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Updated: 16 hours 6 min ago

Richard Lewis Arnowitt

6 October 2014

Richard Lewis Arnowitt

6 October 2014

Can battery technology advance rapidly to “transform the prosperity of the world”?

6 October 2014
A Wall Street Journal column and an Atlantic magazine report present starkly contrasting outlooks.

Can battery technology advance rapidly to “transform the prosperity of the world”?

6 October 2014
A Wall Street Journal column and an Atlantic magazine report present starkly contrasting outlooks.

Bio-inspired adhesive works underwater

6 October 2014

Ars Technica: Adhesives that form bonds while immersed in water would have many uses, especially in biomedical applications. To come up with such a substance, researchers have been studying sea-dwelling organisms, such as mussels and algae, whose secretions have naturally adhesive properties. Two different types of adhesive substances were found: One uses a chemical that links proteins together and is thus considered “sticky,” and the other uses an amyloid protein assembly that forms dense fibers. When combined, the sticky proteins enhanced the diameter of the fibers, which increased the surface contact area and improved adhesion. In addition, how the material interacts with different surfaces, such as silica, gold, and polystyrene, appears to depend on the interaction between the fibrous and sticky parts.

Bio-inspired adhesive works underwater

6 October 2014

Ars Technica: Adhesives that form bonds while immersed in water would have many uses, especially in biomedical applications. To come up with such a substance, researchers have been studying sea-dwelling organisms, such as mussels and algae, whose secretions have naturally adhesive properties. Two different types of adhesive substances were found: One uses a chemical that links proteins together and is thus considered “sticky,” and the other uses an amyloid protein assembly that forms dense fibers. When combined, the sticky proteins enhanced the diameter of the fibers, which increased the surface contact area and improved adhesion. In addition, how the material interacts with different surfaces, such as silica, gold, and polystyrene, appears to depend on the interaction between the fibrous and sticky parts.

Two studies focus on ocean waters as heat sink

6 October 2014

Science: Although Earth’s oceans are as important to global climate as the atmosphere, they have not been as well studied. Two areas of particular concern are the waters of the Southern Hemisphere and those of the deep ocean, below 2000 m. Paul Durack of Lawrence Livermore National Laboratory and colleagues used satellite measurements of sea-level height to estimate ocean temperature—as water warms, it expands. According to their model simulations, estimates of the heat stored in the upper 700 m of the ocean since 1970 have been too low, due largely to the poor sampling data from the Southern Hemisphere. Another group of researchers, led by William Llovel of the Jet Propulsion Laboratory, looked at warming in the deep ocean since 2005. Because most temperature data come from buoys, more is known about water temperature in the top 2000 m, and much less is known about the temperature of the rest of the ocean, which can descend as deep as 6000 m. Comparing the available data with global sea-level rise since 2005, the researchers estimate that the deep ocean has barely warmed over the past decade. Both studies point up the need for more data, which may soon be provided by a new fleet of research buoys, dubbed Deep Argo.

Two studies focus on ocean waters as heat sink

6 October 2014

Science: Although Earth’s oceans are as important to global climate as the atmosphere, they have not been as well studied. Two areas of particular concern are the waters of the Southern Hemisphere and those of the deep ocean, below 2000 m. Paul Durack of Lawrence Livermore National Laboratory and colleagues used satellite measurements of sea-level height to estimate ocean temperature—as water warms, it expands. According to their model simulations, estimates of the heat stored in the upper 700 m of the ocean since 1970 have been too low, due largely to the poor sampling data from the Southern Hemisphere. Another group of researchers, led by William Llovel of the Jet Propulsion Laboratory, looked at warming in the deep ocean since 2005. Because most temperature data come from buoys, more is known about water temperature in the top 2000 m, and much less is known about the temperature of the rest of the ocean, which can descend as deep as 6000 m. Comparing the available data with global sea-level rise since 2005, the researchers estimate that the deep ocean has barely warmed over the past decade. Both studies point up the need for more data, which may soon be provided by a new fleet of research buoys, dubbed Deep Argo.

Measuring atmospheric carbon dioxide from space

6 October 2014
If we can account for the confounding effects of aerosols, satellite-based measurements of CO2 will improve our understanding of Earth’s carbon cycle.

Emergent effect creates quasi-Majorana particles

6 October 2014

Nature: Particles that are their own antiparticles were predicted by Ettore Majorana in 1937. None have been found in particle-physics experiments so far, but hints of Majorana-like quasiparticles have been seen in a condensed-matter system of strongly interacting electrons. Further, stronger evidence of the quasiparticles comes from a new experiment performed by Ali Yazdani of Princeton University and his colleagues. To create the quasiparticle, they placed a chain of iron atoms on top of a superconductor in such a way that the electrons in the iron atoms paired off. Each pair coordinated spins so that one of the electrons acted like a positron (the antielectron particle). The arrangement left unpaired electrons at both ends of the chain, which forced those two electrons to individually behave as both an electron and a positron. The finding strengthens the idea that true Majorana particles could exist outside of superconductors.

Emergent effect creates quasi-Majorana particles

6 October 2014

Nature: Particles that are their own antiparticles were predicted by Ettore Majorana in 1937. None have been found in particle-physics experiments so far, but hints of Majorana-like quasiparticles have been seen in a condensed-matter system of strongly interacting electrons. Further, stronger evidence of the quasiparticles comes from a new experiment performed by Ali Yazdani of Princeton University and his colleagues. To create the quasiparticle, they placed a chain of iron atoms on top of a superconductor in such a way that the electrons in the iron atoms paired off. Each pair coordinated spins so that one of the electrons acted like a positron (the antielectron particle). The arrangement left unpaired electrons at both ends of the chain, which forced those two electrons to individually behave as both an electron and a positron. The finding strengthens the idea that true Majorana particles could exist outside of superconductors.

Snowflake-like network design minimizes downtime and repair difficulty

6 October 2014

New Scientist: Large networks such as the power grid and the internet make use of redundancy to reduce the effects of damage to the network. Redundancy is generally expensive and can be difficult to maintain, but the cheaper alternative of fixing broken connections as needed can leave areas without network connection until they are repaired. To minimize the difficulty of making repairs, Robert Farr of the London Institute for Mathematical Sciences and his colleagues have determined that the ideal network design is a snowflake-like pattern. Starting with an arrangement of square or triangular nodes, they found that the best way to connect them was to have primary branches that have no more than two levels of branches below them. That topology allows each node to be connected on all but one side, meaning that connection failures were contained and that repairs were easy to make. Farr's team now hopes to apply the idea to real-world situations to determine how adaptable it is to changing conditions.

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