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Laptop computers have become commonplace in K-12 and college classrooms. With that, educators now face a critical decision. Should they embrace computers and put technology at the center of their instruction? Should they allow students to decide for themselves whether to use computers during class? Or should they ban screens altogether and embrace an unplugged approach? The right way forward is unclear, especially at colleges that pride themselves on connectivity. The personal computer is a powerful tool. It can efficiently store and enhance student work; it can also effectively transport a student's attention away from that work. To determine the impact of laptop usage on student performance, the authors conducted a randomized controlled trial among undergraduate students at the United States Military Academy, widely known by the name of its location in West Point, New York. In the study, they designated who was allowed to use and who was prohibited from using laptops or tablets to take notes in class. They found that allowing any computer usage in the classroom--even with strict limitations--reduces students' average final-exam performance by roughly one-fifth of a standard deviation. This effect is as large as the average difference in exam scores for two students whose cumulative GPAs at the start of the semester differ by 0.17 grade points on a standard 0-4.0 scale. Importantly, these results are from a highly competitive institution where student grades directly influence employment opportunities at graduation--in other words, a school where the incentives to pay attention in class are especially high.

Tests were conducted on the performance of coils based on long length, surface-coated, react-before-wind BSCCO-2212 high temperature conductors for such applications as transformer windings and nuclear magnetic resonance insert magnets. The coils functioned properly under thermal cycling and other tests. Superconductor costs for magnet systems may be reduced by half by using BSCCO-2212 augmented by BSCCO-2223 conductors.

Intermagnetics has developed high temperature superconducting coils for the Navy's homopolar motor/generator program. Two coil sizes were employed and conductor winding, epoxy impregnation and insulation considerations were evaluated using a series of small test coils. The three react-and-wind type coils produced are surface coated BSCCO-2212, monocore BSCCO-2223 and multifilamentary BSCCO-2223.

An innovative dip-coat process is use to prepare coated BSCCO-2212 high temperature superconductors. Dip-coating is carried out by drawing thick silver tapes through slurries of BSCCO-2212 powder produced by aerosol or spray pyrolysis methods. The resulting tapes exhibit critical current densities of up to 5,000 amperes-per-centimeter-squared at 77 degrees Kelvin in zero applied magnetic field.

An applied theoretical perspective and a set of survey methods is outlined to move beyond the inherent limitations of unemployment rates and other census data used to infer availability and prevailing wage rates of a community's workforce. When these methods were applied to Kansas in 2001, it was found that more than 7 percent of Kansas of working age were unemployed in some manner but was available for job opportunities.

Water transfers and water markets have become the principal policy mechanisms for reallocating water resources to areas of greatest demand in the western United States . Comparisons and contrasts between our two study areas - the Grand Valley of western Colorado and the San Joaquin Valley portion of Kern County , California - suggest that the ability to implement reforms in regional water uti lization patterns is influenced by specific social and historical contexts within which local populations define and utilize scarce water resources . Consistent with previous literature , the current research found that residents of a water - exporting area were more likely to oppose water transfers than were residents of a water - importing area . Regardless of local context , however , residents in these two distinct areas of the West had strong reservations about free markets as a means of allocating water . [ABSTRACT FROM AUTHOR]