Science  03 Jun 2005:
Vol. 308, Issue 5727, pp. 1387

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  1. RESOURCES: Digging Up Weeds

    It may look pretty, but the invasive purple loosestrife (Lythrum salicaria) is the scourge of American wetlands. The immigrant from Europe and Asia is crowding out native species of grasses and sedges and threatening some endangered plants and animals. Although it focuses on one part of the United States, the Southwest Exotic Plant Information Clearinghouse is a good general source of facts about non-native plants such as purple loosestrife that are growing amok. Sponsored by federal agencies and Northern Arizona University, the database collects backgrounders on more than 300 invasive species, from the common dandelion to the ultracompetitive medusahead grass. Another feature lets users map reports of the species in the Southwest.

  2. FUN: In Tune With Physics

    To explain relativity, Einstein lectured and wrote books and papers, but he never cut an album. He might have missed an opportunity. Setting physics ideas to music can amplify students' learning and enjoyment, according to Walter Smith, a physics professor at Haverford College in Pennsylvania. Smith's Web site caches lyrics sheets for hundreds of physics tunes, including many compositions he co-wrote. There are also sound files for more than 80 songs and some chord charts so you can play along. Einstein might not have donned lederhosen and yodeled about the speed of light, but other famous physicists have channeled their musical muse. Take the Englishman J. J. Thomson, who discovered the electron in 1897 and penned “Ions Mine” to the tune of “Oh My Darling Clementine”:

    In the dusty lab'ratory, ‘Mid the coils and wax and twine, There the atoms in their glory, Ionize and recombine.

  3. EDUCATION: Genetics Made Clear

    From stem cells to gene chips, from prions to cloning, genetics and biotechnology can look forbiddingly complex to high school and lower-division college students. Beginners can ease into these subjects at the Genetic Science Learning Center, a graphics-rich tutorial from the University of Utah in Salt Lake City. Primers step through topics from DNA structure to the different types of stem cells; compared to embryonic stem cells, those from adults so far can't seem to form the same range of tissues. Animations illustrate techniques such as microarray analysis and investigate questions such as how cystic fibrosis upsets the ion balance in lung cells.

  4. RESOURCES: Equation Central

    Need the solution for the generalized Abel integral equation of the second kind? Stumped by the FitzHugh-Nagumo equation, which can describe heat transfer and the voltage across a cell membrane? Check out EqWorld, edited by Andrei Polyanin of the Russian Academy of Sciences in Moscow. For hundreds of equations, EqWorld gathers solutions that had been squirreled away in handbooks, journals, and other sources. The site includes ordinary and partial differential equations, integrals, and other types.

  5. DATABASE: Scanning Species

    Many taxonomists want to expedite the often laborious task of identifying specimens by using a unique DNA sequence, or bar code, to recognize each species (Science, 18 February, p. 1037). At the Web headquarters of the Barcode of Life Initiative, hosted by the University of Guelph in Canada, visitors can read up on the concept, which proponents are hoping will accelerate the cataloging of Earth's disappearing life forms. The site already holds codes for more than 13,000 animal species. The codes, based on different sequences of the cytochrome c oxidase I gene in mitochondria, encompass 260 species of North American birds and a selection of insects, such as the Halysidota tesselaris moth. Users can compare a bar code from their specimen to the entries in the database. The site will soon add about one-fifth of North American butterflies and moths, says curator Paul Hebert.