them difficult to mine, and when they are disturbed, their crystal structure may suddenly dissociate and release the methane trapped inside.

This mechanism has been suggested as one reason why the largest landslide known to humankind, the Storegga Slide, was so destructive. The Storegga Slide took place about 8000 years ago, from an underwater location off the west coast of southern Norway.

The slides - there were three in total¬- sent a wall of water roaring out across the North Sea and Norwegian Sea. The evidence of the passage of the tsunami wave in Scotland that shows the wave reached heights of 3-6 metres in that region. One hypothesis for the slide was that an earthquake caused the methane hydrates in the region to become unstable and to explosively release their gas.

Computer simulations show surprising behaviour

Researchers at NTNU's Nanomechanical Lab and from the university's Department of Chemistry and their collaborators in China and the Netherlands are interested in understanding the relation between molecular structures and the mechanical stability of materials. Methane hydrates, with their ice lattice structure containing trapped molecules of methane, pose an intriguing three-dimensional and practical problem from this perspective.

In a paper published in the 2 November edition of Nature Communications, corresponding author Zhang and his colleagues describe how they used a computer simulation of two types of methane hydrates, monocrystalline hydrates and polycrystalline hydrates, to see what would happen if they were compressed or if pressures on the hydrates were suddenly released.

The researchers built their computer models using common molecular models for ice/water and methane, arranged as either monocrystalline or polycrystalline grains, and simulated the effect of applying forces to the collection of grains.

Maximum capacity found

The simulated hydrate structures were subjected to two different kinds of stress: tensile stress, or the forces they would experience as they were pulled apart, and compressive stress, or the forces they would experience if they were squashed by weight.

The simulations showed that the size of the crystals--what researchers call the grain size--that made up the hydrate structure had a great deal to say in terms of how the structure reacted to both kinds of stresses.

In both tensile and compression stress simulations, the surprising finding was that as the grain size got smaller, the hydrates first got stronger, able to tolerate both compression and tensile stress--but only until they reached a certain grain size. If the researchers conducted simulations on grain sizes smaller than those identified as the turning point, the hydrate actually got weaker.

The maximum capacity of the hydrates appears when the grain size is around 15 to 20 nm. This resembles the behaviour of polycrystalline metals, such as copper. However, this is the first time that researchers have seen this type of behaviour in methane hydrates as a material. The grain size-dependent strength and maximum capacity that the researchers found can be used in predicting and preventing the failure of hydrates in the future.

Instability can be triggered

This unexpected rapid weakening of the crystal structure as the grain size gets smaller has important implications for any work in areas where hydrates are found.

The researchers reported that the dissociation of methane hydrates can be triggered by the ground deformation caused by "earthquakes, storms, sea-level fluctuations or man-made disturbances (including well drilling and gas production from hydrate reservoirs)."

"This has an impact on these big issues," Zhang said. "Here we have taken one step forward, but of course there is a lot more work to be done."

Source : Key properties of methane hydrates found in permafrost and on the continental shelf illuminated Nature Communications. DOI: http://dx.doi.org/10.1038/NCOMMS9743