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Categories: Chemistry: Organic Chemistry, Geoscience: Oceanography
Published Cutting-edge 'protein lawnmower' created



Scientists have designed the first synthetic protein-based motor which harnesses biological reactions to fuel and propel itself. 'Imagine if a Roomba could be powered only by the dirt it picks up,' says one of the authors of the study. The motor uses the digestive enzyme trypsin to cut the peptides and convert them into the energy it needs to propel itself.
Published Significant glacial retreat in West Antarctica began in 1940s



Among the vast expanse of Antarctica lies the Thwaites Glacier, the world's widest glacier measuring about 80 miles on the western edge of the continent. Despite its size, the massive landform is losing about 50 billion tons of ice more than it is receiving in snowfall, which places it in a precarious position in respect to its stability. Accelerating ice loss has been observed since the 1970s, but it is unclear when this significant melting initiated -- until now. A new study suggests that the significant glacial retreat of two glaciers on the west coast of Antarctica began in the 1940's, likely spurred by climate change.
Published The mutual neutralization of hydronium and hydroxide



Researchers have been able to directly visualize the neutral products of the mutual neutralization of hydronium and hydroxide, and report three different product channels: two channels were attributed to a predominant electron-transfer mechanism, and a smaller channel was associated with proton transfer. The two-beam collision experiment is an important step toward understanding the quantum dynamics of this fundamental reaction.
Published Barriers against Antarctic ice melt disappearing at the double



Undersea anchors of ice that help prevent Antarctica's land ice from slipping into the ocean are shrinking at more than twice the rate compared with 50 years ago, research shows. More than a third of these frozen moorings, known as pinning points, have decreased in size since the turn of the century, experts say. Further deterioration of pinning points, which hold in place the floating ice sheets that fortify Antarctica's land ice, would accelerate the continent's contribution to rising sea levels, scientists warn.
Published Chemists synthesize unique anticancer molecules using novel approach



Nearly 30 years ago, scientists discovered a unique class of anticancer molecules in a family of bryozoans, a phylum of marine invertebrates found in tropical waters. The chemical structures of these molecules, which consist of a dense, highly complex knot of oxidized rings and nitrogen atoms, has attracted the interest of organic chemists worldwide, who aimed to recreate these structures from scratch in the laboratory. However, despite considerable effort, it has remained an elusive task. Until now, that is. A team of chemists has succeeded in synthesizing eight of the compounds for the first time using an approach that combines inventive chemical strategy with the latest technology in small molecule structure determination.
Published Stronger storms free more nutrients from mud flats



If storms become stronger in the future due to climate change, more nitrogen may be released from the bottom of coastal seas.
Published Biggest Holocene volcano eruption found by seabed survey



A detailed survey of the volcanic underwater deposits around the Kikai caldera in Japan clarified the deposition mechanisms as well as the event's magnitude. As a result, the research team found that the event 7,300 years ago was the largest volcanic eruption in the Holocene by far.
Published Mercury levels in tuna remain nearly unchanged since 1971



Tuna is one of the most popular seafoods worldwide. But this protein-rich fish can build up high levels of methylmercury from feeding on contaminated prey, like smaller fish or crustaceans. Despite efforts to reduce mercury emissions into the environment, researchers report that levels in tuna appear to be unchanged since 1971. They warn that more aggressive emission reduction targets are needed to start nudging down tuna mercury levels.
Published Gulf corals still suffering more than a decade after Deepwater Horizon oil spill, scientists report



Deep-water corals in the Gulf of Mexico are still struggling to recover from the devastating Deepwater Horizon oil spill in 2010, scientists report at the Ocean Science Meeting in New Orleans. Comparing images of more than 300 corals over 13 years -- the longest time series of deep-sea corals to date -- reveals that in some areas, coral health continues to decline to this day.
Published Decline in microbial genetic richness in the western Arctic Ocean



Researchers analyzed archival samples of bacteria and archaea populations taken from the Beaufort Sea, bordering northwest Canada and Alaska. The samples were collected between 2004 and 2012, a period that included two years -- 2007 and 2012 -- in which the sea ice coverage was historically low. The researchers looked at samples taken from three levels of water: the summer mixed layer, the upper Arctic water below it and the Pacific-origin water at the deepest level. The study examined the microbes' genetic composition using bioinformatics and statistical analysis across the nine-year time span. Using this data, the researchers were able to see how changing environmental conditions were influencing the organisms' structure and function.
Published Viruses that can help 'dial up' carbon capture in the sea



Armed with a catalog of hundreds of thousands of DNA and RNA virus species in the world's oceans, scientists are now zeroing in on the viruses most likely to combat climate change by helping trap carbon dioxide in seawater or, using similar techniques, different viruses that may prevent methane's escape from thawing Arctic soil.
Published Giant Antarctic sea spiders reproductive mystery solved



Instead of carrying the babies until they hatched, as in most species of sea spiders, one parent (likely the father) spent two days attaching the eggs to the rocky bottom where they developed for several months before hatching as tiny larvae.
Published Anoxic marine basins are among the best candidates for deep-sea carbon sequestration



Anoxic marine basins may be among the most viable places to conduct large-scale carbon sequestration in the deep ocean, while minimizing negative impacts to marine life. As we explore ways to actively draw down the levels of carbon in the atmosphere, sending plant biomass to these barren, oxygen-free zones on the seafloor becomes an option worth considering.
Published Advanced artificial photosynthesis catalyst uses CO2 more efficiently to create biodegradable plastics



A research team that had previously succeeded in synthesizing fumaric acid using bicarbonate and pyruvic acid, and carbon dioxide collected directly from the gas phase as one of the raw materials, has now created a new photosensitizer and developed a new artificial photosynthesis technology, effectively doubling the yield of fumaric acid production compared to the previous method. The results of this research are expected to reduce carbon dioxide emissions and provide an innovative way to produce biodegradable plastics while reusing waste resources.
Published Beyond peak season: Bacteria in the Arctic seabed are active all year round



Researchers studied the composition and function of bacteria in the seabed off Svalbard, during alternating periods of polar night and midnight sun. To do this, they specially developed a sampling device, the Ellrott grab. In contrast with bacterial communities in the overlying water, the sediment bacteria hardly change with the seasons. This is probably due to the fact that in the seabed some hard-to-digest foods are available all year round.
Published Searching for clues in the history book of the ocean



New research has shown that the tropical subsurface ocean gained oxygen during the Paleocene-Eocene Thermal Maximum (commonly referred to as PETM). During this short-lived interval of time in Earth s history that occurred 56 million years ago the average temperatures rose by up to six degrees within a few thousand years.
Published With just a little electricity, researchers boost common catalytic reactions



A simple new technique could boost the efficiency of some key chemical processing, by up to a factor of 100,000, researchers report. The reactions are at the heart of petrochemical processing, pharmaceutical manufacturing, and many other industrial chemical processes.
Published Early-stage subduction invasion



Our planet's lithosphere is broken into several tectonic plates. Their configuration is ever-shifting, as supercontinents are assembled and broken up, and oceans form, grow, and then start to close in what is known as the Wilson cycle.
Published New 'time travel' study reveals future impact of climate change on coastal marshes



A new study offers a glimpse into the possible impact of climate change on coastal wetlands 50 years or longer into the future. Scientists are usually forced to rely on computer models to project the long-term effects of rising seas, but an unexpected set of circumstances enabled a real-world experiment along the Gulf Coast.
Published Microscopy: Overcoming the traditional resolution limit for the fast co-tracking of molecules



Researchers have developed an innovative method to simultaneously track rapid dynamic processes of multiple molecules at the molecular scale.