Status Report on the Low-Energy Demonstration Accelerator (LEDA)

The 75-keV injector and 6.7-MeV RFQ that comprise the first portion of the cw, 100-mA proton linac for the accelerator production of tritium (APT) project have been built and operated. The LEDA RFQ has been extensively tested for pulsed and cw output-beam currents <=100 mA. Up to 2.2 MW of cw rf power from the 350-MHz rf system is coupled into the RFQ, including 670 kW for the cw proton beam. The emittance for a 93-mA pulsed RFQ output beam, as determined from quadrupole-magnet-scan measurements, is ex x ey = 0.25 x 0.31 (pi mm mrad)2 [rms normalized]. A follow-on experiment, to intentionally introduce and measure beam halo on the RFQ output beam, is now being installed.Comment: Paper TUD14 for the XX International Linac Conference (LINAC2000), 3 pages, 10 figure

Policy reform and farmers' wheat allocation in rural China: a case study

Market-oriented policy reforms often have important effects on farm-level grain production and utilisation decisions in developing countries. China’s grain farmers are of particular interest because of China’s importance in world grain markets and because of China’s recent major agricultural policy advances and retrenchments. An empirical evaluation of market liberalisation among farmers located in two provinces in China on farm-level wheat consumption, market sales and on-farm storage during 1994 is presented. The results indicate that policymakers should account for such changes in farm household behaviour in designing and assessing the consequence ofmarket liberalisation programs for agricultural sectors in developing countries.China, grain storage, household allocation decisions, procurement quotas, wheat, Crop Production/Industries,

Heat and spin transport in a cold atomic Fermi gas

Motivated by recent experiments measuring the spin transport in ultracold unitary atomic Fermi gases (Sommer et al., 2011; Sommer et al., 2011), we explore the theory of spin and heat transport in a three-dimensional spin-polarized atomic Fermi gas. We develop estimates of spin and thermal diffusivities and discuss magnetocaloric effects, namely the the spin Seebeck and spin Peltier effects. We estimate these transport coefficients using a Boltzmann kinetic equation in the classical regime and present experimentally accessible signatures of the spin Seebeck effect. We study an exactly solvable model that illustrates the role of momentum-dependent scattering in the magnetocaloric effects.Comment: 18 pages, 6 figures, slight notation changes from previous versio

Biotech Food Labeling and Consumer Response: An Analysis of the Effects of Voluntary rBGH-labels on the Market for Fluid Milk

Consumer/Household Economics,

The Contribution of the Minimum Wage to U.S. Wage Inequality over Three Decades: A Reassessment

We reassess the effect of state and federal minimum wages on U.S. earnings inequality, attending to two issues that appear to bias earlier work: violation of the assumed independence of state wage levels and state wage dispersion, and errors-in-variables that inflate impact estimates via an analogue of the well known division bias problem. We find that the minimum wage reduces inequality in the lower tail of the wage distribution (the 50/10 wage ratio), but the impacts are typically less than half as large as those reported in the literature and are almost negligible for males. Nevertheless, the estimated effects extend to wage percentiles where the minimum is nominally non-binding, implying spillovers. We structurally estimate these spillovers and show that their relative importance grows as the nominal minimum wage becomes less binding. Subsequent analysis underscores, however, that spillovers and measurement error (absent spillovers) have similar implications for the effect of the minimum on the shape of the lower tail of the measured wage distribution. With available precision, we cannot reject the hypothesis that estimated spillovers to non-binding percentiles are due to reporting artifacts. Accepting this null, the implied effect of the minimum wage on the actual wage distribution is smaller than the effect of the minimum wage on the measured wage distribution.Wage structure, inequality, minimum wage

Giving the Spoon Back: Higher Teacher Expectations of Achievement for Students Who Are Deaf

This single case study examined a Deaf teacher’s behaviors and beliefs that reflect her expectations of her deaf students. Primary modes of communication used were American Sign Language and written English. Data were collected via videotaped observations and interviews. Analysis was done by coding utterances of the participants using a deductive framework and using an inductive approach to find patterns among the coded utterances. Teacher behavior and student reactions revealed high expectations for student achievement. The overarching factor that reflected teacher expectations was the positive classroom climate established by the teacher. Recommendations for further research to examine teacher expectations with other settings and participants are include

GOVERNMENT POLICIES AND ON-FARM WHEAT ALLOCATION IN RURAL CHINA

Market-oriented policy reforms have potentially important effects on farm-level grain production and utilization decisions in developing countries. This paper provides an empirical evaluation of the potential effects of market liberalization in China on farm-level wheat consumption, market sales, and on-farm storage. The results indicate that price changes have economically important impacts on utilization decisions by farm families through both income and substitution effects and that off- farm income also appears to be significant. The potential to earn off-farm income is also shown to be an important factor in grain utilization decisions. Storage is affected by government procurement policies as well as by more traditional food and income security considerations. The results indicate that policy makers should account for such changes in farm household behavior in designing and assessing the consequence of market liberalization programs for agricultural sectors in developing countries.China, wheat, grain storage, procurement quotas, household allocation decisions, Agricultural and Food Policy, Q18,