Solving a mystery that has puzzled scientists for decades, MIT and Harvard researchers have discovered the final piece of the synthesis pathway of vitamin B12-the only vitamin synthesized exclusively by microorganisms.

B12, the most chemically complex of all vitamins, is essential for human health. Four Nobel Prizes have been awarded for research related to B12, but one fragment of the molecule remained an enigma-until now.

Identification of the oldest preserved pieces of Earth's crust in southern Greenland has provided evidence of active plate tectonics as early as 3.8 billion years ago, according to a report by an international team of geoscientists in the March 23 edition of Science magazine.

The finding pushes back the date of continent-forming processes previously determined as 2.5 billion years ago to a much earlier era considerably closer to Earth's formation some 4.5 billion years ago. Geochemical analysis of rocks has previously suggested an earlier date for plate tectonics, but this is the first study to find physical evidence of tectonics among Earth's oldest known rock structures, according to Hubert Staudigel of Scripps Institution of Oceanography at UC San Diego.

The cancer drug asparaginase fails to help cure some children with acute lymphoblastic leukemia (ALL) because molecules released by certain cells in the bone marrow counteract the effect of that drug, according to investigators at St. Jude Children's Research Hospital.

The researchers showed that mesenchymal cells in the bone marrow create a protective niche for leukemic cells by releasing large amounts of asparagine, an amino acid that nearby leukemic cells must have to survive but do not make efficiently. This extra supply of asparagine helps leukemic cells survive treatment with asparaginase, a drug that normally would deplete their supply of this vital nutrient, the researchers reported.

For parents, 8 million cases of acute middle ear infections every year add up to a lot of sleepless nights and trips to the pediatrician. But new research from a collaboration between Rockefeller University and St. Jude Children’s Hospital could change all that.

In the March 23 issue of PLoS Pathogens, Rockefeller’s Vincent A. Fischetti and colleagues at St. Jude show that middle ear infections in mice can be prevented by giving the mice a lysin – a protein derived from a virus that infects bacteria. The new technology may prevent children with the flu from developing secondary ear infections and would be an attractive alternative to traditional antibiotics, to which bacteria are rapidly becoming resistant.

A new study out of Alaska points out the impacts of climate change on marine ecosystems, and the need for increased research and stronger science based management to address future concerns.

Studies by a team of scientists at the North Pacific Universities Marine Mammal Research Consortium http://www.marinemammal.org/ revealed that a sudden ocean climate change 30 years ago changed today’s Alaska marine ecosystems, and may be a leading factor in the decline of Alaska’s endangered western stock of Steller sea lions.

The first published study on the environmental impact of manufactured nanoparticles on ordinary soil showed no negative effects, which is contrary to concerns voiced by some that the microscopic particles could be harmful to organisms.

Scientists added both dry and water-based forms of manufactured fullerenes - nanosized particles also known as buckyballs - to soil. The nanoparticles didn't change how the soil and its microorganisms functioned, said Ron Turco, a Purdue University soil and environmental microbiologist.