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If you choose to follow any links to the complete text of articles listed below, you will be leaving the Strategian Web site. If you wish to return to this page from the Web page you are sent to, please use the Back option of your browser. Feature Articles: Craig S. Lent Molecular Electronics: Bypassing the Transistor Paradigm. (... a short overview of recent and current work in the emerging field of molecular electronics. Current computers use different combinations of binary numbers [a number system that has 2 as its base] to represent information [different numbers, letters, and other characters]. These combinations of the binary numbers--1 and 0--are encoded as the on and off states of an electrical switch--today, that switch is a transistor. Replicating this technology at the level of the molecule, however, runs into a number of difficulties. The greatest of these difficulties involves the amount of heat generated by a transistor the size of a single molecule; if such a transistor could be created, it would melt as soon as it was turned on from the heat it generated. To get around these physical limits, the Quantum-dot Cellular Automata [QCA] paradigm has been developed which retains the notion of a binary representation of information, but this binary information is stored in the charge configuration within a cell rather than in the on/off state of a current switch. Each binary number is represented by one cell, and electrical current does not flow between cells. Rather, the Coulomb interaction between cells is exploited, which tends to induce the same state in neighboring cells. In that way, different combinations of binary numbers--represented by different combinations of single cells [and each cell is a single molecule]--can again represent different numbers, letters, and so on. In this way, the function of modern transistors can theoretically be done at the level of single molecules. Much remains to be done and overcome before the QCA approach to molecular electronics can become a reality though work on many of the challenges is currently underway. Other keywords and phrases -- energy dissipation, Fehlner, Marya Lieberman, metal cluster carboxylates, ruthenium -- from the text of the article) Science Volume 288, Number 5471 (June 2, 2000): 1597, 1599. Other Articles of Note: Alan K. Knapp, John M. Blair, John M. Briggs, Scott L. Collins, David C. Hartnett, Loretta C. Johnson, and E. Gene Towne The Keystone Role of Bison in North American Tallgrass Prairie - Bison Increase Habitat Heterogeneity and Alter a Broad Array of Plant, Community, and Ecosystem Processes. (... a review of research efforts on the interactions between the North American bison and tallgrass prairie that have taken place since the early 1990's at the Konza Prairie Research Natural Area of northeastern Kansas USA--the largest tract of unplowed tallgrass prairie in North America dedicated to research. The authors conclude that much as fire is now recognized as an essential component of tallgrass prairie management, the need for reintroducing the forces of large ungulate [hoofed mammals like bison] herbivory [grazing of green plants] to this grassland is evident. It is the interaction of ungulate grazing activities and fire, operating in a shifting mosaic across the landscape, that is key to conserving and restoring the biotic integrity of the remaining tracts of tallgrass prairie. Other keywords and phrases -- buffalo, burn, burned, burning, carcass, carcasses, cattle, grazed, keystone species, nutrient cycling, nutrient redistribution, plant response, unburned, ungrazed, wallowing -- from the text of the article; see the bibliography) BioScience Volume 49, Number 1 (January 1999): 39-50. Mary M. Woodsen Cities Under Seige. (... a brief article describing the Asian longhorned beetle and the damage it can cause to trees. The author states unlike the most recent national pest threat [in the United States]--the gypsy moth--Asian longhorneds don't just weaken trees, they kill them. And the only way to control the pests is to take down infested trees. To date, these beetles have been found in and around New York City and Chicago, and researchers and foresters are working to control the spread of the beetles and find some widespread way to kill them. See the primer on Asian longhorned beetles on page 8. Other keywords and phrases -- cut down, cutting, eradicate, eradication, forest, starry sky beetle, suburb, suburban, urban -- from the text of the article) American Forests Volume 106, Number 2 (Summer 2000): 7-9. Hans von Storch and Nico Stehr Climate Change in Perspective: Our Concerns About Global Warming have an Age-Old Resonance. (... a short, interesting commentary that gives an historical perspective to human concerns about natural and/or human-produced changes to Earth's climate. The authors briefly trace concerns about climate change from the Middle Ages to today. The authors have a distinct opinion, and they state that although most of the historical concerns over climate turned out to be exaggerated, we are not claiming that the present concept of global warming is flawed. We are convinced that greenhouse gases are accumulating in the air, and strongly believe that near-surface temperatures are rising in response. But we are not convinced that present and future climate change will have a significant impact on society and global ecosystems. Other keywords and phrases -- greenhouse effect -- from the text of the article) Nature Volume 405, Number 6787 (June 8, 2000): 615. How to find the above journals, magazines, and other publications? See Step 3: Locate of the Information Strategy for details. Questions about any or all of the above? Please let me know. |
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