Oceans can store tremendous amounts of heat and are major players in Earth's heat-exchange mechanisms and climatic processes. Little is known about ocean circulation in the eastern and central parts of the tropical Atlantic Basin, but two oceanographic campaigns in 1999 and 2000, launched as part of the Equalant program by the Institute for Research and Development in Paris, have tracked zonal currents, in thermocline and subthermocline layers, between the Brazilian and African coasts. The physical data, including velocity, temperature and salinity, and chemical parameters, nutrient salts, dissolved oxygen, chlorofluorocarbons, have revealed new information about the eastward flow of currents in the equatorial Atlantic strip. The research team looked at the equatorial zone of warm water masses moving from the southern hemisphere and found, in the near-surface layers of the ocean, five currents: an equatorial undercurrent, the South and North equatorial undercurrents, and the North and South intermediate counter-currents.

OXFORD SPINOUT

Glycoform Ltd. is the latest company to be launched from Oxford University. It has expertise in identifying novel carbohydrate -- cell surface receptor-- binding properties to develop unique drug targeting systems. The company is developing the LEAPT -- Lectin Enzyme Activated Pro-drug Therapy -- technology based on the research of Ben Davis and Antony Fairbanks in Oxford's Chemistry Department. The company already has done specific targeting of glyco-proteins in liver cells, which could lead to a drug delivery method for highly toxic anti-cancer drugs. The company will forge partnerships with pharmaceutical and biotechnology companies to move the technology forward and also collaborate with other researchers to improve protein/antibody drugs.

NEW THEORY ON EARLY ANCESTORS

New research suggests our ancestors interbred with locals in the areas they settled as they moved out of Africa some 1.8 million years ago. University of Utah anthropology expert, Professor Henry Harpending, says this analysis of human genetic history, a collaborative effort involving some 20 researchers, deals a blow to the theory early people completely replaced local populations elsewhere in the world. Scientists can analyze ancient genetic mutations in modern people to learn how humans evolved and the size of the human population over time. Earlier studies mitochondrial DNA and microsatellites supported the replacement theory. The new study analyzed mutations called SNPs -- single nucleotide polymorphisms -- in DNA from the nucleus of human cells. It shows what appears to be a sharp reduction in the number of people when ancestors colonized Europe 40,000 years ago. Under the replacement theory there should have been an expansion of population size, the researchers said. Harpending says a possible explanation is a large population of humans migrated from Africa but kept largely to themselves with only limited mating with local populations. Only a few of the prehistoric European genes were then incorporated into the modern human genetic blueprint, giving a false impression the prehistoric human population collapsed or shrank in size.

DIAMONDS ARE TIME CAPSULES

A University of Maryland-led team of scientists has discovered the saying, "a diamond is forever" is true. They have found diamonds are natural time capsules, preserving information about the cycling of sulfur between Earth's crust, atmosphere and mantle 3 billion years ago. Diamonds from a region in Botswana, Africa, contain a distinctive ratio of three forms, or isotopes, of sulfur. This indicates the sulfur went through a nearly complete geochemical cycle, the researchers say. The cycle began when sulfur dioxide and hydrogen sulfide gases were spewed into the atmosphere by an ancient volcano. The sulfur-bearing gases reacted with ultraviolet light to produce the signature sulfur isotope in aerosols that floated back to Earth's surface and were incorporated in ancient sedimentary rocks as sulfides. The tectonic plate containing this sedimentary rock eventually moved downward, beneath another plate, into the underlying mantle. When diamonds formed in the mantle, the sulfides with their signature sulfur isotopes were trapped inside

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(EDITORS: For more information on OCEAN, contact Marie-Lise Sabrie at 33 1 48 03 75 36 or e-mail sabrie@paris.ird.fr. For GLYCOFORM, contact Jennifer Johnson at 01865 280839 or e-mail jennifer.johnson@isis.ox.ac.uk. For OUT OF AFRICA, Henry Harpending, (801) 582-7760 or (801) 581-3776, or e-mail harpend@xmission.com or henry.harpending@anthro.utah.edu, and for DIAMONDS, Lee Tune, (301) 405-4679 or ltune@accmail.umd.edu).