Science  11 Apr 2003:
Vol. 300, Issue 5617, pp. 223

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  1. IMAGES: Going Through Stages

    The first 2 months of pregnancy are when a human embryo takes shape. The Virtual Human Embryo project at Louisiana State University in Baton Rouge is creating a digital atlas for each of the 23 stages of this formative period. Each atlas is a database featuring computer-processed images of sectioned embryos from the Carnegie Collection, amassed over the last 115 years by the National Museum of Health and Medicine in Washington, D.C.

    The Web site provides working databases for two stages, 10 and 12. You can summon 3D reconstructions of the delicate embryos, flip through cross-sections, and study labeled structures. Above, developing blocks of muscle are visible along the back of this stage-10 embryo. Three completed databases can be ordered on CD or DVD for the cost of shipping, and the team plans to make all 23 available online as they are finished over the next 4 years. One objective is to encourage researchers to reexamine human embryology, says co-principal investigator John Cork. Much of what's in the textbooks was extrapolated from animals and is sometimes wrong, he says.

  2. EXHIBIT: Around the World in 1051 Days

    It was the moon landing of its day. Between 1768 and 1771, Captain James Cook and his ship, HMS Endeavour, circumnavigated the globe on the first exclusively scientific voyage. This new site from the Natural History Museum in London showcases more than 100 paintings of plant specimens plucked during Endeavour's stops in Tahiti, Australia, New Zealand, and other exotic destinations. Along with a gaggle of botanists, astronomers, and surveyors, the ship carried artist Sydney Parkinson, who painted most of the works exhibited here. Parkinson died of dysentery late in the voyage, and artists in England completed the rest of the paintings based on his sketches. The illustrations capture everything from lavish tropical vegetation, such as this Brazilian Bougainvillea spectabilis, to stalwart trees adapted to stormy Tierra del Fuego.

  3. RESOURCES: Keeping Up With SARS

    Moving fast and striking around the planet, severe acute respiratory syndrome (SARS) has already infected thousands of people and triggered warnings against traveling to Hong Kong and other epicenters of the outbreak. To keep track of this newly identified disease, visit the Web site for ProMED. Moderators of this global reporting system glean hundreds of press stories and news releases to compile reports about the disease's spread. Meanwhile, the official worldwide patient tally, broken down by country, is available at a site maintained by the World Health Organization, which has taken the lead in investigating and controlling the sometimes fatal illness.

    The U.S. Centers for Disease Control and Prevention (CDC) in Atlanta has lots of information tailored for doctors, hospitals, and travelers. Read or listen to press briefings by CDC director Julie Gerberding and other experts. For medical details from the frontlines and scientific speculation on the culprit, turn to The New England Journal of Medicine, which posted free, detailed reports from Hong Kong and Canada last week.

  4. DATABASES: Home Base for RNA

    Long dismissed as DNA's errand boys, RNA molecules have emerged as cellular big shots that catalyze reactions, throttle viruses, and help regulate genes. Scientists investigating these multitalented nucleic acids will find a trove of information on their structure and evolution at the Comparative RNA Web Site, curated by molecular biologist Robin Gutell of the University of Texas, Austin.

    The site focuses on ribosomal and transfer RNAs, which help build proteins, and the group I and II introns, which can act as catalysts. One highlight is the collection of secondary structure diagrams, which illustrate how more than 400 different varieties of RNA molecules twist, turn, and fold back on themselves. The section on nucleotide frequency and conservation compares RNA sequences within major groups of organisms, pinpointing stretches that change little during evolution and are usually associated with vital tasks. For each of these RNAs, summary tables show the amount of variation at different positions in the molecule. To track RNA evolution, you can superimpose the changes onto a phylogenetic tree.