Parent and Student Voices on the First Year of the DC Opportunity Scholarship Program

In the 50 years since economist Milton Friedman published “The Role of Government in Education” scholars and policy makers have been debating how parental choice through market mechanisms can and does operate in education. Market “optimists” argue that education is a service that can be produced under a variety of arrangements and that parents are natural education consumers. Market “pessimists” argue that education is a public good that should be produced in government-run schools, and that school choice programs suffer “market failure” because only advantaged families will have the resources and experience to choose effectively

Highlights of experience with a flexible walled test section in the NASA Langley 0.3-meter transonic cryogenic tunnel

The unique combination of adaptive wall technology with a contonuous flow cryogenic wind tunnel is described. This powerful combination allows wind tunnel users to carry out 2-D tests at flight Reynolds numbers with wall interference essentially eliminated. Validation testing was conducted to support this claim using well tested symmetrical and cambered airfoils at transonic speeds and high Reynolds numbers. The test section hardware has four solid walls, with the floor and ceiling flexible. The method of adapting/shaping the floor and ceiling to eliminate top and bottom wall interference at its source is outlined. Data comparisons for different size models tested and others in several sophisticated 2-D wind tunnels are made. In addition, the effects of Reynolds number, testing at high lift with associated large flexible wall movements, the uniqueness of the adapted wall shapes, and the effects of sidewall boundary layer control are examined. The 0.3-m TCT is now the most advanced 2-D research facility anywhere

Predictive wall adjustment strategy for two-dimensional flexible walled adaptive wind tunnel: A detailed description of the first one-step method

Following the realization that a simple iterative strategy for bringing the flexible walls of two-dimensional test sections to streamline contours was too slow for practical use, Judd proposed, developed, and placed into service what was the first Predictive Strategy. The Predictive Strategy reduced by 75 percent or more the number of iterations of wall shapes, and therefore the tunnel run-time overhead attributable to the streamlining process, required to reach satisfactory streamlines. The procedures of the Strategy are embodied in the FORTRAN subroutine WAS (standing for Wall Adjustment Strategy) which is written in general form. The essentials of the test section hardware, followed by the underlying aerodynamic theory which forms the basis of the Strategy, are briefly described. The subroutine is then presented as the Appendix, broken down into segments with descriptions of the numerical operations underway in each, with definitions of variables

Can retinal ganglion cell dipoles seed iso-orientation domains in the visual cortex?

It has been argued that the emergence of roughly periodic orientation preference maps (OPMs) in the primary visual cortex (V1) of carnivores and primates can be explained by a so-called statistical connectivity model. This model assumes that input to V1 neurons is dominated by feed-forward projections originating from a small set of retinal ganglion cells (RGCs). The typical spacing between adjacent cortical orientation columns preferring the same orientation then arises via Moir\'{e}-Interference between hexagonal ON/OFF RGC mosaics. While this Moir\'{e}-Interference critically depends on long-range hexagonal order within the RGC mosaics, a recent statistical analysis of RGC receptive field positions found no evidence for such long-range positional order. Hexagonal order may be only one of several ways to obtain spatially repetitive OPMs in the statistical connectivity model. Here, we investigate a more general requirement on the spatial structure of RGC mosaics that can seed the emergence of spatially repetitive cortical OPMs, namely that angular correlations between so-called RGC dipoles exhibit a spatial structure similar to that of OPM autocorrelation functions. Both in cat beta cell mosaics as well as primate parasol receptive field mosaics we find that RGC dipole angles are spatially uncorrelated. To help assess the level of these correlations, we introduce a novel point process that generates mosaics with realistic nearest neighbor statistics and a tunable degree of spatial correlations of dipole angles. Using this process, we show that given the size of available data sets, the presence of even weak angular correlations in the data is very unlikely. We conclude that the layout of ON/OFF ganglion cell mosaics lacks the spatial structure necessary to seed iso-orientation domains in the primary visual cortex.Comment: 9 figures + 1 Supplementary figure and 1 Supplementary tabl

Family Reflections on the District of Columbia Opportunity Scholarship Program: Final Summary Report

During the spring of 2004, the first federally funded voucher program – the District of Columbia Opportunity Scholarship Program (OSP) - was established. The School Choice Demonstration Project (SCDP) recognized that publicly-funded school vouchers represent a relatively new and unstudied approach to school choice and education reform. To address this need, the SCDP requested and received funding from the Annie E. Casey Foundation to capture the “Parent and Student Voices on the OSP.” A total of 110 families, representing 180 students, that applied during the first two years of the Program volunteered to participate in this study. As the last installment in a four-part annual series that began in 2005, this report summarizes key findings from the previous reports and provides a general overview of the respondents’ “reflections” upon their three or four years in the Program. Using a phenomenological approach, which includes focus groups, personal interviews and keypad polling information gathering techniques, participants were given multiple opportunities to share or describe their experiences. A consumer framework was often used to contextualize the families’ experiences. Their insights continue to shape the scope and direction of the OSP, and they will help inform other efforts to provide low income families with access to quality school options

Incorporating Environmentally Compliant Manure Nutrient Disposal Costs into Least-Cost Livestock Ration Formulation

Livestock rations are formulated to minimize feed cost subject to nutritional requirements for a target performance level, which ignores the potentially substantial cost of disposing of nutrients fed in excess of nutritional requirements. We incorporate nutrient disposal costs into a modified least-cost ration formulation model to arrive at a joint least-cost decision that minimizes the sum of feed and net nutrient disposal costs. The method is demonstrated with phosphorus disposal costs on a representative dairy farm. Herd size, land availability and proximity, crop rotation, and initial soil phosphorus content are shown to be important in determining phosphorus disposal costs.environmental compliance, linear programming, livestock rations, manure disposal, Agribusiness, Environmental Economics and Policy, Livestock Production/Industries, C61, Q12, Q52,

The Evolution of School Choice Consumers: Parent and Student Voices on the Second Year of the D.C. Opportunity Scholarship Program

In the 50 years since economist Milton Friedman published The Role of Government in Education 1 scholars and policy makers have been debating how parental choice through market mechanisms can and does operate in education. Market optimists argue that education is a service that can be produced under a variety of arrangements and that parents are natural education consumers.2 Market pessimists argue that education is a public good that should be produced in government-run schools, and that school choice programs suffer market failure because only advantaged families will have the resources and experience to choose effectively.3 These academic debates continue to this day

ZNF804A genotype modulates neural activity during working memory for faces

Copyright © 2013 S. Karger AG, Basel.Peer reviewedPublisher PD

Satisfied, Optimistic, yet Concerned: Parent Voices on the Third Year of the DC Opportunity Scholarship Program

On January 23, 2004, President Bush signed the DC School Choice Incentive Act into law. This landmark piece of legislation included $14 million in funding for what would become the DC Opportunity Scholarship Program (OSP). The OSP is the first federally-funded K-12 scholarship program in the country and was designed to provide approximately 1,700 children from low income families with tuition scholarships worth up to$7,500. The scholarships cover the costs of attending nonpublic schools within the District of Columbia that agreed to participate in the Program. In December of 2006, Congress amended the DC School Choice Incentive Act to increase the continuing eligibility requirements from 200 percent of poverty line to 300 percent for families already enrolled in the Program.2 As a pilot program, the OSP is authorized to operate for five years and is being implemented by the Washington Scholarship Fund (WSF)