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The forces that drove rock uplift of the low-relief, high-elevation, tectonically stable Colorado Plateau are the subject of long-standing debate. While the adjacent Basin and Range province and Rio Grande rift province underwent Cenozoic shortening followed by extension, the plateau experienced ∼2 km of rock uplift without significant internal deformation. Here we propose that warming of the thicker, more iron-depleted Colorado Plateau lithosphere over 35–40 Myr following mid-Cenozoic removal of the Farallon plate from beneath North America is the primary mechanism driving rock uplift. In our model, conductive re-equilibration not only explains the rock uplift of the plateau, but also provides a robust geodynamic interpretation of observed contrasts between the Colorado Plateau margins and the plateau interior. In particular, the model matches the encroachment of Cenozoic magmatism from the margins towards the plateau interior at rates of 3–6 km Myr-1 and is consistent with lower seismic velocities and more negative Bouguer gravity at the margins than in the plateau interior. We suggest that warming of heterogeneous lithosphere is a powerful mechanism for driving epeirogenic rock uplift of the Colorado Plateau and may be of general importance in plate-interior settings. [ABSTRACT FROM AUTHOR]

We present a simple modular landscape simulation model that is based on a watershed modeling framework in which different sets of processes occurring in a watershed can be simulated separately with different models. The model consists of three loosely coupled submodels: a rainfall-runoff model (TOPMODEL) for runoff generation in a subwatershed, a nutrient model for estimation of nutrients from nonpoint sources in a subwatershed, and a stream network model for integration of point and nonpoint sources in the routing process. The model performance was evaluated using monitoring data in the watershed of the Patuxent River, a tributary to the Chesapeake Bay in Maryland, from July 1997 through August 1999. Despite its simplicity, the landscape model predictions of streamflow, and sediment and nutrient loads were as good as or better than those of the Hydrological Simulation Program-Fortran model, one of the most widely used comprehensive watershed models. The landscape model was applied to predict discharges of water, sediment, silicate, organic carbon, nitrate, ammonium, organic nitrogen, total nitrogen, organic phosphorus, phosphate, and total phosphorus from the Patuxent watershed to its estuary. The predicted annual water discharge to the estuary was very close to the measured annual total in terms of percent errors for both years of the study period (≤2%). The model predictions for loads of nutrients were also good (20-30%) or very good (<20%) with exceptions of sediment (40%), phosphate (36%), and organic carbon (53%) for Year 1. [ABSTRACT FROM AUTHOR]

The Cosmic Ray Observatory Project (CROP) at University of Nebraska/Lincoln and the Washington Area Large-scale Time coincidence Array (WALTA) at University of Washington/Seattle are among several outreach projects siting cosmic-ray detectors at local high schools in cities around North America, to study the origins and interactions of high-energy cosmic rays. In a collaboration between QuarkNet, the outreach program based at Fermilab, CROP, and WALTA, a low-cost data acquisition electronics card has been developed to collect and synchronize the data from each detector site. The cost per card is under US$500 for parts (for 15 boards), functionally replacing much more expensive electronics crates and modules at each high school site. The card has four analog discriminator inputs for photomultiplier tube signals, a four-channel time-to-digital converter (TDC) for local coincidence and time-over-threshold measurements with ∼ 1 ns resolution, programmable trigger logic via a CPLD and microcontroller, and a built-in low-cost GPS receiver/antenna module (via external cable) to provide event trigger time stamps with 50 ns accuracy. Temperature sensors and a barometer are also integrated to record environmental data along with the counter data. The card connects to any PC or laptop via a standard RS-232 serial port for data output and control. The microcontroller and CPLD are field programmable and thus make the card functionality flexible and easy to upgrade. [ABSTRACT FROM AUTHOR]

Reports experimental measurements of neutron production from collisions of neutron beams with polyethylene blocks simulating tissue at the Los Alamos National Laboratory Neutron Science Center (LANSCE) in New Mexico. Experimental details; Results from the neutron bombardment of polyethylene at LANSCE.

The article focuses on the conceptual issues in the development of a taxonomy for special education in the U.S. The author implies that the assumption on which this presentation rests is that a taxonomy of special education is a practical tool. Another applied consideration is the value of a simple taxonomy as an aid in communication. A practical problem in instruction is deciding what to do with children who have several handicaps. The author added that a taxonomy of instruction is not necessarily applicable to post-instructional matters.

James Fenimore Cooper's Leatherstocking Tales have achieved canonical literary status in the US academy and provide a representative example of the frontier tradition in American writing. Through a close reading of Cooper's first romance, I argue that America's longstanding frontier narrative is predicated on the cultural projection of the able-bodied hero. In The Pioneers, Cooper relies on dueling constructions of disability and able-bodiedness to distinguish his white hero from his friend and Native American counterpart, Chingachgook. While Chingachgook's disability provides the logic for his eventual suicide and removal from the narrative, Natty Bumppo's strength of character becomes registered through the physical perfection of his body. In celebrating Natty Bumppo's passage from old age in The Pioneers to new youth in The Deerslayer, the critical tradition surrounding the Leatherstocking series has tacitly endorsed Cooper's corporeal hierarchy, suggesting that the myth of the American frontier relies upon a much deeper myth of American ability. [ABSTRACT FROM AUTHOR]

Comments on the U.S.-based Society of Motion Picture and Television Engineers' plan to combine the Advanced Motion Imaging Conference (AMIC) with the Video Services Forum Conference. Concern on the failure of the 2004 AMIC to reach the predicted attendance and the revenue target; Potential benefit of the move to both conferences.

The fluxes and concentrations of materials from two contiguous second-order watersheds in the Coastal Plain of Maryland, U.S.A. were measured for six years prior to and six years subsequent to the formationof a 1.25 ha beaver pond near the bottom of one of the watersheds. The watersheds have a clay aquiclude and were equipped with V-notch weirs and continuous volume-integrating water samplers. The beaver pondreduced annual discharge of water, total-N, total-P, dissolved silicate, TOC, and TSS by 8, 18, 21, 32, 28, and 27%, respectively. Most of the total-N reduction was due to increased retention of nitrate in the winter and spring and TON in the winter and summer. Most of the total-P reduction was the result of retention of both TPi and TOP in the winter and summer. Dissolved silicate retention peaked in the spring, while TOC and TSS retention peaked in the winter. Prior to the formation of the beaver pond, concentrations of TON, TPi, TOP, TOC, andTSS had highly significant correlations with stream discharge, especially in the winter, but subsequent to the pond there was little or no relationship between these concentrations and stream discharge. However, concentrations of nitrate in the spring and ammonium in the summer were highly correlated with stream discharge both before and after the formation of the beaver pond and regressions of discharge versus concentrations of these nutrients explained more of the variation in concentrations after the formation of the pond. [ABSTRACT FROM AUTHOR]

Total suspended sediment (TSS) concentrations and their nutrient composition were studied in discharges from seven contiguous small watersheds on the Atlantic Coastal Plain in Maryland for up to 22 yr. All watersheds were equipped with V-notch weirs and volume-integrating, flow-proportional samplers. Spot samples were also taken for analysis of TSS concentrations and the composition of dissolved and particulate nutrients at known water discharge rates. Interannual variations inannual and seasonal precipitation during this study spanned approximately the range of 160-yr weather records in the vicinity. Mean annual TSS fluxes were 263, 546, 134, and 92 kg ha-'for the area-weighted mean of the overall Rhode River watershed, and for subwatersheds thatwere primarily-cropland, completely forested, and grazed, respectively. TSS fluxes were highest in the summer, followed by spring, winter, and fall. Regressions of TSS flux vs. precipitation were used to calculate TSS fluxes for seasons and years with average, above and below the average precipitation. TSS flux from the Rhode River watershed was 12-fold higher in very wet years than in very dry years and 271-fold higher in very wet summers than in very dry summers. At base flow, TSS had high nutrient content, but as flow rates increased TSS nutrient content rapidly declined. At base flow, most of the total-P, TPi, TKN, and organic-C was in the dissolved phase, while at higher flows, most of these nutrients were in the TSS phase. [ABSTRACT FROM AUTHOR]